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-rw-r--r--arch/arm/kvm/arm.c30
-rw-r--r--arch/arm64/Kconfig15
-rw-r--r--arch/arm64/include/asm/Kbuild1
-rw-r--r--arch/arm64/include/asm/cpu_ops.h6
-rw-r--r--arch/arm64/include/asm/cputype.h10
-rw-r--r--arch/arm64/include/asm/hardirq.h2
-rw-r--r--arch/arm64/include/asm/percpu.h41
-rw-r--r--arch/arm64/include/asm/proc-fns.h3
-rw-r--r--arch/arm64/include/asm/smp_plat.h13
-rw-r--r--arch/arm64/include/asm/suspend.h27
-rw-r--r--arch/arm64/kernel/Makefile1
-rw-r--r--arch/arm64/kernel/asm-offsets.c44
-rw-r--r--arch/arm64/kernel/fpsimd.c63
-rw-r--r--arch/arm64/kernel/hw_breakpoint.c203
-rw-r--r--arch/arm64/kernel/process.c7
-rw-r--r--arch/arm64/kernel/setup.c80
-rw-r--r--arch/arm64/kernel/sleep.S184
-rw-r--r--arch/arm64/kernel/smp.c23
-rw-r--r--arch/arm64/kernel/suspend.c140
-rw-r--r--arch/arm64/mm/proc.S69
20 files changed, 889 insertions, 73 deletions
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index ef1703b9587b..1d55afe7fd4b 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -17,6 +17,7 @@
*/
#include <linux/cpu.h>
+#include <linux/cpu_pm.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
@@ -835,6 +836,33 @@ static struct notifier_block hyp_init_cpu_nb = {
.notifier_call = hyp_init_cpu_notify,
};
+#ifdef CONFIG_CPU_PM
+static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
+ unsigned long cmd,
+ void *v)
+{
+ if (cmd == CPU_PM_EXIT) {
+ cpu_init_hyp_mode(NULL);
+ return NOTIFY_OK;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block hyp_init_cpu_pm_nb = {
+ .notifier_call = hyp_init_cpu_pm_notifier,
+};
+
+static void __init hyp_cpu_pm_init(void)
+{
+ cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
+}
+#else
+static inline void hyp_cpu_pm_init(void)
+{
+}
+#endif
+
/**
* Inits Hyp-mode on all online CPUs
*/
@@ -995,6 +1023,8 @@ int kvm_arch_init(void *opaque)
goto out_err;
}
+ hyp_cpu_pm_init();
+
kvm_coproc_table_init();
return 0;
out_err:
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a95dc907a139..419ef44324f3 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1,6 +1,8 @@
config ARM64
def_bool y
select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
+ select ARCH_USE_CMPXCHG_LOCKREF
+ select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_WANT_OPTIONAL_GPIOLIB
select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
select ARCH_WANT_FRAME_POINTERS
@@ -9,7 +11,9 @@ config ARM64
select ARM_GIC
select CLONE_BACKWARDS
select COMMON_CLK
+ select CPU_PM if (SUSPEND || CPU_IDLE)
select GENERIC_CLOCKEVENTS
+ select GENERIC_CLOCKEVENTS_BROADCAST if SMP
select GENERIC_IOMAP
select GENERIC_IRQ_PROBE
select GENERIC_IRQ_SHOW
@@ -361,6 +365,17 @@ menu "Power management options"
source "kernel/power/Kconfig"
source "drivers/cpufreq/Kconfig"
+config ARCH_SUSPEND_POSSIBLE
+ def_bool y
+
+config ARM64_CPU_SUSPEND
+ def_bool PM_SLEEP
+
+endmenu
+
+menu "CPU Power Management"
+
+source "drivers/cpuidle/Kconfig"
endmenu
diff --git a/arch/arm64/include/asm/Kbuild b/arch/arm64/include/asm/Kbuild
index 79a642d199f2..ae0612c4fa45 100644
--- a/arch/arm64/include/asm/Kbuild
+++ b/arch/arm64/include/asm/Kbuild
@@ -26,7 +26,6 @@ generic-y += mman.h
generic-y += msgbuf.h
generic-y += mutex.h
generic-y += pci.h
-generic-y += percpu.h
generic-y += poll.h
generic-y += posix_types.h
generic-y += resource.h
diff --git a/arch/arm64/include/asm/cpu_ops.h b/arch/arm64/include/asm/cpu_ops.h
index c4cdb5e5b73d..152413076503 100644
--- a/arch/arm64/include/asm/cpu_ops.h
+++ b/arch/arm64/include/asm/cpu_ops.h
@@ -39,6 +39,9 @@ struct device_node;
* from the cpu to be killed.
* @cpu_die: Makes a cpu leave the kernel. Must not fail. Called from the
* cpu being killed.
+ * @cpu_suspend: Suspends a cpu and saves the required context. May fail owing
+ * to wrong parameters or error conditions. Called from the
+ * CPU being suspended. Must be called with IRQs disabled.
*/
struct cpu_operations {
const char *name;
@@ -50,6 +53,9 @@ struct cpu_operations {
int (*cpu_disable)(unsigned int cpu);
void (*cpu_die)(unsigned int cpu);
#endif
+#ifdef CONFIG_ARM64_CPU_SUSPEND
+ int (*cpu_suspend)(unsigned long);
+#endif
};
extern const struct cpu_operations *cpu_ops[NR_CPUS];
diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h
index cf2749488cd4..a8053d89512f 100644
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -30,6 +30,16 @@
#define MPIDR_HWID_BITMASK 0xff00ffffff
+#define MPIDR_LEVEL_BITS_SHIFT 3
+#define MPIDR_LEVEL_BITS (1 << MPIDR_LEVEL_BITS_SHIFT)
+#define MPIDR_LEVEL_MASK ((1 << MPIDR_LEVEL_BITS) - 1)
+
+#define MPIDR_LEVEL_SHIFT(level) \
+ (((1 << level) >> 1) << MPIDR_LEVEL_BITS_SHIFT)
+
+#define MPIDR_AFFINITY_LEVEL(mpidr, level) \
+ ((mpidr >> MPIDR_LEVEL_SHIFT(level)) & MPIDR_LEVEL_MASK)
+
#define read_cpuid(reg) ({ \
u64 __val; \
asm("mrs %0, " reg : "=r" (__val)); \
diff --git a/arch/arm64/include/asm/hardirq.h b/arch/arm64/include/asm/hardirq.h
index 990c051e7829..ae4801d77514 100644
--- a/arch/arm64/include/asm/hardirq.h
+++ b/arch/arm64/include/asm/hardirq.h
@@ -20,7 +20,7 @@
#include <linux/threads.h>
#include <asm/irq.h>
-#define NR_IPI 4
+#define NR_IPI 5
typedef struct {
unsigned int __softirq_pending;
diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h
new file mode 100644
index 000000000000..13fb0b3efc5f
--- /dev/null
+++ b/arch/arm64/include/asm/percpu.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2013 ARM Ltd.
+ *
+ * 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/>.
+ */
+#ifndef __ASM_PERCPU_H
+#define __ASM_PERCPU_H
+
+static inline void set_my_cpu_offset(unsigned long off)
+{
+ asm volatile("msr tpidr_el1, %0" :: "r" (off) : "memory");
+}
+
+static inline unsigned long __my_cpu_offset(void)
+{
+ unsigned long off;
+ register unsigned long *sp asm ("sp");
+
+ /*
+ * We want to allow caching the value, so avoid using volatile and
+ * instead use a fake stack read to hazard against barrier().
+ */
+ asm("mrs %0, tpidr_el1" : "=r" (off) : "Q" (*sp));
+
+ return off;
+}
+#define __my_cpu_offset __my_cpu_offset()
+
+#include <asm-generic/percpu.h>
+
+#endif /* __ASM_PERCPU_H */
diff --git a/arch/arm64/include/asm/proc-fns.h b/arch/arm64/include/asm/proc-fns.h
index 7cdf466fd0c5..0c657bb54597 100644
--- a/arch/arm64/include/asm/proc-fns.h
+++ b/arch/arm64/include/asm/proc-fns.h
@@ -26,11 +26,14 @@
#include <asm/page.h>
struct mm_struct;
+struct cpu_suspend_ctx;
extern void cpu_cache_off(void);
extern void cpu_do_idle(void);
extern void cpu_do_switch_mm(unsigned long pgd_phys, struct mm_struct *mm);
extern void cpu_reset(unsigned long addr) __attribute__((noreturn));
+extern void cpu_do_suspend(struct cpu_suspend_ctx *ptr);
+extern u64 cpu_do_resume(phys_addr_t ptr, u64 idmap_ttbr);
#include <asm/memory.h>
diff --git a/arch/arm64/include/asm/smp_plat.h b/arch/arm64/include/asm/smp_plat.h
index ed43a0d2b1b2..59e282311b58 100644
--- a/arch/arm64/include/asm/smp_plat.h
+++ b/arch/arm64/include/asm/smp_plat.h
@@ -21,6 +21,19 @@
#include <asm/types.h>
+struct mpidr_hash {
+ u64 mask;
+ u32 shift_aff[4];
+ u32 bits;
+};
+
+extern struct mpidr_hash mpidr_hash;
+
+static inline u32 mpidr_hash_size(void)
+{
+ return 1 << mpidr_hash.bits;
+}
+
/*
* Logical CPU mapping.
*/
diff --git a/arch/arm64/include/asm/suspend.h b/arch/arm64/include/asm/suspend.h
new file mode 100644
index 000000000000..e9c149c042e0
--- /dev/null
+++ b/arch/arm64/include/asm/suspend.h
@@ -0,0 +1,27 @@
+#ifndef __ASM_SUSPEND_H
+#define __ASM_SUSPEND_H
+
+#define NR_CTX_REGS 11
+
+/*
+ * struct cpu_suspend_ctx must be 16-byte aligned since it is allocated on
+ * the stack, which must be 16-byte aligned on v8
+ */
+struct cpu_suspend_ctx {
+ /*
+ * This struct must be kept in sync with
+ * cpu_do_{suspend/resume} in mm/proc.S
+ */
+ u64 ctx_regs[NR_CTX_REGS];
+ u64 sp;
+} __aligned(16);
+
+struct sleep_save_sp {
+ phys_addr_t *save_ptr_stash;
+ phys_addr_t save_ptr_stash_phys;
+};
+
+extern void cpu_resume(void);
+extern int cpu_suspend(unsigned long);
+
+#endif
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 2d145e38ad49..c6172392b20d 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -19,6 +19,7 @@ arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o
arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o
arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
arm64-obj-$(CONFIG_ARM_CPU_TOPOLOGY) += topology.o
+arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o
obj-y += $(arm64-obj-y) vdso/
obj-m += $(arm64-obj-m)
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index a2a4d810bea3..c481a119b98a 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -24,6 +24,8 @@
#include <asm/thread_info.h>
#include <asm/memory.h>
#include <asm/cputable.h>
+#include <asm/smp_plat.h>
+#include <asm/suspend.h>
#include <asm/vdso_datapage.h>
#include <linux/kbuild.h>
@@ -104,5 +106,47 @@ int main(void)
BLANK();
DEFINE(TZ_MINWEST, offsetof(struct timezone, tz_minuteswest));
DEFINE(TZ_DSTTIME, offsetof(struct timezone, tz_dsttime));
+ BLANK();
+#ifdef CONFIG_KVM_ARM_HOST
+ DEFINE(VCPU_CONTEXT, offsetof(struct kvm_vcpu, arch.ctxt));
+ DEFINE(CPU_GP_REGS, offsetof(struct kvm_cpu_context, gp_regs));
+ DEFINE(CPU_USER_PT_REGS, offsetof(struct kvm_regs, regs));
+ DEFINE(CPU_FP_REGS, offsetof(struct kvm_regs, fp_regs));
+ DEFINE(CPU_SP_EL1, offsetof(struct kvm_regs, sp_el1));
+ DEFINE(CPU_ELR_EL1, offsetof(struct kvm_regs, elr_el1));
+ DEFINE(CPU_SPSR, offsetof(struct kvm_regs, spsr));
+ DEFINE(CPU_SYSREGS, offsetof(struct kvm_cpu_context, sys_regs));
+ DEFINE(VCPU_ESR_EL2, offsetof(struct kvm_vcpu, arch.fault.esr_el2));
+ DEFINE(VCPU_FAR_EL2, offsetof(struct kvm_vcpu, arch.fault.far_el2));
+ DEFINE(VCPU_HPFAR_EL2, offsetof(struct kvm_vcpu, arch.fault.hpfar_el2));
+ DEFINE(VCPU_HCR_EL2, offsetof(struct kvm_vcpu, arch.hcr_el2));
+ DEFINE(VCPU_IRQ_LINES, offsetof(struct kvm_vcpu, arch.irq_lines));
+ DEFINE(VCPU_HOST_CONTEXT, offsetof(struct kvm_vcpu, arch.host_cpu_context));
+ DEFINE(VCPU_TIMER_CNTV_CTL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_ctl));
+ DEFINE(VCPU_TIMER_CNTV_CVAL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_cval));
+ DEFINE(KVM_TIMER_CNTVOFF, offsetof(struct kvm, arch.timer.cntvoff));
+ DEFINE(KVM_TIMER_ENABLED, offsetof(struct kvm, arch.timer.enabled));
+ DEFINE(VCPU_KVM, offsetof(struct kvm_vcpu, kvm));
+ DEFINE(VCPU_VGIC_CPU, offsetof(struct kvm_vcpu, arch.vgic_cpu));
+ DEFINE(VGIC_CPU_HCR, offsetof(struct vgic_cpu, vgic_hcr));
+ DEFINE(VGIC_CPU_VMCR, offsetof(struct vgic_cpu, vgic_vmcr));
+ DEFINE(VGIC_CPU_MISR, offsetof(struct vgic_cpu, vgic_misr));
+ DEFINE(VGIC_CPU_EISR, offsetof(struct vgic_cpu, vgic_eisr));
+ DEFINE(VGIC_CPU_ELRSR, offsetof(struct vgic_cpu, vgic_elrsr));
+ DEFINE(VGIC_CPU_APR, offsetof(struct vgic_cpu, vgic_apr));
+ DEFINE(VGIC_CPU_LR, offsetof(struct vgic_cpu, vgic_lr));
+ DEFINE(VGIC_CPU_NR_LR, offsetof(struct vgic_cpu, nr_lr));
+ DEFINE(KVM_VTTBR, offsetof(struct kvm, arch.vttbr));
+ DEFINE(KVM_VGIC_VCTRL, offsetof(struct kvm, arch.vgic.vctrl_base));
+#endif
+#ifdef CONFIG_ARM64_CPU_SUSPEND
+ DEFINE(CPU_SUSPEND_SZ, sizeof(struct cpu_suspend_ctx));
+ DEFINE(CPU_CTX_SP, offsetof(struct cpu_suspend_ctx, sp));
+ DEFINE(MPIDR_HASH_MASK, offsetof(struct mpidr_hash, mask));
+ DEFINE(MPIDR_HASH_SHIFTS, offsetof(struct mpidr_hash, shift_aff));
+ DEFINE(SLEEP_SAVE_SP_SZ, sizeof(struct sleep_save_sp));
+ DEFINE(SLEEP_SAVE_SP_PHYS, offsetof(struct sleep_save_sp, save_ptr_stash_phys));
+ DEFINE(SLEEP_SAVE_SP_VIRT, offsetof(struct sleep_save_sp, save_ptr_stash));
+#endif
return 0;
}
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index 2fa308e4a1fa..522df9c7f3a4 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -17,6 +17,7 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <linux/cpu_pm.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/sched.h>
@@ -85,6 +86,66 @@ void fpsimd_flush_thread(void)
preempt_enable();
}
+#ifdef CONFIG_KERNEL_MODE_NEON
+
+/*
+ * Kernel-side NEON support functions
+ */
+void kernel_neon_begin(void)
+{
+ /* Avoid using the NEON in interrupt context */
+ BUG_ON(in_interrupt());
+ preempt_disable();
+
+ if (current->mm)
+ fpsimd_save_state(&current->thread.fpsimd_state);
+}
+EXPORT_SYMBOL(kernel_neon_begin);
+
+void kernel_neon_end(void)
+{
+ if (current->mm)
+ fpsimd_load_state(&current->thread.fpsimd_state);
+
+ preempt_enable();
+}
+EXPORT_SYMBOL(kernel_neon_end);
+
+#endif /* CONFIG_KERNEL_MODE_NEON */
+
+#ifdef CONFIG_CPU_PM
+static int fpsimd_cpu_pm_notifier(struct notifier_block *self,
+ unsigned long cmd, void *v)
+{
+ switch (cmd) {
+ case CPU_PM_ENTER:
+ if (current->mm)
+ fpsimd_save_state(&current->thread.fpsimd_state);
+ break;
+ case CPU_PM_EXIT:
+ if (current->mm)
+ fpsimd_load_state(&current->thread.fpsimd_state);
+ break;
+ case CPU_PM_ENTER_FAILED:
+ default:
+ return NOTIFY_DONE;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block fpsimd_cpu_pm_notifier_block = {
+ .notifier_call = fpsimd_cpu_pm_notifier,
+};
+
+static void fpsimd_pm_init(void)
+{
+ cpu_pm_register_notifier(&fpsimd_cpu_pm_notifier_block);
+}
+
+#else
+static inline void fpsimd_pm_init(void) { }
+#endif /* CONFIG_CPU_PM */
+
/*
* FP/SIMD support code initialisation.
*/
@@ -103,6 +164,8 @@ static int __init fpsimd_init(void)
else
elf_hwcap |= HWCAP_ASIMD;
+ fpsimd_pm_init();
+
return 0;
}
late_initcall(fpsimd_init);
diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c
index 5ab825c59db9..b989233a9d31 100644
--- a/arch/arm64/kernel/hw_breakpoint.c
+++ b/arch/arm64/kernel/hw_breakpoint.c
@@ -20,6 +20,7 @@
#define pr_fmt(fmt) "hw-breakpoint: " fmt
+#include <linux/cpu_pm.h>
#include <linux/errno.h>
#include <linux/hw_breakpoint.h>
#include <linux/perf_event.h>
@@ -169,15 +170,68 @@ static enum debug_el debug_exception_level(int privilege)
}
}
-/*
- * Install a perf counter breakpoint.
+enum hw_breakpoint_ops {
+ HW_BREAKPOINT_INSTALL,
+ HW_BREAKPOINT_UNINSTALL,
+ HW_BREAKPOINT_RESTORE
+};
+
+/**
+ * hw_breakpoint_slot_setup - Find and setup a perf slot according to
+ * operations
+ *
+ * @slots: pointer to array of slots
+ * @max_slots: max number of slots
+ * @bp: perf_event to setup
+ * @ops: operation to be carried out on the slot
+ *
+ * Return:
+ * slot index on success
+ * -ENOSPC if no slot is available/matches
+ * -EINVAL on wrong operations parameter
*/
-int arch_install_hw_breakpoint(struct perf_event *bp)
+static int hw_breakpoint_slot_setup(struct perf_event **slots, int max_slots,
+ struct perf_event *bp,
+ enum hw_breakpoint_ops ops)
+{
+ int i;
+ struct perf_event **slot;
+
+ for (i = 0; i < max_slots; ++i) {
+ slot = &slots[i];
+ switch (ops) {
+ case HW_BREAKPOINT_INSTALL:
+ if (!*slot) {
+ *slot = bp;
+ return i;
+ }
+ break;
+ case HW_BREAKPOINT_UNINSTALL:
+ if (*slot == bp) {
+ *slot = NULL;
+ return i;
+ }
+ break;
+ case HW_BREAKPOINT_RESTORE:
+ if (*slot == bp)
+ return i;
+ break;
+ default:
+ pr_warn_once("Unhandled hw breakpoint ops %d\n", ops);
+ return -EINVAL;
+ }
+ }
+ return -ENOSPC;
+}
+
+static int hw_breakpoint_control(struct perf_event *bp,
+ enum hw_breakpoint_ops ops)
{
struct arch_hw_breakpoint *info = counter_arch_bp(bp);
- struct perf_event **slot, **slots;
+ struct perf_event **slots;
struct debug_info *debug_info = &current->thread.debug;
int i, max_slots, ctrl_reg, val_reg, reg_enable;
+ enum debug_el dbg_el = debug_exception_level(info->ctrl.privilege);
u32 ctrl;
if (info->ctrl.type == ARM_BREAKPOINT_EXECUTE) {
@@ -196,67 +250,54 @@ int arch_install_hw_breakpoint(struct perf_event *bp)
reg_enable = !debug_info->wps_disabled;
}
- for (i = 0; i < max_slots; ++i) {
- slot = &slots[i];
-
- if (!*slot) {
- *slot = bp;
- break;
- }
- }
-
- if (WARN_ONCE(i == max_slots, "Can't find any breakpoint slot"))
- return -ENOSPC;
+ i = hw_breakpoint_slot_setup(slots, max_slots, bp, ops);
- /* Ensure debug monitors are enabled at the correct exception level. */
- enable_debug_monitors(debug_exception_level(info->ctrl.privilege));
+ if (WARN_ONCE(i < 0, "Can't find any breakpoint slot"))
+ return i;
- /* Setup the address register. */
- write_wb_reg(val_reg, i, info->address);
+ switch (ops) {
+ case HW_BREAKPOINT_INSTALL:
+ /*
+ * Ensure debug monitors are enabled at the correct exception
+ * level.
+ */
+ enable_debug_monitors(dbg_el);
+ /* Fall through */
+ case HW_BREAKPOINT_RESTORE:
+ /* Setup the address register. */
+ write_wb_reg(val_reg, i, info->address);
+
+ /* Setup the control register. */
+ ctrl = encode_ctrl_reg(info->ctrl);
+ write_wb_reg(ctrl_reg, i,
+ reg_enable ? ctrl | 0x1 : ctrl & ~0x1);
+ break;
+ case HW_BREAKPOINT_UNINSTALL:
+ /* Reset the control register. */
+ write_wb_reg(ctrl_reg, i, 0);
- /* Setup the control register. */
- ctrl = encode_ctrl_reg(info->ctrl);
- write_wb_reg(ctrl_reg, i, reg_enable ? ctrl | 0x1 : ctrl & ~0x1);
+ /*
+ * Release the debug monitors for the correct exception
+ * level.
+ */
+ disable_debug_monitors(dbg_el);
+ break;
+ }
return 0;
}
-void arch_uninstall_hw_breakpoint(struct perf_event *bp)
+/*
+ * Install a perf counter breakpoint.
+ */
+int arch_install_hw_breakpoint(struct perf_event *bp)
{
- struct arch_hw_breakpoint *info = counter_arch_bp(bp);
- struct perf_event **slot, **slots;
- int i, max_slots, base;
-
- if (info->ctrl.type == ARM_BREAKPOINT_EXECUTE) {
- /* Breakpoint */
- base = AARCH64_DBG_REG_BCR;
- slots = __get_cpu_var(bp_on_reg);
- max_slots = core_num_brps;
- } else {
- /* Watchpoint */
- base = AARCH64_DBG_REG_WCR;
- slots = __get_cpu_var(wp_on_reg);
- max_slots = core_num_wrps;
- }
-
- /* Remove the breakpoint. */
- for (i = 0; i < max_slots; ++i) {
- slot = &slots[i];
-
- if (*slot == bp) {
- *slot = NULL;
- break;
- }
- }
-
- if (WARN_ONCE(i == max_slots, "Can't find any breakpoint slot"))
- return;
-
- /* Reset the control register. */
- write_wb_reg(base, i, 0);
+ return hw_breakpoint_control(bp, HW_BREAKPOINT_INSTALL);
+}
- /* Release the debug monitors for the correct exception level. */
- disable_debug_monitors(debug_exception_level(info->ctrl.privilege));
+void arch_uninstall_hw_breakpoint(struct perf_event *bp)
+{
+ hw_breakpoint_control(bp, HW_BREAKPOINT_UNINSTALL);
}
static int get_hbp_len(u8 hbp_len)
@@ -806,18 +847,36 @@ void hw_breakpoint_thread_switch(struct task_struct *next)
/*
* CPU initialisation.
*/
-static void reset_ctrl_regs(void *unused)
+static void hw_breakpoint_reset(void *unused)
{
int i;
-
- for (i = 0; i < core_num_brps; ++i) {
- write_wb_reg(AARCH64_DBG_REG_BCR, i, 0UL);
- write_wb_reg(AARCH64_DBG_REG_BVR, i, 0UL);
+ struct perf_event **slots;
+ /*
+ * When a CPU goes through cold-boot, it does not have any installed
+ * slot, so it is safe to share the same function for restoring and
+ * resetting breakpoints; when a CPU is hotplugged in, it goes
+ * through the slots, which are all empty, hence it just resets control
+ * and value for debug registers.
+ * When this function is triggered on warm-boot through a CPU PM
+ * notifier some slots might be initialized; if so they are
+ * reprogrammed according to the debug slots content.
+ */
+ for (slots = __get_cpu_var(bp_on_reg), i = 0; i < core_num_brps; ++i) {
+ if (slots[i]) {
+ hw_breakpoint_control(slots[i], HW_BREAKPOINT_RESTORE);
+ } else {
+ write_wb_reg(AARCH64_DBG_REG_BCR, i, 0UL);
+ write_wb_reg(AARCH64_DBG_REG_BVR, i, 0UL);
+ }
}
- for (i = 0; i < core_num_wrps; ++i) {
- write_wb_reg(AARCH64_DBG_REG_WCR, i, 0UL);
- write_wb_reg(AARCH64_DBG_REG_WVR, i, 0UL);
+ for (slots = __get_cpu_var(wp_on_reg), i = 0; i < core_num_wrps; ++i) {
+ if (slots[i]) {
+ hw_breakpoint_control(slots[i], HW_BREAKPOINT_RESTORE);
+ } else {
+ write_wb_reg(AARCH64_DBG_REG_WCR, i, 0UL);
+ write_wb_reg(AARCH64_DBG_REG_WVR, i, 0UL);
+ }
}
}
@@ -827,7 +886,7 @@ static int __cpuinit hw_breakpoint_reset_notify(struct notifier_block *self,
{
int cpu = (long)hcpu;
if (action == CPU_ONLINE)
- smp_call_function_single(cpu, reset_ctrl_regs, NULL, 1);
+ smp_call_function_single(cpu, hw_breakpoint_reset, NULL, 1);
return NOTIFY_OK;
}
@@ -835,6 +894,14 @@ static struct notifier_block __cpuinitdata hw_breakpoint_reset_nb = {
.notifier_call = hw_breakpoint_reset_notify,
};
+#ifdef CONFIG_ARM64_CPU_SUSPEND
+extern void cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *));
+#else
+static inline void cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *))
+{
+}
+#endif
+
/*
* One-time initialisation.
*/
@@ -850,8 +917,8 @@ static int __init arch_hw_breakpoint_init(void)
* Reset the breakpoint resources. We assume that a halting
* debugger will leave the world in a nice state for us.
*/
- smp_call_function(reset_ctrl_regs, NULL, 1);
- reset_ctrl_regs(NULL);
+ smp_call_function(hw_breakpoint_reset, NULL, 1);
+ hw_breakpoint_reset(NULL);
/* Register debug fault handlers. */
hook_debug_fault_code(DBG_ESR_EVT_HWBP, breakpoint_handler, SIGTRAP,
@@ -861,6 +928,8 @@ static int __init arch_hw_breakpoint_init(void)
/* Register hotplug notifier. */
register_cpu_notifier(&hw_breakpoint_reset_nb);
+ /* Register cpu_suspend hw breakpoint restore hook */
+ cpu_suspend_set_dbg_restorer(hw_breakpoint_reset);
return 0;
}
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index 4caf198ca44f..8254875b67a0 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -33,6 +33,7 @@
#include <linux/kallsyms.h>
#include <linux/init.h>
#include <linux/cpu.h>
+#include <linux/cpuidle.h>
#include <linux/elfcore.h>
#include <linux/pm.h>
#include <linux/tick.h>
@@ -98,8 +99,10 @@ void arch_cpu_idle(void)
* This should do all the clock switching and wait for interrupt
* tricks
*/
- cpu_do_idle();
- local_irq_enable();
+ if (cpuidle_idle_call()) {
+ cpu_do_idle();
+ local_irq_enable();
+ }
}
#ifdef CONFIG_HOTPLUG_CPU
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 85afdae9cc05..cd8363447331 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -98,11 +98,90 @@ void __init early_print(const char *str, ...)
printk("%s", buf);
}
+void __init smp_setup_processor_id(void)
+{
+ /*
+ * clear __my_cpu_offset on boot CPU to avoid hang caused by
+ * using percpu variable early, for example, lockdep will
+ * access percpu variable inside lock_release
+ */
+ set_my_cpu_offset(0);
+}
+
bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
{
return phys_id == cpu_logical_map(cpu);
}
+struct mpidr_hash mpidr_hash;
+#ifdef CONFIG_SMP
+/**
+ * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
+ * level in order to build a linear index from an
+ * MPIDR value. Resulting algorithm is a collision
+ * free hash carried out through shifting and ORing
+ */
+static void __init smp_build_mpidr_hash(void)
+{
+ u32 i, affinity, fs[4], bits[4], ls;
+ u64 mask = 0;
+ /*
+ * Pre-scan the list of MPIDRS and filter out bits that do
+ * not contribute to affinity levels, ie they never toggle.
+ */
+ for_each_possible_cpu(i)
+ mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
+ pr_debug("mask of set bits %#llx\n", mask);
+ /*
+ * Find and stash the last and first bit set at all affinity levels to
+ * check how many bits are required to represent them.
+ */
+ for (i = 0; i < 4; i++) {
+ affinity = MPIDR_AFFINITY_LEVEL(mask, i);
+ /*
+ * Find the MSB bit and LSB bits position
+ * to determine how many bits are required
+ * to express the affinity level.
+ */
+ ls = fls(affinity);
+ fs[i] = affinity ? ffs(affinity) - 1 : 0;
+ bits[i] = ls - fs[i];
+ }
+ /*
+ * An index can be created from the MPIDR_EL1 by isolating the
+ * significant bits at each affinity level and by shifting
+ * them in order to compress the 32 bits values space to a
+ * compressed set of values. This is equivalent to hashing
+ * the MPIDR_EL1 through shifting and ORing. It is a collision free
+ * hash though not minimal since some levels might contain a number
+ * of CPUs that is not an exact power of 2 and their bit
+ * representation might contain holes, eg MPIDR_EL1[7:0] = {0x2, 0x80}.
+ */
+ mpidr_hash.shift_aff[0] = MPIDR_LEVEL_SHIFT(0) + fs[0];
+ mpidr_hash.shift_aff[1] = MPIDR_LEVEL_SHIFT(1) + fs[1] - bits[0];
+ mpidr_hash.shift_aff[2] = MPIDR_LEVEL_SHIFT(2) + fs[2] -
+ (bits[1] + bits[0]);
+ mpidr_hash.shift_aff[3] = MPIDR_LEVEL_SHIFT(3) +
+ fs[3] - (bits[2] + bits[1] + bits[0]);
+ mpidr_hash.mask = mask;
+ mpidr_hash.bits = bits[3] + bits[2] + bits[1] + bits[0];
+ pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] aff3[%u] mask[%#llx] bits[%u]\n",
+ mpidr_hash.shift_aff[0],
+ mpidr_hash.shift_aff[1],
+ mpidr_hash.shift_aff[2],
+ mpidr_hash.shift_aff[3],
+ mpidr_hash.mask,
+ mpidr_hash.bits);
+ /*
+ * 4x is an arbitrary value used to warn on a hash table much bigger
+ * than expected on most systems.
+ */
+ if (mpidr_hash_size() > 4 * num_possible_cpus())
+ pr_warn("Large number of MPIDR hash buckets detected\n");
+ __flush_dcache_area(&mpidr_hash, sizeof(struct mpidr_hash));
+}
+#endif
+
static void __init setup_processor(void)
{
struct cpu_info *cpu_info;
@@ -278,6 +357,7 @@ void __init setup_arch(char **cmdline_p)
cpu_read_bootcpu_ops();
#ifdef CONFIG_SMP
smp_init_cpus();
+ smp_build_mpidr_hash();
#endif
#ifdef CONFIG_VT
diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S
new file mode 100644
index 000000000000..b1925729c692
--- /dev/null
+++ b/arch/arm64/kernel/sleep.S
@@ -0,0 +1,184 @@
+#include <linux/errno.h>
+#include <linux/linkage.h>
+#include <asm/asm-offsets.h>
+#include <asm/assembler.h>
+
+ .text
+/*
+ * Implementation of MPIDR_EL1 hash algorithm through shifting
+ * and OR'ing.
+ *
+ * @dst: register containing hash result
+ * @rs0: register containing affinity level 0 bit shift
+ * @rs1: register containing affinity level 1 bit shift
+ * @rs2: register containing affinity level 2 bit shift
+ * @rs3: register containing affinity level 3 bit shift
+ * @mpidr: register containing MPIDR_EL1 value
+ * @mask: register containing MPIDR mask
+ *
+ * Pseudo C-code:
+ *
+ *u32 dst;
+ *
+ *compute_mpidr_hash(u32 rs0, u32 rs1, u32 rs2, u32 rs3, u64 mpidr, u64 mask) {
+ * u32 aff0, aff1, aff2, aff3;
+ * u64 mpidr_masked = mpidr & mask;
+ * aff0 = mpidr_masked & 0xff;
+ * aff1 = mpidr_masked & 0xff00;
+ * aff2 = mpidr_masked & 0xff0000;
+ * aff2 = mpidr_masked & 0xff00000000;
+ * dst = (aff0 >> rs0 | aff1 >> rs1 | aff2 >> rs2 | aff3 >> rs3);
+ *}
+ * Input registers: rs0, rs1, rs2, rs3, mpidr, mask
+ * Output register: dst
+ * Note: input and output registers must be disjoint register sets
+ (eg: a macro instance with mpidr = x1 and dst = x1 is invalid)
+ */
+ .macro compute_mpidr_hash dst, rs0, rs1, rs2, rs3, mpidr, mask
+ and \mpidr, \mpidr, \mask // mask out MPIDR bits
+ and \dst, \mpidr, #0xff // mask=aff0
+ lsr \dst ,\dst, \rs0 // dst=aff0>>rs0
+ and \mask, \mpidr, #0xff00 // mask = aff1
+ lsr \mask ,\mask, \rs1
+ orr \dst, \dst, \mask // dst|=(aff1>>rs1)
+ and \mask, \mpidr, #0xff0000 // mask = aff2
+ lsr \mask ,\mask, \rs2
+ orr \dst, \dst, \mask // dst|=(aff2>>rs2)
+ and \mask, \mpidr, #0xff00000000 // mask = aff3
+ lsr \mask ,\mask, \rs3
+ orr \dst, \dst, \mask // dst|=(aff3>>rs3)
+ .endm
+/*
+ * Save CPU state for a suspend. This saves callee registers, and allocates
+ * space on the kernel stack to save the CPU specific registers + some
+ * other data for resume.
+ *
+ * x0 = suspend finisher argument
+ */
+ENTRY(__cpu_suspend)
+ stp x29, lr, [sp, #-96]!
+ stp x19, x20, [sp,#16]
+ stp x21, x22, [sp,#32]
+ stp x23, x24, [sp,#48]
+ stp x25, x26, [sp,#64]
+ stp x27, x28, [sp,#80]
+ mov x2, sp
+ sub sp, sp, #CPU_SUSPEND_SZ // allocate cpu_suspend_ctx
+ mov x1, sp
+ /*
+ * x1 now points to struct cpu_suspend_ctx allocated on the stack
+ */
+ str x2, [x1, #CPU_CTX_SP]
+ ldr x2, =sleep_save_sp
+ ldr x2, [x2, #SLEEP_SAVE_SP_VIRT]
+#ifdef CONFIG_SMP
+ mrs x7, mpidr_el1
+ ldr x9, =mpidr_hash
+ ldr x10, [x9, #MPIDR_HASH_MASK]
+ /*
+ * Following code relies on the struct mpidr_hash
+ * members size.
+ */
+ ldp w3, w4, [x9, #MPIDR_HASH_SHIFTS]
+ ldp w5, w6, [x9, #(MPIDR_HASH_SHIFTS + 8)]
+ compute_mpidr_hash x8, x3, x4, x5, x6, x7, x10
+ add x2, x2, x8, lsl #3
+#endif
+ bl __cpu_suspend_finisher
+ /*
+ * Never gets here, unless suspend fails.
+ * Successful cpu_suspend should return from cpu_resume, returning
+ * through this code path is considered an error
+ * If the return value is set to 0 force x0 = -EOPNOTSUPP
+ * to make sure a proper error condition is propagated
+ */
+ cmp x0, #0
+ mov x3, #-EOPNOTSUPP
+ csel x0, x3, x0, eq
+ add sp, sp, #CPU_SUSPEND_SZ // rewind stack pointer
+ ldp x19, x20, [sp, #16]
+ ldp x21, x22, [sp, #32]
+ ldp x23, x24, [sp, #48]
+ ldp x25, x26, [sp, #64]
+ ldp x27, x28, [sp, #80]
+ ldp x29, lr, [sp], #96
+ ret
+ENDPROC(__cpu_suspend)
+ .ltorg
+
+/*
+ * x0 must contain the sctlr value retrieved from restored context
+ */
+ENTRY(cpu_resume_mmu)
+ ldr x3, =cpu_resume_after_mmu
+ msr sctlr_el1, x0 // restore sctlr_el1
+ isb
+ br x3 // global jump to virtual address
+ENDPROC(cpu_resume_mmu)
+cpu_resume_after_mmu:
+ mov x0, #0 // return zero on success
+ ldp x19, x20, [sp, #16]
+ ldp x21, x22, [sp, #32]
+ ldp x23, x24, [sp, #48]
+ ldp x25, x26, [sp, #64]
+ ldp x27, x28, [sp, #80]
+ ldp x29, lr, [sp], #96
+ ret
+ENDPROC(cpu_resume_after_mmu)
+
+ .data
+ENTRY(cpu_resume)
+ bl el2_setup // if in EL2 drop to EL1 cleanly
+#ifdef CONFIG_SMP
+ mrs x1, mpidr_el1
+ adr x4, mpidr_hash_ptr
+ ldr x5, [x4]
+ add x8, x4, x5 // x8 = struct mpidr_hash phys address
+ /* retrieve mpidr_hash members to compute the hash */
+ ldr x2, [x8, #MPIDR_HASH_MASK]
+ ldp w3, w4, [x8, #MPIDR_HASH_SHIFTS]
+ ldp w5, w6, [x8, #(MPIDR_HASH_SHIFTS + 8)]
+ compute_mpidr_hash x7, x3, x4, x5, x6, x1, x2
+ /* x7 contains hash index, let's use it to grab context pointer */
+#else
+ mov x7, xzr
+#endif
+ adr x0, sleep_save_sp
+ ldr x0, [x0, #SLEEP_SAVE_SP_PHYS]
+ ldr x0, [x0, x7, lsl #3]
+ /* load sp from context */
+ ldr x2, [x0, #CPU_CTX_SP]
+ adr x1, sleep_idmap_phys
+ /* load physical address of identity map page table in x1 */
+ ldr x1, [x1]
+ mov sp, x2
+ /*
+ * cpu_do_resume expects x0 to contain context physical address
+ * pointer and x1 to contain physical address of 1:1 page tables
+ */
+ bl cpu_do_resume // PC relative jump, MMU off
+ b cpu_resume_mmu // Resume MMU, never returns
+ENDPROC(cpu_resume)
+
+ .align 3
+mpidr_hash_ptr:
+ /*
+ * offset of mpidr_hash symbol from current location
+ * used to obtain run-time mpidr_hash address with MMU off
+ */
+ .quad mpidr_hash - .
+/*
+ * physical address of identity mapped page tables
+ */
+ .type sleep_idmap_phys, #object
+ENTRY(sleep_idmap_phys)
+ .quad 0
+/*
+ * struct sleep_save_sp {
+ * phys_addr_t *save_ptr_stash;
+ * phys_addr_t save_ptr_stash_phys;
+ * };
+ */
+ .type sleep_save_sp, #object
+ENTRY(sleep_save_sp)
+ .space SLEEP_SAVE_SP_SZ // struct sleep_save_sp
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 35085d664598..bd68d67d7da4 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -64,6 +64,7 @@ enum ipi_msg_type {
IPI_CALL_FUNC,
IPI_CALL_FUNC_SINGLE,
IPI_CPU_STOP,
+ IPI_TIMER,
};
/*
@@ -130,8 +131,6 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
struct mm_struct *mm = &init_mm;
unsigned int cpu = smp_processor_id();
- printk("CPU%u: Booted secondary processor\n", cpu);
-
/*
* All kernel threads share the same mm context; grab a
* reference and switch to it.
@@ -140,6 +139,9 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
current->active_mm = mm;
cpumask_set_cpu(cpu, mm_cpumask(mm));
+ set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
+ printk("CPU%u: Booted secondary processor\n", cpu);
+
/*
* TTBR0 is only used for the identity mapping at this stage. Make it
* point to zero page to avoid speculatively fetching new entries.
@@ -284,6 +286,7 @@ void __init smp_cpus_done(unsigned int max_cpus)
void __init smp_prepare_boot_cpu(void)
{
+ set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
}
static void (*smp_cross_call)(const struct cpumask *, unsigned int);
@@ -465,6 +468,7 @@ static const char *ipi_types[NR_IPI] = {
S(IPI_CALL_FUNC, "Function call interrupts"),
S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"),
S(IPI_CPU_STOP, "CPU stop interrupts"),
+ S(IPI_TIMER, "Timer broadcast interrupts"),
};
void show_ipi_list(struct seq_file *p, int prec)
@@ -550,6 +554,14 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
irq_exit();
break;
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+ case IPI_TIMER:
+ irq_enter();
+ tick_receive_broadcast();
+ irq_exit();
+ break;
+#endif
+
default:
pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr);
break;
@@ -562,6 +574,13 @@ void smp_send_reschedule(int cpu)
smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE);
}
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+void tick_broadcast(const struct cpumask *mask)
+{
+ smp_cross_call(mask, IPI_TIMER);
+}
+#endif
+
void smp_send_stop(void)
{
unsigned long timeout;
diff --git a/arch/arm64/kernel/suspend.c b/arch/arm64/kernel/suspend.c
new file mode 100644
index 000000000000..1fa9ce4afd8f
--- /dev/null
+++ b/arch/arm64/kernel/suspend.c
@@ -0,0 +1,140 @@
+#include <linux/percpu.h>
+#include <linux/slab.h>
+#include <asm/cacheflush.h>
+#include <asm/cpu_ops.h>
+#include <asm/debug-monitors.h>
+#include <asm/pgtable.h>
+#include <asm/memory.h>
+#include <asm/smp_plat.h>
+#include <asm/suspend.h>
+#include <asm/tlbflush.h>
+
+extern int __cpu_suspend(unsigned long);
+/*
+ * This is called by __cpu_suspend() to save the state, and do whatever
+ * flushing is required to ensure that when the CPU goes to sleep we have
+ * the necessary data available when the caches are not searched.
+ *
+ * @arg: Argument to pass to suspend operations
+ * @ptr: CPU context virtual address
+ * @save_ptr: address of the location where the context physical address
+ * must be saved
+ */
+int __cpu_suspend_finisher(unsigned long arg, struct cpu_suspend_ctx *ptr,
+ phys_addr_t *save_ptr)
+{
+ int cpu = smp_processor_id();
+
+ *save_ptr = virt_to_phys(ptr);
+
+ cpu_do_suspend(ptr);
+ /*
+ * Only flush the context that must be retrieved with the MMU
+ * off. VA primitives ensure the flush is applied to all
+ * cache levels so context is pushed to DRAM.
+ */
+ __flush_dcache_area(ptr, sizeof(*ptr));
+ __flush_dcache_area(save_ptr, sizeof(*save_ptr));
+
+ return cpu_ops[cpu]->cpu_suspend(arg);
+}
+
+/*
+ * This hook is provided so that cpu_suspend code can restore HW
+ * breakpoints as early as possible in the resume path, before reenabling
+ * debug exceptions. Code cannot be run from a CPU PM notifier since by the
+ * time the notifier runs debug exceptions might have been enabled already,
+ * with HW breakpoints registers content still in an unknown state.
+ */
+void (*hw_breakpoint_restore)(void *);
+void __init cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *))
+{
+ /* Prevent multiple restore hook initializations */
+ if (WARN_ON(hw_breakpoint_restore))
+ return;
+ hw_breakpoint_restore = hw_bp_restore;
+}
+
+/**
+ * cpu_suspend
+ *
+ * @arg: argument to pass to the finisher function
+ */
+int cpu_suspend(unsigned long arg)
+{
+ struct mm_struct *mm = current->active_mm;
+ int ret, cpu = smp_processor_id();
+ unsigned long flags;
+
+ /*
+ * If cpu_ops have not been registered or suspend
+ * has not been initialized, cpu_suspend call fails early.
+ */
+ if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_suspend)
+ return -EOPNOTSUPP;
+
+ /*
+ * From this point debug exceptions are disabled to prevent
+ * updates to mdscr register (saved and restored along with
+ * general purpose registers) from kernel debuggers.
+ */
+ local_dbg_save(flags);
+
+ /*
+ * mm context saved on the stack, it will be restored when
+ * the cpu comes out of reset through the identity mapped
+ * page tables, so that the thread address space is properly
+ * set-up on function return.
+ */
+ ret = __cpu_suspend(arg);
+ if (ret == 0) {
+ cpu_switch_mm(mm->pgd, mm);
+ flush_tlb_all();
+
+ /*
+ * Restore per-cpu offset before any kernel
+ * subsystem relying on it has a chance to run.
+ */
+ set_my_cpu_offset(per_cpu_offset(cpu));
+
+ /*
+ * Restore HW breakpoint registers to sane values
+ * before debug exceptions are possibly reenabled
+ * through local_dbg_restore.
+ */
+ if (hw_breakpoint_restore)
+ hw_breakpoint_restore(NULL);
+ }
+
+ /*
+ * Restore pstate flags. OS lock and mdscr have been already
+ * restored, so from this point onwards, debugging is fully
+ * renabled if it was enabled when core started shutdown.
+ */
+ local_dbg_restore(flags);
+
+ return ret;
+}
+
+extern struct sleep_save_sp sleep_save_sp;
+extern phys_addr_t sleep_idmap_phys;
+
+static int cpu_suspend_init(void)
+{
+ void *ctx_ptr;
+
+ /* ctx_ptr is an array of physical addresses */
+ ctx_ptr = kcalloc(mpidr_hash_size(), sizeof(phys_addr_t), GFP_KERNEL);
+
+ if (WARN_ON(!ctx_ptr))
+ return -ENOMEM;
+
+ sleep_save_sp.save_ptr_stash = ctx_ptr;
+ sleep_save_sp.save_ptr_stash_phys = virt_to_phys(ctx_ptr);
+ sleep_idmap_phys = virt_to_phys(idmap_pg_dir);
+ __flush_dcache_area(&sleep_save_sp, sizeof(struct sleep_save_sp));
+ __flush_dcache_area(&sleep_idmap_phys, sizeof(sleep_idmap_phys));
+
+ return 0;
+}
+early_initcall(cpu_suspend_init);
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index b1b31bbc967b..ef355dea3bbf 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -80,6 +80,75 @@ ENTRY(cpu_do_idle)
ret
ENDPROC(cpu_do_idle)
+#ifdef CONFIG_ARM64_CPU_SUSPEND
+/**
+ * cpu_do_suspend - save CPU registers context
+ *
+ * x0: virtual address of context pointer
+ */
+ENTRY(cpu_do_suspend)
+ mrs x2, tpidr_el0
+ mrs x3, tpidrro_el0
+ mrs x4, contextidr_el1
+ mrs x5, mair_el1
+ mrs x6, cpacr_el1
+ mrs x7, ttbr1_el1
+ mrs x8, tcr_el1
+ mrs x9, vbar_el1
+ mrs x10, mdscr_el1
+ mrs x11, oslsr_el1
+ mrs x12, sctlr_el1
+ stp x2, x3, [x0]
+ stp x4, x5, [x0, #16]
+ stp x6, x7, [x0, #32]
+ stp x8, x9, [x0, #48]
+ stp x10, x11, [x0, #64]
+ str x12, [x0, #80]
+ ret
+ENDPROC(cpu_do_suspend)
+
+/**
+ * cpu_do_resume - restore CPU register context
+ *
+ * x0: Physical address of context pointer
+ * x1: ttbr0_el1 to be restored
+ *
+ * Returns:
+ * sctlr_el1 value in x0
+ */
+ENTRY(cpu_do_resume)
+ /*
+ * Invalidate local tlb entries before turning on MMU
+ */
+ tlbi vmalle1
+ ldp x2, x3, [x0]
+ ldp x4, x5, [x0, #16]
+ ldp x6, x7, [x0, #32]
+ ldp x8, x9, [x0, #48]
+ ldp x10, x11, [x0, #64]
+ ldr x12, [x0, #80]
+ msr tpidr_el0, x2
+ msr tpidrro_el0, x3
+ msr contextidr_el1, x4
+ msr mair_el1, x5
+ msr cpacr_el1, x6
+ msr ttbr0_el1, x1
+ msr ttbr1_el1, x7
+ msr tcr_el1, x8
+ msr vbar_el1, x9
+ msr mdscr_el1, x10
+ /*
+ * Restore oslsr_el1 by writing oslar_el1
+ */
+ ubfx x11, x11, #1, #1
+ msr oslar_el1, x11
+ mov x0, x12
+ dsb nsh // Make sure local tlb invalidation completed
+ isb
+ ret
+ENDPROC(cpu_do_resume)
+#endif
+
/*
* cpu_switch_mm(pgd_phys, tsk)
*