Merge branch 'for-2.6.25' of master.kernel.org:/pub/scm/linux/kernel/git/arnd/cell...

[mirror_ubuntu-bionic-kernel.git] / arch / powerpc / platforms / cell / spufs / switch.c

/*
 * spu_switch.c
 *
 * (C) Copyright IBM Corp. 2005
 *
 * Author: Mark Nutter <mnutter@us.ibm.com>
 *
 * Host-side part of SPU context switch sequence outlined in
 * Synergistic Processor Element, Book IV.
 *
 * A fully premptive switch of an SPE is very expensive in terms
 * of time and system resources.  SPE Book IV indicates that SPE
 * allocation should follow a "serially reusable device" model,
 * in which the SPE is assigned a task until it completes.  When
 * this is not possible, this sequence may be used to premptively
 * save, and then later (optionally) restore the context of a
 * program executing on an SPE.
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/hardirq.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/smp.h>
#include <linux/stddef.h>
#include <linux/unistd.h>

#include <asm/io.h>
#include <asm/spu.h>
#include <asm/spu_priv1.h>
#include <asm/spu_csa.h>
#include <asm/mmu_context.h>

#include "spufs.h"

#include "spu_save_dump.h"
#include "spu_restore_dump.h"

#if 0
#define POLL_WHILE_TRUE(_c) {                           \
    do {                                                \
    } while (_c);                                       \
  }
#else
#define RELAX_SPIN_COUNT                                1000
#define POLL_WHILE_TRUE(_c) {                           \
    do {                                                \
        int _i;                                         \
        for (_i=0; _i<RELAX_SPIN_COUNT && (_c); _i++) { \
            cpu_relax();                                \
        }                                               \
        if (unlikely(_c)) yield();                      \
        else break;                                     \
    } while (_c);                                       \
  }
#endif                          /* debug */

#define POLL_WHILE_FALSE(_c)    POLL_WHILE_TRUE(!(_c))

static inline void acquire_spu_lock(struct spu *spu)
{
        /* Save, Step 1:
         * Restore, Step 1:
         *    Acquire SPU-specific mutual exclusion lock.
         *    TBD.
         */
}

static inline void release_spu_lock(struct spu *spu)
{
        /* Restore, Step 76:
         *    Release SPU-specific mutual exclusion lock.
         *    TBD.
         */
}

static inline int check_spu_isolate(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        u32 isolate_state;

        /* Save, Step 2:
         * Save, Step 6:
         *     If SPU_Status[E,L,IS] any field is '1', this
         *     SPU is in isolate state and cannot be context
         *     saved at this time.
         */
        isolate_state = SPU_STATUS_ISOLATED_STATE |
            SPU_STATUS_ISOLATED_LOAD_STATUS | SPU_STATUS_ISOLATED_EXIT_STATUS;
        return (in_be32(&prob->spu_status_R) & isolate_state) ? 1 : 0;
}

static inline void disable_interrupts(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 3:
         * Restore, Step 2:
         *     Save INT_Mask_class0 in CSA.
         *     Write INT_MASK_class0 with value of 0.
         *     Save INT_Mask_class1 in CSA.
         *     Write INT_MASK_class1 with value of 0.
         *     Save INT_Mask_class2 in CSA.
         *     Write INT_MASK_class2 with value of 0.
         *     Synchronize all three interrupts to be sure
         *     we no longer execute a handler on another CPU.
         */
        spin_lock_irq(&spu->register_lock);
        if (csa) {
                csa->priv1.int_mask_class0_RW = spu_int_mask_get(spu, 0);
                csa->priv1.int_mask_class1_RW = spu_int_mask_get(spu, 1);
                csa->priv1.int_mask_class2_RW = spu_int_mask_get(spu, 2);
        }
        spu_int_mask_set(spu, 0, 0ul);
        spu_int_mask_set(spu, 1, 0ul);
        spu_int_mask_set(spu, 2, 0ul);
        eieio();
        spin_unlock_irq(&spu->register_lock);
        synchronize_irq(spu->irqs[0]);
        synchronize_irq(spu->irqs[1]);
        synchronize_irq(spu->irqs[2]);
}

static inline void set_watchdog_timer(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 4:
         * Restore, Step 25.
         *    Set a software watchdog timer, which specifies the
         *    maximum allowable time for a context save sequence.
         *
         *    For present, this implementation will not set a global
         *    watchdog timer, as virtualization & variable system load
         *    may cause unpredictable execution times.
         */
}

static inline void inhibit_user_access(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 5:
         * Restore, Step 3:
         *     Inhibit user-space access (if provided) to this
         *     SPU by unmapping the virtual pages assigned to
         *     the SPU memory-mapped I/O (MMIO) for problem
         *     state. TBD.
         */
}

static inline void set_switch_pending(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 7:
         * Restore, Step 5:
         *     Set a software context switch pending flag.
         */
        set_bit(SPU_CONTEXT_SWITCH_PENDING, &spu->flags);
        mb();
}

static inline void save_mfc_cntl(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 8:
         *     Suspend DMA and save MFC_CNTL.
         */
        switch (in_be64(&priv2->mfc_control_RW) &
               MFC_CNTL_SUSPEND_DMA_STATUS_MASK) {
        case MFC_CNTL_SUSPEND_IN_PROGRESS:
                POLL_WHILE_FALSE((in_be64(&priv2->mfc_control_RW) &
                                  MFC_CNTL_SUSPEND_DMA_STATUS_MASK) ==
                                 MFC_CNTL_SUSPEND_COMPLETE);
                /* fall through */
        case MFC_CNTL_SUSPEND_COMPLETE:
                if (csa) {
                        csa->priv2.mfc_control_RW =
                                MFC_CNTL_SUSPEND_MASK |
                                MFC_CNTL_SUSPEND_DMA_QUEUE;
                }
                break;
        case MFC_CNTL_NORMAL_DMA_QUEUE_OPERATION:
                out_be64(&priv2->mfc_control_RW, MFC_CNTL_SUSPEND_DMA_QUEUE);
                POLL_WHILE_FALSE((in_be64(&priv2->mfc_control_RW) &
                                  MFC_CNTL_SUSPEND_DMA_STATUS_MASK) ==
                                 MFC_CNTL_SUSPEND_COMPLETE);
                if (csa) {
                        csa->priv2.mfc_control_RW = 0;
                }
                break;
        }
}

static inline void save_spu_runcntl(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 9:
         *     Save SPU_Runcntl in the CSA.  This value contains
         *     the "Application Desired State".
         */
        csa->prob.spu_runcntl_RW = in_be32(&prob->spu_runcntl_RW);
}

static inline void save_mfc_sr1(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 10:
         *     Save MFC_SR1 in the CSA.
         */
        csa->priv1.mfc_sr1_RW = spu_mfc_sr1_get(spu);
}

static inline void save_spu_status(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 11:
         *     Read SPU_Status[R], and save to CSA.
         */
        if ((in_be32(&prob->spu_status_R) & SPU_STATUS_RUNNING) == 0) {
                csa->prob.spu_status_R = in_be32(&prob->spu_status_R);
        } else {
                u32 stopped;

                out_be32(&prob->spu_runcntl_RW, SPU_RUNCNTL_STOP);
                eieio();
                POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) &
                                SPU_STATUS_RUNNING);
                stopped =
                    SPU_STATUS_INVALID_INSTR | SPU_STATUS_SINGLE_STEP |
                    SPU_STATUS_STOPPED_BY_HALT | SPU_STATUS_STOPPED_BY_STOP;
                if ((in_be32(&prob->spu_status_R) & stopped) == 0)
                        csa->prob.spu_status_R = SPU_STATUS_RUNNING;
                else
                        csa->prob.spu_status_R = in_be32(&prob->spu_status_R);
        }
}

static inline void save_mfc_decr(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 12:
         *     Read MFC_CNTL[Ds].  Update saved copy of
         *     CSA.MFC_CNTL[Ds].
         */
        csa->priv2.mfc_control_RW |=
                in_be64(&priv2->mfc_control_RW) & MFC_CNTL_DECREMENTER_RUNNING;
}

static inline void halt_mfc_decr(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 13:
         *     Write MFC_CNTL[Dh] set to a '1' to halt
         *     the decrementer.
         */
        out_be64(&priv2->mfc_control_RW,
                 MFC_CNTL_DECREMENTER_HALTED | MFC_CNTL_SUSPEND_MASK);
        eieio();
}

static inline void save_timebase(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 14:
         *    Read PPE Timebase High and Timebase low registers
         *    and save in CSA.  TBD.
         */
        csa->suspend_time = get_cycles();
}

static inline void remove_other_spu_access(struct spu_state *csa,
                                           struct spu *spu)
{
        /* Save, Step 15:
         *     Remove other SPU access to this SPU by unmapping
         *     this SPU's pages from their address space.  TBD.
         */
}

static inline void do_mfc_mssync(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 16:
         * Restore, Step 11.
         *     Write SPU_MSSync register. Poll SPU_MSSync[P]
         *     for a value of 0.
         */
        out_be64(&prob->spc_mssync_RW, 1UL);
        POLL_WHILE_TRUE(in_be64(&prob->spc_mssync_RW) & MS_SYNC_PENDING);
}

static inline void issue_mfc_tlbie(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 17:
         * Restore, Step 12.
         * Restore, Step 48.
         *     Write TLB_Invalidate_Entry[IS,VPN,L,Lp]=0 register.
         *     Then issue a PPE sync instruction.
         */
        spu_tlb_invalidate(spu);
        mb();
}

static inline void handle_pending_interrupts(struct spu_state *csa,
                                             struct spu *spu)
{
        /* Save, Step 18:
         *     Handle any pending interrupts from this SPU
         *     here.  This is OS or hypervisor specific.  One
         *     option is to re-enable interrupts to handle any
         *     pending interrupts, with the interrupt handlers
         *     recognizing the software Context Switch Pending
         *     flag, to ensure the SPU execution or MFC command
         *     queue is not restarted.  TBD.
         */
}

static inline void save_mfc_queues(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        int i;

        /* Save, Step 19:
         *     If MFC_Cntl[Se]=0 then save
         *     MFC command queues.
         */
        if ((in_be64(&priv2->mfc_control_RW) & MFC_CNTL_DMA_QUEUES_EMPTY) == 0) {
                for (i = 0; i < 8; i++) {
                        csa->priv2.puq[i].mfc_cq_data0_RW =
                            in_be64(&priv2->puq[i].mfc_cq_data0_RW);
                        csa->priv2.puq[i].mfc_cq_data1_RW =
                            in_be64(&priv2->puq[i].mfc_cq_data1_RW);
                        csa->priv2.puq[i].mfc_cq_data2_RW =
                            in_be64(&priv2->puq[i].mfc_cq_data2_RW);
                        csa->priv2.puq[i].mfc_cq_data3_RW =
                            in_be64(&priv2->puq[i].mfc_cq_data3_RW);
                }
                for (i = 0; i < 16; i++) {
                        csa->priv2.spuq[i].mfc_cq_data0_RW =
                            in_be64(&priv2->spuq[i].mfc_cq_data0_RW);
                        csa->priv2.spuq[i].mfc_cq_data1_RW =
                            in_be64(&priv2->spuq[i].mfc_cq_data1_RW);
                        csa->priv2.spuq[i].mfc_cq_data2_RW =
                            in_be64(&priv2->spuq[i].mfc_cq_data2_RW);
                        csa->priv2.spuq[i].mfc_cq_data3_RW =
                            in_be64(&priv2->spuq[i].mfc_cq_data3_RW);
                }
        }
}

static inline void save_ppu_querymask(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 20:
         *     Save the PPU_QueryMask register
         *     in the CSA.
         */
        csa->prob.dma_querymask_RW = in_be32(&prob->dma_querymask_RW);
}

static inline void save_ppu_querytype(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 21:
         *     Save the PPU_QueryType register
         *     in the CSA.
         */
        csa->prob.dma_querytype_RW = in_be32(&prob->dma_querytype_RW);
}

static inline void save_ppu_tagstatus(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save the Prxy_TagStatus register in the CSA.
         *
         * It is unnecessary to restore dma_tagstatus_R, however,
         * dma_tagstatus_R in the CSA is accessed via backing_ops, so
         * we must save it.
         */
        csa->prob.dma_tagstatus_R = in_be32(&prob->dma_tagstatus_R);
}

static inline void save_mfc_csr_tsq(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 22:
         *     Save the MFC_CSR_TSQ register
         *     in the LSCSA.
         */
        csa->priv2.spu_tag_status_query_RW =
            in_be64(&priv2->spu_tag_status_query_RW);
}

static inline void save_mfc_csr_cmd(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 23:
         *     Save the MFC_CSR_CMD1 and MFC_CSR_CMD2
         *     registers in the CSA.
         */
        csa->priv2.spu_cmd_buf1_RW = in_be64(&priv2->spu_cmd_buf1_RW);
        csa->priv2.spu_cmd_buf2_RW = in_be64(&priv2->spu_cmd_buf2_RW);
}

static inline void save_mfc_csr_ato(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 24:
         *     Save the MFC_CSR_ATO register in
         *     the CSA.
         */
        csa->priv2.spu_atomic_status_RW = in_be64(&priv2->spu_atomic_status_RW);
}

static inline void save_mfc_tclass_id(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 25:
         *     Save the MFC_TCLASS_ID register in
         *     the CSA.
         */
        csa->priv1.mfc_tclass_id_RW = spu_mfc_tclass_id_get(spu);
}

static inline void set_mfc_tclass_id(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 26:
         * Restore, Step 23.
         *     Write the MFC_TCLASS_ID register with
         *     the value 0x10000000.
         */
        spu_mfc_tclass_id_set(spu, 0x10000000);
        eieio();
}

static inline void purge_mfc_queue(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 27:
         * Restore, Step 14.
         *     Write MFC_CNTL[Pc]=1 (purge queue).
         */
        out_be64(&priv2->mfc_control_RW, MFC_CNTL_PURGE_DMA_REQUEST);
        eieio();
}

static inline void wait_purge_complete(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 28:
         *     Poll MFC_CNTL[Ps] until value '11' is read
         *     (purge complete).
         */
        POLL_WHILE_FALSE((in_be64(&priv2->mfc_control_RW) &
                         MFC_CNTL_PURGE_DMA_STATUS_MASK) ==
                         MFC_CNTL_PURGE_DMA_COMPLETE);
}

static inline void setup_mfc_sr1(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 30:
         * Restore, Step 18:
         *     Write MFC_SR1 with MFC_SR1[D=0,S=1] and
         *     MFC_SR1[TL,R,Pr,T] set correctly for the
         *     OS specific environment.
         *
         *     Implementation note: The SPU-side code
         *     for save/restore is privileged, so the
         *     MFC_SR1[Pr] bit is not set.
         *
         */
        spu_mfc_sr1_set(spu, (MFC_STATE1_MASTER_RUN_CONTROL_MASK |
                              MFC_STATE1_RELOCATE_MASK |
                              MFC_STATE1_BUS_TLBIE_MASK));
}

static inline void save_spu_npc(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 31:
         *     Save SPU_NPC in the CSA.
         */
        csa->prob.spu_npc_RW = in_be32(&prob->spu_npc_RW);
}

static inline void save_spu_privcntl(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 32:
         *     Save SPU_PrivCntl in the CSA.
         */
        csa->priv2.spu_privcntl_RW = in_be64(&priv2->spu_privcntl_RW);
}

static inline void reset_spu_privcntl(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 33:
         * Restore, Step 16:
         *     Write SPU_PrivCntl[S,Le,A] fields reset to 0.
         */
        out_be64(&priv2->spu_privcntl_RW, 0UL);
        eieio();
}

static inline void save_spu_lslr(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 34:
         *     Save SPU_LSLR in the CSA.
         */
        csa->priv2.spu_lslr_RW = in_be64(&priv2->spu_lslr_RW);
}

static inline void reset_spu_lslr(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 35:
         * Restore, Step 17.
         *     Reset SPU_LSLR.
         */
        out_be64(&priv2->spu_lslr_RW, LS_ADDR_MASK);
        eieio();
}

static inline void save_spu_cfg(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 36:
         *     Save SPU_Cfg in the CSA.
         */
        csa->priv2.spu_cfg_RW = in_be64(&priv2->spu_cfg_RW);
}

static inline void save_pm_trace(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 37:
         *     Save PM_Trace_Tag_Wait_Mask in the CSA.
         *     Not performed by this implementation.
         */
}

static inline void save_mfc_rag(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 38:
         *     Save RA_GROUP_ID register and the
         *     RA_ENABLE reigster in the CSA.
         */
        csa->priv1.resource_allocation_groupID_RW =
                spu_resource_allocation_groupID_get(spu);
        csa->priv1.resource_allocation_enable_RW =
                spu_resource_allocation_enable_get(spu);
}

static inline void save_ppu_mb_stat(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 39:
         *     Save MB_Stat register in the CSA.
         */
        csa->prob.mb_stat_R = in_be32(&prob->mb_stat_R);
}

static inline void save_ppu_mb(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 40:
         *     Save the PPU_MB register in the CSA.
         */
        csa->prob.pu_mb_R = in_be32(&prob->pu_mb_R);
}

static inline void save_ppuint_mb(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 41:
         *     Save the PPUINT_MB register in the CSA.
         */
        csa->priv2.puint_mb_R = in_be64(&priv2->puint_mb_R);
}

static inline void save_ch_part1(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        u64 idx, ch_indices[] = { 0UL, 3UL, 4UL, 24UL, 25UL, 27UL };
        int i;

        /* Save, Step 42:
         */

        /* Save CH 1, without channel count */
        out_be64(&priv2->spu_chnlcntptr_RW, 1);
        csa->spu_chnldata_RW[1] = in_be64(&priv2->spu_chnldata_RW);

        /* Save the following CH: [0,3,4,24,25,27] */
        for (i = 0; i < ARRAY_SIZE(ch_indices); i++) {
                idx = ch_indices[i];
                out_be64(&priv2->spu_chnlcntptr_RW, idx);
                eieio();
                csa->spu_chnldata_RW[idx] = in_be64(&priv2->spu_chnldata_RW);
                csa->spu_chnlcnt_RW[idx] = in_be64(&priv2->spu_chnlcnt_RW);
                out_be64(&priv2->spu_chnldata_RW, 0UL);
                out_be64(&priv2->spu_chnlcnt_RW, 0UL);
                eieio();
        }
}

static inline void save_spu_mb(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        int i;

        /* Save, Step 43:
         *     Save SPU Read Mailbox Channel.
         */
        out_be64(&priv2->spu_chnlcntptr_RW, 29UL);
        eieio();
        csa->spu_chnlcnt_RW[29] = in_be64(&priv2->spu_chnlcnt_RW);
        for (i = 0; i < 4; i++) {
                csa->spu_mailbox_data[i] = in_be64(&priv2->spu_chnldata_RW);
        }
        out_be64(&priv2->spu_chnlcnt_RW, 0UL);
        eieio();
}

static inline void save_mfc_cmd(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 44:
         *     Save MFC_CMD Channel.
         */
        out_be64(&priv2->spu_chnlcntptr_RW, 21UL);
        eieio();
        csa->spu_chnlcnt_RW[21] = in_be64(&priv2->spu_chnlcnt_RW);
        eieio();
}

static inline void reset_ch(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        u64 ch_indices[4] = { 21UL, 23UL, 28UL, 30UL };
        u64 ch_counts[4] = { 16UL, 1UL, 1UL, 1UL };
        u64 idx;
        int i;

        /* Save, Step 45:
         *     Reset the following CH: [21, 23, 28, 30]
         */
        for (i = 0; i < 4; i++) {
                idx = ch_indices[i];
                out_be64(&priv2->spu_chnlcntptr_RW, idx);
                eieio();
                out_be64(&priv2->spu_chnlcnt_RW, ch_counts[i]);
                eieio();
        }
}

static inline void resume_mfc_queue(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Save, Step 46:
         * Restore, Step 25.
         *     Write MFC_CNTL[Sc]=0 (resume queue processing).
         */
        out_be64(&priv2->mfc_control_RW, MFC_CNTL_RESUME_DMA_QUEUE);
}

static inline void setup_mfc_slbs(struct spu_state *csa, struct spu *spu,
                unsigned int *code, int code_size)
{
        /* Save, Step 47:
         * Restore, Step 30.
         *     If MFC_SR1[R]=1, write 0 to SLB_Invalidate_All
         *     register, then initialize SLB_VSID and SLB_ESID
         *     to provide access to SPU context save code and
         *     LSCSA.
         *
         *     This implementation places both the context
         *     switch code and LSCSA in kernel address space.
         *
         *     Further this implementation assumes that the
         *     MFC_SR1[R]=1 (in other words, assume that
         *     translation is desired by OS environment).
         */
        spu_invalidate_slbs(spu);
        spu_setup_kernel_slbs(spu, csa->lscsa, code, code_size);
}

static inline void set_switch_active(struct spu_state *csa, struct spu *spu)
{
        /* Save, Step 48:
         * Restore, Step 23.
         *     Change the software context switch pending flag
         *     to context switch active.
         *
         *     This implementation does not uses a switch active flag.
         */
        clear_bit(SPU_CONTEXT_SWITCH_PENDING, &spu->flags);
        mb();
}

static inline void enable_interrupts(struct spu_state *csa, struct spu *spu)
{
        unsigned long class1_mask = CLASS1_ENABLE_SEGMENT_FAULT_INTR |
            CLASS1_ENABLE_STORAGE_FAULT_INTR;

        /* Save, Step 49:
         * Restore, Step 22:
         *     Reset and then enable interrupts, as
         *     needed by OS.
         *
         *     This implementation enables only class1
         *     (translation) interrupts.
         */
        spin_lock_irq(&spu->register_lock);
        spu_int_stat_clear(spu, 0, CLASS0_INTR_MASK);
        spu_int_stat_clear(spu, 1, CLASS1_INTR_MASK);
        spu_int_stat_clear(spu, 2, CLASS2_INTR_MASK);
        spu_int_mask_set(spu, 0, 0ul);
        spu_int_mask_set(spu, 1, class1_mask);
        spu_int_mask_set(spu, 2, 0ul);
        spin_unlock_irq(&spu->register_lock);
}

static inline int send_mfc_dma(struct spu *spu, unsigned long ea,
                               unsigned int ls_offset, unsigned int size,
                               unsigned int tag, unsigned int rclass,
                               unsigned int cmd)
{
        struct spu_problem __iomem *prob = spu->problem;
        union mfc_tag_size_class_cmd command;
        unsigned int transfer_size;
        volatile unsigned int status = 0x0;

        while (size > 0) {
                transfer_size =
                    (size > MFC_MAX_DMA_SIZE) ? MFC_MAX_DMA_SIZE : size;
                command.u.mfc_size = transfer_size;
                command.u.mfc_tag = tag;
                command.u.mfc_rclassid = rclass;
                command.u.mfc_cmd = cmd;
                do {
                        out_be32(&prob->mfc_lsa_W, ls_offset);
                        out_be64(&prob->mfc_ea_W, ea);
                        out_be64(&prob->mfc_union_W.all64, command.all64);
                        status =
                            in_be32(&prob->mfc_union_W.by32.mfc_class_cmd32);
                        if (unlikely(status & 0x2)) {
                                cpu_relax();
                        }
                } while (status & 0x3);
                size -= transfer_size;
                ea += transfer_size;
                ls_offset += transfer_size;
        }
        return 0;
}

static inline void save_ls_16kb(struct spu_state *csa, struct spu *spu)
{
        unsigned long addr = (unsigned long)&csa->lscsa->ls[0];
        unsigned int ls_offset = 0x0;
        unsigned int size = 16384;
        unsigned int tag = 0;
        unsigned int rclass = 0;
        unsigned int cmd = MFC_PUT_CMD;

        /* Save, Step 50:
         *     Issue a DMA command to copy the first 16K bytes
         *     of local storage to the CSA.
         */
        send_mfc_dma(spu, addr, ls_offset, size, tag, rclass, cmd);
}

static inline void set_spu_npc(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 51:
         * Restore, Step 31.
         *     Write SPU_NPC[IE]=0 and SPU_NPC[LSA] to entry
         *     point address of context save code in local
         *     storage.
         *
         *     This implementation uses SPU-side save/restore
         *     programs with entry points at LSA of 0.
         */
        out_be32(&prob->spu_npc_RW, 0);
        eieio();
}

static inline void set_signot1(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        union {
                u64 ull;
                u32 ui[2];
        } addr64;

        /* Save, Step 52:
         * Restore, Step 32:
         *    Write SPU_Sig_Notify_1 register with upper 32-bits
         *    of the CSA.LSCSA effective address.
         */
        addr64.ull = (u64) csa->lscsa;
        out_be32(&prob->signal_notify1, addr64.ui[0]);
        eieio();
}

static inline void set_signot2(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        union {
                u64 ull;
                u32 ui[2];
        } addr64;

        /* Save, Step 53:
         * Restore, Step 33:
         *    Write SPU_Sig_Notify_2 register with lower 32-bits
         *    of the CSA.LSCSA effective address.
         */
        addr64.ull = (u64) csa->lscsa;
        out_be32(&prob->signal_notify2, addr64.ui[1]);
        eieio();
}

static inline void send_save_code(struct spu_state *csa, struct spu *spu)
{
        unsigned long addr = (unsigned long)&spu_save_code[0];
        unsigned int ls_offset = 0x0;
        unsigned int size = sizeof(spu_save_code);
        unsigned int tag = 0;
        unsigned int rclass = 0;
        unsigned int cmd = MFC_GETFS_CMD;

        /* Save, Step 54:
         *     Issue a DMA command to copy context save code
         *     to local storage and start SPU.
         */
        send_mfc_dma(spu, addr, ls_offset, size, tag, rclass, cmd);
}

static inline void set_ppu_querymask(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Save, Step 55:
         * Restore, Step 38.
         *     Write PPU_QueryMask=1 (enable Tag Group 0)
         *     and issue eieio instruction.
         */
        out_be32(&prob->dma_querymask_RW, MFC_TAGID_TO_TAGMASK(0));
        eieio();
}

static inline void wait_tag_complete(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        u32 mask = MFC_TAGID_TO_TAGMASK(0);
        unsigned long flags;

        /* Save, Step 56:
         * Restore, Step 39.
         * Restore, Step 39.
         * Restore, Step 46.
         *     Poll PPU_TagStatus[gn] until 01 (Tag group 0 complete)
         *     or write PPU_QueryType[TS]=01 and wait for Tag Group
         *     Complete Interrupt.  Write INT_Stat_Class0 or
         *     INT_Stat_Class2 with value of 'handled'.
         */
        POLL_WHILE_FALSE(in_be32(&prob->dma_tagstatus_R) & mask);

        local_irq_save(flags);
        spu_int_stat_clear(spu, 0, CLASS0_INTR_MASK);
        spu_int_stat_clear(spu, 2, CLASS2_INTR_MASK);
        local_irq_restore(flags);
}

static inline void wait_spu_stopped(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        unsigned long flags;

        /* Save, Step 57:
         * Restore, Step 40.
         *     Poll until SPU_Status[R]=0 or wait for SPU Class 0
         *     or SPU Class 2 interrupt.  Write INT_Stat_class0
         *     or INT_Stat_class2 with value of handled.
         */
        POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) & SPU_STATUS_RUNNING);

        local_irq_save(flags);
        spu_int_stat_clear(spu, 0, CLASS0_INTR_MASK);
        spu_int_stat_clear(spu, 2, CLASS2_INTR_MASK);
        local_irq_restore(flags);
}

static inline int check_save_status(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        u32 complete;

        /* Save, Step 54:
         *     If SPU_Status[P]=1 and SPU_Status[SC] = "success",
         *     context save succeeded, otherwise context save
         *     failed.
         */
        complete = ((SPU_SAVE_COMPLETE << SPU_STOP_STATUS_SHIFT) |
                    SPU_STATUS_STOPPED_BY_STOP);
        return (in_be32(&prob->spu_status_R) != complete) ? 1 : 0;
}

static inline void terminate_spu_app(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 4:
         *    If required, notify the "using application" that
         *    the SPU task has been terminated.  TBD.
         */
}

static inline void suspend_mfc_and_halt_decr(struct spu_state *csa,
                struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 7:
         *     Write MFC_Cntl[Dh,Sc,Sm]='1','1','0' to suspend
         *     the queue and halt the decrementer.
         */
        out_be64(&priv2->mfc_control_RW, MFC_CNTL_SUSPEND_DMA_QUEUE |
                 MFC_CNTL_DECREMENTER_HALTED);
        eieio();
}

static inline void wait_suspend_mfc_complete(struct spu_state *csa,
                                             struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 8:
         * Restore, Step 47.
         *     Poll MFC_CNTL[Ss] until 11 is returned.
         */
        POLL_WHILE_FALSE((in_be64(&priv2->mfc_control_RW) &
                         MFC_CNTL_SUSPEND_DMA_STATUS_MASK) ==
                         MFC_CNTL_SUSPEND_COMPLETE);
}

static inline int suspend_spe(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Restore, Step 9:
         *    If SPU_Status[R]=1, stop SPU execution
         *    and wait for stop to complete.
         *
         *    Returns       1 if SPU_Status[R]=1 on entry.
         *                  0 otherwise
         */
        if (in_be32(&prob->spu_status_R) & SPU_STATUS_RUNNING) {
                if (in_be32(&prob->spu_status_R) &
                    SPU_STATUS_ISOLATED_EXIT_STATUS) {
                        POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) &
                                        SPU_STATUS_RUNNING);
                }
                if ((in_be32(&prob->spu_status_R) &
                     SPU_STATUS_ISOLATED_LOAD_STATUS)
                    || (in_be32(&prob->spu_status_R) &
                        SPU_STATUS_ISOLATED_STATE)) {
                        out_be32(&prob->spu_runcntl_RW, SPU_RUNCNTL_STOP);
                        eieio();
                        POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) &
                                        SPU_STATUS_RUNNING);
                        out_be32(&prob->spu_runcntl_RW, 0x2);
                        eieio();
                        POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) &
                                        SPU_STATUS_RUNNING);
                }
                if (in_be32(&prob->spu_status_R) &
                    SPU_STATUS_WAITING_FOR_CHANNEL) {
                        out_be32(&prob->spu_runcntl_RW, SPU_RUNCNTL_STOP);
                        eieio();
                        POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) &
                                        SPU_STATUS_RUNNING);
                }
                return 1;
        }
        return 0;
}

static inline void clear_spu_status(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Restore, Step 10:
         *    If SPU_Status[R]=0 and SPU_Status[E,L,IS]=1,
         *    release SPU from isolate state.
         */
        if (!(in_be32(&prob->spu_status_R) & SPU_STATUS_RUNNING)) {
                if (in_be32(&prob->spu_status_R) &
                    SPU_STATUS_ISOLATED_EXIT_STATUS) {
                        spu_mfc_sr1_set(spu,
                                        MFC_STATE1_MASTER_RUN_CONTROL_MASK);
                        eieio();
                        out_be32(&prob->spu_runcntl_RW, SPU_RUNCNTL_RUNNABLE);
                        eieio();
                        POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) &
                                        SPU_STATUS_RUNNING);
                }
                if ((in_be32(&prob->spu_status_R) &
                     SPU_STATUS_ISOLATED_LOAD_STATUS)
                    || (in_be32(&prob->spu_status_R) &
                        SPU_STATUS_ISOLATED_STATE)) {
                        spu_mfc_sr1_set(spu,
                                        MFC_STATE1_MASTER_RUN_CONTROL_MASK);
                        eieio();
                        out_be32(&prob->spu_runcntl_RW, 0x2);
                        eieio();
                        POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) &
                                        SPU_STATUS_RUNNING);
                }
        }
}

static inline void reset_ch_part1(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        u64 ch_indices[] = { 0UL, 3UL, 4UL, 24UL, 25UL, 27UL };
        u64 idx;
        int i;

        /* Restore, Step 20:
         */

        /* Reset CH 1 */
        out_be64(&priv2->spu_chnlcntptr_RW, 1);
        out_be64(&priv2->spu_chnldata_RW, 0UL);

        /* Reset the following CH: [0,3,4,24,25,27] */
        for (i = 0; i < ARRAY_SIZE(ch_indices); i++) {
                idx = ch_indices[i];
                out_be64(&priv2->spu_chnlcntptr_RW, idx);
                eieio();
                out_be64(&priv2->spu_chnldata_RW, 0UL);
                out_be64(&priv2->spu_chnlcnt_RW, 0UL);
                eieio();
        }
}

static inline void reset_ch_part2(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        u64 ch_indices[5] = { 21UL, 23UL, 28UL, 29UL, 30UL };
        u64 ch_counts[5] = { 16UL, 1UL, 1UL, 0UL, 1UL };
        u64 idx;
        int i;

        /* Restore, Step 21:
         *     Reset the following CH: [21, 23, 28, 29, 30]
         */
        for (i = 0; i < 5; i++) {
                idx = ch_indices[i];
                out_be64(&priv2->spu_chnlcntptr_RW, idx);
                eieio();
                out_be64(&priv2->spu_chnlcnt_RW, ch_counts[i]);
                eieio();
        }
}

static inline void setup_spu_status_part1(struct spu_state *csa,
                                          struct spu *spu)
{
        u32 status_P = SPU_STATUS_STOPPED_BY_STOP;
        u32 status_I = SPU_STATUS_INVALID_INSTR;
        u32 status_H = SPU_STATUS_STOPPED_BY_HALT;
        u32 status_S = SPU_STATUS_SINGLE_STEP;
        u32 status_S_I = SPU_STATUS_SINGLE_STEP | SPU_STATUS_INVALID_INSTR;
        u32 status_S_P = SPU_STATUS_SINGLE_STEP | SPU_STATUS_STOPPED_BY_STOP;
        u32 status_P_H = SPU_STATUS_STOPPED_BY_HALT |SPU_STATUS_STOPPED_BY_STOP;
        u32 status_P_I = SPU_STATUS_STOPPED_BY_STOP |SPU_STATUS_INVALID_INSTR;
        u32 status_code;

        /* Restore, Step 27:
         *     If the CSA.SPU_Status[I,S,H,P]=1 then add the correct
         *     instruction sequence to the end of the SPU based restore
         *     code (after the "context restored" stop and signal) to
         *     restore the correct SPU status.
         *
         *     NOTE: Rather than modifying the SPU executable, we
         *     instead add a new 'stopped_status' field to the
         *     LSCSA.  The SPU-side restore reads this field and
         *     takes the appropriate action when exiting.
         */

        status_code =
            (csa->prob.spu_status_R >> SPU_STOP_STATUS_SHIFT) & 0xFFFF;
        if ((csa->prob.spu_status_R & status_P_I) == status_P_I) {

                /* SPU_Status[P,I]=1 - Illegal Instruction followed
                 * by Stop and Signal instruction, followed by 'br -4'.
                 *
                 */
                csa->lscsa->stopped_status.slot[0] = SPU_STOPPED_STATUS_P_I;
                csa->lscsa->stopped_status.slot[1] = status_code;

        } else if ((csa->prob.spu_status_R & status_P_H) == status_P_H) {

                /* SPU_Status[P,H]=1 - Halt Conditional, followed
                 * by Stop and Signal instruction, followed by
                 * 'br -4'.
                 */
                csa->lscsa->stopped_status.slot[0] = SPU_STOPPED_STATUS_P_H;
                csa->lscsa->stopped_status.slot[1] = status_code;

        } else if ((csa->prob.spu_status_R & status_S_P) == status_S_P) {

                /* SPU_Status[S,P]=1 - Stop and Signal instruction
                 * followed by 'br -4'.
                 */
                csa->lscsa->stopped_status.slot[0] = SPU_STOPPED_STATUS_S_P;
                csa->lscsa->stopped_status.slot[1] = status_code;

        } else if ((csa->prob.spu_status_R & status_S_I) == status_S_I) {

                /* SPU_Status[S,I]=1 - Illegal instruction followed
                 * by 'br -4'.
                 */
                csa->lscsa->stopped_status.slot[0] = SPU_STOPPED_STATUS_S_I;
                csa->lscsa->stopped_status.slot[1] = status_code;

        } else if ((csa->prob.spu_status_R & status_P) == status_P) {

                /* SPU_Status[P]=1 - Stop and Signal instruction
                 * followed by 'br -4'.
                 */
                csa->lscsa->stopped_status.slot[0] = SPU_STOPPED_STATUS_P;
                csa->lscsa->stopped_status.slot[1] = status_code;

        } else if ((csa->prob.spu_status_R & status_H) == status_H) {

                /* SPU_Status[H]=1 - Halt Conditional, followed
                 * by 'br -4'.
                 */
                csa->lscsa->stopped_status.slot[0] = SPU_STOPPED_STATUS_H;

        } else if ((csa->prob.spu_status_R & status_S) == status_S) {

                /* SPU_Status[S]=1 - Two nop instructions.
                 */
                csa->lscsa->stopped_status.slot[0] = SPU_STOPPED_STATUS_S;

        } else if ((csa->prob.spu_status_R & status_I) == status_I) {

                /* SPU_Status[I]=1 - Illegal instruction followed
                 * by 'br -4'.
                 */
                csa->lscsa->stopped_status.slot[0] = SPU_STOPPED_STATUS_I;

        }
}

static inline void setup_spu_status_part2(struct spu_state *csa,
                                          struct spu *spu)
{
        u32 mask;

        /* Restore, Step 28:
         *     If the CSA.SPU_Status[I,S,H,P,R]=0 then
         *     add a 'br *' instruction to the end of
         *     the SPU based restore code.
         *
         *     NOTE: Rather than modifying the SPU executable, we
         *     instead add a new 'stopped_status' field to the
         *     LSCSA.  The SPU-side restore reads this field and
         *     takes the appropriate action when exiting.
         */
        mask = SPU_STATUS_INVALID_INSTR |
            SPU_STATUS_SINGLE_STEP |
            SPU_STATUS_STOPPED_BY_HALT |
            SPU_STATUS_STOPPED_BY_STOP | SPU_STATUS_RUNNING;
        if (!(csa->prob.spu_status_R & mask)) {
                csa->lscsa->stopped_status.slot[0] = SPU_STOPPED_STATUS_R;
        }
}

static inline void restore_mfc_rag(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 29:
         *     Restore RA_GROUP_ID register and the
         *     RA_ENABLE reigster from the CSA.
         */
        spu_resource_allocation_groupID_set(spu,
                        csa->priv1.resource_allocation_groupID_RW);
        spu_resource_allocation_enable_set(spu,
                        csa->priv1.resource_allocation_enable_RW);
}

static inline void send_restore_code(struct spu_state *csa, struct spu *spu)
{
        unsigned long addr = (unsigned long)&spu_restore_code[0];
        unsigned int ls_offset = 0x0;
        unsigned int size = sizeof(spu_restore_code);
        unsigned int tag = 0;
        unsigned int rclass = 0;
        unsigned int cmd = MFC_GETFS_CMD;

        /* Restore, Step 37:
         *     Issue MFC DMA command to copy context
         *     restore code to local storage.
         */
        send_mfc_dma(spu, addr, ls_offset, size, tag, rclass, cmd);
}

static inline void setup_decr(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 34:
         *     If CSA.MFC_CNTL[Ds]=1 (decrementer was
         *     running) then adjust decrementer, set
         *     decrementer running status in LSCSA,
         *     and set decrementer "wrapped" status
         *     in LSCSA.
         */
        if (csa->priv2.mfc_control_RW & MFC_CNTL_DECREMENTER_RUNNING) {
                cycles_t resume_time = get_cycles();
                cycles_t delta_time = resume_time - csa->suspend_time;

                csa->lscsa->decr_status.slot[0] = SPU_DECR_STATUS_RUNNING;
                if (csa->lscsa->decr.slot[0] < delta_time) {
                        csa->lscsa->decr_status.slot[0] |=
                                 SPU_DECR_STATUS_WRAPPED;
                }

                csa->lscsa->decr.slot[0] -= delta_time;
        } else {
                csa->lscsa->decr_status.slot[0] = 0;
        }
}

static inline void setup_ppu_mb(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 35:
         *     Copy the CSA.PU_MB data into the LSCSA.
         */
        csa->lscsa->ppu_mb.slot[0] = csa->prob.pu_mb_R;
}

static inline void setup_ppuint_mb(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 36:
         *     Copy the CSA.PUINT_MB data into the LSCSA.
         */
        csa->lscsa->ppuint_mb.slot[0] = csa->priv2.puint_mb_R;
}

static inline int check_restore_status(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        u32 complete;

        /* Restore, Step 40:
         *     If SPU_Status[P]=1 and SPU_Status[SC] = "success",
         *     context restore succeeded, otherwise context restore
         *     failed.
         */
        complete = ((SPU_RESTORE_COMPLETE << SPU_STOP_STATUS_SHIFT) |
                    SPU_STATUS_STOPPED_BY_STOP);
        return (in_be32(&prob->spu_status_R) != complete) ? 1 : 0;
}

static inline void restore_spu_privcntl(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 41:
         *     Restore SPU_PrivCntl from the CSA.
         */
        out_be64(&priv2->spu_privcntl_RW, csa->priv2.spu_privcntl_RW);
        eieio();
}

static inline void restore_status_part1(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        u32 mask;

        /* Restore, Step 42:
         *     If any CSA.SPU_Status[I,S,H,P]=1, then
         *     restore the error or single step state.
         */
        mask = SPU_STATUS_INVALID_INSTR |
            SPU_STATUS_SINGLE_STEP |
            SPU_STATUS_STOPPED_BY_HALT | SPU_STATUS_STOPPED_BY_STOP;
        if (csa->prob.spu_status_R & mask) {
                out_be32(&prob->spu_runcntl_RW, SPU_RUNCNTL_RUNNABLE);
                eieio();
                POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) &
                                SPU_STATUS_RUNNING);
        }
}

static inline void restore_status_part2(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        u32 mask;

        /* Restore, Step 43:
         *     If all CSA.SPU_Status[I,S,H,P,R]=0 then write
         *     SPU_RunCntl[R0R1]='01', wait for SPU_Status[R]=1,
         *     then write '00' to SPU_RunCntl[R0R1] and wait
         *     for SPU_Status[R]=0.
         */
        mask = SPU_STATUS_INVALID_INSTR |
            SPU_STATUS_SINGLE_STEP |
            SPU_STATUS_STOPPED_BY_HALT |
            SPU_STATUS_STOPPED_BY_STOP | SPU_STATUS_RUNNING;
        if (!(csa->prob.spu_status_R & mask)) {
                out_be32(&prob->spu_runcntl_RW, SPU_RUNCNTL_RUNNABLE);
                eieio();
                POLL_WHILE_FALSE(in_be32(&prob->spu_status_R) &
                                 SPU_STATUS_RUNNING);
                out_be32(&prob->spu_runcntl_RW, SPU_RUNCNTL_STOP);
                eieio();
                POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) &
                                SPU_STATUS_RUNNING);
        }
}

static inline void restore_ls_16kb(struct spu_state *csa, struct spu *spu)
{
        unsigned long addr = (unsigned long)&csa->lscsa->ls[0];
        unsigned int ls_offset = 0x0;
        unsigned int size = 16384;
        unsigned int tag = 0;
        unsigned int rclass = 0;
        unsigned int cmd = MFC_GET_CMD;

        /* Restore, Step 44:
         *     Issue a DMA command to restore the first
         *     16kb of local storage from CSA.
         */
        send_mfc_dma(spu, addr, ls_offset, size, tag, rclass, cmd);
}

static inline void suspend_mfc(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 47.
         *     Write MFC_Cntl[Sc,Sm]='1','0' to suspend
         *     the queue.
         */
        out_be64(&priv2->mfc_control_RW, MFC_CNTL_SUSPEND_DMA_QUEUE);
        eieio();
}

static inline void clear_interrupts(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 49:
         *     Write INT_MASK_class0 with value of 0.
         *     Write INT_MASK_class1 with value of 0.
         *     Write INT_MASK_class2 with value of 0.
         *     Write INT_STAT_class0 with value of -1.
         *     Write INT_STAT_class1 with value of -1.
         *     Write INT_STAT_class2 with value of -1.
         */
        spin_lock_irq(&spu->register_lock);
        spu_int_mask_set(spu, 0, 0ul);
        spu_int_mask_set(spu, 1, 0ul);
        spu_int_mask_set(spu, 2, 0ul);
        spu_int_stat_clear(spu, 0, CLASS0_INTR_MASK);
        spu_int_stat_clear(spu, 1, CLASS1_INTR_MASK);
        spu_int_stat_clear(spu, 2, CLASS2_INTR_MASK);
        spin_unlock_irq(&spu->register_lock);
}

static inline void restore_mfc_queues(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        int i;

        /* Restore, Step 50:
         *     If MFC_Cntl[Se]!=0 then restore
         *     MFC command queues.
         */
        if ((csa->priv2.mfc_control_RW & MFC_CNTL_DMA_QUEUES_EMPTY_MASK) == 0) {
                for (i = 0; i < 8; i++) {
                        out_be64(&priv2->puq[i].mfc_cq_data0_RW,
                                 csa->priv2.puq[i].mfc_cq_data0_RW);
                        out_be64(&priv2->puq[i].mfc_cq_data1_RW,
                                 csa->priv2.puq[i].mfc_cq_data1_RW);
                        out_be64(&priv2->puq[i].mfc_cq_data2_RW,
                                 csa->priv2.puq[i].mfc_cq_data2_RW);
                        out_be64(&priv2->puq[i].mfc_cq_data3_RW,
                                 csa->priv2.puq[i].mfc_cq_data3_RW);
                }
                for (i = 0; i < 16; i++) {
                        out_be64(&priv2->spuq[i].mfc_cq_data0_RW,
                                 csa->priv2.spuq[i].mfc_cq_data0_RW);
                        out_be64(&priv2->spuq[i].mfc_cq_data1_RW,
                                 csa->priv2.spuq[i].mfc_cq_data1_RW);
                        out_be64(&priv2->spuq[i].mfc_cq_data2_RW,
                                 csa->priv2.spuq[i].mfc_cq_data2_RW);
                        out_be64(&priv2->spuq[i].mfc_cq_data3_RW,
                                 csa->priv2.spuq[i].mfc_cq_data3_RW);
                }
        }
        eieio();
}

static inline void restore_ppu_querymask(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Restore, Step 51:
         *     Restore the PPU_QueryMask register from CSA.
         */
        out_be32(&prob->dma_querymask_RW, csa->prob.dma_querymask_RW);
        eieio();
}

static inline void restore_ppu_querytype(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Restore, Step 52:
         *     Restore the PPU_QueryType register from CSA.
         */
        out_be32(&prob->dma_querytype_RW, csa->prob.dma_querytype_RW);
        eieio();
}

static inline void restore_mfc_csr_tsq(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 53:
         *     Restore the MFC_CSR_TSQ register from CSA.
         */
        out_be64(&priv2->spu_tag_status_query_RW,
                 csa->priv2.spu_tag_status_query_RW);
        eieio();
}

static inline void restore_mfc_csr_cmd(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 54:
         *     Restore the MFC_CSR_CMD1 and MFC_CSR_CMD2
         *     registers from CSA.
         */
        out_be64(&priv2->spu_cmd_buf1_RW, csa->priv2.spu_cmd_buf1_RW);
        out_be64(&priv2->spu_cmd_buf2_RW, csa->priv2.spu_cmd_buf2_RW);
        eieio();
}

static inline void restore_mfc_csr_ato(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 55:
         *     Restore the MFC_CSR_ATO register from CSA.
         */
        out_be64(&priv2->spu_atomic_status_RW, csa->priv2.spu_atomic_status_RW);
}

static inline void restore_mfc_tclass_id(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 56:
         *     Restore the MFC_TCLASS_ID register from CSA.
         */
        spu_mfc_tclass_id_set(spu, csa->priv1.mfc_tclass_id_RW);
        eieio();
}

static inline void set_llr_event(struct spu_state *csa, struct spu *spu)
{
        u64 ch0_cnt, ch0_data;
        u64 ch1_data;

        /* Restore, Step 57:
         *    Set the Lock Line Reservation Lost Event by:
         *      1. OR CSA.SPU_Event_Status with bit 21 (Lr) set to 1.
         *      2. If CSA.SPU_Channel_0_Count=0 and
         *         CSA.SPU_Wr_Event_Mask[Lr]=1 and
         *         CSA.SPU_Event_Status[Lr]=0 then set
         *         CSA.SPU_Event_Status_Count=1.
         */
        ch0_cnt = csa->spu_chnlcnt_RW[0];
        ch0_data = csa->spu_chnldata_RW[0];
        ch1_data = csa->spu_chnldata_RW[1];
        csa->spu_chnldata_RW[0] |= MFC_LLR_LOST_EVENT;
        if ((ch0_cnt == 0) && !(ch0_data & MFC_LLR_LOST_EVENT) &&
            (ch1_data & MFC_LLR_LOST_EVENT)) {
                csa->spu_chnlcnt_RW[0] = 1;
        }
}

static inline void restore_decr_wrapped(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 58:
         *     If the status of the CSA software decrementer
         *     "wrapped" flag is set, OR in a '1' to
         *     CSA.SPU_Event_Status[Tm].
         */
        if (!(csa->lscsa->decr_status.slot[0] & SPU_DECR_STATUS_WRAPPED))
                return;

        if ((csa->spu_chnlcnt_RW[0] == 0) &&
            (csa->spu_chnldata_RW[1] & 0x20) &&
            !(csa->spu_chnldata_RW[0] & 0x20))
                csa->spu_chnlcnt_RW[0] = 1;

        csa->spu_chnldata_RW[0] |= 0x20;
}

static inline void restore_ch_part1(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        u64 idx, ch_indices[] = { 0UL, 3UL, 4UL, 24UL, 25UL, 27UL };
        int i;

        /* Restore, Step 59:
         *      Restore the following CH: [0,3,4,24,25,27]
         */
        for (i = 0; i < ARRAY_SIZE(ch_indices); i++) {
                idx = ch_indices[i];
                out_be64(&priv2->spu_chnlcntptr_RW, idx);
                eieio();
                out_be64(&priv2->spu_chnldata_RW, csa->spu_chnldata_RW[idx]);
                out_be64(&priv2->spu_chnlcnt_RW, csa->spu_chnlcnt_RW[idx]);
                eieio();
        }
}

static inline void restore_ch_part2(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        u64 ch_indices[3] = { 9UL, 21UL, 23UL };
        u64 ch_counts[3] = { 1UL, 16UL, 1UL };
        u64 idx;
        int i;

        /* Restore, Step 60:
         *     Restore the following CH: [9,21,23].
         */
        ch_counts[0] = 1UL;
        ch_counts[1] = csa->spu_chnlcnt_RW[21];
        ch_counts[2] = 1UL;
        for (i = 0; i < 3; i++) {
                idx = ch_indices[i];
                out_be64(&priv2->spu_chnlcntptr_RW, idx);
                eieio();
                out_be64(&priv2->spu_chnlcnt_RW, ch_counts[i]);
                eieio();
        }
}

static inline void restore_spu_lslr(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 61:
         *     Restore the SPU_LSLR register from CSA.
         */
        out_be64(&priv2->spu_lslr_RW, csa->priv2.spu_lslr_RW);
        eieio();
}

static inline void restore_spu_cfg(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 62:
         *     Restore the SPU_Cfg register from CSA.
         */
        out_be64(&priv2->spu_cfg_RW, csa->priv2.spu_cfg_RW);
        eieio();
}

static inline void restore_pm_trace(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 63:
         *     Restore PM_Trace_Tag_Wait_Mask from CSA.
         *     Not performed by this implementation.
         */
}

static inline void restore_spu_npc(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Restore, Step 64:
         *     Restore SPU_NPC from CSA.
         */
        out_be32(&prob->spu_npc_RW, csa->prob.spu_npc_RW);
        eieio();
}

static inline void restore_spu_mb(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        int i;

        /* Restore, Step 65:
         *     Restore MFC_RdSPU_MB from CSA.
         */
        out_be64(&priv2->spu_chnlcntptr_RW, 29UL);
        eieio();
        out_be64(&priv2->spu_chnlcnt_RW, csa->spu_chnlcnt_RW[29]);
        for (i = 0; i < 4; i++) {
                out_be64(&priv2->spu_chnldata_RW, csa->spu_mailbox_data[i]);
        }
        eieio();
}

static inline void check_ppu_mb_stat(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        u32 dummy = 0;

        /* Restore, Step 66:
         *     If CSA.MB_Stat[P]=0 (mailbox empty) then
         *     read from the PPU_MB register.
         */
        if ((csa->prob.mb_stat_R & 0xFF) == 0) {
                dummy = in_be32(&prob->pu_mb_R);
                eieio();
        }
}

static inline void check_ppuint_mb_stat(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;
        u64 dummy = 0UL;

        /* Restore, Step 66:
         *     If CSA.MB_Stat[I]=0 (mailbox empty) then
         *     read from the PPUINT_MB register.
         */
        if ((csa->prob.mb_stat_R & 0xFF0000) == 0) {
                dummy = in_be64(&priv2->puint_mb_R);
                eieio();
                spu_int_stat_clear(spu, 2, CLASS2_ENABLE_MAILBOX_INTR);
                eieio();
        }
}

static inline void restore_mfc_sr1(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 69:
         *     Restore the MFC_SR1 register from CSA.
         */
        spu_mfc_sr1_set(spu, csa->priv1.mfc_sr1_RW);
        eieio();
}

static inline void restore_other_spu_access(struct spu_state *csa,
                                            struct spu *spu)
{
        /* Restore, Step 70:
         *     Restore other SPU mappings to this SPU. TBD.
         */
}

static inline void restore_spu_runcntl(struct spu_state *csa, struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        /* Restore, Step 71:
         *     If CSA.SPU_Status[R]=1 then write
         *     SPU_RunCntl[R0R1]='01'.
         */
        if (csa->prob.spu_status_R & SPU_STATUS_RUNNING) {
                out_be32(&prob->spu_runcntl_RW, SPU_RUNCNTL_RUNNABLE);
                eieio();
        }
}

static inline void restore_mfc_cntl(struct spu_state *csa, struct spu *spu)
{
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Restore, Step 72:
         *    Restore the MFC_CNTL register for the CSA.
         */
        out_be64(&priv2->mfc_control_RW, csa->priv2.mfc_control_RW);
        eieio();
        /*
         * FIXME: this is to restart a DMA that we were processing
         *        before the save. better remember the fault information
         *        in the csa instead.
         */
        if ((csa->priv2.mfc_control_RW & MFC_CNTL_SUSPEND_DMA_QUEUE_MASK)) {
                out_be64(&priv2->mfc_control_RW, MFC_CNTL_RESTART_DMA_COMMAND);
                eieio();
        }
}

static inline void enable_user_access(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 73:
         *     Enable user-space access (if provided) to this
         *     SPU by mapping the virtual pages assigned to
         *     the SPU memory-mapped I/O (MMIO) for problem
         *     state. TBD.
         */
}

static inline void reset_switch_active(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 74:
         *     Reset the "context switch active" flag.
         *     Not performed by this implementation.
         */
}

static inline void reenable_interrupts(struct spu_state *csa, struct spu *spu)
{
        /* Restore, Step 75:
         *     Re-enable SPU interrupts.
         */
        spin_lock_irq(&spu->register_lock);
        spu_int_mask_set(spu, 0, csa->priv1.int_mask_class0_RW);
        spu_int_mask_set(spu, 1, csa->priv1.int_mask_class1_RW);
        spu_int_mask_set(spu, 2, csa->priv1.int_mask_class2_RW);
        spin_unlock_irq(&spu->register_lock);
}

static int quiece_spu(struct spu_state *prev, struct spu *spu)
{
        /*
         * Combined steps 2-18 of SPU context save sequence, which
         * quiesce the SPU state (disable SPU execution, MFC command
         * queues, decrementer, SPU interrupts, etc.).
         *
         * Returns      0 on success.
         *              2 if failed step 2.
         *              6 if failed step 6.
         */

        if (check_spu_isolate(prev, spu)) {     /* Step 2. */
                return 2;
        }
        disable_interrupts(prev, spu);          /* Step 3. */
        set_watchdog_timer(prev, spu);          /* Step 4. */
        inhibit_user_access(prev, spu);         /* Step 5. */
        if (check_spu_isolate(prev, spu)) {     /* Step 6. */
                return 6;
        }
        set_switch_pending(prev, spu);          /* Step 7. */
        save_mfc_cntl(prev, spu);               /* Step 8. */
        save_spu_runcntl(prev, spu);            /* Step 9. */
        save_mfc_sr1(prev, spu);                /* Step 10. */
        save_spu_status(prev, spu);             /* Step 11. */
        save_mfc_decr(prev, spu);               /* Step 12. */
        halt_mfc_decr(prev, spu);               /* Step 13. */
        save_timebase(prev, spu);               /* Step 14. */
        remove_other_spu_access(prev, spu);     /* Step 15. */
        do_mfc_mssync(prev, spu);               /* Step 16. */
        issue_mfc_tlbie(prev, spu);             /* Step 17. */
        handle_pending_interrupts(prev, spu);   /* Step 18. */

        return 0;
}

static void save_csa(struct spu_state *prev, struct spu *spu)
{
        /*
         * Combine steps 19-44 of SPU context save sequence, which
         * save regions of the privileged & problem state areas.
         */

        save_mfc_queues(prev, spu);     /* Step 19. */
        save_ppu_querymask(prev, spu);  /* Step 20. */
        save_ppu_querytype(prev, spu);  /* Step 21. */
        save_ppu_tagstatus(prev, spu);  /* NEW.     */
        save_mfc_csr_tsq(prev, spu);    /* Step 22. */
        save_mfc_csr_cmd(prev, spu);    /* Step 23. */
        save_mfc_csr_ato(prev, spu);    /* Step 24. */
        save_mfc_tclass_id(prev, spu);  /* Step 25. */
        set_mfc_tclass_id(prev, spu);   /* Step 26. */
        purge_mfc_queue(prev, spu);     /* Step 27. */
        wait_purge_complete(prev, spu); /* Step 28. */
        setup_mfc_sr1(prev, spu);       /* Step 30. */
        save_spu_npc(prev, spu);        /* Step 31. */
        save_spu_privcntl(prev, spu);   /* Step 32. */
        reset_spu_privcntl(prev, spu);  /* Step 33. */
        save_spu_lslr(prev, spu);       /* Step 34. */
        reset_spu_lslr(prev, spu);      /* Step 35. */
        save_spu_cfg(prev, spu);        /* Step 36. */
        save_pm_trace(prev, spu);       /* Step 37. */
        save_mfc_rag(prev, spu);        /* Step 38. */
        save_ppu_mb_stat(prev, spu);    /* Step 39. */
        save_ppu_mb(prev, spu);         /* Step 40. */
        save_ppuint_mb(prev, spu);      /* Step 41. */
        save_ch_part1(prev, spu);       /* Step 42. */
        save_spu_mb(prev, spu);         /* Step 43. */
        save_mfc_cmd(prev, spu);        /* Step 44. */
        reset_ch(prev, spu);            /* Step 45. */
}

static void save_lscsa(struct spu_state *prev, struct spu *spu)
{
        /*
         * Perform steps 46-57 of SPU context save sequence,
         * which save regions of the local store and register
         * file.
         */

        resume_mfc_queue(prev, spu);    /* Step 46. */
        /* Step 47. */
        setup_mfc_slbs(prev, spu, spu_save_code, sizeof(spu_save_code));
        set_switch_active(prev, spu);   /* Step 48. */
        enable_interrupts(prev, spu);   /* Step 49. */
        save_ls_16kb(prev, spu);        /* Step 50. */
        set_spu_npc(prev, spu);         /* Step 51. */
        set_signot1(prev, spu);         /* Step 52. */
        set_signot2(prev, spu);         /* Step 53. */
        send_save_code(prev, spu);      /* Step 54. */
        set_ppu_querymask(prev, spu);   /* Step 55. */
        wait_tag_complete(prev, spu);   /* Step 56. */
        wait_spu_stopped(prev, spu);    /* Step 57. */
}

static void force_spu_isolate_exit(struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;
        struct spu_priv2 __iomem *priv2 = spu->priv2;

        /* Stop SPE execution and wait for completion. */
        out_be32(&prob->spu_runcntl_RW, SPU_RUNCNTL_STOP);
        iobarrier_rw();
        POLL_WHILE_TRUE(in_be32(&prob->spu_status_R) & SPU_STATUS_RUNNING);

        /* Restart SPE master runcntl. */
        spu_mfc_sr1_set(spu, MFC_STATE1_MASTER_RUN_CONTROL_MASK);
        iobarrier_w();

        /* Initiate isolate exit request and wait for completion. */
        out_be64(&priv2->spu_privcntl_RW, 4LL);
        iobarrier_w();
        out_be32(&prob->spu_runcntl_RW, 2);
        iobarrier_rw();
        POLL_WHILE_FALSE((in_be32(&prob->spu_status_R)
                                & SPU_STATUS_STOPPED_BY_STOP));

        /* Reset load request to normal. */
        out_be64(&priv2->spu_privcntl_RW, SPU_PRIVCNT_LOAD_REQUEST_NORMAL);
        iobarrier_w();
}

/**
 * stop_spu_isolate
 *      Check SPU run-control state and force isolated
 *      exit function as necessary.
 */
static void stop_spu_isolate(struct spu *spu)
{
        struct spu_problem __iomem *prob = spu->problem;

        if (in_be32(&prob->spu_status_R) & SPU_STATUS_ISOLATED_STATE) {
                /* The SPU is in isolated state; the only way
                 * to get it out is to perform an isolated
                 * exit (clean) operation.
                 */
                force_spu_isolate_exit(spu);
        }
}

static void harvest(struct spu_state *prev, struct spu *spu)
{
        /*
         * Perform steps 2-25 of SPU context restore sequence,
         * which resets an SPU either after a failed save, or
         * when using SPU for first time.
         */

        disable_interrupts(prev, spu);          /* Step 2.  */
        inhibit_user_access(prev, spu);         /* Step 3.  */
        terminate_spu_app(prev, spu);           /* Step 4.  */
        set_switch_pending(prev, spu);          /* Step 5.  */
        stop_spu_isolate(spu);                  /* NEW.     */
        remove_other_spu_access(prev, spu);     /* Step 6.  */
        suspend_mfc_and_halt_decr(prev, spu);   /* Step 7.  */
        wait_suspend_mfc_complete(prev, spu);   /* Step 8.  */
        if (!suspend_spe(prev, spu))            /* Step 9.  */
                clear_spu_status(prev, spu);    /* Step 10. */
        do_mfc_mssync(prev, spu);               /* Step 11. */
        issue_mfc_tlbie(prev, spu);             /* Step 12. */
        handle_pending_interrupts(prev, spu);   /* Step 13. */
        purge_mfc_queue(prev, spu);             /* Step 14. */
        wait_purge_complete(prev, spu);         /* Step 15. */
        reset_spu_privcntl(prev, spu);          /* Step 16. */
        reset_spu_lslr(prev, spu);              /* Step 17. */
        setup_mfc_sr1(prev, spu);               /* Step 18. */
        spu_invalidate_slbs(spu);               /* Step 19. */
        reset_ch_part1(prev, spu);              /* Step 20. */
        reset_ch_part2(prev, spu);              /* Step 21. */
        enable_interrupts(prev, spu);           /* Step 22. */
        set_switch_active(prev, spu);           /* Step 23. */
        set_mfc_tclass_id(prev, spu);           /* Step 24. */
        resume_mfc_queue(prev, spu);            /* Step 25. */
}

static void restore_lscsa(struct spu_state *next, struct spu *spu)
{
        /*
         * Perform steps 26-40 of SPU context restore sequence,
         * which restores regions of the local store and register
         * file.
         */

        set_watchdog_timer(next, spu);          /* Step 26. */
        setup_spu_status_part1(next, spu);      /* Step 27. */
        setup_spu_status_part2(next, spu);      /* Step 28. */
        restore_mfc_rag(next, spu);             /* Step 29. */
        /* Step 30. */
        setup_mfc_slbs(next, spu, spu_restore_code, sizeof(spu_restore_code));
        set_spu_npc(next, spu);                 /* Step 31. */
        set_signot1(next, spu);                 /* Step 32. */
        set_signot2(next, spu);                 /* Step 33. */
        setup_decr(next, spu);                  /* Step 34. */
        setup_ppu_mb(next, spu);                /* Step 35. */
        setup_ppuint_mb(next, spu);             /* Step 36. */
        send_restore_code(next, spu);           /* Step 37. */
        set_ppu_querymask(next, spu);           /* Step 38. */
        wait_tag_complete(next, spu);           /* Step 39. */
        wait_spu_stopped(next, spu);            /* Step 40. */
}

static void restore_csa(struct spu_state *next, struct spu *spu)
{
        /*
         * Combine steps 41-76 of SPU context restore sequence, which
         * restore regions of the privileged & problem state areas.
         */

        restore_spu_privcntl(next, spu);        /* Step 41. */
        restore_status_part1(next, spu);        /* Step 42. */
        restore_status_part2(next, spu);        /* Step 43. */
        restore_ls_16kb(next, spu);             /* Step 44. */
        wait_tag_complete(next, spu);           /* Step 45. */
        suspend_mfc(next, spu);                 /* Step 46. */
        wait_suspend_mfc_complete(next, spu);   /* Step 47. */
        issue_mfc_tlbie(next, spu);             /* Step 48. */
        clear_interrupts(next, spu);            /* Step 49. */
        restore_mfc_queues(next, spu);          /* Step 50. */
        restore_ppu_querymask(next, spu);       /* Step 51. */
        restore_ppu_querytype(next, spu);       /* Step 52. */
        restore_mfc_csr_tsq(next, spu);         /* Step 53. */
        restore_mfc_csr_cmd(next, spu);         /* Step 54. */
        restore_mfc_csr_ato(next, spu);         /* Step 55. */
        restore_mfc_tclass_id(next, spu);       /* Step 56. */
        set_llr_event(next, spu);               /* Step 57. */
        restore_decr_wrapped(next, spu);        /* Step 58. */
        restore_ch_part1(next, spu);            /* Step 59. */
        restore_ch_part2(next, spu);            /* Step 60. */
        restore_spu_lslr(next, spu);            /* Step 61. */
        restore_spu_cfg(next, spu);             /* Step 62. */
        restore_pm_trace(next, spu);            /* Step 63. */
        restore_spu_npc(next, spu);             /* Step 64. */
        restore_spu_mb(next, spu);              /* Step 65. */
        check_ppu_mb_stat(next, spu);           /* Step 66. */
        check_ppuint_mb_stat(next, spu);        /* Step 67. */
        spu_invalidate_slbs(spu);               /* Modified Step 68. */
        restore_mfc_sr1(next, spu);             /* Step 69. */
        restore_other_spu_access(next, spu);    /* Step 70. */
        restore_spu_runcntl(next, spu);         /* Step 71. */
        restore_mfc_cntl(next, spu);            /* Step 72. */
        enable_user_access(next, spu);          /* Step 73. */
        reset_switch_active(next, spu);         /* Step 74. */
        reenable_interrupts(next, spu);         /* Step 75. */
}

static int __do_spu_save(struct spu_state *prev, struct spu *spu)
{
        int rc;

        /*
         * SPU context save can be broken into three phases:
         *
         *     (a) quiesce [steps 2-16].
         *     (b) save of CSA, performed by PPE [steps 17-42]
         *     (c) save of LSCSA, mostly performed by SPU [steps 43-52].
         *
         * Returns      0 on success.
         *              2,6 if failed to quiece SPU
         *              53 if SPU-side of save failed.
         */

        rc = quiece_spu(prev, spu);             /* Steps 2-16. */
        switch (rc) {
        default:
        case 2:
        case 6:
                harvest(prev, spu);
                return rc;
                break;
        case 0:
                break;
        }
        save_csa(prev, spu);                    /* Steps 17-43. */
        save_lscsa(prev, spu);                  /* Steps 44-53. */
        return check_save_status(prev, spu);    /* Step 54.     */
}

static int __do_spu_restore(struct spu_state *next, struct spu *spu)
{
        int rc;

        /*
         * SPU context restore can be broken into three phases:
         *
         *    (a) harvest (or reset) SPU [steps 2-24].
         *    (b) restore LSCSA [steps 25-40], mostly performed by SPU.
         *    (c) restore CSA [steps 41-76], performed by PPE.
         *
         * The 'harvest' step is not performed here, but rather
         * as needed below.
         */

        restore_lscsa(next, spu);               /* Steps 24-39. */
        rc = check_restore_status(next, spu);   /* Step 40.     */
        switch (rc) {
        default:
                /* Failed. Return now. */
                return rc;
                break;
        case 0:
                /* Fall through to next step. */
                break;
        }
        restore_csa(next, spu);

        return 0;
}

/**
 * spu_save - SPU context save, with locking.
 * @prev: pointer to SPU context save area, to be saved.
 * @spu: pointer to SPU iomem structure.
 *
 * Acquire locks, perform the save operation then return.
 */
int spu_save(struct spu_state *prev, struct spu *spu)
{
        int rc;

        acquire_spu_lock(spu);          /* Step 1.     */
        rc = __do_spu_save(prev, spu);  /* Steps 2-53. */
        release_spu_lock(spu);
        if (rc != 0 && rc != 2 && rc != 6) {
                panic("%s failed on SPU[%d], rc=%d.\n",
                      __func__, spu->number, rc);
        }
        return 0;
}
EXPORT_SYMBOL_GPL(spu_save);

/**
 * spu_restore - SPU context restore, with harvest and locking.
 * @new: pointer to SPU context save area, to be restored.
 * @spu: pointer to SPU iomem structure.
 *
 * Perform harvest + restore, as we may not be coming
 * from a previous successful save operation, and the
 * hardware state is unknown.
 */
int spu_restore(struct spu_state *new, struct spu *spu)
{
        int rc;

        acquire_spu_lock(spu);
        harvest(NULL, spu);
        spu->slb_replace = 0;
        rc = __do_spu_restore(new, spu);
        release_spu_lock(spu);
        if (rc) {
                panic("%s failed on SPU[%d] rc=%d.\n",
                       __func__, spu->number, rc);
        }
        return rc;
}
EXPORT_SYMBOL_GPL(spu_restore);

static void init_prob(struct spu_state *csa)
{
        csa->spu_chnlcnt_RW[9] = 1;
        csa->spu_chnlcnt_RW[21] = 16;
        csa->spu_chnlcnt_RW[23] = 1;
        csa->spu_chnlcnt_RW[28] = 1;
        csa->spu_chnlcnt_RW[30] = 1;
        csa->prob.spu_runcntl_RW = SPU_RUNCNTL_STOP;
        csa->prob.mb_stat_R = 0x000400;
}

static void init_priv1(struct spu_state *csa)
{
        /* Enable decode, relocate, tlbie response, master runcntl. */
        csa->priv1.mfc_sr1_RW = MFC_STATE1_LOCAL_STORAGE_DECODE_MASK |
            MFC_STATE1_MASTER_RUN_CONTROL_MASK |
            MFC_STATE1_PROBLEM_STATE_MASK |
            MFC_STATE1_RELOCATE_MASK | MFC_STATE1_BUS_TLBIE_MASK;

        /* Enable OS-specific set of interrupts. */
        csa->priv1.int_mask_class0_RW = CLASS0_ENABLE_DMA_ALIGNMENT_INTR |
            CLASS0_ENABLE_INVALID_DMA_COMMAND_INTR |
            CLASS0_ENABLE_SPU_ERROR_INTR;
        csa->priv1.int_mask_class1_RW = CLASS1_ENABLE_SEGMENT_FAULT_INTR |
            CLASS1_ENABLE_STORAGE_FAULT_INTR;
        csa->priv1.int_mask_class2_RW = CLASS2_ENABLE_SPU_STOP_INTR |
            CLASS2_ENABLE_SPU_HALT_INTR |
            CLASS2_ENABLE_SPU_DMA_TAG_GROUP_COMPLETE_INTR;
}

static void init_priv2(struct spu_state *csa)
{
        csa->priv2.spu_lslr_RW = LS_ADDR_MASK;
        csa->priv2.mfc_control_RW = MFC_CNTL_RESUME_DMA_QUEUE |
            MFC_CNTL_NORMAL_DMA_QUEUE_OPERATION |
            MFC_CNTL_DMA_QUEUES_EMPTY_MASK;
}

/**
 * spu_alloc_csa - allocate and initialize an SPU context save area.
 *
 * Allocate and initialize the contents of an SPU context save area.
 * This includes enabling address translation, interrupt masks, etc.,
 * as appropriate for the given OS environment.
 *
 * Note that storage for the 'lscsa' is allocated separately,
 * as it is by far the largest of the context save regions,
 * and may need to be pinned or otherwise specially aligned.
 */
int spu_init_csa(struct spu_state *csa)
{
        int rc;

        if (!csa)
                return -EINVAL;
        memset(csa, 0, sizeof(struct spu_state));

        rc = spu_alloc_lscsa(csa);
        if (rc)
                return rc;

        spin_lock_init(&csa->register_lock);

        init_prob(csa);
        init_priv1(csa);
        init_priv2(csa);

        return 0;
}

void spu_fini_csa(struct spu_state *csa)
{
        spu_free_lscsa(csa);
}