diff options
Diffstat (limited to 'arch/arm/kernel/hw_breakpoint.c')
| -rw-r--r-- | arch/arm/kernel/hw_breakpoint.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c index d600bd35070..44b84fe6e1b 100644 --- a/arch/arm/kernel/hw_breakpoint.c +++ b/arch/arm/kernel/hw_breakpoint.c @@ -836,9 +836,11 @@ static int hw_breakpoint_pending(unsigned long addr, unsigned int fsr, /* * One-time initialisation. */ -static void reset_ctrl_regs(void *unused) +static void reset_ctrl_regs(void *info) { - int i; + int i, cpu = smp_processor_id(); + u32 dbg_power; + cpumask_t *cpumask = info; /* * v7 debug contains save and restore registers so that debug state @@ -850,6 +852,17 @@ static void reset_ctrl_regs(void *unused) */ if (debug_arch >= 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) { + pr_warning("CPU %d debug is powered down!\n", cpu); + cpumask_or(cpumask, cpumask, cpumask_of(cpu)); + return; + } + + /* * Unconditionally clear the lock by writing a value * other than 0xC5ACCE55 to the access register. */ @@ -887,6 +900,7 @@ static struct notifier_block __cpuinitdata dbg_reset_nb = { static int __init arch_hw_breakpoint_init(void) { u32 dscr; + cpumask_t cpumask = { CPU_BITS_NONE }; debug_arch = get_debug_arch(); @@ -911,7 +925,13 @@ 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. */ - on_each_cpu(reset_ctrl_regs, NULL, 1); + on_each_cpu(reset_ctrl_regs, &cpumask, 1); + if (!cpumask_empty(&cpumask)) { + core_num_brps = 0; + core_num_reserved_brps = 0; + core_num_wrps = 0; + return 0; + } ARM_DBG_READ(c1, 0, dscr); if (dscr & ARM_DSCR_HDBGEN) { |