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irq-gic-v3.c
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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2013-2017 ARM Limited, All Rights Reserved.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
#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/refcount.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"
#define GICD_INT_NMI_PRI (GICD_INT_DEF_PRI & ~0x80)
#define FLAGS_WORKAROUND_GICR_WAKER_MSM8996 (1ULL << 0)
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;
u64 flags;
bool has_rss;
unsigned int ppi_nr;
struct partition_desc **ppi_descs;
};
static struct gic_chip_data gic_data __read_mostly;
static DEFINE_STATIC_KEY_TRUE(supports_deactivate_key);
#define GIC_ID_NR (1U << GICD_TYPER_ID_BITS(gic_data.rdists.gicd_typer))
#define GIC_LINE_NR min(GICD_TYPER_SPIS(gic_data.rdists.gicd_typer), 1020U)
#define GIC_ESPI_NR GICD_TYPER_ESPIS(gic_data.rdists.gicd_typer)
/*
* The behaviours of RPR and PMR registers differ depending on the value of
* SCR_EL3.FIQ, and the behaviour of non-secure priority registers of the
* distributor and redistributors depends on whether security is enabled in the
* GIC.
*
* When security is enabled, non-secure priority values from the (re)distributor
* are presented to the GIC CPUIF as follow:
* (GIC_(R)DIST_PRI[irq] >> 1) | 0x80;
*
* If SCR_EL3.FIQ == 1, the values writen to/read from PMR and RPR at non-secure
* EL1 are subject to a similar operation thus matching the priorities presented
* from the (re)distributor when security is enabled.
*
* see GICv3/GICv4 Architecture Specification (IHI0069D):
* - section 4.8.1 Non-secure accesses to register fields for Secure interrupt
* priorities.
* - Figure 4-7 Secure read of the priority field for a Non-secure Group 1
* interrupt.
*
* For now, we only support pseudo-NMIs if we have non-secure view of
* priorities.
*/
static DEFINE_STATIC_KEY_FALSE(supports_pseudo_nmis);
/* ppi_nmi_refs[n] == number of cpus having ppi[n + 16] set as NMI */
static refcount_t *ppi_nmi_refs;
static struct gic_kvm_info gic_v3_kvm_info;
static DEFINE_PER_CPU(bool, has_rss);
#define MPIDR_RS(mpidr) (((mpidr) & 0xF0UL) >> 4)
#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
enum gic_intid_range {
PPI_RANGE,
SPI_RANGE,
EPPI_RANGE,
ESPI_RANGE,
LPI_RANGE,
__INVALID_RANGE__
};
static enum gic_intid_range __get_intid_range(irq_hw_number_t hwirq)
{
switch (hwirq) {
case 16 ... 31:
return PPI_RANGE;
case 32 ... 1019:
return SPI_RANGE;
case EPPI_BASE_INTID ... (EPPI_BASE_INTID + 63):
return EPPI_RANGE;
case ESPI_BASE_INTID ... (ESPI_BASE_INTID + 1023):
return ESPI_RANGE;
case 8192 ... GENMASK(23, 0):
return LPI_RANGE;
default:
return __INVALID_RANGE__;
}
}
static enum gic_intid_range get_intid_range(struct irq_data *d)
{
return __get_intid_range(d->hwirq);
}
static inline unsigned int gic_irq(struct irq_data *d)
{
return d->hwirq;
}
static inline int gic_irq_in_rdist(struct irq_data *d)
{
enum gic_intid_range range = get_intid_range(d);
return range == PPI_RANGE || range == EPPI_RANGE;
}
static inline void __iomem *gic_dist_base(struct irq_data *d)
{
switch (get_intid_range(d)) {
case PPI_RANGE:
case EPPI_RANGE:
/* SGI+PPI -> SGI_base for this CPU */
return gic_data_rdist_sgi_base();
case SPI_RANGE:
case ESPI_RANGE:
/* SPI -> dist_base */
return gic_data.dist_base;
default:
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 u64 __maybe_unused gic_read_iar(void)
{
if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_23154))
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;
if (gic_data.flags & FLAGS_WORKAROUND_GICR_WAKER_MSM8996)
return;
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 u32 convert_offset_index(struct irq_data *d, u32 offset, u32 *index)
{
switch (get_intid_range(d)) {
case PPI_RANGE:
case SPI_RANGE:
*index = d->hwirq;
return offset;
case EPPI_RANGE:
/*
* Contrary to the ESPI range, the EPPI range is contiguous
* to the PPI range in the registers, so let's adjust the
* displacement accordingly. Consistency is overrated.
*/
*index = d->hwirq - EPPI_BASE_INTID + 32;
return offset;
case ESPI_RANGE:
*index = d->hwirq - ESPI_BASE_INTID;
switch (offset) {
case GICD_ISENABLER:
return GICD_ISENABLERnE;
case GICD_ICENABLER:
return GICD_ICENABLERnE;
case GICD_ISPENDR:
return GICD_ISPENDRnE;
case GICD_ICPENDR:
return GICD_ICPENDRnE;
case GICD_ISACTIVER:
return GICD_ISACTIVERnE;
case GICD_ICACTIVER:
return GICD_ICACTIVERnE;
case GICD_IPRIORITYR:
return GICD_IPRIORITYRnE;
case GICD_ICFGR:
return GICD_ICFGRnE;
case GICD_IROUTER:
return GICD_IROUTERnE;
default:
break;
}
break;
default:
break;
}
WARN_ON(1);
*index = d->hwirq;
return offset;
}
static int gic_peek_irq(struct irq_data *d, u32 offset)
{
void __iomem *base;
u32 index, mask;
offset = convert_offset_index(d, offset, &index);
mask = 1 << (index % 32);
if (gic_irq_in_rdist(d))
base = gic_data_rdist_sgi_base();
else
base = gic_data.dist_base;
return !!(readl_relaxed(base + offset + (index / 32) * 4) & mask);
}
static void gic_poke_irq(struct irq_data *d, u32 offset)
{
void (*rwp_wait)(void);
void __iomem *base;
u32 index, mask;
offset = convert_offset_index(d, offset, &index);
mask = 1 << (index % 32);
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 + (index / 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 inline bool gic_supports_nmi(void)
{
return IS_ENABLED(CONFIG_ARM64_PSEUDO_NMI) &&
static_branch_likely(&supports_pseudo_nmis);
}
static int gic_irq_set_irqchip_state(struct irq_data *d,
enum irqchip_irq_state which, bool val)
{
u32 reg;
if (d->hwirq >= 8192) /* 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 >= 8192) /* 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_irq_set_prio(struct irq_data *d, u8 prio)
{
void __iomem *base = gic_dist_base(d);
u32 offset, index;
offset = convert_offset_index(d, GICD_IPRIORITYR, &index);
writeb_relaxed(prio, base + offset + index);
}
static u32 gic_get_ppi_index(struct irq_data *d)
{
switch (get_intid_range(d)) {
case PPI_RANGE:
return d->hwirq - 16;
case EPPI_RANGE:
return d->hwirq - EPPI_BASE_INTID + 16;
default:
unreachable();
}
}
static int gic_irq_nmi_setup(struct irq_data *d)
{
struct irq_desc *desc = irq_to_desc(d->irq);
if (!gic_supports_nmi())
return -EINVAL;
if (gic_peek_irq(d, GICD_ISENABLER)) {
pr_err("Cannot set NMI property of enabled IRQ %u\n", d->irq);
return -EINVAL;
}
/*
* A secondary irq_chip should be in charge of LPI request,
* it should not be possible to get there
*/
if (WARN_ON(gic_irq(d) >= 8192))
return -EINVAL;
/* desc lock should already be held */
if (gic_irq_in_rdist(d)) {
u32 idx = gic_get_ppi_index(d);
/* Setting up PPI as NMI, only switch handler for first NMI */
if (!refcount_inc_not_zero(&ppi_nmi_refs[idx])) {
refcount_set(&ppi_nmi_refs[idx], 1);
desc->handle_irq = handle_percpu_devid_fasteoi_nmi;
}
} else {
desc->handle_irq = handle_fasteoi_nmi;
}
gic_irq_set_prio(d, GICD_INT_NMI_PRI);
return 0;
}
static void gic_irq_nmi_teardown(struct irq_data *d)
{
struct irq_desc *desc = irq_to_desc(d->irq);
if (WARN_ON(!gic_supports_nmi()))
return;
if (gic_peek_irq(d, GICD_ISENABLER)) {
pr_err("Cannot set NMI property of enabled IRQ %u\n", d->irq);
return;
}
/*
* A secondary irq_chip should be in charge of LPI request,
* it should not be possible to get there
*/
if (WARN_ON(gic_irq(d) >= 8192))
return;
/* desc lock should already be held */
if (gic_irq_in_rdist(d)) {
u32 idx = gic_get_ppi_index(d);
/* Tearing down NMI, only switch handler for last NMI */
if (refcount_dec_and_test(&ppi_nmi_refs[idx]))
desc->handle_irq = handle_percpu_devid_irq;
} else {
desc->handle_irq = handle_fasteoi_irq;
}
gic_irq_set_prio(d, GICD_INT_DEF_PRI);
}
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)
{
enum gic_intid_range range;
unsigned int irq = gic_irq(d);
void (*rwp_wait)(void);
void __iomem *base;
u32 offset, index;
int ret;
/* Interrupt configuration for SGIs can't be changed */
if (irq < 16)
return -EINVAL;
range = get_intid_range(d);
/* SPIs have restrictions on the supported types */
if ((range == SPI_RANGE || range == ESPI_RANGE) &&
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;
}
offset = convert_offset_index(d, GICD_ICFGR, &index);
ret = gic_configure_irq(index, type, base + offset, rwp_wait);
if (ret && (range == PPI_RANGE || range == EPPI_RANGE)) {
/* Misconfigured PPIs are usually not fatal */
pr_warn("GIC: PPI INTID%d is secure or misconfigured\n", irq);
ret = 0;
}
return ret;
}
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 void gic_deactivate_unhandled(u32 irqnr)
{
if (static_branch_likely(&supports_deactivate_key)) {
if (irqnr < 8192)
gic_write_dir(irqnr);
} else {
gic_write_eoir(irqnr);
}
}
static inline void gic_handle_nmi(u32 irqnr, struct pt_regs *regs)
{
bool irqs_enabled = interrupts_enabled(regs);
int err;
if (irqs_enabled)
nmi_enter();
if (static_branch_likely(&supports_deactivate_key))
gic_write_eoir(irqnr);
/*
* Leave the PSR.I bit set to prevent other NMIs to be
* received while handling this one.
* PSR.I will be restored when we ERET to the
* interrupted context.
*/
err = handle_domain_nmi(gic_data.domain, irqnr, regs);
if (err)
gic_deactivate_unhandled(irqnr);
if (irqs_enabled)
nmi_exit();
}
static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
{
u32 irqnr;
irqnr = gic_read_iar();
if (gic_supports_nmi() &&
unlikely(gic_read_rpr() == GICD_INT_NMI_PRI)) {
gic_handle_nmi(irqnr, regs);
return;
}
if (gic_prio_masking_enabled()) {
gic_pmr_mask_irqs();
gic_arch_enable_irqs();
}
/* Check for special IDs first */
if ((irqnr >= 1020 && irqnr <= 1023))
return;
/* Treat anything but SGIs in a uniform way */
if (likely(irqnr > 15)) {
int err;
if (static_branch_likely(&supports_deactivate_key))
gic_write_eoir(irqnr);
else
isb();
err = handle_domain_irq(gic_data.domain, irqnr, regs);
if (err) {
WARN_ONCE(true, "Unexpected interrupt received!\n");
gic_deactivate_unhandled(irqnr);
}
return;
}
if (irqnr < 16) {
gic_write_eoir(irqnr);
if (static_branch_likely(&supports_deactivate_key))
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
}
}
static u32 gic_get_pribits(void)
{
u32 pribits;
pribits = gic_read_ctlr();
pribits &= ICC_CTLR_EL1_PRI_BITS_MASK;
pribits >>= ICC_CTLR_EL1_PRI_BITS_SHIFT;
pribits++;
return pribits;
}
static bool gic_has_group0(void)
{
u32 val;
u32 old_pmr;
old_pmr = gic_read_pmr();
/*
* Let's find out if Group0 is under control of EL3 or not by
* setting the highest possible, non-zero priority in PMR.
*
* If SCR_EL3.FIQ is set, the priority gets shifted down in
* order for the CPU interface to set bit 7, and keep the
* actual priority in the non-secure range. In the process, it
* looses the least significant bit and the actual priority
* becomes 0x80. Reading it back returns 0, indicating that
* we're don't have access to Group0.
*/
gic_write_pmr(BIT(8 - gic_get_pribits()));
val = gic_read_pmr();
gic_write_pmr(old_pmr);
return val != 0;
}
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_LINE_NR; i += 32)
writel_relaxed(~0, base + GICD_IGROUPR + i / 8);
/* Extended SPI range, not handled by the GICv2/GICv3 common code */
for (i = 0; i < GIC_ESPI_NR; i += 32) {
writel_relaxed(~0U, base + GICD_ICENABLERnE + i / 8);
writel_relaxed(~0U, base + GICD_ICACTIVERnE + i / 8);
}
for (i = 0; i < GIC_ESPI_NR; i += 32)
writel_relaxed(~0U, base + GICD_IGROUPRnE + i / 8);
for (i = 0; i < GIC_ESPI_NR; i += 16)
writel_relaxed(0, base + GICD_ICFGRnE + i / 4);
for (i = 0; i < GIC_ESPI_NR; i += 4)
writel_relaxed(GICD_INT_DEF_PRI_X4, base + GICD_IPRIORITYRnE + i);
/* Now do the common stuff, and wait for the distributor to drain */
gic_dist_config(base, GIC_LINE_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_LINE_NR; i++)
gic_write_irouter(affinity, base + GICD_IROUTER + i * 8);
for (i = 0; i < GIC_ESPI_NR; i++)
gic_write_irouter(affinity, base + GICD_IROUTERnE + i * 8);
}
static int gic_iterate_rdists(int (*fn)(struct redist_region *, void __iomem *))
{
int ret = -ENODEV;
int i;
for (i = 0; i < gic_data.nr_redist_regions; i++) {
void __iomem *ptr = gic_data.redist_regions[i].redist_base;
u64 typer;
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);
ret = fn(gic_data.redist_regions + i, ptr);
if (!ret)
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));
}
return ret ? -ENODEV : 0;
}
static int __gic_populate_rdist(struct redist_region *region, void __iomem *ptr)
{
unsigned long mpidr = cpu_logical_map(smp_processor_id());
u64 typer;
u32 aff;
/*
* 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));
typer = gic_read_typer(ptr + GICR_TYPER);
if ((typer >> 32) == aff) {
u64 offset = ptr - region->redist_base;
gic_data_rdist_rd_base() = ptr;
gic_data_rdist()->phys_base = region->phys_base + offset;
pr_info("CPU%d: found redistributor %lx region %d:%pa\n",
smp_processor_id(), mpidr,
(int)(region - gic_data.redist_regions),
&gic_data_rdist()->phys_base);
return 0;
}
/* Try next one */
return 1;
}
static int gic_populate_rdist(void)
{
if (gic_iterate_rdists(__gic_populate_rdist) == 0)
return 0;
/* We couldn't even deal with ourselves... */
WARN(true, "CPU%d: mpidr %lx has no re-distributor!\n",
smp_processor_id(),
(unsigned long)cpu_logical_map(smp_processor_id()));
return -ENODEV;
}
static int __gic_update_rdist_properties(struct redist_region *region,
void __iomem *ptr)
{
u64 typer = gic_read_typer(ptr + GICR_TYPER);
gic_data.rdists.has_vlpis &= !!(typer & GICR_TYPER_VLPIS);
gic_data.rdists.has_direct_lpi &= !!(typer & GICR_TYPER_DirectLPIS);
gic_data.ppi_nr = min(GICR_TYPER_NR_PPIS(typer), gic_data.ppi_nr);
return 1;
}
static void gic_update_rdist_properties(void)
{
gic_data.ppi_nr = UINT_MAX;
gic_iterate_rdists(__gic_update_rdist_properties);
if (WARN_ON(gic_data.ppi_nr == UINT_MAX))
gic_data.ppi_nr = 0;
pr_info("%d PPIs implemented\n", gic_data.ppi_nr);
pr_info("%sVLPI support, %sdirect LPI support\n",
!gic_data.rdists.has_vlpis ? "no " : "",
!gic_data.rdists.has_direct_lpi ? "no " : "");
}
/* Check whether it's single security state view */
static inline bool gic_dist_security_disabled(void)
{
return readl_relaxed(gic_data.dist_base + GICD_CTLR) & GICD_CTLR_DS;
}
static void gic_cpu_sys_reg_init(void)
{
int i, cpu = smp_processor_id();
u64 mpidr = cpu_logical_map(cpu);
u64 need_rss = MPIDR_RS(mpidr);
bool group0;
u32 pribits;
/*
* 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");
pribits = gic_get_pribits();
group0 = gic_has_group0();
/* Set priority mask register */
if (!gic_prio_masking_enabled()) {
write_gicreg(DEFAULT_PMR_VALUE, ICC_PMR_EL1);
} else {
/*
* Mismatch configuration with boot CPU, the system is likely
* to die as interrupt masking will not work properly on all
* CPUs
*/
WARN_ON(gic_supports_nmi() && group0 &&
!gic_dist_security_disabled());
}
/*
* Some firmwares hand over to the kernel with the BPR changed from
* its reset value (and with a value large enough to prevent
* any pre-emptive interrupts from working at all). Writing a zero
* to BPR restores is reset value.
*/
gic_write_bpr1(0);
if (static_branch_likely(&supports_deactivate_key)) {
/* 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);
}
/* Always whack Group0 before Group1 */
if (group0) {
switch(pribits) {
case 8:
case 7:
write_gicreg(0, ICC_AP0R3_EL1);
write_gicreg(0, ICC_AP0R2_EL1);
/* Fall through */
case 6:
write_gicreg(0, ICC_AP0R1_EL1);
/* Fall through */
case 5:
case 4:
write_gicreg(0, ICC_AP0R0_EL1);
}
isb();
}
switch(pribits) {
case 8:
case 7:
write_gicreg(0, ICC_AP1R3_EL1);
write_gicreg(0, ICC_AP1R2_EL1);
/* Fall through */
case 6:
write_gicreg(0, ICC_AP1R1_EL1);
/* Fall through */
case 5:
case 4:
write_gicreg(0, ICC_AP1R0_EL1);
}
isb();
/* ... and let's hit the road... */
gic_write_grpen1(1);
/* Keep the RSS capability status in per_cpu variable */
per_cpu(has_rss, cpu) = !!(gic_read_ctlr() & ICC_CTLR_EL1_RSS);
/* Check all the CPUs have capable of sending SGIs to other CPUs */
for_each_online_cpu(i) {
bool have_rss = per_cpu(has_rss, i) && per_cpu(has_rss, cpu);
need_rss |= MPIDR_RS(cpu_logical_map(i));
if (need_rss && (!have_rss))
pr_crit("CPU%d (%lx) can't SGI CPU%d (%lx), no RSS\n",
cpu, (unsigned long)mpidr,
i, (unsigned long)cpu_logical_map(i));
}
/**
* GIC spec says, when ICC_CTLR_EL1.RSS==1 and GICD_TYPER.RSS==0,
* writing ICC_ASGI1R_EL1 register with RS != 0 is a CONSTRAINED
* UNPREDICTABLE choice of :
* - The write is ignored.
* - The RS field is treated as 0.
*/
if (need_rss && (!gic_data.has_rss))
pr_crit_once("RSS is required but GICD doesn't support it\n");
}
static bool gicv3_nolpi;
static int __init gicv3_nolpi_cfg(char *buf)
{
return strtobool(buf, &gicv3_nolpi);
}
early_param("irqchip.gicv3_nolpi", gicv3_nolpi_cfg);
static int gic_dist_supports_lpis(void)
{