irqchip/gicv3: Remove disabling redistributor and group1 non-secure interrupts

[mirror_ubuntu-zesty-kernel.git] / drivers / irqchip / irq-gic-v3.c

/*
 * Copyright (C) 2013, 2014 ARM Limited, All Rights Reserved.
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#define pr_fmt(fmt)     "GICv3: " fmt

#include <linux/acpi.h>
#include <linux/cpu.h>
#include <linux/cpu_pm.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/percpu.h>
#include <linux/slab.h>

#include <linux/irqchip.h>
#include <linux/irqchip/arm-gic-common.h>
#include <linux/irqchip/arm-gic-v3.h>
#include <linux/irqchip/irq-partition-percpu.h>

#include <asm/cputype.h>
#include <asm/exception.h>
#include <asm/smp_plat.h>
#include <asm/virt.h>

#include "irq-gic-common.h"

struct redist_region {
        void __iomem            *redist_base;
        phys_addr_t             phys_base;
        bool                    single_redist;
};

struct gic_chip_data {
        struct fwnode_handle    *fwnode;
        void __iomem            *dist_base;
        struct redist_region    *redist_regions;
        struct rdists           rdists;
        struct irq_domain       *domain;
        u64                     redist_stride;
        u32                     nr_redist_regions;
        unsigned int            irq_nr;
        struct partition_desc   *ppi_descs[16];
};

static struct gic_chip_data gic_data __read_mostly;
static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;

static struct gic_kvm_info gic_v3_kvm_info;

#define gic_data_rdist()                (this_cpu_ptr(gic_data.rdists.rdist))
#define gic_data_rdist_rd_base()        (gic_data_rdist()->rd_base)
#define gic_data_rdist_sgi_base()       (gic_data_rdist_rd_base() + SZ_64K)

/* Our default, arbitrary priority value. Linux only uses one anyway. */
#define DEFAULT_PMR_VALUE       0xf0

static inline unsigned int gic_irq(struct irq_data *d)
{
        return d->hwirq;
}

static inline int gic_irq_in_rdist(struct irq_data *d)
{
        return gic_irq(d) < 32;
}

static inline void __iomem *gic_dist_base(struct irq_data *d)
{
        if (gic_irq_in_rdist(d))        /* SGI+PPI -> SGI_base for this CPU */
                return gic_data_rdist_sgi_base();

        if (d->hwirq <= 1023)           /* SPI -> dist_base */
                return gic_data.dist_base;

        return NULL;
}

static void gic_do_wait_for_rwp(void __iomem *base)
{
        u32 count = 1000000;    /* 1s! */

        while (readl_relaxed(base + GICD_CTLR) & GICD_CTLR_RWP) {
                count--;
                if (!count) {
                        pr_err_ratelimited("RWP timeout, gone fishing\n");
                        return;
                }
                cpu_relax();
                udelay(1);
        };
}

/* Wait for completion of a distributor change */
static void gic_dist_wait_for_rwp(void)
{
        gic_do_wait_for_rwp(gic_data.dist_base);
}

/* Wait for completion of a redistributor change */
static void gic_redist_wait_for_rwp(void)
{
        gic_do_wait_for_rwp(gic_data_rdist_rd_base());
}

#ifdef CONFIG_ARM64
static DEFINE_STATIC_KEY_FALSE(is_cavium_thunderx);

static u64 __maybe_unused gic_read_iar(void)
{
        if (static_branch_unlikely(&is_cavium_thunderx))
                return gic_read_iar_cavium_thunderx();
        else
                return gic_read_iar_common();
}
#endif

static void gic_enable_redist(bool enable)
{
        void __iomem *rbase;
        u32 count = 1000000;    /* 1s! */
        u32 val;

        rbase = gic_data_rdist_rd_base();

        val = readl_relaxed(rbase + GICR_WAKER);
        if (enable)
                /* Wake up this CPU redistributor */
                val &= ~GICR_WAKER_ProcessorSleep;
        else
                val |= GICR_WAKER_ProcessorSleep;
        writel_relaxed(val, rbase + GICR_WAKER);

        if (!enable) {          /* Check that GICR_WAKER is writeable */
                val = readl_relaxed(rbase + GICR_WAKER);
                if (!(val & GICR_WAKER_ProcessorSleep))
                        return; /* No PM support in this redistributor */
        }

        while (count--) {
                val = readl_relaxed(rbase + GICR_WAKER);
                if (enable ^ (bool)(val & GICR_WAKER_ChildrenAsleep))
                        break;
                cpu_relax();
                udelay(1);
        };
        if (!count)
                pr_err_ratelimited("redistributor failed to %s...\n",
                                   enable ? "wakeup" : "sleep");
}

/*
 * Routines to disable, enable, EOI and route interrupts
 */
static int gic_peek_irq(struct irq_data *d, u32 offset)
{
        u32 mask = 1 << (gic_irq(d) % 32);
        void __iomem *base;

        if (gic_irq_in_rdist(d))
                base = gic_data_rdist_sgi_base();
        else
                base = gic_data.dist_base;

        return !!(readl_relaxed(base + offset + (gic_irq(d) / 32) * 4) & mask);
}

static void gic_poke_irq(struct irq_data *d, u32 offset)
{
        u32 mask = 1 << (gic_irq(d) % 32);
        void (*rwp_wait)(void);
        void __iomem *base;

        if (gic_irq_in_rdist(d)) {
                base = gic_data_rdist_sgi_base();
                rwp_wait = gic_redist_wait_for_rwp;
        } else {
                base = gic_data.dist_base;
                rwp_wait = gic_dist_wait_for_rwp;
        }

        writel_relaxed(mask, base + offset + (gic_irq(d) / 32) * 4);
        rwp_wait();
}

static void gic_mask_irq(struct irq_data *d)
{
        gic_poke_irq(d, GICD_ICENABLER);
}

static void gic_eoimode1_mask_irq(struct irq_data *d)
{
        gic_mask_irq(d);
        /*
         * When masking a forwarded interrupt, make sure it is
         * deactivated as well.
         *
         * This ensures that an interrupt that is getting
         * disabled/masked will not get "stuck", because there is
         * noone to deactivate it (guest is being terminated).
         */
        if (irqd_is_forwarded_to_vcpu(d))
                gic_poke_irq(d, GICD_ICACTIVER);
}

static void gic_unmask_irq(struct irq_data *d)
{
        gic_poke_irq(d, GICD_ISENABLER);
}

static int gic_irq_set_irqchip_state(struct irq_data *d,
                                     enum irqchip_irq_state which, bool val)
{
        u32 reg;

        if (d->hwirq >= gic_data.irq_nr) /* PPI/SPI only */
                return -EINVAL;

        switch (which) {
        case IRQCHIP_STATE_PENDING:
                reg = val ? GICD_ISPENDR : GICD_ICPENDR;
                break;

        case IRQCHIP_STATE_ACTIVE:
                reg = val ? GICD_ISACTIVER : GICD_ICACTIVER;
                break;

        case IRQCHIP_STATE_MASKED:
                reg = val ? GICD_ICENABLER : GICD_ISENABLER;
                break;

        default:
                return -EINVAL;
        }

        gic_poke_irq(d, reg);
        return 0;
}

static int gic_irq_get_irqchip_state(struct irq_data *d,
                                     enum irqchip_irq_state which, bool *val)
{
        if (d->hwirq >= gic_data.irq_nr) /* PPI/SPI only */
                return -EINVAL;

        switch (which) {
        case IRQCHIP_STATE_PENDING:
                *val = gic_peek_irq(d, GICD_ISPENDR);
                break;

        case IRQCHIP_STATE_ACTIVE:
                *val = gic_peek_irq(d, GICD_ISACTIVER);
                break;

        case IRQCHIP_STATE_MASKED:
                *val = !gic_peek_irq(d, GICD_ISENABLER);
                break;

        default:
                return -EINVAL;
        }

        return 0;
}

static void gic_eoi_irq(struct irq_data *d)
{
        gic_write_eoir(gic_irq(d));
}

static void gic_eoimode1_eoi_irq(struct irq_data *d)
{
        /*
         * No need to deactivate an LPI, or an interrupt that
         * is is getting forwarded to a vcpu.
         */
        if (gic_irq(d) >= 8192 || irqd_is_forwarded_to_vcpu(d))
                return;
        gic_write_dir(gic_irq(d));
}

static int gic_set_type(struct irq_data *d, unsigned int type)
{
        unsigned int irq = gic_irq(d);
        void (*rwp_wait)(void);
        void __iomem *base;

        /* Interrupt configuration for SGIs can't be changed */
        if (irq < 16)
                return -EINVAL;

        /* SPIs have restrictions on the supported types */
        if (irq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
                         type != IRQ_TYPE_EDGE_RISING)
                return -EINVAL;

        if (gic_irq_in_rdist(d)) {
                base = gic_data_rdist_sgi_base();
                rwp_wait = gic_redist_wait_for_rwp;
        } else {
                base = gic_data.dist_base;
                rwp_wait = gic_dist_wait_for_rwp;
        }

        return gic_configure_irq(irq, type, base, rwp_wait);
}

static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
{
        if (vcpu)
                irqd_set_forwarded_to_vcpu(d);
        else
                irqd_clr_forwarded_to_vcpu(d);
        return 0;
}

static u64 gic_mpidr_to_affinity(unsigned long mpidr)
{
        u64 aff;

        aff = ((u64)MPIDR_AFFINITY_LEVEL(mpidr, 3) << 32 |
               MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
               MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8  |
               MPIDR_AFFINITY_LEVEL(mpidr, 0));

        return aff;
}

static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
{
        u32 irqnr;

        do {
                irqnr = gic_read_iar();

                if (likely(irqnr > 15 && irqnr < 1020) || irqnr >= 8192) {
                        int err;

                        if (static_key_true(&supports_deactivate))
                                gic_write_eoir(irqnr);

                        err = handle_domain_irq(gic_data.domain, irqnr, regs);
                        if (err) {
                                WARN_ONCE(true, "Unexpected interrupt received!\n");
                                if (static_key_true(&supports_deactivate)) {
                                        if (irqnr < 8192)
                                                gic_write_dir(irqnr);
                                } else {
                                        gic_write_eoir(irqnr);
                                }
                        }
                        continue;
                }
                if (irqnr < 16) {
                        gic_write_eoir(irqnr);
                        if (static_key_true(&supports_deactivate))
                                gic_write_dir(irqnr);
#ifdef CONFIG_SMP
                        /*
                         * Unlike GICv2, we don't need an smp_rmb() here.
                         * The control dependency from gic_read_iar to
                         * the ISB in gic_write_eoir is enough to ensure
                         * that any shared data read by handle_IPI will
                         * be read after the ACK.
                         */
                        handle_IPI(irqnr, regs);
#else
                        WARN_ONCE(true, "Unexpected SGI received!\n");
#endif
                        continue;
                }
        } while (irqnr != ICC_IAR1_EL1_SPURIOUS);
}

static void __init gic_dist_init(void)
{
        unsigned int i;
        u64 affinity;
        void __iomem *base = gic_data.dist_base;

        /* Disable the distributor */
        writel_relaxed(0, base + GICD_CTLR);
        gic_dist_wait_for_rwp();

        /*
         * Configure SPIs as non-secure Group-1. This will only matter
         * if the GIC only has a single security state. This will not
         * do the right thing if the kernel is running in secure mode,
         * but that's not the intended use case anyway.
         */
        for (i = 32; i < gic_data.irq_nr; i += 32)
                writel_relaxed(~0, base + GICD_IGROUPR + i / 8);

        gic_dist_config(base, gic_data.irq_nr, gic_dist_wait_for_rwp);

        /* Enable distributor with ARE, Group1 */
        writel_relaxed(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1,
                       base + GICD_CTLR);

        /*
         * Set all global interrupts to the boot CPU only. ARE must be
         * enabled.
         */
        affinity = gic_mpidr_to_affinity(cpu_logical_map(smp_processor_id()));
        for (i = 32; i < gic_data.irq_nr; i++)
                gic_write_irouter(affinity, base + GICD_IROUTER + i * 8);
}

static int gic_populate_rdist(void)
{
        unsigned long mpidr = cpu_logical_map(smp_processor_id());
        u64 typer;
        u32 aff;
        int i;

        /*
         * Convert affinity to a 32bit value that can be matched to
         * GICR_TYPER bits [63:32].
         */
        aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24 |
               MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
               MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
               MPIDR_AFFINITY_LEVEL(mpidr, 0));

        for (i = 0; i < gic_data.nr_redist_regions; i++) {
                void __iomem *ptr = gic_data.redist_regions[i].redist_base;
                u32 reg;

                reg = readl_relaxed(ptr + GICR_PIDR2) & GIC_PIDR2_ARCH_MASK;
                if (reg != GIC_PIDR2_ARCH_GICv3 &&
                    reg != GIC_PIDR2_ARCH_GICv4) { /* We're in trouble... */
                        pr_warn("No redistributor present @%p\n", ptr);
                        break;
                }

                do {
                        typer = gic_read_typer(ptr + GICR_TYPER);
                        if ((typer >> 32) == aff) {
                                u64 offset = ptr - gic_data.redist_regions[i].redist_base;
                                gic_data_rdist_rd_base() = ptr;
                                gic_data_rdist()->phys_base = gic_data.redist_regions[i].phys_base + offset;
                                pr_info("CPU%d: found redistributor %lx region %d:%pa\n",
                                        smp_processor_id(), mpidr, i,
                                        &gic_data_rdist()->phys_base);
                                return 0;
                        }

                        if (gic_data.redist_regions[i].single_redist)
                                break;

                        if (gic_data.redist_stride) {
                                ptr += gic_data.redist_stride;
                        } else {
                                ptr += SZ_64K * 2; /* Skip RD_base + SGI_base */
                                if (typer & GICR_TYPER_VLPIS)
                                        ptr += SZ_64K * 2; /* Skip VLPI_base + reserved page */
                        }
                } while (!(typer & GICR_TYPER_LAST));
        }

        /* We couldn't even deal with ourselves... */
        WARN(true, "CPU%d: mpidr %lx has no re-distributor!\n",
             smp_processor_id(), mpidr);
        return -ENODEV;
}

static void gic_cpu_sys_reg_init(void)
{
        /*
         * Need to check that the SRE bit has actually been set. If
         * not, it means that SRE is disabled at EL2. We're going to
         * die painfully, and there is nothing we can do about it.
         *
         * Kindly inform the luser.
         */
        if (!gic_enable_sre())
                pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n");

        /* Set priority mask register */
        gic_write_pmr(DEFAULT_PMR_VALUE);

        if (static_key_true(&supports_deactivate)) {
                /* EOI drops priority only (mode 1) */
                gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop);
        } else {
                /* EOI deactivates interrupt too (mode 0) */
                gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop_dir);
        }

        /* ... and let's hit the road... */
        gic_write_grpen1(1);
}

static int gic_dist_supports_lpis(void)
{
        return !!(readl_relaxed(gic_data.dist_base + GICD_TYPER) & GICD_TYPER_LPIS);
}

static void gic_cpu_init(void)
{
        void __iomem *rbase;

        /* Register ourselves with the rest of the world */
        if (gic_populate_rdist())
                return;

        gic_enable_redist(true);

        rbase = gic_data_rdist_sgi_base();

        /* Configure SGIs/PPIs as non-secure Group-1 */
        writel_relaxed(~0, rbase + GICR_IGROUPR0);

        gic_cpu_config(rbase, gic_redist_wait_for_rwp);

        /* Give LPIs a spin */
        if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
                its_cpu_init();

        /* initialise system registers */
        gic_cpu_sys_reg_init();
}

#ifdef CONFIG_SMP

static int gic_starting_cpu(unsigned int cpu)
{
        gic_cpu_init();
        return 0;
}

static u16 gic_compute_target_list(int *base_cpu, const struct cpumask *mask,
                                   unsigned long cluster_id)
{
        int cpu = *base_cpu;
        unsigned long mpidr = cpu_logical_map(cpu);
        u16 tlist = 0;

        while (cpu < nr_cpu_ids) {
                /*
                 * If we ever get a cluster of more than 16 CPUs, just
                 * scream and skip that CPU.
                 */
                if (WARN_ON((mpidr & 0xff) >= 16))
                        goto out;

                tlist |= 1 << (mpidr & 0xf);

                cpu = cpumask_next(cpu, mask);
                if (cpu >= nr_cpu_ids)
                        goto out;

                mpidr = cpu_logical_map(cpu);

                if (cluster_id != (mpidr & ~0xffUL)) {
                        cpu--;
                        goto out;
                }
        }
out:
        *base_cpu = cpu;
        return tlist;
}

#define MPIDR_TO_SGI_AFFINITY(cluster_id, level) \
        (MPIDR_AFFINITY_LEVEL(cluster_id, level) \
                << ICC_SGI1R_AFFINITY_## level ##_SHIFT)

static void gic_send_sgi(u64 cluster_id, u16 tlist, unsigned int irq)
{
        u64 val;

        val = (MPIDR_TO_SGI_AFFINITY(cluster_id, 3)     |
               MPIDR_TO_SGI_AFFINITY(cluster_id, 2)     |
               irq << ICC_SGI1R_SGI_ID_SHIFT            |
               MPIDR_TO_SGI_AFFINITY(cluster_id, 1)     |
               tlist << ICC_SGI1R_TARGET_LIST_SHIFT);

        pr_debug("CPU%d: ICC_SGI1R_EL1 %llx\n", smp_processor_id(), val);
        gic_write_sgi1r(val);
}

static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
{
        int cpu;

        if (WARN_ON(irq >= 16))
                return;

        /*
         * Ensure that stores to Normal memory are visible to the
         * other CPUs before issuing the IPI.
         */
        smp_wmb();

        for_each_cpu(cpu, mask) {
                unsigned long cluster_id = cpu_logical_map(cpu) & ~0xffUL;
                u16 tlist;

                tlist = gic_compute_target_list(&cpu, mask, cluster_id);
                gic_send_sgi(cluster_id, tlist, irq);
        }

        /* Force the above writes to ICC_SGI1R_EL1 to be executed */
        isb();
}

static void gic_smp_init(void)
{
        set_smp_cross_call(gic_raise_softirq);
        cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_GICV3_STARTING,
                                  "AP_IRQ_GICV3_STARTING", gic_starting_cpu,
                                  NULL);
}

static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
                            bool force)
{
        unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
        void __iomem *reg;
        int enabled;
        u64 val;

        if (gic_irq_in_rdist(d))
                return -EINVAL;

        /* If interrupt was enabled, disable it first */
        enabled = gic_peek_irq(d, GICD_ISENABLER);
        if (enabled)
                gic_mask_irq(d);

        reg = gic_dist_base(d) + GICD_IROUTER + (gic_irq(d) * 8);
        val = gic_mpidr_to_affinity(cpu_logical_map(cpu));

        gic_write_irouter(val, reg);

        /*
         * If the interrupt was enabled, enabled it again. Otherwise,
         * just wait for the distributor to have digested our changes.
         */
        if (enabled)
                gic_unmask_irq(d);
        else
                gic_dist_wait_for_rwp();

        return IRQ_SET_MASK_OK_DONE;
}
#else
#define gic_set_affinity        NULL
#define gic_smp_init()          do { } while(0)
#endif

#ifdef CONFIG_CPU_PM
/* Check whether it's single security state view */
static bool gic_dist_security_disabled(void)
{
        return readl_relaxed(gic_data.dist_base + GICD_CTLR) & GICD_CTLR_DS;
}

static int gic_cpu_pm_notifier(struct notifier_block *self,
                               unsigned long cmd, void *v)
{
        if (cmd == CPU_PM_EXIT) {
                if (gic_dist_security_disabled())
                        gic_enable_redist(true);
                gic_cpu_sys_reg_init();
        } else if (cmd == CPU_PM_ENTER && gic_dist_security_disabled()) {
                gic_write_grpen1(0);
                gic_enable_redist(false);
        }
        return NOTIFY_OK;
}

static struct notifier_block gic_cpu_pm_notifier_block = {
        .notifier_call = gic_cpu_pm_notifier,
};

static void gic_cpu_pm_init(void)
{
        cpu_pm_register_notifier(&gic_cpu_pm_notifier_block);
}

#else
static inline void gic_cpu_pm_init(void) { }
#endif /* CONFIG_CPU_PM */

static struct irq_chip gic_chip = {
        .name                   = "GICv3",
        .irq_mask               = gic_mask_irq,
        .irq_unmask             = gic_unmask_irq,
        .irq_eoi                = gic_eoi_irq,
        .irq_set_type           = gic_set_type,
        .irq_set_affinity       = gic_set_affinity,
        .irq_get_irqchip_state  = gic_irq_get_irqchip_state,
        .irq_set_irqchip_state  = gic_irq_set_irqchip_state,
        .flags                  = IRQCHIP_SET_TYPE_MASKED,
};

static struct irq_chip gic_eoimode1_chip = {
        .name                   = "GICv3",
        .irq_mask               = gic_eoimode1_mask_irq,
        .irq_unmask             = gic_unmask_irq,
        .irq_eoi                = gic_eoimode1_eoi_irq,
        .irq_set_type           = gic_set_type,
        .irq_set_affinity       = gic_set_affinity,
        .irq_get_irqchip_state  = gic_irq_get_irqchip_state,
        .irq_set_irqchip_state  = gic_irq_set_irqchip_state,
        .irq_set_vcpu_affinity  = gic_irq_set_vcpu_affinity,
        .flags                  = IRQCHIP_SET_TYPE_MASKED,
};

#define GIC_ID_NR               (1U << gic_data.rdists.id_bits)

static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
                              irq_hw_number_t hw)
{
        struct irq_chip *chip = &gic_chip;

        if (static_key_true(&supports_deactivate))
                chip = &gic_eoimode1_chip;

        /* SGIs are private to the core kernel */
        if (hw < 16)
                return -EPERM;
        /* Nothing here */
        if (hw >= gic_data.irq_nr && hw < 8192)
                return -EPERM;
        /* Off limits */
        if (hw >= GIC_ID_NR)
                return -EPERM;

        /* PPIs */
        if (hw < 32) {
                irq_set_percpu_devid(irq);
                irq_domain_set_info(d, irq, hw, chip, d->host_data,
                                    handle_percpu_devid_irq, NULL, NULL);
                irq_set_status_flags(irq, IRQ_NOAUTOEN);
        }
        /* SPIs */
        if (hw >= 32 && hw < gic_data.irq_nr) {
                irq_domain_set_info(d, irq, hw, chip, d->host_data,
                                    handle_fasteoi_irq, NULL, NULL);
                irq_set_probe(irq);
        }
        /* LPIs */
        if (hw >= 8192 && hw < GIC_ID_NR) {
                if (!gic_dist_supports_lpis())
                        return -EPERM;
                irq_domain_set_info(d, irq, hw, chip, d->host_data,
                                    handle_fasteoi_irq, NULL, NULL);
        }

        return 0;
}

static int gic_irq_domain_translate(struct irq_domain *d,
                                    struct irq_fwspec *fwspec,
                                    unsigned long *hwirq,
                                    unsigned int *type)
{
        if (is_of_node(fwspec->fwnode)) {
                if (fwspec->param_count < 3)
                        return -EINVAL;

                switch (fwspec->param[0]) {
                case 0:                 /* SPI */
                        *hwirq = fwspec->param[1] + 32;
                        break;
                case 1:                 /* PPI */
                        *hwirq = fwspec->param[1] + 16;
                        break;
                case GIC_IRQ_TYPE_LPI:  /* LPI */
                        *hwirq = fwspec->param[1];
                        break;
                default:
                        return -EINVAL;
                }

                *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
                return 0;
        }

        if (is_fwnode_irqchip(fwspec->fwnode)) {
                if(fwspec->param_count != 2)
                        return -EINVAL;

                *hwirq = fwspec->param[0];
                *type = fwspec->param[1];
                return 0;
        }

        return -EINVAL;
}

static int gic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
                                unsigned int nr_irqs, void *arg)
{
        int i, ret;
        irq_hw_number_t hwirq;
        unsigned int type = IRQ_TYPE_NONE;
        struct irq_fwspec *fwspec = arg;

        ret = gic_irq_domain_translate(domain, fwspec, &hwirq, &type);
        if (ret)
                return ret;

        for (i = 0; i < nr_irqs; i++)
                gic_irq_domain_map(domain, virq + i, hwirq + i);

        return 0;
}

static void gic_irq_domain_free(struct irq_domain *domain, unsigned int virq,
                                unsigned int nr_irqs)
{
        int i;

        for (i = 0; i < nr_irqs; i++) {
                struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
                irq_set_handler(virq + i, NULL);
                irq_domain_reset_irq_data(d);
        }
}

static int gic_irq_domain_select(struct irq_domain *d,
                                 struct irq_fwspec *fwspec,
                                 enum irq_domain_bus_token bus_token)
{
        /* Not for us */
        if (fwspec->fwnode != d->fwnode)
                return 0;

        /* If this is not DT, then we have a single domain */
        if (!is_of_node(fwspec->fwnode))
                return 1;

        /*
         * If this is a PPI and we have a 4th (non-null) parameter,
         * then we need to match the partition domain.
         */
        if (fwspec->param_count >= 4 &&
            fwspec->param[0] == 1 && fwspec->param[3] != 0)
                return d == partition_get_domain(gic_data.ppi_descs[fwspec->param[1]]);

        return d == gic_data.domain;
}

static const struct irq_domain_ops gic_irq_domain_ops = {
        .translate = gic_irq_domain_translate,
        .alloc = gic_irq_domain_alloc,
        .free = gic_irq_domain_free,
        .select = gic_irq_domain_select,
};

static int partition_domain_translate(struct irq_domain *d,
                                      struct irq_fwspec *fwspec,
                                      unsigned long *hwirq,
                                      unsigned int *type)
{
        struct device_node *np;
        int ret;

        np = of_find_node_by_phandle(fwspec->param[3]);
        if (WARN_ON(!np))
                return -EINVAL;

        ret = partition_translate_id(gic_data.ppi_descs[fwspec->param[1]],
                                     of_node_to_fwnode(np));
        if (ret < 0)
                return ret;

        *hwirq = ret;
        *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;

        return 0;
}

static const struct irq_domain_ops partition_domain_ops = {
        .translate = partition_domain_translate,
        .select = gic_irq_domain_select,
};

static void gicv3_enable_quirks(void)
{
#ifdef CONFIG_ARM64
        if (cpus_have_cap(ARM64_WORKAROUND_CAVIUM_23154))
                static_branch_enable(&is_cavium_thunderx);
#endif
}

static int __init gic_init_bases(void __iomem *dist_base,
                                 struct redist_region *rdist_regs,
                                 u32 nr_redist_regions,
                                 u64 redist_stride,
                                 struct fwnode_handle *handle)
{
        struct device_node *node;
        u32 typer;
        int gic_irqs;
        int err;

        if (!is_hyp_mode_available())
                static_key_slow_dec(&supports_deactivate);

        if (static_key_true(&supports_deactivate))
                pr_info("GIC: Using split EOI/Deactivate mode\n");

        gic_data.fwnode = handle;
        gic_data.dist_base = dist_base;
        gic_data.redist_regions = rdist_regs;
        gic_data.nr_redist_regions = nr_redist_regions;
        gic_data.redist_stride = redist_stride;

        gicv3_enable_quirks();

        /*
         * Find out how many interrupts are supported.
         * The GIC only supports up to 1020 interrupt sources (SGI+PPI+SPI)
         */
        typer = readl_relaxed(gic_data.dist_base + GICD_TYPER);
        gic_data.rdists.id_bits = GICD_TYPER_ID_BITS(typer);
        gic_irqs = GICD_TYPER_IRQS(typer);
        if (gic_irqs > 1020)
                gic_irqs = 1020;
        gic_data.irq_nr = gic_irqs;

        gic_data.domain = irq_domain_create_tree(handle, &gic_irq_domain_ops,
                                                 &gic_data);
        gic_data.rdists.rdist = alloc_percpu(typeof(*gic_data.rdists.rdist));

        if (WARN_ON(!gic_data.domain) || WARN_ON(!gic_data.rdists.rdist)) {
                err = -ENOMEM;
                goto out_free;
        }

        set_handle_irq(gic_handle_irq);

        node = to_of_node(handle);
        if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis() &&
            node) /* Temp hack to prevent ITS init for ACPI */
                its_init(node, &gic_data.rdists, gic_data.domain);

        gic_smp_init();
        gic_dist_init();
        gic_cpu_init();
        gic_cpu_pm_init();

        return 0;

out_free:
        if (gic_data.domain)
                irq_domain_remove(gic_data.domain);
        free_percpu(gic_data.rdists.rdist);
        return err;
}

static int __init gic_validate_dist_version(void __iomem *dist_base)
{
        u32 reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;

        if (reg != GIC_PIDR2_ARCH_GICv3 && reg != GIC_PIDR2_ARCH_GICv4)
                return -ENODEV;

        return 0;
}

static int get_cpu_number(struct device_node *dn)
{
        const __be32 *cell;
        u64 hwid;
        int i;

        cell = of_get_property(dn, "reg", NULL);
        if (!cell)
                return -1;

        hwid = of_read_number(cell, of_n_addr_cells(dn));

        /*
         * Non affinity bits must be set to 0 in the DT
         */
        if (hwid & ~MPIDR_HWID_BITMASK)
                return -1;

        for (i = 0; i < num_possible_cpus(); i++)
                if (cpu_logical_map(i) == hwid)
                        return i;

        return -1;
}

/* Create all possible partitions at boot time */
static void __init gic_populate_ppi_partitions(struct device_node *gic_node)
{
        struct device_node *parts_node, *child_part;
        int part_idx = 0, i;
        int nr_parts;
        struct partition_affinity *parts;

        parts_node = of_find_node_by_name(gic_node, "ppi-partitions");
        if (!parts_node)
                return;

        nr_parts = of_get_child_count(parts_node);

        if (!nr_parts)
                return;

        parts = kzalloc(sizeof(*parts) * nr_parts, GFP_KERNEL);
        if (WARN_ON(!parts))
                return;

        for_each_child_of_node(parts_node, child_part) {
                struct partition_affinity *part;
                int n;

                part = &parts[part_idx];

                part->partition_id = of_node_to_fwnode(child_part);

                pr_info("GIC: PPI partition %s[%d] { ",
                        child_part->name, part_idx);

                n = of_property_count_elems_of_size(child_part, "affinity",
                                                    sizeof(u32));
                WARN_ON(n <= 0);

                for (i = 0; i < n; i++) {
                        int err, cpu;
                        u32 cpu_phandle;
                        struct device_node *cpu_node;

                        err = of_property_read_u32_index(child_part, "affinity",
                                                         i, &cpu_phandle);
                        if (WARN_ON(err))
                                continue;

                        cpu_node = of_find_node_by_phandle(cpu_phandle);
                        if (WARN_ON(!cpu_node))
                                continue;

                        cpu = get_cpu_number(cpu_node);
                        if (WARN_ON(cpu == -1))
                                continue;

                        pr_cont("%s[%d] ", cpu_node->full_name, cpu);

                        cpumask_set_cpu(cpu, &part->mask);
                }

                pr_cont("}\n");
                part_idx++;
        }

        for (i = 0; i < 16; i++) {
                unsigned int irq;
                struct partition_desc *desc;
                struct irq_fwspec ppi_fwspec = {
                        .fwnode         = gic_data.fwnode,
                        .param_count    = 3,
                        .param          = {
                                [0]     = 1,
                                [1]     = i,
                                [2]     = IRQ_TYPE_NONE,
                        },
                };

                irq = irq_create_fwspec_mapping(&ppi_fwspec);
                if (WARN_ON(!irq))
                        continue;
                desc = partition_create_desc(gic_data.fwnode, parts, nr_parts,
                                             irq, &partition_domain_ops);
                if (WARN_ON(!desc))
                        continue;

                gic_data.ppi_descs[i] = desc;
        }
}

static void __init gic_of_setup_kvm_info(struct device_node *node)
{
        int ret;
        struct resource r;
        u32 gicv_idx;

        gic_v3_kvm_info.type = GIC_V3;

        gic_v3_kvm_info.maint_irq = irq_of_parse_and_map(node, 0);
        if (!gic_v3_kvm_info.maint_irq)
                return;

        if (of_property_read_u32(node, "#redistributor-regions",
                                 &gicv_idx))
                gicv_idx = 1;

        gicv_idx += 3;  /* Also skip GICD, GICC, GICH */
        ret = of_address_to_resource(node, gicv_idx, &r);
        if (!ret)
                gic_v3_kvm_info.vcpu = r;

        gic_set_kvm_info(&gic_v3_kvm_info);
}

static int __init gic_of_init(struct device_node *node, struct device_node *parent)
{
        void __iomem *dist_base;
        struct redist_region *rdist_regs;
        u64 redist_stride;
        u32 nr_redist_regions;
        int err, i;

        dist_base = of_iomap(node, 0);
        if (!dist_base) {
                pr_err("%s: unable to map gic dist registers\n",
                        node->full_name);
                return -ENXIO;
        }

        err = gic_validate_dist_version(dist_base);
        if (err) {
                pr_err("%s: no distributor detected, giving up\n",
                        node->full_name);
                goto out_unmap_dist;
        }

        if (of_property_read_u32(node, "#redistributor-regions", &nr_redist_regions))
                nr_redist_regions = 1;

        rdist_regs = kzalloc(sizeof(*rdist_regs) * nr_redist_regions, GFP_KERNEL);
        if (!rdist_regs) {
                err = -ENOMEM;
                goto out_unmap_dist;
        }

        for (i = 0; i < nr_redist_regions; i++) {
                struct resource res;
                int ret;

                ret = of_address_to_resource(node, 1 + i, &res);
                rdist_regs[i].redist_base = of_iomap(node, 1 + i);
                if (ret || !rdist_regs[i].redist_base) {
                        pr_err("%s: couldn't map region %d\n",
                               node->full_name, i);
                        err = -ENODEV;
                        goto out_unmap_rdist;
                }
                rdist_regs[i].phys_base = res.start;
        }

        if (of_property_read_u64(node, "redistributor-stride", &redist_stride))
                redist_stride = 0;

        err = gic_init_bases(dist_base, rdist_regs, nr_redist_regions,
                             redist_stride, &node->fwnode);
        if (err)
                goto out_unmap_rdist;

        gic_populate_ppi_partitions(node);
        gic_of_setup_kvm_info(node);
        return 0;

out_unmap_rdist:
        for (i = 0; i < nr_redist_regions; i++)
                if (rdist_regs[i].redist_base)
                        iounmap(rdist_regs[i].redist_base);
        kfree(rdist_regs);
out_unmap_dist:
        iounmap(dist_base);
        return err;
}

IRQCHIP_DECLARE(gic_v3, "arm,gic-v3", gic_of_init);

#ifdef CONFIG_ACPI
static struct
{
        void __iomem *dist_base;
        struct redist_region *redist_regs;
        u32 nr_redist_regions;
        bool single_redist;
        u32 maint_irq;
        int maint_irq_mode;
        phys_addr_t vcpu_base;
} acpi_data __initdata;

static void __init
gic_acpi_register_redist(phys_addr_t phys_base, void __iomem *redist_base)
{
        static int count = 0;

        acpi_data.redist_regs[count].phys_base = phys_base;
        acpi_data.redist_regs[count].redist_base = redist_base;
        acpi_data.redist_regs[count].single_redist = acpi_data.single_redist;
        count++;
}

static int __init
gic_acpi_parse_madt_redist(struct acpi_subtable_header *header,
                           const unsigned long end)
{
        struct acpi_madt_generic_redistributor *redist =
                        (struct acpi_madt_generic_redistributor *)header;
        void __iomem *redist_base;

        redist_base = ioremap(redist->base_address, redist->length);
        if (!redist_base) {
                pr_err("Couldn't map GICR region @%llx\n", redist->base_address);
                return -ENOMEM;
        }

        gic_acpi_register_redist(redist->base_address, redist_base);
        return 0;
}

static int __init
gic_acpi_parse_madt_gicc(struct acpi_subtable_header *header,
                         const unsigned long end)
{
        struct acpi_madt_generic_interrupt *gicc =
                                (struct acpi_madt_generic_interrupt *)header;
        u32 reg = readl_relaxed(acpi_data.dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
        u32 size = reg == GIC_PIDR2_ARCH_GICv4 ? SZ_64K * 4 : SZ_64K * 2;
        void __iomem *redist_base;

        redist_base = ioremap(gicc->gicr_base_address, size);
        if (!redist_base)
                return -ENOMEM;

        gic_acpi_register_redist(gicc->gicr_base_address, redist_base);
        return 0;
}

static int __init gic_acpi_collect_gicr_base(void)
{
        acpi_tbl_entry_handler redist_parser;
        enum acpi_madt_type type;

        if (acpi_data.single_redist) {
                type = ACPI_MADT_TYPE_GENERIC_INTERRUPT;
                redist_parser = gic_acpi_parse_madt_gicc;
        } else {
                type = ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR;
                redist_parser = gic_acpi_parse_madt_redist;
        }

        /* Collect redistributor base addresses in GICR entries */
        if (acpi_table_parse_madt(type, redist_parser, 0) > 0)
                return 0;

        pr_info("No valid GICR entries exist\n");
        return -ENODEV;
}

static int __init gic_acpi_match_gicr(struct acpi_subtable_header *header,
                                  const unsigned long end)
{
        /* Subtable presence means that redist exists, that's it */
        return 0;
}

static int __init gic_acpi_match_gicc(struct acpi_subtable_header *header,
                                      const unsigned long end)
{
        struct acpi_madt_generic_interrupt *gicc =
                                (struct acpi_madt_generic_interrupt *)header;

        /*
         * If GICC is enabled and has valid gicr base address, then it means
         * GICR base is presented via GICC
         */
        if ((gicc->flags & ACPI_MADT_ENABLED) && gicc->gicr_base_address)
                return 0;

        return -ENODEV;
}

static int __init gic_acpi_count_gicr_regions(void)
{
        int count;

        /*
         * Count how many redistributor regions we have. It is not allowed
         * to mix redistributor description, GICR and GICC subtables have to be
         * mutually exclusive.
         */
        count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR,
                                      gic_acpi_match_gicr, 0);
        if (count > 0) {
                acpi_data.single_redist = false;
                return count;
        }

        count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
                                      gic_acpi_match_gicc, 0);
        if (count > 0)
                acpi_data.single_redist = true;

        return count;
}

static bool __init acpi_validate_gic_table(struct acpi_subtable_header *header,
                                           struct acpi_probe_entry *ape)
{
        struct acpi_madt_generic_distributor *dist;
        int count;

        dist = (struct acpi_madt_generic_distributor *)header;
        if (dist->version != ape->driver_data)
                return false;

        /* We need to do that exercise anyway, the sooner the better */
        count = gic_acpi_count_gicr_regions();
        if (count <= 0)
                return false;

        acpi_data.nr_redist_regions = count;
        return true;
}

static int __init gic_acpi_parse_virt_madt_gicc(struct acpi_subtable_header *header,
                                                const unsigned long end)
{
        struct acpi_madt_generic_interrupt *gicc =
                (struct acpi_madt_generic_interrupt *)header;
        int maint_irq_mode;
        static int first_madt = true;

        /* Skip unusable CPUs */
        if (!(gicc->flags & ACPI_MADT_ENABLED))
                return 0;

        maint_irq_mode = (gicc->flags & ACPI_MADT_VGIC_IRQ_MODE) ?
                ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE;

        if (first_madt) {
                first_madt = false;

                acpi_data.maint_irq = gicc->vgic_interrupt;
                acpi_data.maint_irq_mode = maint_irq_mode;
                acpi_data.vcpu_base = gicc->gicv_base_address;

                return 0;
        }

        /*
         * The maintenance interrupt and GICV should be the same for every CPU
         */
        if ((acpi_data.maint_irq != gicc->vgic_interrupt) ||
            (acpi_data.maint_irq_mode != maint_irq_mode) ||
            (acpi_data.vcpu_base != gicc->gicv_base_address))
                return -EINVAL;

        return 0;
}

static bool __init gic_acpi_collect_virt_info(void)
{
        int count;

        count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
                                      gic_acpi_parse_virt_madt_gicc, 0);

        return (count > 0);
}

#define ACPI_GICV3_DIST_MEM_SIZE (SZ_64K)
#define ACPI_GICV2_VCTRL_MEM_SIZE       (SZ_4K)
#define ACPI_GICV2_VCPU_MEM_SIZE        (SZ_8K)

static void __init gic_acpi_setup_kvm_info(void)
{
        int irq;

        if (!gic_acpi_collect_virt_info()) {
                pr_warn("Unable to get hardware information used for virtualization\n");
                return;
        }

        gic_v3_kvm_info.type = GIC_V3;

        irq = acpi_register_gsi(NULL, acpi_data.maint_irq,
                                acpi_data.maint_irq_mode,
                                ACPI_ACTIVE_HIGH);
        if (irq <= 0)
                return;

        gic_v3_kvm_info.maint_irq = irq;

        if (acpi_data.vcpu_base) {
                struct resource *vcpu = &gic_v3_kvm_info.vcpu;

                vcpu->flags = IORESOURCE_MEM;
                vcpu->start = acpi_data.vcpu_base;
                vcpu->end = vcpu->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
        }

        gic_set_kvm_info(&gic_v3_kvm_info);
}

static int __init
gic_acpi_init(struct acpi_subtable_header *header, const unsigned long end)
{
        struct acpi_madt_generic_distributor *dist;
        struct fwnode_handle *domain_handle;
        size_t size;
        int i, err;

        /* Get distributor base address */
        dist = (struct acpi_madt_generic_distributor *)header;
        acpi_data.dist_base = ioremap(dist->base_address,
                                      ACPI_GICV3_DIST_MEM_SIZE);
        if (!acpi_data.dist_base) {
                pr_err("Unable to map GICD registers\n");
                return -ENOMEM;
        }

        err = gic_validate_dist_version(acpi_data.dist_base);
        if (err) {
                pr_err("No distributor detected at @%p, giving up",
                       acpi_data.dist_base);
                goto out_dist_unmap;
        }

        size = sizeof(*acpi_data.redist_regs) * acpi_data.nr_redist_regions;
        acpi_data.redist_regs = kzalloc(size, GFP_KERNEL);
        if (!acpi_data.redist_regs) {
                err = -ENOMEM;
                goto out_dist_unmap;
        }

        err = gic_acpi_collect_gicr_base();
        if (err)
                goto out_redist_unmap;

        domain_handle = irq_domain_alloc_fwnode(acpi_data.dist_base);
        if (!domain_handle) {
                err = -ENOMEM;
                goto out_redist_unmap;
        }

        err = gic_init_bases(acpi_data.dist_base, acpi_data.redist_regs,
                             acpi_data.nr_redist_regions, 0, domain_handle);
        if (err)
                goto out_fwhandle_free;

        acpi_set_irq_model(ACPI_IRQ_MODEL_GIC, domain_handle);
        gic_acpi_setup_kvm_info();

        return 0;

out_fwhandle_free:
        irq_domain_free_fwnode(domain_handle);
out_redist_unmap:
        for (i = 0; i < acpi_data.nr_redist_regions; i++)
                if (acpi_data.redist_regs[i].redist_base)
                        iounmap(acpi_data.redist_regs[i].redist_base);
        kfree(acpi_data.redist_regs);
out_dist_unmap:
        iounmap(acpi_data.dist_base);
        return err;
}
IRQCHIP_ACPI_DECLARE(gic_v3, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
                     acpi_validate_gic_table, ACPI_MADT_GIC_VERSION_V3,
                     gic_acpi_init);
IRQCHIP_ACPI_DECLARE(gic_v4, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
                     acpi_validate_gic_table, ACPI_MADT_GIC_VERSION_V4,
                     gic_acpi_init);
IRQCHIP_ACPI_DECLARE(gic_v3_or_v4, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
                     acpi_validate_gic_table, ACPI_MADT_GIC_VERSION_NONE,
                     gic_acpi_init);
#endif