diff options
Diffstat (limited to 'arch/arm/kernel/hw_breakpoint.c')
-rw-r--r-- | arch/arm/kernel/hw_breakpoint.c | 54 |
1 files changed, 25 insertions, 29 deletions
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c index 56ed9a62013..c9f3f046757 100644 --- a/arch/arm/kernel/hw_breakpoint.c +++ b/arch/arm/kernel/hw_breakpoint.c @@ -219,23 +219,6 @@ static int get_num_brps(void) return brps; } -int hw_breakpoint_slots(int type) -{ - /* - * We can be called early, so don't rely on - * our static variables being initialised. - */ - switch (type) { - case TYPE_INST: - return get_num_brps(); - case TYPE_DATA: - return get_num_wrps(); - default: - pr_warning("unknown slot type: %d\n", type); - return 0; - } -} - /* * In order to access the breakpoint/watchpoint control registers, * we must be running in debug monitor mode. Unfortunately, we can @@ -256,8 +239,12 @@ static int enable_monitor_mode(void) goto out; } + /* If monitor mode is already enabled, just return. */ + if (dscr & ARM_DSCR_MDBGEN) + goto out; + /* Write to the corresponding DSCR. */ - switch (debug_arch) { + switch (get_debug_arch()) { case ARM_DEBUG_ARCH_V6: case ARM_DEBUG_ARCH_V6_1: ARM_DBG_WRITE(c1, 0, (dscr | ARM_DSCR_MDBGEN)); @@ -272,15 +259,30 @@ static int enable_monitor_mode(void) /* Check that the write made it through. */ ARM_DBG_READ(c1, 0, dscr); - if (WARN_ONCE(!(dscr & ARM_DSCR_MDBGEN), - "failed to enable monitor mode.")) { + if (!(dscr & ARM_DSCR_MDBGEN)) ret = -EPERM; - } out: return ret; } +int hw_breakpoint_slots(int type) +{ + /* + * We can be called early, so don't rely on + * our static variables being initialised. + */ + switch (type) { + case TYPE_INST: + return get_num_brps(); + case TYPE_DATA: + return get_num_wrps(); + default: + pr_warning("unknown slot type: %d\n", type); + return 0; + } +} + /* * Check if 8-bit byte-address select is available. * This clobbers WRP 0. @@ -294,9 +296,6 @@ static u8 get_max_wp_len(void) if (debug_arch < ARM_DEBUG_ARCH_V7_ECP14) goto out; - if (enable_monitor_mode()) - goto out; - memset(&ctrl, 0, sizeof(ctrl)); ctrl.len = ARM_BREAKPOINT_LEN_8; ctrl_reg = encode_ctrl_reg(ctrl); @@ -879,15 +878,13 @@ static struct notifier_block __cpuinitdata dbg_reset_nb = { static int __init arch_hw_breakpoint_init(void) { - int ret = 0; u32 dscr; debug_arch = get_debug_arch(); if (debug_arch > ARM_DEBUG_ARCH_V7_ECP14) { pr_info("debug architecture 0x%x unsupported.\n", debug_arch); - ret = -ENODEV; - goto out; + return 0; } /* Determine how many BRPs/WRPs are available. */ @@ -928,8 +925,7 @@ static int __init arch_hw_breakpoint_init(void) /* Register hotplug notifier. */ register_cpu_notifier(&dbg_reset_nb); -out: - return ret; + return 0; } arch_initcall(arch_hw_breakpoint_init); |