android_kernel_oneplus_msm8998/drivers/irqchip/irq-gic-v3.c

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/*
* 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/>.
*/
#include <linux/cpu.h>
#include <linux/cpu_pm.h>
#include <linux/delay.h>
#include <linux/interrupt.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-v3.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;
};
struct gic_chip_data {
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;
};
static struct gic_chip_data gic_data __read_mostly;
static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
#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 ^ (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
irqchip/gic: Ensure ordering between read of INTACK and shared data commit f86c4fbd930ff6fecf3d8a1c313182bd0f49f496 upstream. When an IPI is generated by a CPU, the pattern looks roughly like: <write shared data> smp_wmb(); <write to GIC to signal SGI> On the receiving CPU we rely on the fact that, once we've taken the interrupt, then the freshly written shared data must be visible to us. Put another way, the CPU isn't going to speculate taking an interrupt. Unfortunately, this assumption turns out to be broken. Consider that CPUx wants to send an IPI to CPUy, which will cause CPUy to read some shared_data. Before CPUx has done anything, a random peripheral raises an IRQ to the GIC and the IRQ line on CPUy is raised. CPUy then takes the IRQ and starts executing the entry code, heading towards gic_handle_irq. Furthermore, let's assume that a bunch of the previous interrupts handled by CPUy were SGIs, so the branch predictor kicks in and speculates that irqnr will be <16 and we're likely to head into handle_IPI. The prefetcher then grabs a speculative copy of shared_data which contains a stale value. Meanwhile, CPUx gets round to updating shared_data and asking the GIC to send an SGI to CPUy. Internally, the GIC decides that the SGI is more important than the peripheral interrupt (which hasn't yet been ACKed) but doesn't need to do anything to CPUy, because the IRQ line is already raised. CPUy then reads the ACK register on the GIC, sees the SGI value which confirms the branch prediction and we end up with a stale shared_data value. This patch fixes the problem by adding an smp_rmb() to the IPI entry code in gic_handle_irq. As it turns out, the combination of a control dependency and an ISB instruction from the EOI in the GICv3 driver is enough to provide the ordering we need, so we add a comment there justifying the absence of an explicit smp_rmb(). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-26 12:00:00 +01:00
/*
* 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_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_secondary_init(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
gic_cpu_init();
return NOTIFY_OK;
}
/*
* Notifier for enabling the GIC CPU interface. Set an arbitrarily high
* priority because the GIC needs to be up before the ARM generic timers.
*/
static struct notifier_block gic_cpu_notifier = {
.notifier_call = gic_secondary_init,
.priority = 100,
};
static u16 gic_compute_target_list(int *base_cpu, const struct cpumask *mask,
unsigned long cluster_id)
{
irqchip/gicv3: Silence noisy DEBUG_PER_CPU_MAPS warning commit 727653d6ce7103b245eb8041f55dd5885f4c3289 upstream. gic_raise_softirq() walks the list of cpus using for_each_cpu(), it calls gic_compute_target_list() which advances the iterator by the number of CPUs in the cluster. If gic_compute_target_list() reaches the last CPU it leaves the iterator pointing at the last CPU. This means the next time round the for_each_cpu() loop cpumask_next() will be called with an invalid CPU. This triggers a warning when built with CONFIG_DEBUG_PER_CPU_MAPS: [ 3.077738] GICv3: CPU1: found redistributor 1 region 0:0x000000002f120000 [ 3.077943] CPU1: Booted secondary processor [410fd0f0] [ 3.078542] ------------[ cut here ]------------ [ 3.078746] WARNING: CPU: 1 PID: 0 at ../include/linux/cpumask.h:121 gic_raise_softirq+0x12c/0x170 [ 3.078812] Modules linked in: [ 3.078869] [ 3.078930] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.8.0-rc5+ #5188 [ 3.078994] Hardware name: Foundation-v8A (DT) [ 3.079059] task: ffff80087a1a0080 task.stack: ffff80087a19c000 [ 3.079145] PC is at gic_raise_softirq+0x12c/0x170 [ 3.079226] LR is at gic_raise_softirq+0xa4/0x170 [ 3.079296] pc : [<ffff0000083ead24>] lr : [<ffff0000083eac9c>] pstate: 200001c9 [ 3.081139] Call trace: [ 3.081202] Exception stack(0xffff80087a19fbe0 to 0xffff80087a19fd10) [ 3.082269] [<ffff0000083ead24>] gic_raise_softirq+0x12c/0x170 [ 3.082354] [<ffff00000808e614>] smp_send_reschedule+0x34/0x40 [ 3.082433] [<ffff0000080e80a0>] resched_curr+0x50/0x88 [ 3.082512] [<ffff0000080e89d0>] check_preempt_curr+0x60/0xd0 [ 3.082593] [<ffff0000080e8a60>] ttwu_do_wakeup+0x20/0xe8 [ 3.082672] [<ffff0000080e8bb8>] ttwu_do_activate+0x90/0xc0 [ 3.082753] [<ffff0000080ea9a4>] try_to_wake_up+0x224/0x370 [ 3.082836] [<ffff0000080eabc8>] default_wake_function+0x10/0x18 [ 3.082920] [<ffff000008103134>] __wake_up_common+0x5c/0xa0 [ 3.083003] [<ffff0000081031f4>] __wake_up_locked+0x14/0x20 [ 3.083086] [<ffff000008103f80>] complete+0x40/0x60 [ 3.083168] [<ffff00000808df7c>] secondary_start_kernel+0x15c/0x1d0 [ 3.083240] [<00000000808911a4>] 0x808911a4 [ 3.113401] Detected PIPT I-cache on CPU2 Avoid updating the iterator if the next call to cpumask_next() would cause the for_each_cpu() loop to exit. There is no change to gic_raise_softirq()'s behaviour, (cpumask_next()s eventual call to _find_next_bit() will return early as start >= nbits), this patch just silences the warning. Fixes: 021f653791ad ("irqchip: gic-v3: Initial support for GICv3") Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Jason Cooper <jason@lakedaemon.net> Link: http://lkml.kernel.org/r/1474306155-3303-1-git-send-email-james.morse@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-19 18:29:15 +01:00
int next_cpu, 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);
irqchip/gicv3: Silence noisy DEBUG_PER_CPU_MAPS warning commit 727653d6ce7103b245eb8041f55dd5885f4c3289 upstream. gic_raise_softirq() walks the list of cpus using for_each_cpu(), it calls gic_compute_target_list() which advances the iterator by the number of CPUs in the cluster. If gic_compute_target_list() reaches the last CPU it leaves the iterator pointing at the last CPU. This means the next time round the for_each_cpu() loop cpumask_next() will be called with an invalid CPU. This triggers a warning when built with CONFIG_DEBUG_PER_CPU_MAPS: [ 3.077738] GICv3: CPU1: found redistributor 1 region 0:0x000000002f120000 [ 3.077943] CPU1: Booted secondary processor [410fd0f0] [ 3.078542] ------------[ cut here ]------------ [ 3.078746] WARNING: CPU: 1 PID: 0 at ../include/linux/cpumask.h:121 gic_raise_softirq+0x12c/0x170 [ 3.078812] Modules linked in: [ 3.078869] [ 3.078930] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.8.0-rc5+ #5188 [ 3.078994] Hardware name: Foundation-v8A (DT) [ 3.079059] task: ffff80087a1a0080 task.stack: ffff80087a19c000 [ 3.079145] PC is at gic_raise_softirq+0x12c/0x170 [ 3.079226] LR is at gic_raise_softirq+0xa4/0x170 [ 3.079296] pc : [<ffff0000083ead24>] lr : [<ffff0000083eac9c>] pstate: 200001c9 [ 3.081139] Call trace: [ 3.081202] Exception stack(0xffff80087a19fbe0 to 0xffff80087a19fd10) [ 3.082269] [<ffff0000083ead24>] gic_raise_softirq+0x12c/0x170 [ 3.082354] [<ffff00000808e614>] smp_send_reschedule+0x34/0x40 [ 3.082433] [<ffff0000080e80a0>] resched_curr+0x50/0x88 [ 3.082512] [<ffff0000080e89d0>] check_preempt_curr+0x60/0xd0 [ 3.082593] [<ffff0000080e8a60>] ttwu_do_wakeup+0x20/0xe8 [ 3.082672] [<ffff0000080e8bb8>] ttwu_do_activate+0x90/0xc0 [ 3.082753] [<ffff0000080ea9a4>] try_to_wake_up+0x224/0x370 [ 3.082836] [<ffff0000080eabc8>] default_wake_function+0x10/0x18 [ 3.082920] [<ffff000008103134>] __wake_up_common+0x5c/0xa0 [ 3.083003] [<ffff0000081031f4>] __wake_up_locked+0x14/0x20 [ 3.083086] [<ffff000008103f80>] complete+0x40/0x60 [ 3.083168] [<ffff00000808df7c>] secondary_start_kernel+0x15c/0x1d0 [ 3.083240] [<00000000808911a4>] 0x808911a4 [ 3.113401] Detected PIPT I-cache on CPU2 Avoid updating the iterator if the next call to cpumask_next() would cause the for_each_cpu() loop to exit. There is no change to gic_raise_softirq()'s behaviour, (cpumask_next()s eventual call to _find_next_bit() will return early as start >= nbits), this patch just silences the warning. Fixes: 021f653791ad ("irqchip: gic-v3: Initial support for GICv3") Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Jason Cooper <jason@lakedaemon.net> Link: http://lkml.kernel.org/r/1474306155-3303-1-git-send-email-james.morse@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-19 18:29:15 +01:00
next_cpu = cpumask_next(cpu, mask);
if (next_cpu >= nr_cpu_ids)
goto out;
irqchip/gicv3: Silence noisy DEBUG_PER_CPU_MAPS warning commit 727653d6ce7103b245eb8041f55dd5885f4c3289 upstream. gic_raise_softirq() walks the list of cpus using for_each_cpu(), it calls gic_compute_target_list() which advances the iterator by the number of CPUs in the cluster. If gic_compute_target_list() reaches the last CPU it leaves the iterator pointing at the last CPU. This means the next time round the for_each_cpu() loop cpumask_next() will be called with an invalid CPU. This triggers a warning when built with CONFIG_DEBUG_PER_CPU_MAPS: [ 3.077738] GICv3: CPU1: found redistributor 1 region 0:0x000000002f120000 [ 3.077943] CPU1: Booted secondary processor [410fd0f0] [ 3.078542] ------------[ cut here ]------------ [ 3.078746] WARNING: CPU: 1 PID: 0 at ../include/linux/cpumask.h:121 gic_raise_softirq+0x12c/0x170 [ 3.078812] Modules linked in: [ 3.078869] [ 3.078930] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.8.0-rc5+ #5188 [ 3.078994] Hardware name: Foundation-v8A (DT) [ 3.079059] task: ffff80087a1a0080 task.stack: ffff80087a19c000 [ 3.079145] PC is at gic_raise_softirq+0x12c/0x170 [ 3.079226] LR is at gic_raise_softirq+0xa4/0x170 [ 3.079296] pc : [<ffff0000083ead24>] lr : [<ffff0000083eac9c>] pstate: 200001c9 [ 3.081139] Call trace: [ 3.081202] Exception stack(0xffff80087a19fbe0 to 0xffff80087a19fd10) [ 3.082269] [<ffff0000083ead24>] gic_raise_softirq+0x12c/0x170 [ 3.082354] [<ffff00000808e614>] smp_send_reschedule+0x34/0x40 [ 3.082433] [<ffff0000080e80a0>] resched_curr+0x50/0x88 [ 3.082512] [<ffff0000080e89d0>] check_preempt_curr+0x60/0xd0 [ 3.082593] [<ffff0000080e8a60>] ttwu_do_wakeup+0x20/0xe8 [ 3.082672] [<ffff0000080e8bb8>] ttwu_do_activate+0x90/0xc0 [ 3.082753] [<ffff0000080ea9a4>] try_to_wake_up+0x224/0x370 [ 3.082836] [<ffff0000080eabc8>] default_wake_function+0x10/0x18 [ 3.082920] [<ffff000008103134>] __wake_up_common+0x5c/0xa0 [ 3.083003] [<ffff0000081031f4>] __wake_up_locked+0x14/0x20 [ 3.083086] [<ffff000008103f80>] complete+0x40/0x60 [ 3.083168] [<ffff00000808df7c>] secondary_start_kernel+0x15c/0x1d0 [ 3.083240] [<00000000808911a4>] 0x808911a4 [ 3.113401] Detected PIPT I-cache on CPU2 Avoid updating the iterator if the next call to cpumask_next() would cause the for_each_cpu() loop to exit. There is no change to gic_raise_softirq()'s behaviour, (cpumask_next()s eventual call to _find_next_bit() will return early as start >= nbits), this patch just silences the warning. Fixes: 021f653791ad ("irqchip: gic-v3: Initial support for GICv3") Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Jason Cooper <jason@lakedaemon.net> Link: http://lkml.kernel.org/r/1474306155-3303-1-git-send-email-james.morse@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-19 18:29:15 +01:00
cpu = next_cpu;
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);
register_cpu_notifier(&gic_cpu_notifier);
}
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;
}
#else
#define gic_set_affinity NULL
#define gic_smp_init() do { } while(0)
#endif
#ifdef CONFIG_CPU_PM
static int gic_cpu_pm_notifier(struct notifier_block *self,
unsigned long cmd, void *v)
{
if (cmd == CPU_PM_EXIT) {
gic_enable_redist(true);
gic_cpu_sys_reg_init();
} else if (cmd == CPU_PM_ENTER) {
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;
}
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 const struct irq_domain_ops gic_irq_domain_ops = {
.translate = gic_irq_domain_translate,
.alloc = gic_irq_domain_alloc,
.free = gic_irq_domain_free,
};
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_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;
u32 typer;
u32 reg;
int gic_irqs;
int err;
int 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;
}
reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
if (reg != GIC_PIDR2_ARCH_GICv3 && reg != GIC_PIDR2_ARCH_GICv4) {
pr_err("%s: no distributor detected, giving up\n",
node->full_name);
err = -ENODEV;
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;
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.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_add_tree(node, &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);
if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
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);
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);