From d6a61bfc06d6f2248f3e75f208d64e794082013c Mon Sep 17 00:00:00 2001 From: Luis Machado Date: Thu, 24 Jul 2008 02:10:41 +1000 Subject: powerpc: BookE hardware watchpoint support This patch implements support for HW based watchpoint via the DBSR_DAC (Data Address Compare) facility of the BookE processors. It does so by interfacing with the existing DABR breakpoint code and adding the necessary bits and pieces for the new bits to be properly set or cleared Signed-off-by: Luis Machado Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/signal.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/kernel/signal.c') diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index ad55488939c..7aada783ec6 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -145,8 +145,12 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs) * user space. The DABR will have been cleared if it * triggered inside the kernel. */ - if (current->thread.dabr) + if (current->thread.dabr) { set_dabr(current->thread.dabr); +#if defined(CONFIG_44x) || defined(CONFIG_BOOKE) + mtspr(SPRN_DBCR0, current->thread.dbcr0); +#endif + } if (is32) { if (ka.sa.sa_flags & SA_SIGINFO) -- cgit v1.2.3-70-g09d2 From 2325f0a0c3d76bb515f3312ab2b16afdbffcc594 Mon Sep 17 00:00:00 2001 From: Kumar Gala Date: Sat, 26 Jul 2008 05:27:33 +1000 Subject: powerpc/booke: Clean up the hardware watchpoint support * CONFIG_BOOKE is selected by CONFIG_44x so we dont need both * Fixed a few comments * Go back to only using DBCR0_IDM to determine if we are using debug resources. Signed-off-by: Kumar Gala Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/entry_32.S | 6 +++--- arch/powerpc/kernel/process.c | 8 ++++---- arch/powerpc/kernel/ptrace.c | 7 ++++--- arch/powerpc/kernel/signal.c | 2 +- 4 files changed, 12 insertions(+), 11 deletions(-) (limited to 'arch/powerpc/kernel/signal.c') diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 81c8324a4a3..da52269aec1 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -148,7 +148,7 @@ transfer_to_handler: /* Check to see if the dbcr0 register is set up to debug. Use the internal debug mode bit to do this. */ lwz r12,THREAD_DBCR0(r12) - andis. r12,r12,(DBCR0_IDM | DBSR_DAC1R | DBSR_DAC1W)@h + andis. r12,r12,DBCR0_IDM@h beq+ 3f /* From user and task is ptraced - load up global dbcr0 */ li r12,-1 /* clear all pending debug events */ @@ -292,7 +292,7 @@ syscall_exit_cont: /* If the process has its own DBCR0 value, load it up. The internal debug mode bit tells us that dbcr0 should be loaded. */ lwz r0,THREAD+THREAD_DBCR0(r2) - andis. r10,r0,(DBCR0_IDM | DBSR_DAC1R | DBSR_DAC1W)@h + andis. r10,r0,DBCR0_IDM@h bnel- load_dbcr0 #endif #ifdef CONFIG_44x @@ -720,7 +720,7 @@ restore_user: /* Check whether this process has its own DBCR0 value. The internal debug mode bit tells us that dbcr0 should be loaded. */ lwz r0,THREAD+THREAD_DBCR0(r2) - andis. r10,r0,(DBCR0_IDM | DBSR_DAC1R | DBSR_DAC1W)@h + andis. r10,r0,DBCR0_IDM@h bnel- load_dbcr0 #endif diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index db2497ccc11..e030f3bd502 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -254,7 +254,7 @@ void do_dabr(struct pt_regs *regs, unsigned long address, return; /* Clear the DAC and struct entries. One shot trigger */ -#if (defined(CONFIG_44x) || defined(CONFIG_BOOKE)) +#if defined(CONFIG_BOOKE) mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~(DBSR_DAC1R | DBSR_DAC1W | DBCR0_IDM)); #endif @@ -286,7 +286,7 @@ int set_dabr(unsigned long dabr) mtspr(SPRN_DABR, dabr); #endif -#if defined(CONFIG_44x) || defined(CONFIG_BOOKE) +#if defined(CONFIG_BOOKE) mtspr(SPRN_DAC1, dabr); #endif @@ -373,7 +373,7 @@ struct task_struct *__switch_to(struct task_struct *prev, if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr)) set_dabr(new->thread.dabr); -#if defined(CONFIG_44x) || defined(CONFIG_BOOKE) +#if defined(CONFIG_BOOKE) /* If new thread DAC (HW breakpoint) is the same then leave it */ if (new->thread.dabr) set_dabr(new->thread.dabr); @@ -568,7 +568,7 @@ void flush_thread(void) current->thread.dabr = 0; set_dabr(0); -#if defined(CONFIG_44x) || defined(CONFIG_BOOKE) +#if defined(CONFIG_BOOKE) current->thread.dbcr0 &= ~(DBSR_DAC1R | DBSR_DAC1W); #endif } diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index a5d0e78779c..66204cb51a1 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -717,7 +717,7 @@ void user_disable_single_step(struct task_struct *task) struct pt_regs *regs = task->thread.regs; -#if defined(CONFIG_44x) || defined(CONFIG_BOOKE) +#if defined(CONFIG_BOOKE) /* If DAC then do not single step, skip */ if (task->thread.dabr) return; @@ -744,10 +744,11 @@ int ptrace_set_debugreg(struct task_struct *task, unsigned long addr, if (addr > 0) return -EINVAL; + /* The bottom 3 bits in dabr are flags */ if ((data & ~0x7UL) >= TASK_SIZE) return -EIO; -#ifdef CONFIG_PPC64 +#ifndef CONFIG_BOOKE /* For processors using DABR (i.e. 970), the bottom 3 bits are flags. * It was assumed, on previous implementations, that 3 bits were @@ -769,7 +770,7 @@ int ptrace_set_debugreg(struct task_struct *task, unsigned long addr, task->thread.dabr = data; #endif -#if defined(CONFIG_44x) || defined(CONFIG_BOOKE) +#if defined(CONFIG_BOOKE) /* As described above, it was assumed 3 bits were passed with the data * address, but we will assume only the mode bits will be passed diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index 7aada783ec6..2b5eaa6c8f3 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -147,7 +147,7 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs) */ if (current->thread.dabr) { set_dabr(current->thread.dabr); -#if defined(CONFIG_44x) || defined(CONFIG_BOOKE) +#if defined(CONFIG_BOOKE) mtspr(SPRN_DBCR0, current->thread.dbcr0); #endif } -- cgit v1.2.3-70-g09d2 From 6558ba2b5cc3a2f22039db30616fcd07c1b28ac8 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Sun, 27 Jul 2008 16:49:50 +1000 Subject: powerpc: Call tracehook_signal_handler() when setting up signal frames This makes the powerpc signal handling code call tracehook_signal_handler() after a handler is set up. This means that using PTRACE_SINGLESTEP to enter a signal handler will report to ptrace on the first instruction of the handler, instead of the second. This is consistent with what x86 and other machines do, and what users and debuggers want. BenH: Fixed up the test for the trap value. Signed-off-by: Roland McGrath Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/signal.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/kernel/signal.c') diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index 2b5eaa6c8f3..e74aa0ed4e9 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -9,7 +9,7 @@ * this archive for more details. */ -#include +#include #include #include #include @@ -177,6 +177,12 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs) * its frame, and we can clear the TLF_RESTORE_SIGMASK flag. */ current_thread_info()->local_flags &= ~_TLF_RESTORE_SIGMASK; + + /* + * Let tracing know that we've done the handler setup. + */ + tracehook_signal_handler(signr, &info, &ka, regs, + test_thread_flag(TIF_SINGLESTEP)); } return ret; -- cgit v1.2.3-70-g09d2 From 7d6d637dac2050f30a1b57b0a3dc5de4a10616ba Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Sun, 27 Jul 2008 16:52:52 +1000 Subject: powerpc: Add TIF_NOTIFY_RESUME support for tracehook This adds TIF_NOTIFY_RESUME support for powerpc. When set, we call tracehook_notify_resume() on the way to user mode. This overloads do_signal() to do the work, but changes its arguments to it has the TIF_* bits handy in a register and drops the useless first argument that was always zero. Signed-off-by: Roland McGrath Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/entry_32.S | 4 ++-- arch/powerpc/kernel/entry_64.S | 3 +-- arch/powerpc/kernel/signal.c | 13 ++++++++++++- include/asm-powerpc/signal.h | 3 +-- include/asm-powerpc/thread_info.h | 5 ++++- 5 files changed, 20 insertions(+), 8 deletions(-) (limited to 'arch/powerpc/kernel/signal.c') diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index e6fca6a9014..1cbbf703364 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -1060,8 +1060,8 @@ do_user_signal: /* r10 contains MSR_KERNEL here */ SAVE_NVGPRS(r1) rlwinm r3,r3,0,0,30 stw r3,_TRAP(r1) -2: li r3,0 - addi r4,r1,STACK_FRAME_OVERHEAD +2: addi r3,r1,STACK_FRAME_OVERHEAD + mr r4,r9 bl do_signal REST_NVGPRS(r1) b recheck diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 79c089e97ce..2d802e97097 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -643,8 +643,7 @@ user_work: b .ret_from_except_lite 1: bl .save_nvgprs - li r3,0 - addi r4,r1,STACK_FRAME_OVERHEAD + addi r3,r1,STACK_FRAME_OVERHEAD bl .do_signal b .ret_from_except diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index e74aa0ed4e9..a54405ebd7b 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -112,7 +112,7 @@ static void check_syscall_restart(struct pt_regs *regs, struct k_sigaction *ka, } } -int do_signal(sigset_t *oldset, struct pt_regs *regs) +static int do_signal_pending(sigset_t *oldset, struct pt_regs *regs) { siginfo_t info; int signr; @@ -188,6 +188,17 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs) return ret; } +void do_signal(struct pt_regs *regs, unsigned long thread_info_flags) +{ + if (thread_info_flags & _TIF_SIGPENDING) + do_signal_pending(NULL, regs); + + if (thread_info_flags & _TIF_NOTIFY_RESUME) { + clear_thread_flag(TIF_NOTIFY_RESUME); + tracehook_notify_resume(regs); + } +} + long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, unsigned long r5, unsigned long r6, unsigned long r7, unsigned long r8, struct pt_regs *regs) diff --git a/include/asm-powerpc/signal.h b/include/asm-powerpc/signal.h index a8c7babf495..a7360cdd99e 100644 --- a/include/asm-powerpc/signal.h +++ b/include/asm-powerpc/signal.h @@ -122,8 +122,7 @@ typedef struct sigaltstack { #ifdef __KERNEL__ struct pt_regs; -extern int do_signal(sigset_t *oldset, struct pt_regs *regs); -extern int do_signal32(sigset_t *oldset, struct pt_regs *regs); +extern void do_signal(struct pt_regs *regs, unsigned long thread_info_flags); #define ptrace_signal_deliver(regs, cookie) do { } while (0) #endif /* __KERNEL__ */ diff --git a/include/asm-powerpc/thread_info.h b/include/asm-powerpc/thread_info.h index a9db562df69..9665a26a253 100644 --- a/include/asm-powerpc/thread_info.h +++ b/include/asm-powerpc/thread_info.h @@ -108,6 +108,7 @@ static inline struct thread_info *current_thread_info(void) #define TIF_SECCOMP 10 /* secure computing */ #define TIF_RESTOREALL 11 /* Restore all regs (implies NOERROR) */ #define TIF_NOERROR 12 /* Force successful syscall return */ +#define TIF_NOTIFY_RESUME 13 /* callback before returning to user */ #define TIF_FREEZE 14 /* Freezing for suspend */ #define TIF_RUNLATCH 15 /* Is the runlatch enabled? */ #define TIF_ABI_PENDING 16 /* 32/64 bit switch needed */ @@ -125,12 +126,14 @@ static inline struct thread_info *current_thread_info(void) #define _TIF_SECCOMP (1<