diff options
| -rw-r--r-- | arch/sh/include/asm/hw_breakpoint.h | 22 | ||||
| -rw-r--r-- | arch/sh/include/asm/processor_32.h | 4 | ||||
| -rw-r--r-- | arch/sh/kernel/cpu/sh4a/Makefile | 9 | ||||
| -rw-r--r-- | arch/sh/kernel/cpu/sh4a/ubc.c | 133 | ||||
| -rw-r--r-- | arch/sh/kernel/hw_breakpoint.c | 164 |
5 files changed, 254 insertions, 78 deletions
diff --git a/arch/sh/include/asm/hw_breakpoint.h b/arch/sh/include/asm/hw_breakpoint.h index 0f4a00f6005..7295d629024 100644 --- a/arch/sh/include/asm/hw_breakpoint.h +++ b/arch/sh/include/asm/hw_breakpoint.h @@ -3,7 +3,6 @@ #include <linux/kdebug.h> #include <linux/types.h> -#include <asm/ubc.h> #ifdef __KERNEL__ #define __ARCH_HW_BREAKPOINT_H @@ -11,7 +10,6 @@ struct arch_hw_breakpoint { char *name; /* Contains name of the symbol to set bkpt */ unsigned long address; - unsigned long asid; u16 len; u16 type; }; @@ -27,13 +25,28 @@ enum { SH_BREAKPOINT_LEN_8 = (1 << 14), }; -/* Total number of available UBC channels */ -#define HBP_NUM 1 /* XXX */ +struct sh_ubc { + const char *name; + unsigned int num_events; + unsigned int trap_nr; + void (*enable)(struct arch_hw_breakpoint *, int); + void (*disable)(struct arch_hw_breakpoint *, int); + void (*enable_all)(unsigned long); + void (*disable_all)(void); + unsigned long (*active_mask)(void); + unsigned long (*triggered_mask)(void); + void (*clear_triggered_mask)(unsigned long); + struct clk *clk; /* optional interface clock / MSTP bit */ +}; struct perf_event; struct task_struct; struct pmu; +/* Maximum number of UBC channels */ +#define HBP_NUM 2 + +/* arch/sh/kernel/hw_breakpoint.c */ extern int arch_check_va_in_userspace(unsigned long va, u16 hbp_len); extern int arch_validate_hwbkpt_settings(struct perf_event *bp, struct task_struct *tsk); @@ -46,6 +59,7 @@ void hw_breakpoint_pmu_read(struct perf_event *bp); void hw_breakpoint_pmu_unthrottle(struct perf_event *bp); extern void arch_fill_perf_breakpoint(struct perf_event *bp); +extern int register_sh_ubc(struct sh_ubc *); extern struct pmu perf_ops_bp; diff --git a/arch/sh/include/asm/processor_32.h b/arch/sh/include/asm/processor_32.h index d60b28271a0..259112cecbd 100644 --- a/arch/sh/include/asm/processor_32.h +++ b/arch/sh/include/asm/processor_32.h @@ -14,7 +14,7 @@ #include <asm/page.h> #include <asm/types.h> #include <asm/ptrace.h> -#include <asm/ubc.h> +#include <asm/hw_breakpoint.h> /* * Default implementation of macro that returns current @@ -102,7 +102,7 @@ struct thread_struct { unsigned long pc; /* Save middle states of ptrace breakpoints */ - struct perf_event *ptrace_bps[NR_UBC_CHANNELS]; + struct perf_event *ptrace_bps[HBP_NUM]; /* floating point info */ union sh_fpu_union fpu; diff --git a/arch/sh/kernel/cpu/sh4a/Makefile b/arch/sh/kernel/cpu/sh4a/Makefile index 33bab477d2e..b144e8af89d 100644 --- a/arch/sh/kernel/cpu/sh4a/Makefile +++ b/arch/sh/kernel/cpu/sh4a/Makefile @@ -41,7 +41,8 @@ pinmux-$(CONFIG_CPU_SUBTYPE_SH7757) := pinmux-sh7757.o pinmux-$(CONFIG_CPU_SUBTYPE_SH7785) := pinmux-sh7785.o pinmux-$(CONFIG_CPU_SUBTYPE_SH7786) := pinmux-sh7786.o -obj-y += $(clock-y) -obj-$(CONFIG_SMP) += $(smp-y) -obj-$(CONFIG_GENERIC_GPIO) += $(pinmux-y) -obj-$(CONFIG_PERF_EVENTS) += perf_event.o +obj-y += $(clock-y) +obj-$(CONFIG_SMP) += $(smp-y) +obj-$(CONFIG_GENERIC_GPIO) += $(pinmux-y) +obj-$(CONFIG_PERF_EVENTS) += perf_event.o +obj-$(CONFIG_HAVE_HW_BREAKPOINT) += ubc.o diff --git a/arch/sh/kernel/cpu/sh4a/ubc.c b/arch/sh/kernel/cpu/sh4a/ubc.c new file mode 100644 index 00000000000..efb2745bcb3 --- /dev/null +++ b/arch/sh/kernel/cpu/sh4a/ubc.c @@ -0,0 +1,133 @@ +/* + * arch/sh/kernel/cpu/sh4a/ubc.c + * + * On-chip UBC support for SH-4A CPUs. + * + * Copyright (C) 2009 - 2010 Paul Mundt + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include <linux/init.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <asm/hw_breakpoint.h> + +#define UBC_CBR(idx) (0xff200000 + (0x20 * idx)) +#define UBC_CRR(idx) (0xff200004 + (0x20 * idx)) +#define UBC_CAR(idx) (0xff200008 + (0x20 * idx)) +#define UBC_CAMR(idx) (0xff20000c + (0x20 * idx)) + +#define UBC_CCMFR 0xff200600 +#define UBC_CBCR 0xff200620 + +/* CRR */ +#define UBC_CRR_PCB (1 << 1) +#define UBC_CRR_BIE (1 << 0) + +/* CBR */ +#define UBC_CBR_CE (1 << 0) + +static struct sh_ubc sh4a_ubc; + +static void sh4a_ubc_enable(struct arch_hw_breakpoint *info, int idx) +{ + __raw_writel(UBC_CBR_CE | info->len | info->type, UBC_CBR(idx)); + __raw_writel(info->address, UBC_CAR(idx)); +} + +static void sh4a_ubc_disable(struct arch_hw_breakpoint *info, int idx) +{ + __raw_writel(0, UBC_CBR(idx)); + __raw_writel(0, UBC_CAR(idx)); +} + +static void sh4a_ubc_enable_all(unsigned long mask) +{ + int i; + + for (i = 0; i < sh4a_ubc.num_events; i++) + if (mask & (1 << i)) + __raw_writel(__raw_readl(UBC_CBR(i)) | UBC_CBR_CE, + UBC_CBR(i)); +} + +static void sh4a_ubc_disable_all(void) +{ + int i; + + for (i = 0; i < sh4a_ubc.num_events; i++) + __raw_writel(__raw_readl(UBC_CBR(i)) & ~UBC_CBR_CE, + UBC_CBR(i)); +} + +static unsigned long sh4a_ubc_active_mask(void) +{ + unsigned long active = 0; + int i; + + for (i = 0; i < sh4a_ubc.num_events; i++) + if (__raw_readl(UBC_CBR(i)) & UBC_CBR_CE) + active |= (1 << i); + + return active; +} + +static unsigned long sh4a_ubc_triggered_mask(void) +{ + return __raw_readl(UBC_CCMFR); +} + +static void sh4a_ubc_clear_triggered_mask(unsigned long mask) +{ + __raw_writel(__raw_readl(UBC_CCMFR) & ~mask, UBC_CCMFR); +} + +static struct sh_ubc sh4a_ubc = { + .name = "SH-4A", + .num_events = 2, + .trap_nr = 0x1e0, + .enable = sh4a_ubc_enable, + .disable = sh4a_ubc_disable, + .enable_all = sh4a_ubc_enable_all, + .disable_all = sh4a_ubc_disable_all, + .active_mask = sh4a_ubc_active_mask, + .triggered_mask = sh4a_ubc_triggered_mask, + .clear_triggered_mask = sh4a_ubc_clear_triggered_mask, +}; + +static int __init sh4a_ubc_init(void) +{ + struct clk *ubc_iclk = clk_get(NULL, "ubc0"); + int i; + + /* + * The UBC MSTP bit is optional, as not all platforms will have + * it. Just ignore it if we can't find it. + */ + if (IS_ERR(ubc_iclk)) + ubc_iclk = NULL; + + clk_enable(ubc_iclk); + + __raw_writel(0, UBC_CBCR); + + for (i = 0; i < sh4a_ubc.num_events; i++) { + __raw_writel(0, UBC_CAMR(i)); + __raw_writel(0, UBC_CBR(i)); + + __raw_writel(UBC_CRR_BIE | UBC_CRR_PCB, UBC_CRR(i)); + + /* dummy read for write posting */ + (void)__raw_readl(UBC_CRR(i)); + } + + clk_disable(ubc_iclk); + + sh4a_ubc.clk = ubc_iclk; + + return register_sh_ubc(&sh4a_ubc); +} +arch_initcall(sh4a_ubc_init); diff --git a/arch/sh/kernel/hw_breakpoint.c b/arch/sh/kernel/hw_breakpoint.c index c515a3ecf56..e2f1753d275 100644 --- a/arch/sh/kernel/hw_breakpoint.c +++ b/arch/sh/kernel/hw_breakpoint.c @@ -3,7 +3,7 @@ * * Unified kernel/user-space hardware breakpoint facility for the on-chip UBC. * - * Copyright (C) 2009 Paul Mundt + * Copyright (C) 2009 - 2010 Paul Mundt * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive @@ -18,38 +18,24 @@ #include <linux/kprobes.h> #include <linux/kdebug.h> #include <linux/io.h> +#include <linux/clk.h> #include <asm/hw_breakpoint.h> #include <asm/mmu_context.h> #include <asm/ptrace.h> -struct ubc_context { - unsigned long pc; - unsigned long state; -}; - -/* Per cpu ubc channel state */ -static DEFINE_PER_CPU(struct ubc_context, ubc_ctx[HBP_NUM]); - /* * Stores the breakpoints currently in use on each breakpoint address * register for each cpus */ static DEFINE_PER_CPU(struct perf_event *, bp_per_reg[HBP_NUM]); -static int __init ubc_init(void) -{ - __raw_writel(0, UBC_CAMR0); - __raw_writel(0, UBC_CBR0); - __raw_writel(0, UBC_CBCR); - - __raw_writel(UBC_CRR_BIE | UBC_CRR_PCB, UBC_CRR0); - - /* dummy read for write posting */ - (void)__raw_readl(UBC_CRR0); +/* + * A dummy placeholder for early accesses until the CPUs get a chance to + * register their UBCs later in the boot process. + */ +static struct sh_ubc ubc_dummy = { .num_events = 0 }; - return 0; -} -arch_initcall(ubc_init); +static struct sh_ubc *sh_ubc __read_mostly = &ubc_dummy; /* * Install a perf counter breakpoint. @@ -62,10 +48,9 @@ arch_initcall(ubc_init); int arch_install_hw_breakpoint(struct perf_event *bp) { struct arch_hw_breakpoint *info = counter_arch_bp(bp); - struct ubc_context *ubc_ctx; int i; - for (i = 0; i < HBP_NUM; i++) { + for (i = 0; i < sh_ubc->num_events; i++) { struct perf_event **slot = &__get_cpu_var(bp_per_reg[i]); if (!*slot) { @@ -74,16 +59,11 @@ int arch_install_hw_breakpoint(struct perf_event *bp) } } - if (WARN_ONCE(i == HBP_NUM, "Can't find any breakpoint slot")) + if (WARN_ONCE(i == sh_ubc->num_events, "Can't find any breakpoint slot")) return -EBUSY; - ubc_ctx = &__get_cpu_var(ubc_ctx[i]); - - ubc_ctx->pc = info->address; - ubc_ctx->state = info->len | info->type; - - __raw_writel(UBC_CBR_CE | ubc_ctx->state, UBC_CBR0); - __raw_writel(ubc_ctx->pc, UBC_CAR0); + clk_enable(sh_ubc->clk); + sh_ubc->enable(info, i); return 0; } @@ -100,10 +80,9 @@ int arch_install_hw_breakpoint(struct perf_event *bp) void arch_uninstall_hw_breakpoint(struct perf_event *bp) { struct arch_hw_breakpoint *info = counter_arch_bp(bp); - struct ubc_context *ubc_ctx; int i; - for (i = 0; i < HBP_NUM; i++) { + for (i = 0; i < sh_ubc->num_events; i++) { struct perf_event **slot = &__get_cpu_var(bp_per_reg[i]); if (*slot == bp) { @@ -112,15 +91,11 @@ void arch_uninstall_hw_breakpoint(struct perf_event *bp) } } - if (WARN_ONCE(i == HBP_NUM, "Can't find any breakpoint slot")) + if (WARN_ONCE(i == sh_ubc->num_events, "Can't find any breakpoint slot")) return; - ubc_ctx = &__get_cpu_var(ubc_ctx[i]); - ubc_ctx->pc = 0; - ubc_ctx->state &= ~(info->len | info->type); - - __raw_writel(ubc_ctx->pc, UBC_CBR0); - __raw_writel(ubc_ctx->state, UBC_CAR0); + sh_ubc->disable(info, i); + clk_disable(sh_ubc->clk); } static int get_hbp_len(u16 hbp_len) @@ -182,10 +157,8 @@ static int arch_store_info(struct perf_event *bp) */ if (info->name) info->address = (unsigned long)kallsyms_lookup_name(info->name); - if (info->address) { - info->asid = get_asid(); + if (info->address) return 0; - } return -EINVAL; } @@ -335,7 +308,7 @@ void flush_ptrace_hw_breakpoint(struct task_struct *tsk) int i; struct thread_struct *t = &tsk->thread; - for (i = 0; i < HBP_NUM; i++) { + for (i = 0; i < sh_ubc->num_events; i++) { unregister_hw_breakpoint(t->ptrace_bps[i]); t->ptrace_bps[i] = NULL; } @@ -345,13 +318,32 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args) { int cpu, i, rc = NOTIFY_STOP; struct perf_event *bp; - unsigned long val; + unsigned int cmf, resume_mask; + + /* + * Do an early return if none of the channels triggered. + */ + cmf = sh_ubc->triggered_mask(); + if (unlikely(!cmf)) + return NOTIFY_DONE; + + /* + * By default, resume all of the active channels. + */ + resume_mask = sh_ubc->active_mask(); - val = __raw_readl(UBC_CBR0); - __raw_writel(val & ~UBC_CBR_CE, UBC_CBR0); + /* + * Disable breakpoints during exception handling. + */ + sh_ubc->disable_all(); cpu = get_cpu(); - for (i = 0; i < HBP_NUM; i++) { + for (i = 0; i < sh_ubc->num_events; i++) { + unsigned long event_mask = (1 << i); + + if (likely(!(cmf & event_mask))) + continue; + /* * The counter may be concurrently released but that can only * occur from a call_rcu() path. We can then safely fetch @@ -361,24 +353,52 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args) rcu_read_lock(); bp = per_cpu(bp_per_reg[i], cpu); - if (bp) { + if (bp) rc = NOTIFY_DONE; - } else { + + /* + * Reset the condition match flag to denote completion of + * exception handling. + */ + sh_ubc->clear_triggered_mask(event_mask); + + /* + * bp can be NULL due to concurrent perf counter + * removing. + */ + if (!bp) { rcu_read_unlock(); break; } + /* + * Don't restore the channel if the breakpoint is from + * ptrace, as it always operates in one-shot mode. + */ + if (bp->overflow_handler == ptrace_triggered) + resume_mask &= ~(1 << i); + perf_bp_event(bp, args->regs); + /* Deliver the signal to userspace */ + if (arch_check_va_in_userspace(bp->attr.bp_addr, + bp->attr.bp_len)) { + siginfo_t info; + + info.si_signo = args->signr; + info.si_errno = notifier_to_errno(rc); + info.si_code = TRAP_HWBKPT; + + force_sig_info(args->signr, &info, current); + } + rcu_read_unlock(); } - if (bp && bp->overflow_handler != ptrace_triggered) { - struct arch_hw_breakpoint *info = counter_arch_bp(bp); + if (cmf == 0) + rc = NOTIFY_DONE; - __raw_writel(UBC_CBR_CE | info->len | info->type, UBC_CBR0); - __raw_writel(info->address, UBC_CAR0); - } + sh_ubc->enable_all(resume_mask); put_cpu(); @@ -388,19 +408,9 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args) BUILD_TRAP_HANDLER(breakpoint) { unsigned long ex = lookup_exception_vector(); - siginfo_t info; - int err; TRAP_HANDLER_DECL; - err = notify_die(DIE_BREAKPOINT, "breakpoint", regs, 0, ex, SIGTRAP); - if (err == NOTIFY_STOP) - return; - - /* Deliver the signal to userspace */ - info.si_signo = SIGTRAP; - info.si_errno = 0; - info.si_code = TRAP_HWBKPT; - force_sig_info(SIGTRAP, &info, current); + notify_die(DIE_BREAKPOINT, "breakpoint", regs, 0, ex, SIGTRAP); } /* @@ -417,8 +427,12 @@ int __kprobes hw_breakpoint_exceptions_notify(struct notifier_block *unused, /* * If the breakpoint hasn't been triggered by the UBC, it's * probably from a debugger, so don't do anything more here. + * + * This also permits the UBC interface clock to remain off for + * non-UBC breakpoints, as we don't need to check the triggered + * or active channel masks. */ - if (args->trapnr != 0x1e0) + if (args->trapnr != sh_ubc->trap_nr) return NOTIFY_DONE; return hw_breakpoint_handler(data); @@ -433,3 +447,17 @@ void hw_breakpoint_pmu_unthrottle(struct perf_event *bp) { /* TODO */ } + +int register_sh_ubc(struct sh_ubc *ubc) +{ + /* Bail if it's already assigned */ + if (sh_ubc != &ubc_dummy) + return -EBUSY; + sh_ubc = ubc; + + pr_info("HW Breakpoints: %s UBC support registered\n", ubc->name); + + WARN_ON(ubc->num_events > HBP_NUM); + + return 0; +} |