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authorLinus Torvalds <torvalds@linux-foundation.org>2013-02-20 14:29:37 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-20 14:29:37 -0800
commit6db167dfc013b0e114c81077ac091ba26a69f4ed (patch)
tree1978b8a2774e0fdb3690065625b0b5eb84475552 /arch/arm/kernel/hw_breakpoint.c
parent32f9aab8ebd886211a7b3e552753af014c3e5225 (diff)
parent9cb543124a2d31af42ce61a4c30765ecc8e5f1fa (diff)
Merge branch 'for-linus-2' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM updates (part two) from Russell King: - breakpoint and perf updates from Will Deacon. - hypervisor boot mode updates from Will. - support for Power State Coordination Interface via the Hypervisor - core ARM support for KVM * 'for-linus-2' of git://git.linaro.org/people/rmk/linux-arm: (32 commits) KVM: ARM: Add maintainer entry for KVM/ARM KVM: ARM: Power State Coordination Interface implementation KVM: ARM: Handle I/O aborts KVM: ARM: Handle guest faults in KVM KVM: ARM: VFP userspace interface KVM: ARM: Demux CCSIDR in the userspace API KVM: ARM: User space API for getting/setting co-proc registers KVM: ARM: Emulation framework and CP15 emulation KVM: ARM: World-switch implementation KVM: ARM: Inject IRQs and FIQs from userspace KVM: ARM: Memory virtualization setup KVM: ARM: Hypervisor initialization KVM: ARM: Initial skeleton to compile KVM support ARM: Section based HYP idmap ARM: Add page table and page defines needed by KVM ARM: perf: simplify __hw_perf_event_init err handling ARM: perf: remove unnecessary checks for idx < 0 ARM: perf: handle armpmu_register failing ARM: perf: don't pretend to support counting of L1I writes ARM: perf: remove redundant NULL check on cpu_pmu ...
Diffstat (limited to 'arch/arm/kernel/hw_breakpoint.c')
-rw-r--r--arch/arm/kernel/hw_breakpoint.c61
1 files changed, 53 insertions, 8 deletions
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index 5ff2e77782b..5eae53e7a2e 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -28,6 +28,7 @@
#include <linux/perf_event.h>
#include <linux/hw_breakpoint.h>
#include <linux/smp.h>
+#include <linux/cpu_pm.h>
#include <asm/cacheflush.h>
#include <asm/cputype.h>
@@ -35,6 +36,7 @@
#include <asm/hw_breakpoint.h>
#include <asm/kdebug.h>
#include <asm/traps.h>
+#include <asm/hardware/coresight.h>
/* Breakpoint currently in use for each BRP. */
static DEFINE_PER_CPU(struct perf_event *, bp_on_reg[ARM_MAX_BRP]);
@@ -49,6 +51,9 @@ static int core_num_wrps;
/* Debug architecture version. */
static u8 debug_arch;
+/* Does debug architecture support OS Save and Restore? */
+static bool has_ossr;
+
/* Maximum supported watchpoint length. */
static u8 max_watchpoint_len;
@@ -903,6 +908,23 @@ static struct undef_hook debug_reg_hook = {
.fn = debug_reg_trap,
};
+/* Does this core support OS Save and Restore? */
+static bool core_has_os_save_restore(void)
+{
+ u32 oslsr;
+
+ switch (get_debug_arch()) {
+ case ARM_DEBUG_ARCH_V7_1:
+ return true;
+ case ARM_DEBUG_ARCH_V7_ECP14:
+ ARM_DBG_READ(c1, c1, 4, oslsr);
+ if (oslsr & ARM_OSLSR_OSLM0)
+ return true;
+ default:
+ return false;
+ }
+}
+
static void reset_ctrl_regs(void *unused)
{
int i, raw_num_brps, err = 0, cpu = smp_processor_id();
@@ -930,11 +952,7 @@ static void reset_ctrl_regs(void *unused)
if ((val & 0x1) == 0)
err = -EPERM;
- /*
- * Check whether we implement OS save and restore.
- */
- ARM_DBG_READ(c1, c1, 4, val);
- if ((val & 0x9) == 0)
+ if (!has_ossr)
goto clear_vcr;
break;
case ARM_DEBUG_ARCH_V7_1:
@@ -955,9 +973,9 @@ static void reset_ctrl_regs(void *unused)
/*
* Unconditionally clear the OS lock by writing a value
- * other than 0xC5ACCE55 to the access register.
+ * other than CS_LAR_KEY to the access register.
*/
- ARM_DBG_WRITE(c1, c0, 4, 0);
+ ARM_DBG_WRITE(c1, c0, 4, ~CS_LAR_KEY);
isb();
/*
@@ -1015,6 +1033,30 @@ static struct notifier_block __cpuinitdata dbg_reset_nb = {
.notifier_call = dbg_reset_notify,
};
+#ifdef CONFIG_CPU_PM
+static int dbg_cpu_pm_notify(struct notifier_block *self, unsigned long action,
+ void *v)
+{
+ if (action == CPU_PM_EXIT)
+ reset_ctrl_regs(NULL);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata dbg_cpu_pm_nb = {
+ .notifier_call = dbg_cpu_pm_notify,
+};
+
+static void __init pm_init(void)
+{
+ cpu_pm_register_notifier(&dbg_cpu_pm_nb);
+}
+#else
+static inline void pm_init(void)
+{
+}
+#endif
+
static int __init arch_hw_breakpoint_init(void)
{
debug_arch = get_debug_arch();
@@ -1024,6 +1066,8 @@ static int __init arch_hw_breakpoint_init(void)
return 0;
}
+ has_ossr = core_has_os_save_restore();
+
/* Determine how many BRPs/WRPs are available. */
core_num_brps = get_num_brps();
core_num_wrps = get_num_wrps();
@@ -1062,8 +1106,9 @@ static int __init arch_hw_breakpoint_init(void)
hook_ifault_code(FAULT_CODE_DEBUG, hw_breakpoint_pending, SIGTRAP,
TRAP_HWBKPT, "breakpoint debug exception");
- /* Register hotplug notifier. */
+ /* Register hotplug and PM notifiers. */
register_cpu_notifier(&dbg_reset_nb);
+ pm_init();
return 0;
}
arch_initcall(arch_hw_breakpoint_init);