ASoC: sti: fix missing clk_disable_unprepare() on error in uni_player_start()

[mirror_ubuntu-zesty-kernel.git] / drivers / misc / cxl / native.c

/*
 * Copyright 2014 IBM Corp.
 *
 * 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 of the License, or (at your option) any later version.
 */

#include <linux/spinlock.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/mutex.h>
#include <linux/mm.h>
#include <linux/uaccess.h>
#include <linux/delay.h>
#include <asm/synch.h>
#include <misc/cxl-base.h>

#include "cxl.h"
#include "trace.h"

static int afu_control(struct cxl_afu *afu, u64 command, u64 clear,
                       u64 result, u64 mask, bool enabled)
{
        u64 AFU_Cntl;
        unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
        int rc = 0;

        spin_lock(&afu->afu_cntl_lock);
        pr_devel("AFU command starting: %llx\n", command);

        trace_cxl_afu_ctrl(afu, command);

        AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
        cxl_p2n_write(afu, CXL_AFU_Cntl_An, (AFU_Cntl & ~clear) | command);

        AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
        while ((AFU_Cntl & mask) != result) {
                if (time_after_eq(jiffies, timeout)) {
                        dev_warn(&afu->dev, "WARNING: AFU control timed out!\n");
                        rc = -EBUSY;
                        goto out;
                }

                if (!cxl_ops->link_ok(afu->adapter, afu)) {
                        afu->enabled = enabled;
                        rc = -EIO;
                        goto out;
                }

                pr_devel_ratelimited("AFU control... (0x%016llx)\n",
                                     AFU_Cntl | command);
                cpu_relax();
                AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
        };

        if (AFU_Cntl & CXL_AFU_Cntl_An_RA) {
                /*
                 * Workaround for a bug in the XSL used in the Mellanox CX4
                 * that fails to clear the RA bit after an AFU reset,
                 * preventing subsequent AFU resets from working.
                 */
                cxl_p2n_write(afu, CXL_AFU_Cntl_An, AFU_Cntl & ~CXL_AFU_Cntl_An_RA);
        }

        pr_devel("AFU command complete: %llx\n", command);
        afu->enabled = enabled;
out:
        trace_cxl_afu_ctrl_done(afu, command, rc);
        spin_unlock(&afu->afu_cntl_lock);

        return rc;
}

static int afu_enable(struct cxl_afu *afu)
{
        pr_devel("AFU enable request\n");

        return afu_control(afu, CXL_AFU_Cntl_An_E, 0,
                           CXL_AFU_Cntl_An_ES_Enabled,
                           CXL_AFU_Cntl_An_ES_MASK, true);
}

int cxl_afu_disable(struct cxl_afu *afu)
{
        pr_devel("AFU disable request\n");

        return afu_control(afu, 0, CXL_AFU_Cntl_An_E,
                           CXL_AFU_Cntl_An_ES_Disabled,
                           CXL_AFU_Cntl_An_ES_MASK, false);
}

/* This will disable as well as reset */
static int native_afu_reset(struct cxl_afu *afu)
{
        pr_devel("AFU reset request\n");

        return afu_control(afu, CXL_AFU_Cntl_An_RA, 0,
                           CXL_AFU_Cntl_An_RS_Complete | CXL_AFU_Cntl_An_ES_Disabled,
                           CXL_AFU_Cntl_An_RS_MASK | CXL_AFU_Cntl_An_ES_MASK,
                           false);
}

static int native_afu_check_and_enable(struct cxl_afu *afu)
{
        if (!cxl_ops->link_ok(afu->adapter, afu)) {
                WARN(1, "Refusing to enable afu while link down!\n");
                return -EIO;
        }
        if (afu->enabled)
                return 0;
        return afu_enable(afu);
}

int cxl_psl_purge(struct cxl_afu *afu)
{
        u64 PSL_CNTL = cxl_p1n_read(afu, CXL_PSL_SCNTL_An);
        u64 AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
        u64 dsisr, dar;
        u64 start, end;
        unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
        int rc = 0;

        trace_cxl_psl_ctrl(afu, CXL_PSL_SCNTL_An_Pc);

        pr_devel("PSL purge request\n");

        if (!cxl_ops->link_ok(afu->adapter, afu)) {
                dev_warn(&afu->dev, "PSL Purge called with link down, ignoring\n");
                rc = -EIO;
                goto out;
        }

        if ((AFU_Cntl & CXL_AFU_Cntl_An_ES_MASK) != CXL_AFU_Cntl_An_ES_Disabled) {
                WARN(1, "psl_purge request while AFU not disabled!\n");
                cxl_afu_disable(afu);
        }

        cxl_p1n_write(afu, CXL_PSL_SCNTL_An,
                       PSL_CNTL | CXL_PSL_SCNTL_An_Pc);
        start = local_clock();
        PSL_CNTL = cxl_p1n_read(afu, CXL_PSL_SCNTL_An);
        while ((PSL_CNTL &  CXL_PSL_SCNTL_An_Ps_MASK)
                        == CXL_PSL_SCNTL_An_Ps_Pending) {
                if (time_after_eq(jiffies, timeout)) {
                        dev_warn(&afu->dev, "WARNING: PSL Purge timed out!\n");
                        rc = -EBUSY;
                        goto out;
                }
                if (!cxl_ops->link_ok(afu->adapter, afu)) {
                        rc = -EIO;
                        goto out;
                }

                dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
                pr_devel_ratelimited("PSL purging... PSL_CNTL: 0x%016llx  PSL_DSISR: 0x%016llx\n", PSL_CNTL, dsisr);
                if (dsisr & CXL_PSL_DSISR_TRANS) {
                        dar = cxl_p2n_read(afu, CXL_PSL_DAR_An);
                        dev_notice(&afu->dev, "PSL purge terminating pending translation, DSISR: 0x%016llx, DAR: 0x%016llx\n", dsisr, dar);
                        cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_AE);
                } else if (dsisr) {
                        dev_notice(&afu->dev, "PSL purge acknowledging pending non-translation fault, DSISR: 0x%016llx\n", dsisr);
                        cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_A);
                } else {
                        cpu_relax();
                }
                PSL_CNTL = cxl_p1n_read(afu, CXL_PSL_SCNTL_An);
        };
        end = local_clock();
        pr_devel("PSL purged in %lld ns\n", end - start);

        cxl_p1n_write(afu, CXL_PSL_SCNTL_An,
                       PSL_CNTL & ~CXL_PSL_SCNTL_An_Pc);
out:
        trace_cxl_psl_ctrl_done(afu, CXL_PSL_SCNTL_An_Pc, rc);
        return rc;
}

static int spa_max_procs(int spa_size)
{
        /*
         * From the CAIA:
         *    end_of_SPA_area = SPA_Base + ((n+4) * 128) + (( ((n*8) + 127) >> 7) * 128) + 255
         * Most of that junk is really just an overly-complicated way of saying
         * the last 256 bytes are __aligned(128), so it's really:
         *    end_of_SPA_area = end_of_PSL_queue_area + __aligned(128) 255
         * and
         *    end_of_PSL_queue_area = SPA_Base + ((n+4) * 128) + (n*8) - 1
         * so
         *    sizeof(SPA) = ((n+4) * 128) + (n*8) + __aligned(128) 256
         * Ignore the alignment (which is safe in this case as long as we are
         * careful with our rounding) and solve for n:
         */
        return ((spa_size / 8) - 96) / 17;
}

int cxl_alloc_spa(struct cxl_afu *afu)
{
        unsigned spa_size;

        /* Work out how many pages to allocate */
        afu->native->spa_order = -1;
        do {
                afu->native->spa_order++;
                spa_size = (1 << afu->native->spa_order) * PAGE_SIZE;

                if (spa_size > 0x100000) {
                        dev_warn(&afu->dev, "num_of_processes too large for the SPA, limiting to %i (0x%x)\n",
                                        afu->native->spa_max_procs, afu->native->spa_size);
                        afu->num_procs = afu->native->spa_max_procs;
                        break;
                }

                afu->native->spa_size = spa_size;
                afu->native->spa_max_procs = spa_max_procs(afu->native->spa_size);
        } while (afu->native->spa_max_procs < afu->num_procs);

        if (!(afu->native->spa = (struct cxl_process_element *)
              __get_free_pages(GFP_KERNEL | __GFP_ZERO, afu->native->spa_order))) {
                pr_err("cxl_alloc_spa: Unable to allocate scheduled process area\n");
                return -ENOMEM;
        }
        pr_devel("spa pages: %i afu->spa_max_procs: %i   afu->num_procs: %i\n",
                 1<<afu->native->spa_order, afu->native->spa_max_procs, afu->num_procs);

        return 0;
}

static void attach_spa(struct cxl_afu *afu)
{
        u64 spap;

        afu->native->sw_command_status = (__be64 *)((char *)afu->native->spa +
                                            ((afu->native->spa_max_procs + 3) * 128));

        spap = virt_to_phys(afu->native->spa) & CXL_PSL_SPAP_Addr;
        spap |= ((afu->native->spa_size >> (12 - CXL_PSL_SPAP_Size_Shift)) - 1) & CXL_PSL_SPAP_Size;
        spap |= CXL_PSL_SPAP_V;
        pr_devel("cxl: SPA allocated at 0x%p. Max processes: %i, sw_command_status: 0x%p CXL_PSL_SPAP_An=0x%016llx\n",
                afu->native->spa, afu->native->spa_max_procs,
                afu->native->sw_command_status, spap);
        cxl_p1n_write(afu, CXL_PSL_SPAP_An, spap);
}

static inline void detach_spa(struct cxl_afu *afu)
{
        cxl_p1n_write(afu, CXL_PSL_SPAP_An, 0);
}

void cxl_release_spa(struct cxl_afu *afu)
{
        if (afu->native->spa) {
                free_pages((unsigned long) afu->native->spa,
                        afu->native->spa_order);
                afu->native->spa = NULL;
        }
}

int cxl_tlb_slb_invalidate(struct cxl *adapter)
{
        unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);

        pr_devel("CXL adapter wide TLBIA & SLBIA\n");

        cxl_p1_write(adapter, CXL_PSL_AFUSEL, CXL_PSL_AFUSEL_A);

        cxl_p1_write(adapter, CXL_PSL_TLBIA, CXL_TLB_SLB_IQ_ALL);
        while (cxl_p1_read(adapter, CXL_PSL_TLBIA) & CXL_TLB_SLB_P) {
                if (time_after_eq(jiffies, timeout)) {
                        dev_warn(&adapter->dev, "WARNING: CXL adapter wide TLBIA timed out!\n");
                        return -EBUSY;
                }
                if (!cxl_ops->link_ok(adapter, NULL))
                        return -EIO;
                cpu_relax();
        }

        cxl_p1_write(adapter, CXL_PSL_SLBIA, CXL_TLB_SLB_IQ_ALL);
        while (cxl_p1_read(adapter, CXL_PSL_SLBIA) & CXL_TLB_SLB_P) {
                if (time_after_eq(jiffies, timeout)) {
                        dev_warn(&adapter->dev, "WARNING: CXL adapter wide SLBIA timed out!\n");
                        return -EBUSY;
                }
                if (!cxl_ops->link_ok(adapter, NULL))
                        return -EIO;
                cpu_relax();
        }
        return 0;
}

static int cxl_write_sstp(struct cxl_afu *afu, u64 sstp0, u64 sstp1)
{
        int rc;

        /* 1. Disable SSTP by writing 0 to SSTP1[V] */
        cxl_p2n_write(afu, CXL_SSTP1_An, 0);

        /* 2. Invalidate all SLB entries */
        if ((rc = cxl_afu_slbia(afu)))
                return rc;

        /* 3. Set SSTP0_An */
        cxl_p2n_write(afu, CXL_SSTP0_An, sstp0);

        /* 4. Set SSTP1_An */
        cxl_p2n_write(afu, CXL_SSTP1_An, sstp1);

        return 0;
}

/* Using per slice version may improve performance here. (ie. SLBIA_An) */
static void slb_invalid(struct cxl_context *ctx)
{
        struct cxl *adapter = ctx->afu->adapter;
        u64 slbia;

        WARN_ON(!mutex_is_locked(&ctx->afu->native->spa_mutex));

        cxl_p1_write(adapter, CXL_PSL_LBISEL,
                        ((u64)be32_to_cpu(ctx->elem->common.pid) << 32) |
                        be32_to_cpu(ctx->elem->lpid));
        cxl_p1_write(adapter, CXL_PSL_SLBIA, CXL_TLB_SLB_IQ_LPIDPID);

        while (1) {
                if (!cxl_ops->link_ok(adapter, NULL))
                        break;
                slbia = cxl_p1_read(adapter, CXL_PSL_SLBIA);
                if (!(slbia & CXL_TLB_SLB_P))
                        break;
                cpu_relax();
        }
}

static int do_process_element_cmd(struct cxl_context *ctx,
                                  u64 cmd, u64 pe_state)
{
        u64 state;
        unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
        int rc = 0;

        trace_cxl_llcmd(ctx, cmd);

        WARN_ON(!ctx->afu->enabled);

        ctx->elem->software_state = cpu_to_be32(pe_state);
        smp_wmb();
        *(ctx->afu->native->sw_command_status) = cpu_to_be64(cmd | 0 | ctx->pe);
        smp_mb();
        cxl_p1n_write(ctx->afu, CXL_PSL_LLCMD_An, cmd | ctx->pe);
        while (1) {
                if (time_after_eq(jiffies, timeout)) {
                        dev_warn(&ctx->afu->dev, "WARNING: Process Element Command timed out!\n");
                        rc = -EBUSY;
                        goto out;
                }
                if (!cxl_ops->link_ok(ctx->afu->adapter, ctx->afu)) {
                        dev_warn(&ctx->afu->dev, "WARNING: Device link down, aborting Process Element Command!\n");
                        rc = -EIO;
                        goto out;
                }
                state = be64_to_cpup(ctx->afu->native->sw_command_status);
                if (state == ~0ULL) {
                        pr_err("cxl: Error adding process element to AFU\n");
                        rc = -1;
                        goto out;
                }
                if ((state & (CXL_SPA_SW_CMD_MASK | CXL_SPA_SW_STATE_MASK  | CXL_SPA_SW_LINK_MASK)) ==
                    (cmd | (cmd >> 16) | ctx->pe))
                        break;
                /*
                 * The command won't finish in the PSL if there are
                 * outstanding DSIs.  Hence we need to yield here in
                 * case there are outstanding DSIs that we need to
                 * service.  Tuning possiblity: we could wait for a
                 * while before sched
                 */
                schedule();

        }
out:
        trace_cxl_llcmd_done(ctx, cmd, rc);
        return rc;
}

static int add_process_element(struct cxl_context *ctx)
{
        int rc = 0;

        mutex_lock(&ctx->afu->native->spa_mutex);
        pr_devel("%s Adding pe: %i started\n", __func__, ctx->pe);
        if (!(rc = do_process_element_cmd(ctx, CXL_SPA_SW_CMD_ADD, CXL_PE_SOFTWARE_STATE_V)))
                ctx->pe_inserted = true;
        pr_devel("%s Adding pe: %i finished\n", __func__, ctx->pe);
        mutex_unlock(&ctx->afu->native->spa_mutex);
        return rc;
}

static int terminate_process_element(struct cxl_context *ctx)
{
        int rc = 0;

        /* fast path terminate if it's already invalid */
        if (!(ctx->elem->software_state & cpu_to_be32(CXL_PE_SOFTWARE_STATE_V)))
                return rc;

        mutex_lock(&ctx->afu->native->spa_mutex);
        pr_devel("%s Terminate pe: %i started\n", __func__, ctx->pe);
        /* We could be asked to terminate when the hw is down. That
         * should always succeed: it's not running if the hw has gone
         * away and is being reset.
         */
        if (cxl_ops->link_ok(ctx->afu->adapter, ctx->afu))
                rc = do_process_element_cmd(ctx, CXL_SPA_SW_CMD_TERMINATE,
                                            CXL_PE_SOFTWARE_STATE_V | CXL_PE_SOFTWARE_STATE_T);
        ctx->elem->software_state = 0;  /* Remove Valid bit */
        pr_devel("%s Terminate pe: %i finished\n", __func__, ctx->pe);
        mutex_unlock(&ctx->afu->native->spa_mutex);
        return rc;
}

static int remove_process_element(struct cxl_context *ctx)
{
        int rc = 0;

        mutex_lock(&ctx->afu->native->spa_mutex);
        pr_devel("%s Remove pe: %i started\n", __func__, ctx->pe);

        /* We could be asked to remove when the hw is down. Again, if
         * the hw is down, the PE is gone, so we succeed.
         */
        if (cxl_ops->link_ok(ctx->afu->adapter, ctx->afu))
                rc = do_process_element_cmd(ctx, CXL_SPA_SW_CMD_REMOVE, 0);

        if (!rc)
                ctx->pe_inserted = false;
        slb_invalid(ctx);
        pr_devel("%s Remove pe: %i finished\n", __func__, ctx->pe);
        mutex_unlock(&ctx->afu->native->spa_mutex);

        return rc;
}

void cxl_assign_psn_space(struct cxl_context *ctx)
{
        if (!ctx->afu->pp_size || ctx->master) {
                ctx->psn_phys = ctx->afu->psn_phys;
                ctx->psn_size = ctx->afu->adapter->ps_size;
        } else {
                ctx->psn_phys = ctx->afu->psn_phys +
                        (ctx->afu->native->pp_offset + ctx->afu->pp_size * ctx->pe);
                ctx->psn_size = ctx->afu->pp_size;
        }
}

static int activate_afu_directed(struct cxl_afu *afu)
{
        int rc;

        dev_info(&afu->dev, "Activating AFU directed mode\n");

        afu->num_procs = afu->max_procs_virtualised;
        if (afu->native->spa == NULL) {
                if (cxl_alloc_spa(afu))
                        return -ENOMEM;
        }
        attach_spa(afu);

        cxl_p1n_write(afu, CXL_PSL_SCNTL_An, CXL_PSL_SCNTL_An_PM_AFU);
        cxl_p1n_write(afu, CXL_PSL_AMOR_An, 0xFFFFFFFFFFFFFFFFULL);
        cxl_p1n_write(afu, CXL_PSL_ID_An, CXL_PSL_ID_An_F | CXL_PSL_ID_An_L);

        afu->current_mode = CXL_MODE_DIRECTED;

        if ((rc = cxl_chardev_m_afu_add(afu)))
                return rc;

        if ((rc = cxl_sysfs_afu_m_add(afu)))
                goto err;

        if ((rc = cxl_chardev_s_afu_add(afu)))
                goto err1;

        return 0;
err1:
        cxl_sysfs_afu_m_remove(afu);
err:
        cxl_chardev_afu_remove(afu);
        return rc;
}

#ifdef CONFIG_CPU_LITTLE_ENDIAN
#define set_endian(sr) ((sr) |= CXL_PSL_SR_An_LE)
#else
#define set_endian(sr) ((sr) &= ~(CXL_PSL_SR_An_LE))
#endif

static u64 calculate_sr(struct cxl_context *ctx)
{
        u64 sr = 0;

        set_endian(sr);
        if (ctx->master)
                sr |= CXL_PSL_SR_An_MP;
        if (mfspr(SPRN_LPCR) & LPCR_TC)
                sr |= CXL_PSL_SR_An_TC;
        if (ctx->kernel) {
                if (!ctx->real_mode)
                        sr |= CXL_PSL_SR_An_R;
                sr |= (mfmsr() & MSR_SF) | CXL_PSL_SR_An_HV;
        } else {
                sr |= CXL_PSL_SR_An_PR | CXL_PSL_SR_An_R;
                sr &= ~(CXL_PSL_SR_An_HV);
                if (!test_tsk_thread_flag(current, TIF_32BIT))
                        sr |= CXL_PSL_SR_An_SF;
        }
        return sr;
}

static void update_ivtes_directed(struct cxl_context *ctx)
{
        bool need_update = (ctx->status == STARTED);
        int r;

        if (need_update) {
                WARN_ON(terminate_process_element(ctx));
                WARN_ON(remove_process_element(ctx));
        }

        for (r = 0; r < CXL_IRQ_RANGES; r++) {
                ctx->elem->ivte_offsets[r] = cpu_to_be16(ctx->irqs.offset[r]);
                ctx->elem->ivte_ranges[r] = cpu_to_be16(ctx->irqs.range[r]);
        }

        /*
         * Theoretically we could use the update llcmd, instead of a
         * terminate/remove/add (or if an atomic update was required we could
         * do a suspend/update/resume), however it seems there might be issues
         * with the update llcmd on some cards (including those using an XSL on
         * an ASIC) so for now it's safest to go with the commands that are
         * known to work. In the future if we come across a situation where the
         * card may be performing transactions using the same PE while we are
         * doing this update we might need to revisit this.
         */
        if (need_update)
                WARN_ON(add_process_element(ctx));
}

static int attach_afu_directed(struct cxl_context *ctx, u64 wed, u64 amr)
{
        u32 pid;
        int result;

        cxl_assign_psn_space(ctx);

        ctx->elem->ctxtime = 0; /* disable */
        ctx->elem->lpid = cpu_to_be32(mfspr(SPRN_LPID));
        ctx->elem->haurp = 0; /* disable */
        ctx->elem->sdr = cpu_to_be64(mfspr(SPRN_SDR1));

        pid = current->pid;
        if (ctx->kernel)
                pid = 0;
        ctx->elem->common.tid = 0;
        ctx->elem->common.pid = cpu_to_be32(pid);

        ctx->elem->sr = cpu_to_be64(calculate_sr(ctx));

        ctx->elem->common.csrp = 0; /* disable */
        ctx->elem->common.aurp0 = 0; /* disable */
        ctx->elem->common.aurp1 = 0; /* disable */

        cxl_prefault(ctx, wed);

        ctx->elem->common.sstp0 = cpu_to_be64(ctx->sstp0);
        ctx->elem->common.sstp1 = cpu_to_be64(ctx->sstp1);

        /*
         * Ensure we have the multiplexed PSL interrupt set up to take faults
         * for kernel contexts that may not have allocated any AFU IRQs at all:
         */
        if (ctx->irqs.range[0] == 0) {
                ctx->irqs.offset[0] = ctx->afu->native->psl_hwirq;
                ctx->irqs.range[0] = 1;
        }

        update_ivtes_directed(ctx);

        ctx->elem->common.amr = cpu_to_be64(amr);
        ctx->elem->common.wed = cpu_to_be64(wed);

        /* first guy needs to enable */
        if ((result = cxl_ops->afu_check_and_enable(ctx->afu)))
                return result;

        return add_process_element(ctx);
}

static int deactivate_afu_directed(struct cxl_afu *afu)
{
        dev_info(&afu->dev, "Deactivating AFU directed mode\n");

        afu->current_mode = 0;
        afu->num_procs = 0;

        cxl_sysfs_afu_m_remove(afu);
        cxl_chardev_afu_remove(afu);

        /*
         * The CAIA section 2.2.1 indicates that the procedure for starting and
         * stopping an AFU in AFU directed mode is AFU specific, which is not
         * ideal since this code is generic and with one exception has no
         * knowledge of the AFU. This is in contrast to the procedure for
         * disabling a dedicated process AFU, which is documented to just
         * require a reset. The architecture does indicate that both an AFU
         * reset and an AFU disable should result in the AFU being disabled and
         * we do both followed by a PSL purge for safety.
         *
         * Notably we used to have some issues with the disable sequence on PSL
         * cards, which is why we ended up using this heavy weight procedure in
         * the first place, however a bug was discovered that had rendered the
         * disable operation ineffective, so it is conceivable that was the
         * sole explanation for those difficulties. Careful regression testing
         * is recommended if anyone attempts to remove or reorder these
         * operations.
         *
         * The XSL on the Mellanox CX4 behaves a little differently from the
         * PSL based cards and will time out an AFU reset if the AFU is still
         * enabled. That card is special in that we do have a means to identify
         * it from this code, so in that case we skip the reset and just use a
         * disable/purge to avoid the timeout and corresponding noise in the
         * kernel log.
         */
        if (afu->adapter->native->sl_ops->needs_reset_before_disable)
                cxl_ops->afu_reset(afu);
        cxl_afu_disable(afu);
        cxl_psl_purge(afu);

        return 0;
}

static int activate_dedicated_process(struct cxl_afu *afu)
{
        dev_info(&afu->dev, "Activating dedicated process mode\n");

        cxl_p1n_write(afu, CXL_PSL_SCNTL_An, CXL_PSL_SCNTL_An_PM_Process);

        cxl_p1n_write(afu, CXL_PSL_CtxTime_An, 0); /* disable */
        cxl_p1n_write(afu, CXL_PSL_SPAP_An, 0);    /* disable */
        cxl_p1n_write(afu, CXL_PSL_AMOR_An, 0xFFFFFFFFFFFFFFFFULL);
        cxl_p1n_write(afu, CXL_PSL_LPID_An, mfspr(SPRN_LPID));
        cxl_p1n_write(afu, CXL_HAURP_An, 0);       /* disable */
        cxl_p1n_write(afu, CXL_PSL_SDR_An, mfspr(SPRN_SDR1));

        cxl_p2n_write(afu, CXL_CSRP_An, 0);        /* disable */
        cxl_p2n_write(afu, CXL_AURP0_An, 0);       /* disable */
        cxl_p2n_write(afu, CXL_AURP1_An, 0);       /* disable */

        afu->current_mode = CXL_MODE_DEDICATED;
        afu->num_procs = 1;

        return cxl_chardev_d_afu_add(afu);
}

static void update_ivtes_dedicated(struct cxl_context *ctx)
{
        struct cxl_afu *afu = ctx->afu;

        cxl_p1n_write(afu, CXL_PSL_IVTE_Offset_An,
                       (((u64)ctx->irqs.offset[0] & 0xffff) << 48) |
                       (((u64)ctx->irqs.offset[1] & 0xffff) << 32) |
                       (((u64)ctx->irqs.offset[2] & 0xffff) << 16) |
                        ((u64)ctx->irqs.offset[3] & 0xffff));
        cxl_p1n_write(afu, CXL_PSL_IVTE_Limit_An, (u64)
                       (((u64)ctx->irqs.range[0] & 0xffff) << 48) |
                       (((u64)ctx->irqs.range[1] & 0xffff) << 32) |
                       (((u64)ctx->irqs.range[2] & 0xffff) << 16) |
                        ((u64)ctx->irqs.range[3] & 0xffff));
}

static int attach_dedicated(struct cxl_context *ctx, u64 wed, u64 amr)
{
        struct cxl_afu *afu = ctx->afu;
        u64 pid;
        int rc;

        pid = (u64)current->pid << 32;
        if (ctx->kernel)
                pid = 0;
        cxl_p2n_write(afu, CXL_PSL_PID_TID_An, pid);

        cxl_p1n_write(afu, CXL_PSL_SR_An, calculate_sr(ctx));

        if ((rc = cxl_write_sstp(afu, ctx->sstp0, ctx->sstp1)))
                return rc;

        cxl_prefault(ctx, wed);

        update_ivtes_dedicated(ctx);

        cxl_p2n_write(afu, CXL_PSL_AMR_An, amr);

        /* master only context for dedicated */
        cxl_assign_psn_space(ctx);

        if ((rc = cxl_ops->afu_reset(afu)))
                return rc;

        cxl_p2n_write(afu, CXL_PSL_WED_An, wed);

        return afu_enable(afu);
}

static int deactivate_dedicated_process(struct cxl_afu *afu)
{
        dev_info(&afu->dev, "Deactivating dedicated process mode\n");

        afu->current_mode = 0;
        afu->num_procs = 0;

        cxl_chardev_afu_remove(afu);

        return 0;
}

static int native_afu_deactivate_mode(struct cxl_afu *afu, int mode)
{
        if (mode == CXL_MODE_DIRECTED)
                return deactivate_afu_directed(afu);
        if (mode == CXL_MODE_DEDICATED)
                return deactivate_dedicated_process(afu);
        return 0;
}

static int native_afu_activate_mode(struct cxl_afu *afu, int mode)
{
        if (!mode)
                return 0;
        if (!(mode & afu->modes_supported))
                return -EINVAL;

        if (!cxl_ops->link_ok(afu->adapter, afu)) {
                WARN(1, "Device link is down, refusing to activate!\n");
                return -EIO;
        }

        if (mode == CXL_MODE_DIRECTED)
                return activate_afu_directed(afu);
        if (mode == CXL_MODE_DEDICATED)
                return activate_dedicated_process(afu);

        return -EINVAL;
}

static int native_attach_process(struct cxl_context *ctx, bool kernel,
                                u64 wed, u64 amr)
{
        if (!cxl_ops->link_ok(ctx->afu->adapter, ctx->afu)) {
                WARN(1, "Device link is down, refusing to attach process!\n");
                return -EIO;
        }

        ctx->kernel = kernel;
        if (ctx->afu->current_mode == CXL_MODE_DIRECTED)
                return attach_afu_directed(ctx, wed, amr);

        if (ctx->afu->current_mode == CXL_MODE_DEDICATED)
                return attach_dedicated(ctx, wed, amr);

        return -EINVAL;
}

static inline int detach_process_native_dedicated(struct cxl_context *ctx)
{
        /*
         * The CAIA section 2.1.1 indicates that we need to do an AFU reset to
         * stop the AFU in dedicated mode (we therefore do not make that
         * optional like we do in the afu directed path). It does not indicate
         * that we need to do an explicit disable (which should occur
         * implicitly as part of the reset) or purge, but we do these as well
         * to be on the safe side.
         *
         * Notably we used to have some issues with the disable sequence
         * (before the sequence was spelled out in the architecture) which is
         * why we were so heavy weight in the first place, however a bug was
         * discovered that had rendered the disable operation ineffective, so
         * it is conceivable that was the sole explanation for those
         * difficulties. Point is, we should be careful and do some regression
         * testing if we ever attempt to remove any part of this procedure.
         */
        cxl_ops->afu_reset(ctx->afu);
        cxl_afu_disable(ctx->afu);
        cxl_psl_purge(ctx->afu);
        return 0;
}

static void native_update_ivtes(struct cxl_context *ctx)
{
        if (ctx->afu->current_mode == CXL_MODE_DIRECTED)
                return update_ivtes_directed(ctx);
        if (ctx->afu->current_mode == CXL_MODE_DEDICATED)
                return update_ivtes_dedicated(ctx);
        WARN(1, "native_update_ivtes: Bad mode\n");
}

static inline int detach_process_native_afu_directed(struct cxl_context *ctx)
{
        if (!ctx->pe_inserted)
                return 0;
        if (terminate_process_element(ctx))
                return -1;
        if (remove_process_element(ctx))
                return -1;

        return 0;
}

static int native_detach_process(struct cxl_context *ctx)
{
        trace_cxl_detach(ctx);

        if (ctx->afu->current_mode == CXL_MODE_DEDICATED)
                return detach_process_native_dedicated(ctx);

        return detach_process_native_afu_directed(ctx);
}

static int native_get_irq_info(struct cxl_afu *afu, struct cxl_irq_info *info)
{
        u64 pidtid;

        /* If the adapter has gone away, we can't get any meaningful
         * information.
         */
        if (!cxl_ops->link_ok(afu->adapter, afu))
                return -EIO;

        info->dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
        info->dar = cxl_p2n_read(afu, CXL_PSL_DAR_An);
        info->dsr = cxl_p2n_read(afu, CXL_PSL_DSR_An);
        pidtid = cxl_p2n_read(afu, CXL_PSL_PID_TID_An);
        info->pid = pidtid >> 32;
        info->tid = pidtid & 0xffffffff;
        info->afu_err = cxl_p2n_read(afu, CXL_AFU_ERR_An);
        info->errstat = cxl_p2n_read(afu, CXL_PSL_ErrStat_An);
        info->proc_handle = 0;

        return 0;
}

void cxl_native_psl_irq_dump_regs(struct cxl_context *ctx)
{
        u64 fir1, fir2, fir_slice, serr, afu_debug;

        fir1 = cxl_p1_read(ctx->afu->adapter, CXL_PSL_FIR1);
        fir2 = cxl_p1_read(ctx->afu->adapter, CXL_PSL_FIR2);
        fir_slice = cxl_p1n_read(ctx->afu, CXL_PSL_FIR_SLICE_An);
        afu_debug = cxl_p1n_read(ctx->afu, CXL_AFU_DEBUG_An);

        dev_crit(&ctx->afu->dev, "PSL_FIR1: 0x%016llx\n", fir1);
        dev_crit(&ctx->afu->dev, "PSL_FIR2: 0x%016llx\n", fir2);
        if (ctx->afu->adapter->native->sl_ops->register_serr_irq) {
                serr = cxl_p1n_read(ctx->afu, CXL_PSL_SERR_An);
                cxl_afu_decode_psl_serr(ctx->afu, serr);
        }
        dev_crit(&ctx->afu->dev, "PSL_FIR_SLICE_An: 0x%016llx\n", fir_slice);
        dev_crit(&ctx->afu->dev, "CXL_PSL_AFU_DEBUG_An: 0x%016llx\n", afu_debug);
}

static irqreturn_t native_handle_psl_slice_error(struct cxl_context *ctx,
                                                u64 dsisr, u64 errstat)
{

        dev_crit(&ctx->afu->dev, "PSL ERROR STATUS: 0x%016llx\n", errstat);

        if (ctx->afu->adapter->native->sl_ops->psl_irq_dump_registers)
                ctx->afu->adapter->native->sl_ops->psl_irq_dump_registers(ctx);

        if (ctx->afu->adapter->native->sl_ops->debugfs_stop_trace) {
                dev_crit(&ctx->afu->dev, "STOPPING CXL TRACE\n");
                ctx->afu->adapter->native->sl_ops->debugfs_stop_trace(ctx->afu->adapter);
        }

        return cxl_ops->ack_irq(ctx, 0, errstat);
}

static irqreturn_t fail_psl_irq(struct cxl_afu *afu, struct cxl_irq_info *irq_info)
{
        if (irq_info->dsisr & CXL_PSL_DSISR_TRANS)
                cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_AE);
        else
                cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_A);

        return IRQ_HANDLED;
}

static irqreturn_t native_irq_multiplexed(int irq, void *data)
{
        struct cxl_afu *afu = data;
        struct cxl_context *ctx;
        struct cxl_irq_info irq_info;
        int ph = cxl_p2n_read(afu, CXL_PSL_PEHandle_An) & 0xffff;
        int ret;

        if ((ret = native_get_irq_info(afu, &irq_info))) {
                WARN(1, "Unable to get CXL IRQ Info: %i\n", ret);
                return fail_psl_irq(afu, &irq_info);
        }

        rcu_read_lock();
        ctx = idr_find(&afu->contexts_idr, ph);
        if (ctx) {
                ret = cxl_irq(irq, ctx, &irq_info);
                rcu_read_unlock();
                return ret;
        }
        rcu_read_unlock();

        WARN(1, "Unable to demultiplex CXL PSL IRQ for PE %i DSISR %016llx DAR"
                " %016llx\n(Possible AFU HW issue - was a term/remove acked"
                " with outstanding transactions?)\n", ph, irq_info.dsisr,
                irq_info.dar);
        return fail_psl_irq(afu, &irq_info);
}

void native_irq_wait(struct cxl_context *ctx)
{
        u64 dsisr;
        int timeout = 1000;
        int ph;

        /*
         * Wait until no further interrupts are presented by the PSL
         * for this context.
         */
        while (timeout--) {
                ph = cxl_p2n_read(ctx->afu, CXL_PSL_PEHandle_An) & 0xffff;
                if (ph != ctx->pe)
                        return;
                dsisr = cxl_p2n_read(ctx->afu, CXL_PSL_DSISR_An);
                if ((dsisr & CXL_PSL_DSISR_PENDING) == 0)
                        return;
                /*
                 * We are waiting for the workqueue to process our
                 * irq, so need to let that run here.
                 */
                msleep(1);
        }

        dev_warn(&ctx->afu->dev, "WARNING: waiting on DSI for PE %i"
                 " DSISR %016llx!\n", ph, dsisr);
        return;
}

static irqreturn_t native_slice_irq_err(int irq, void *data)
{
        struct cxl_afu *afu = data;
        u64 fir_slice, errstat, serr, afu_debug, afu_error, dsisr;

        /*
         * slice err interrupt is only used with full PSL (no XSL)
         */
        serr = cxl_p1n_read(afu, CXL_PSL_SERR_An);
        fir_slice = cxl_p1n_read(afu, CXL_PSL_FIR_SLICE_An);
        errstat = cxl_p2n_read(afu, CXL_PSL_ErrStat_An);
        afu_debug = cxl_p1n_read(afu, CXL_AFU_DEBUG_An);
        afu_error = cxl_p2n_read(afu, CXL_AFU_ERR_An);
        dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
        cxl_afu_decode_psl_serr(afu, serr);
        dev_crit(&afu->dev, "PSL_FIR_SLICE_An: 0x%016llx\n", fir_slice);
        dev_crit(&afu->dev, "CXL_PSL_ErrStat_An: 0x%016llx\n", errstat);
        dev_crit(&afu->dev, "CXL_PSL_AFU_DEBUG_An: 0x%016llx\n", afu_debug);
        dev_crit(&afu->dev, "AFU_ERR_An: 0x%.16llx\n", afu_error);
        dev_crit(&afu->dev, "PSL_DSISR_An: 0x%.16llx\n", dsisr);

        cxl_p1n_write(afu, CXL_PSL_SERR_An, serr);

        return IRQ_HANDLED;
}

void cxl_native_err_irq_dump_regs(struct cxl *adapter)
{
        u64 fir1, fir2;

        fir1 = cxl_p1_read(adapter, CXL_PSL_FIR1);
        fir2 = cxl_p1_read(adapter, CXL_PSL_FIR2);

        dev_crit(&adapter->dev, "PSL_FIR1: 0x%016llx\nPSL_FIR2: 0x%016llx\n", fir1, fir2);
}

static irqreturn_t native_irq_err(int irq, void *data)
{
        struct cxl *adapter = data;
        u64 err_ivte;

        WARN(1, "CXL ERROR interrupt %i\n", irq);

        err_ivte = cxl_p1_read(adapter, CXL_PSL_ErrIVTE);
        dev_crit(&adapter->dev, "PSL_ErrIVTE: 0x%016llx\n", err_ivte);

        if (adapter->native->sl_ops->debugfs_stop_trace) {
                dev_crit(&adapter->dev, "STOPPING CXL TRACE\n");
                adapter->native->sl_ops->debugfs_stop_trace(adapter);
        }

        if (adapter->native->sl_ops->err_irq_dump_registers)
                adapter->native->sl_ops->err_irq_dump_registers(adapter);

        return IRQ_HANDLED;
}

int cxl_native_register_psl_err_irq(struct cxl *adapter)
{
        int rc;

        adapter->irq_name = kasprintf(GFP_KERNEL, "cxl-%s-err",
                                      dev_name(&adapter->dev));
        if (!adapter->irq_name)
                return -ENOMEM;

        if ((rc = cxl_register_one_irq(adapter, native_irq_err, adapter,
                                       &adapter->native->err_hwirq,
                                       &adapter->native->err_virq,
                                       adapter->irq_name))) {
                kfree(adapter->irq_name);
                adapter->irq_name = NULL;
                return rc;
        }

        cxl_p1_write(adapter, CXL_PSL_ErrIVTE, adapter->native->err_hwirq & 0xffff);

        return 0;
}

void cxl_native_release_psl_err_irq(struct cxl *adapter)
{
        if (adapter->native->err_virq != irq_find_mapping(NULL, adapter->native->err_hwirq))
                return;

        cxl_p1_write(adapter, CXL_PSL_ErrIVTE, 0x0000000000000000);
        cxl_unmap_irq(adapter->native->err_virq, adapter);
        cxl_ops->release_one_irq(adapter, adapter->native->err_hwirq);
        kfree(adapter->irq_name);
}

int cxl_native_register_serr_irq(struct cxl_afu *afu)
{
        u64 serr;
        int rc;

        afu->err_irq_name = kasprintf(GFP_KERNEL, "cxl-%s-err",
                                      dev_name(&afu->dev));
        if (!afu->err_irq_name)
                return -ENOMEM;

        if ((rc = cxl_register_one_irq(afu->adapter, native_slice_irq_err, afu,
                                       &afu->serr_hwirq,
                                       &afu->serr_virq, afu->err_irq_name))) {
                kfree(afu->err_irq_name);
                afu->err_irq_name = NULL;
                return rc;
        }

        serr = cxl_p1n_read(afu, CXL_PSL_SERR_An);
        serr = (serr & 0x00ffffffffff0000ULL) | (afu->serr_hwirq & 0xffff);
        cxl_p1n_write(afu, CXL_PSL_SERR_An, serr);

        return 0;
}

void cxl_native_release_serr_irq(struct cxl_afu *afu)
{
        if (afu->serr_virq != irq_find_mapping(NULL, afu->serr_hwirq))
                return;

        cxl_p1n_write(afu, CXL_PSL_SERR_An, 0x0000000000000000);
        cxl_unmap_irq(afu->serr_virq, afu);
        cxl_ops->release_one_irq(afu->adapter, afu->serr_hwirq);
        kfree(afu->err_irq_name);
}

int cxl_native_register_psl_irq(struct cxl_afu *afu)
{
        int rc;

        afu->psl_irq_name = kasprintf(GFP_KERNEL, "cxl-%s",
                                      dev_name(&afu->dev));
        if (!afu->psl_irq_name)
                return -ENOMEM;

        if ((rc = cxl_register_one_irq(afu->adapter, native_irq_multiplexed,
                                    afu, &afu->native->psl_hwirq, &afu->native->psl_virq,
                                    afu->psl_irq_name))) {
                kfree(afu->psl_irq_name);
                afu->psl_irq_name = NULL;
        }
        return rc;
}

void cxl_native_release_psl_irq(struct cxl_afu *afu)
{
        if (afu->native->psl_virq != irq_find_mapping(NULL, afu->native->psl_hwirq))
                return;

        cxl_unmap_irq(afu->native->psl_virq, afu);
        cxl_ops->release_one_irq(afu->adapter, afu->native->psl_hwirq);
        kfree(afu->psl_irq_name);
}

static void recover_psl_err(struct cxl_afu *afu, u64 errstat)
{
        u64 dsisr;

        pr_devel("RECOVERING FROM PSL ERROR... (0x%016llx)\n", errstat);

        /* Clear PSL_DSISR[PE] */
        dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
        cxl_p2n_write(afu, CXL_PSL_DSISR_An, dsisr & ~CXL_PSL_DSISR_An_PE);

        /* Write 1s to clear error status bits */
        cxl_p2n_write(afu, CXL_PSL_ErrStat_An, errstat);
}

static int native_ack_irq(struct cxl_context *ctx, u64 tfc, u64 psl_reset_mask)
{
        trace_cxl_psl_irq_ack(ctx, tfc);
        if (tfc)
                cxl_p2n_write(ctx->afu, CXL_PSL_TFC_An, tfc);
        if (psl_reset_mask)
                recover_psl_err(ctx->afu, psl_reset_mask);

        return 0;
}

int cxl_check_error(struct cxl_afu *afu)
{
        return (cxl_p1n_read(afu, CXL_PSL_SCNTL_An) == ~0ULL);
}

static bool native_support_attributes(const char *attr_name,
                                      enum cxl_attrs type)
{
        return true;
}

static int native_afu_cr_read64(struct cxl_afu *afu, int cr, u64 off, u64 *out)
{
        if (unlikely(!cxl_ops->link_ok(afu->adapter, afu)))
                return -EIO;
        if (unlikely(off >= afu->crs_len))
                return -ERANGE;
        *out = in_le64(afu->native->afu_desc_mmio + afu->crs_offset +
                (cr * afu->crs_len) + off);
        return 0;
}

static int native_afu_cr_read32(struct cxl_afu *afu, int cr, u64 off, u32 *out)
{
        if (unlikely(!cxl_ops->link_ok(afu->adapter, afu)))
                return -EIO;
        if (unlikely(off >= afu->crs_len))
                return -ERANGE;
        *out = in_le32(afu->native->afu_desc_mmio + afu->crs_offset +
                (cr * afu->crs_len) + off);
        return 0;
}

static int native_afu_cr_read16(struct cxl_afu *afu, int cr, u64 off, u16 *out)
{
        u64 aligned_off = off & ~0x3L;
        u32 val;
        int rc;

        rc = native_afu_cr_read32(afu, cr, aligned_off, &val);
        if (!rc)
                *out = (val >> ((off & 0x3) * 8)) & 0xffff;
        return rc;
}

static int native_afu_cr_read8(struct cxl_afu *afu, int cr, u64 off, u8 *out)
{
        u64 aligned_off = off & ~0x3L;
        u32 val;
        int rc;

        rc = native_afu_cr_read32(afu, cr, aligned_off, &val);
        if (!rc)
                *out = (val >> ((off & 0x3) * 8)) & 0xff;
        return rc;
}

static int native_afu_cr_write32(struct cxl_afu *afu, int cr, u64 off, u32 in)
{
        if (unlikely(!cxl_ops->link_ok(afu->adapter, afu)))
                return -EIO;
        if (unlikely(off >= afu->crs_len))
                return -ERANGE;
        out_le32(afu->native->afu_desc_mmio + afu->crs_offset +
                (cr * afu->crs_len) + off, in);
        return 0;
}

static int native_afu_cr_write16(struct cxl_afu *afu, int cr, u64 off, u16 in)
{
        u64 aligned_off = off & ~0x3L;
        u32 val32, mask, shift;
        int rc;

        rc = native_afu_cr_read32(afu, cr, aligned_off, &val32);
        if (rc)
                return rc;
        shift = (off & 0x3) * 8;
        WARN_ON(shift == 24);
        mask = 0xffff << shift;
        val32 = (val32 & ~mask) | (in << shift);

        rc = native_afu_cr_write32(afu, cr, aligned_off, val32);
        return rc;
}

static int native_afu_cr_write8(struct cxl_afu *afu, int cr, u64 off, u8 in)
{
        u64 aligned_off = off & ~0x3L;
        u32 val32, mask, shift;
        int rc;

        rc = native_afu_cr_read32(afu, cr, aligned_off, &val32);
        if (rc)
                return rc;
        shift = (off & 0x3) * 8;
        mask = 0xff << shift;
        val32 = (val32 & ~mask) | (in << shift);

        rc = native_afu_cr_write32(afu, cr, aligned_off, val32);
        return rc;
}

const struct cxl_backend_ops cxl_native_ops = {
        .module = THIS_MODULE,
        .adapter_reset = cxl_pci_reset,
        .alloc_one_irq = cxl_pci_alloc_one_irq,
        .release_one_irq = cxl_pci_release_one_irq,
        .alloc_irq_ranges = cxl_pci_alloc_irq_ranges,
        .release_irq_ranges = cxl_pci_release_irq_ranges,
        .setup_irq = cxl_pci_setup_irq,
        .handle_psl_slice_error = native_handle_psl_slice_error,
        .psl_interrupt = NULL,
        .ack_irq = native_ack_irq,
        .irq_wait = native_irq_wait,
        .attach_process = native_attach_process,
        .detach_process = native_detach_process,
        .update_ivtes = native_update_ivtes,
        .support_attributes = native_support_attributes,
        .link_ok = cxl_adapter_link_ok,
        .release_afu = cxl_pci_release_afu,
        .afu_read_err_buffer = cxl_pci_afu_read_err_buffer,
        .afu_check_and_enable = native_afu_check_and_enable,
        .afu_activate_mode = native_afu_activate_mode,
        .afu_deactivate_mode = native_afu_deactivate_mode,
        .afu_reset = native_afu_reset,
        .afu_cr_read8 = native_afu_cr_read8,
        .afu_cr_read16 = native_afu_cr_read16,
        .afu_cr_read32 = native_afu_cr_read32,
        .afu_cr_read64 = native_afu_cr_read64,
        .afu_cr_write8 = native_afu_cr_write8,
        .afu_cr_write16 = native_afu_cr_write16,
        .afu_cr_write32 = native_afu_cr_write32,
        .read_adapter_vpd = cxl_pci_read_adapter_vpd,
};