Commit c71d4aa7 authored by Russell King's avatar Russell King

Merge branch 'hw-breakpoint' of...

Merge branch 'hw-breakpoint' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into devel-stable
parents 667832da f600b9fc
......@@ -146,15 +146,7 @@ static inline void cti_irq_ack(struct cti *cti)
*/
static inline void cti_unlock(struct cti *cti)
{
void __iomem *base = cti->base;
unsigned long val;
val = __raw_readl(base + LOCKSTATUS);
if (val & 1) {
val = LOCKCODE;
__raw_writel(val, base + LOCKACCESS);
}
__raw_writel(LOCKCODE, cti->base + LOCKACCESS);
}
/**
......@@ -166,14 +158,6 @@ static inline void cti_unlock(struct cti *cti)
*/
static inline void cti_lock(struct cti *cti)
{
void __iomem *base = cti->base;
unsigned long val;
val = __raw_readl(base + LOCKSTATUS);
if (!(val & 1)) {
val = ~LOCKCODE;
__raw_writel(val, base + LOCKACCESS);
}
__raw_writel(~LOCKCODE, cti->base + LOCKACCESS);
}
#endif
......@@ -98,12 +98,12 @@ static inline void decode_ctrl_reg(u32 reg,
#define ARM_BASE_WCR 112
/* Accessor macros for the debug registers. */
#define ARM_DBG_READ(M, OP2, VAL) do {\
asm volatile("mrc p14, 0, %0, c0," #M ", " #OP2 : "=r" (VAL));\
#define ARM_DBG_READ(N, M, OP2, VAL) do {\
asm volatile("mrc p14, 0, %0, " #N "," #M ", " #OP2 : "=r" (VAL));\
} while (0)
#define ARM_DBG_WRITE(M, OP2, VAL) do {\
asm volatile("mcr p14, 0, %0, c0," #M ", " #OP2 : : "r" (VAL));\
#define ARM_DBG_WRITE(N, M, OP2, VAL) do {\
asm volatile("mcr p14, 0, %0, " #N "," #M ", " #OP2 : : "r" (VAL));\
} while (0)
struct notifier_block;
......
......@@ -52,14 +52,14 @@ static u8 debug_arch;
/* Maximum supported watchpoint length. */
static u8 max_watchpoint_len;
#define READ_WB_REG_CASE(OP2, M, VAL) \
case ((OP2 << 4) + M): \
ARM_DBG_READ(c ## M, OP2, VAL); \
#define READ_WB_REG_CASE(OP2, M, VAL) \
case ((OP2 << 4) + M): \
ARM_DBG_READ(c0, c ## M, OP2, VAL); \
break
#define WRITE_WB_REG_CASE(OP2, M, VAL) \
case ((OP2 << 4) + M): \
ARM_DBG_WRITE(c ## M, OP2, VAL);\
#define WRITE_WB_REG_CASE(OP2, M, VAL) \
case ((OP2 << 4) + M): \
ARM_DBG_WRITE(c0, c ## M, OP2, VAL); \
break
#define GEN_READ_WB_REG_CASES(OP2, VAL) \
......@@ -136,12 +136,12 @@ static u8 get_debug_arch(void)
/* Do we implement the extended CPUID interface? */
if (((read_cpuid_id() >> 16) & 0xf) != 0xf) {
pr_warning("CPUID feature registers not supported. "
"Assuming v6 debug is present.\n");
pr_warn_once("CPUID feature registers not supported. "
"Assuming v6 debug is present.\n");
return ARM_DEBUG_ARCH_V6;
}
ARM_DBG_READ(c0, 0, didr);
ARM_DBG_READ(c0, c0, 0, didr);
return (didr >> 16) & 0xf;
}
......@@ -169,7 +169,7 @@ static int debug_exception_updates_fsr(void)
static int get_num_wrp_resources(void)
{
u32 didr;
ARM_DBG_READ(c0, 0, didr);
ARM_DBG_READ(c0, c0, 0, didr);
return ((didr >> 28) & 0xf) + 1;
}
......@@ -177,7 +177,7 @@ static int get_num_wrp_resources(void)
static int get_num_brp_resources(void)
{
u32 didr;
ARM_DBG_READ(c0, 0, didr);
ARM_DBG_READ(c0, c0, 0, didr);
return ((didr >> 24) & 0xf) + 1;
}
......@@ -228,19 +228,17 @@ static int get_num_brps(void)
* be put into halting debug mode at any time by an external debugger
* but there is nothing we can do to prevent that.
*/
static int enable_monitor_mode(void)
static int monitor_mode_enabled(void)
{
u32 dscr;
int ret = 0;
ARM_DBG_READ(c1, 0, dscr);
ARM_DBG_READ(c0, c1, 0, dscr);
return !!(dscr & ARM_DSCR_MDBGEN);
}
/* Ensure that halting mode is disabled. */
if (WARN_ONCE(dscr & ARM_DSCR_HDBGEN,
"halting debug mode enabled. Unable to access hardware resources.\n")) {
ret = -EPERM;
goto out;
}
static int enable_monitor_mode(void)
{
u32 dscr;
ARM_DBG_READ(c0, c1, 0, dscr);
/* If monitor mode is already enabled, just return. */
if (dscr & ARM_DSCR_MDBGEN)
......@@ -250,24 +248,27 @@ static int enable_monitor_mode(void)
switch (get_debug_arch()) {
case ARM_DEBUG_ARCH_V6:
case ARM_DEBUG_ARCH_V6_1:
ARM_DBG_WRITE(c1, 0, (dscr | ARM_DSCR_MDBGEN));
ARM_DBG_WRITE(c0, c1, 0, (dscr | ARM_DSCR_MDBGEN));
break;
case ARM_DEBUG_ARCH_V7_ECP14:
case ARM_DEBUG_ARCH_V7_1:
ARM_DBG_WRITE(c2, 2, (dscr | ARM_DSCR_MDBGEN));
ARM_DBG_WRITE(c0, c2, 2, (dscr | ARM_DSCR_MDBGEN));
isb();
break;
default:
ret = -ENODEV;
goto out;
return -ENODEV;
}
/* Check that the write made it through. */
ARM_DBG_READ(c1, 0, dscr);
if (!(dscr & ARM_DSCR_MDBGEN))
ret = -EPERM;
ARM_DBG_READ(c0, c1, 0, dscr);
if (!(dscr & ARM_DSCR_MDBGEN)) {
pr_warn_once("Failed to enable monitor mode on CPU %d.\n",
smp_processor_id());
return -EPERM;
}
out:
return ret;
return 0;
}
int hw_breakpoint_slots(int type)
......@@ -328,14 +329,9 @@ 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, ctrl_base, val_base, ret = 0;
int i, max_slots, ctrl_base, val_base;
u32 addr, ctrl;
/* Ensure that we are in monitor mode and halting mode is disabled. */
ret = enable_monitor_mode();
if (ret)
goto out;
addr = info->address;
ctrl = encode_ctrl_reg(info->ctrl) | 0x1;
......@@ -362,9 +358,9 @@ int arch_install_hw_breakpoint(struct perf_event *bp)
}
}
if (WARN_ONCE(i == max_slots, "Can't find any breakpoint slot\n")) {
ret = -EBUSY;
goto out;
if (i == max_slots) {
pr_warning("Can't find any breakpoint slot\n");
return -EBUSY;
}
/* Override the breakpoint data with the step data. */
......@@ -383,9 +379,7 @@ int arch_install_hw_breakpoint(struct perf_event *bp)
/* Setup the control register. */
write_wb_reg(ctrl_base + i, ctrl);
out:
return ret;
return 0;
}
void arch_uninstall_hw_breakpoint(struct perf_event *bp)
......@@ -416,8 +410,10 @@ void arch_uninstall_hw_breakpoint(struct perf_event *bp)
}
}
if (WARN_ONCE(i == max_slots, "Can't find any breakpoint slot\n"))
if (i == max_slots) {
pr_warning("Can't find any breakpoint slot\n");
return;
}
/* Ensure that we disable the mismatch breakpoint. */
if (info->ctrl.type != ARM_BREAKPOINT_EXECUTE &&
......@@ -596,6 +592,10 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
int ret = 0;
u32 offset, alignment_mask = 0x3;
/* Ensure that we are in monitor debug mode. */
if (!monitor_mode_enabled())
return -ENODEV;
/* Build the arch_hw_breakpoint. */
ret = arch_build_bp_info(bp);
if (ret)
......@@ -858,7 +858,7 @@ static int hw_breakpoint_pending(unsigned long addr, unsigned int fsr,
local_irq_enable();
/* We only handle watchpoints and hardware breakpoints. */
ARM_DBG_READ(c1, 0, dscr);
ARM_DBG_READ(c0, c1, 0, dscr);
/* Perform perf callbacks. */
switch (ARM_DSCR_MOE(dscr)) {
......@@ -906,7 +906,7 @@ static struct undef_hook debug_reg_hook = {
static void reset_ctrl_regs(void *unused)
{
int i, raw_num_brps, err = 0, cpu = smp_processor_id();
u32 dbg_power;
u32 val;
/*
* v7 debug contains save and restore registers so that debug state
......@@ -919,23 +919,30 @@ static void reset_ctrl_regs(void *unused)
switch (debug_arch) {
case ARM_DEBUG_ARCH_V6:
case ARM_DEBUG_ARCH_V6_1:
/* ARMv6 cores just need to reset the registers. */
goto reset_regs;
/* ARMv6 cores clear the registers out of reset. */
goto out_mdbgen;
case ARM_DEBUG_ARCH_V7_ECP14:
/*
* Ensure sticky power-down is clear (i.e. debug logic is
* powered up).
*/
asm volatile("mrc p14, 0, %0, c1, c5, 4" : "=r" (dbg_power));
if ((dbg_power & 0x1) == 0)
ARM_DBG_READ(c1, c5, 4, val);
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)
goto clear_vcr;
break;
case ARM_DEBUG_ARCH_V7_1:
/*
* Ensure the OS double lock is clear.
*/
asm volatile("mrc p14, 0, %0, c1, c3, 4" : "=r" (dbg_power));
if ((dbg_power & 0x1) == 1)
ARM_DBG_READ(c1, c3, 4, val);
if ((val & 0x1) == 1)
err = -EPERM;
break;
}
......@@ -947,24 +954,29 @@ static void reset_ctrl_regs(void *unused)
}
/*
* Unconditionally clear the lock by writing a value
* Unconditionally clear the OS lock by writing a value
* other than 0xC5ACCE55 to the access register.
*/
asm volatile("mcr p14, 0, %0, c1, c0, 4" : : "r" (0));
ARM_DBG_WRITE(c1, c0, 4, 0);
isb();
/*
* Clear any configured vector-catch events before
* enabling monitor mode.
*/
asm volatile("mcr p14, 0, %0, c0, c7, 0" : : "r" (0));
clear_vcr:
ARM_DBG_WRITE(c0, c7, 0, 0);
isb();
reset_regs:
if (enable_monitor_mode())
if (cpumask_intersects(&debug_err_mask, cpumask_of(cpu))) {
pr_warning("CPU %d failed to disable vector catch\n", cpu);
return;
}
/* We must also reset any reserved registers. */
/*
* The control/value register pairs are UNKNOWN out of reset so
* clear them to avoid spurious debug events.
*/
raw_num_brps = get_num_brp_resources();
for (i = 0; i < raw_num_brps; ++i) {
write_wb_reg(ARM_BASE_BCR + i, 0UL);
......@@ -975,6 +987,19 @@ static void reset_ctrl_regs(void *unused)
write_wb_reg(ARM_BASE_WCR + i, 0UL);
write_wb_reg(ARM_BASE_WVR + i, 0UL);
}
if (cpumask_intersects(&debug_err_mask, cpumask_of(cpu))) {
pr_warning("CPU %d failed to clear debug register pairs\n", cpu);
return;
}
/*
* Have a crack at enabling monitor mode. We don't actually need
* it yet, but reporting an error early is useful if it fails.
*/
out_mdbgen:
if (enable_monitor_mode())
cpumask_or(&debug_err_mask, &debug_err_mask, cpumask_of(cpu));
}
static int __cpuinit dbg_reset_notify(struct notifier_block *self,
......@@ -992,8 +1017,6 @@ static struct notifier_block __cpuinitdata dbg_reset_nb = {
static int __init arch_hw_breakpoint_init(void)
{
u32 dscr;
debug_arch = get_debug_arch();
if (!debug_arch_supported()) {
......@@ -1028,17 +1051,10 @@ static int __init arch_hw_breakpoint_init(void)
core_num_brps, core_has_mismatch_brps() ? "(+1 reserved) " :
"", core_num_wrps);
ARM_DBG_READ(c1, 0, dscr);
if (dscr & ARM_DSCR_HDBGEN) {
max_watchpoint_len = 4;
pr_warning("halting debug mode enabled. Assuming maximum watchpoint size of %u bytes.\n",
max_watchpoint_len);
} else {
/* Work out the maximum supported watchpoint length. */
max_watchpoint_len = get_max_wp_len();
pr_info("maximum watchpoint size is %u bytes.\n",
max_watchpoint_len);
}
/* Work out the maximum supported watchpoint length. */
max_watchpoint_len = get_max_wp_len();
pr_info("maximum watchpoint size is %u bytes.\n",
max_watchpoint_len);
/* Register debug fault handler. */
hook_fault_code(FAULT_CODE_DEBUG, hw_breakpoint_pending, SIGTRAP,
......
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