diff options
Diffstat (limited to 'arch/xtensa')
33 files changed, 2593 insertions, 78 deletions
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index 7e9464b0fc00..e832d3e9835e 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -17,6 +17,7 @@ config XTENSA select HAVE_DMA_API_DEBUG select HAVE_FUNCTION_TRACER select HAVE_FUTEX_CMPXCHG if !MMU + select HAVE_HW_BREAKPOINT if PERF_EVENTS select HAVE_IRQ_TIME_ACCOUNTING select HAVE_OPROFILE select HAVE_PERF_EVENTS @@ -138,6 +139,22 @@ config XTENSA_VARIANT_HAVE_PERF_EVENTS If unsure, say N. +config XTENSA_FAKE_NMI + bool "Treat PMM IRQ as NMI" + depends on XTENSA_VARIANT_HAVE_PERF_EVENTS + default n + help + If PMM IRQ is the only IRQ at EXCM level it is safe to + treat it as NMI, which improves accuracy of profiling. + + If there are other interrupts at or above PMM IRQ priority level + but not above the EXCM level, PMM IRQ still may be treated as NMI, + but only if these IRQs are not used. There will be a build warning + saying that this is not safe, and a bugcheck if one of these IRQs + actually fire. + + If unsure, say N. + config XTENSA_UNALIGNED_USER bool "Unaligned memory access in use space" help diff --git a/arch/xtensa/Makefile b/arch/xtensa/Makefile index 709b5748a2d7..e54189427b31 100644 --- a/arch/xtensa/Makefile +++ b/arch/xtensa/Makefile @@ -53,9 +53,11 @@ endif ifeq ($(shell echo __XTENSA_EB__ | $(CC) -E - | grep -v "\#"),1) CHECKFLAGS += -D__XTENSA_EB__ +KBUILD_CPPFLAGS += -DCONFIG_CPU_BIG_ENDIAN endif ifeq ($(shell echo __XTENSA_EL__ | $(CC) -E - | grep -v "\#"),1) CHECKFLAGS += -D__XTENSA_EL__ +KBUILD_CPPFLAGS += -DCONFIG_CPU_LITTLE_ENDIAN endif vardirs := $(patsubst %,arch/xtensa/variants/%/,$(variant-y)) diff --git a/arch/xtensa/boot/dts/kc705.dts b/arch/xtensa/boot/dts/kc705.dts index c4d17a34ab86..b1f4ee8c9a22 100644 --- a/arch/xtensa/boot/dts/kc705.dts +++ b/arch/xtensa/boot/dts/kc705.dts @@ -5,7 +5,7 @@ / { compatible = "cdns,xtensa-kc705"; chosen { - bootargs = "earlycon=uart8250,mmio32,0xfd050020,115200n8 console=ttyS0,115200n8 ip=dhcp root=/dev/nfs rw debug memmap=0x38000000"; + bootargs = "earlycon=uart8250,mmio32native,0xfd050020,115200n8 console=ttyS0,115200n8 ip=dhcp root=/dev/nfs rw debug memmap=0x38000000"; }; memory@0 { device_type = "memory"; diff --git a/arch/xtensa/boot/dts/xtfpga.dtsi b/arch/xtensa/boot/dts/xtfpga.dtsi index cd0b9e34adc8..cd45f9c2c448 100644 --- a/arch/xtensa/boot/dts/xtfpga.dtsi +++ b/arch/xtensa/boot/dts/xtfpga.dtsi @@ -5,7 +5,7 @@ interrupt-parent = <&pic>; chosen { - bootargs = "earlycon=uart8250,mmio32,0xfd050020,115200n8 console=ttyS0,115200n8 ip=dhcp root=/dev/nfs rw debug"; + bootargs = "earlycon=uart8250,mmio32native,0xfd050020,115200n8 console=ttyS0,115200n8 ip=dhcp root=/dev/nfs rw debug"; }; memory@0 { @@ -60,6 +60,8 @@ no-loopback-test; reg = <0x0d050020 0x20>; reg-shift = <2>; + reg-io-width = <4>; + native-endian; interrupts = <0 1>; /* external irq 0 */ clocks = <&osc>; }; @@ -67,6 +69,7 @@ enet0: ethoc@0d030000 { compatible = "opencores,ethoc"; reg = <0x0d030000 0x4000 0x0d800000 0x4000>; + native-endian; interrupts = <1 1>; /* external irq 1 */ local-mac-address = [00 50 c2 13 6f 00]; clocks = <&osc>; @@ -86,7 +89,8 @@ #size-cells = <0>; reg = <0x0d090000 0x20>; reg-shift = <2>; - reg-io-width = <1>; + reg-io-width = <4>; + native-endian; interrupts = <4 1>; clocks = <&osc>; diff --git a/arch/xtensa/include/asm/hw_breakpoint.h b/arch/xtensa/include/asm/hw_breakpoint.h new file mode 100644 index 000000000000..dbe3053b284a --- /dev/null +++ b/arch/xtensa/include/asm/hw_breakpoint.h @@ -0,0 +1,58 @@ +/* + * Xtensa hardware breakpoints/watchpoints handling functions + * + * 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. + * + * Copyright (C) 2016 Cadence Design Systems Inc. + */ + +#ifndef __ASM_XTENSA_HW_BREAKPOINT_H +#define __ASM_XTENSA_HW_BREAKPOINT_H + +#ifdef CONFIG_HAVE_HW_BREAKPOINT + +#include <linux/kdebug.h> +#include <linux/types.h> +#include <uapi/linux/hw_breakpoint.h> + +/* Breakpoint */ +#define XTENSA_BREAKPOINT_EXECUTE 0 + +/* Watchpoints */ +#define XTENSA_BREAKPOINT_LOAD 1 +#define XTENSA_BREAKPOINT_STORE 2 + +struct arch_hw_breakpoint { + unsigned long address; + u16 len; + u16 type; +}; + +struct perf_event; +struct pt_regs; +struct task_struct; + +int hw_breakpoint_slots(int type); +int arch_check_bp_in_kernelspace(struct perf_event *bp); +int arch_validate_hwbkpt_settings(struct perf_event *bp); +int hw_breakpoint_exceptions_notify(struct notifier_block *unused, + unsigned long val, void *data); + +int arch_install_hw_breakpoint(struct perf_event *bp); +void arch_uninstall_hw_breakpoint(struct perf_event *bp); +void hw_breakpoint_pmu_read(struct perf_event *bp); +int check_hw_breakpoint(struct pt_regs *regs); +void clear_ptrace_hw_breakpoint(struct task_struct *tsk); + +#else + +struct task_struct; + +static inline void clear_ptrace_hw_breakpoint(struct task_struct *tsk) +{ +} + +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ +#endif /* __ASM_XTENSA_HW_BREAKPOINT_H */ diff --git a/arch/xtensa/include/asm/io.h b/arch/xtensa/include/asm/io.h index 74fed0b4e2c2..c38e5a732d86 100644 --- a/arch/xtensa/include/asm/io.h +++ b/arch/xtensa/include/asm/io.h @@ -25,9 +25,12 @@ #ifdef CONFIG_MMU +void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size); +void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size); +void xtensa_iounmap(volatile void __iomem *addr); + /* * Return the virtual address for the specified bus memory. - * Note that we currently don't support any address outside the KIO segment. */ static inline void __iomem *ioremap_nocache(unsigned long offset, unsigned long size) @@ -36,7 +39,7 @@ static inline void __iomem *ioremap_nocache(unsigned long offset, && offset - XCHAL_KIO_PADDR < XCHAL_KIO_SIZE) return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_BYPASS_VADDR); else - BUG(); + return xtensa_ioremap_nocache(offset, size); } static inline void __iomem *ioremap_cache(unsigned long offset, @@ -46,7 +49,7 @@ static inline void __iomem *ioremap_cache(unsigned long offset, && offset - XCHAL_KIO_PADDR < XCHAL_KIO_SIZE) return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_CACHED_VADDR); else - BUG(); + return xtensa_ioremap_cache(offset, size); } #define ioremap_cache ioremap_cache @@ -60,6 +63,13 @@ static inline void __iomem *ioremap(unsigned long offset, unsigned long size) static inline void iounmap(volatile void __iomem *addr) { + unsigned long va = (unsigned long) addr; + + if (!(va >= XCHAL_KIO_CACHED_VADDR && + va - XCHAL_KIO_CACHED_VADDR < XCHAL_KIO_SIZE) && + !(va >= XCHAL_KIO_BYPASS_VADDR && + va - XCHAL_KIO_BYPASS_VADDR < XCHAL_KIO_SIZE)) + xtensa_iounmap(addr); } #define virt_to_bus virt_to_phys diff --git a/arch/xtensa/include/asm/irqflags.h b/arch/xtensa/include/asm/irqflags.h index 8e090c709046..407606e576f8 100644 --- a/arch/xtensa/include/asm/irqflags.h +++ b/arch/xtensa/include/asm/irqflags.h @@ -13,6 +13,7 @@ #define _XTENSA_IRQFLAGS_H #include <linux/types.h> +#include <asm/processor.h> static inline unsigned long arch_local_save_flags(void) { diff --git a/arch/xtensa/include/asm/processor.h b/arch/xtensa/include/asm/processor.h index 83e2e4bc01ba..d2e40d39c615 100644 --- a/arch/xtensa/include/asm/processor.h +++ b/arch/xtensa/include/asm/processor.h @@ -78,22 +78,20 @@ #define XTENSA_INTLEVEL_MASK(level) _XTENSA_INTLEVEL_MASK(level) #define _XTENSA_INTLEVEL_MASK(level) (XCHAL_INTLEVEL##level##_MASK) -#define IS_POW2(v) (((v) & ((v) - 1)) == 0) +#define XTENSA_INTLEVEL_ANDBELOW_MASK(l) _XTENSA_INTLEVEL_ANDBELOW_MASK(l) +#define _XTENSA_INTLEVEL_ANDBELOW_MASK(l) (XCHAL_INTLEVEL##l##_ANDBELOW_MASK) #define PROFILING_INTLEVEL XTENSA_INT_LEVEL(XCHAL_PROFILING_INTERRUPT) /* LOCKLEVEL defines the interrupt level that masks all * general-purpose interrupts. */ -#if defined(CONFIG_XTENSA_VARIANT_HAVE_PERF_EVENTS) && \ - defined(XCHAL_PROFILING_INTERRUPT) && \ - PROFILING_INTLEVEL == XCHAL_EXCM_LEVEL && \ - XCHAL_EXCM_LEVEL > 1 && \ - IS_POW2(XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL)) -#define LOCKLEVEL (XCHAL_EXCM_LEVEL - 1) +#if defined(CONFIG_XTENSA_FAKE_NMI) && defined(XCHAL_PROFILING_INTERRUPT) +#define LOCKLEVEL (PROFILING_INTLEVEL - 1) #else #define LOCKLEVEL XCHAL_EXCM_LEVEL #endif + #define TOPLEVEL XCHAL_EXCM_LEVEL #define XTENSA_FAKE_NMI (LOCKLEVEL < TOPLEVEL) @@ -132,11 +130,10 @@ struct thread_struct { unsigned long bad_vaddr; /* last user fault */ unsigned long bad_uaddr; /* last kernel fault accessing user space */ unsigned long error_code; - - unsigned long ibreak[XCHAL_NUM_IBREAK]; - unsigned long dbreaka[XCHAL_NUM_DBREAK]; - unsigned long dbreakc[XCHAL_NUM_DBREAK]; - +#ifdef CONFIG_HAVE_HW_BREAKPOINT + struct perf_event *ptrace_bp[XCHAL_NUM_IBREAK]; + struct perf_event *ptrace_wp[XCHAL_NUM_DBREAK]; +#endif /* Make structure 16 bytes aligned. */ int align[0] __attribute__ ((aligned(16))); }; diff --git a/arch/xtensa/include/asm/regs.h b/arch/xtensa/include/asm/regs.h index 4ba9f516b0e2..881a1134a4b4 100644 --- a/arch/xtensa/include/asm/regs.h +++ b/arch/xtensa/include/asm/regs.h @@ -28,6 +28,7 @@ /* Special registers. */ #define SREG_MR 32 +#define SREG_IBREAKENABLE 96 #define SREG_IBREAKA 128 #define SREG_DBREAKA 144 #define SREG_DBREAKC 160 @@ -103,6 +104,8 @@ /* DEBUGCAUSE register fields. */ +#define DEBUGCAUSE_DBNUM_MASK 0xf00 +#define DEBUGCAUSE_DBNUM_SHIFT 8 /* First bit of DBNUM field */ #define DEBUGCAUSE_DEBUGINT_BIT 5 /* External debug interrupt */ #define DEBUGCAUSE_BREAKN_BIT 4 /* BREAK.N instruction */ #define DEBUGCAUSE_BREAK_BIT 3 /* BREAK instruction */ diff --git a/arch/xtensa/include/asm/thread_info.h b/arch/xtensa/include/asm/thread_info.h index 9ad12c617184..7be2400f745a 100644 --- a/arch/xtensa/include/asm/thread_info.h +++ b/arch/xtensa/include/asm/thread_info.h @@ -111,6 +111,7 @@ static inline struct thread_info *current_thread_info(void) #define TIF_MEMDIE 5 /* is terminating due to OOM killer */ #define TIF_RESTORE_SIGMASK 6 /* restore signal mask in do_signal() */ #define TIF_NOTIFY_RESUME 7 /* callback before returning to user */ +#define TIF_DB_DISABLED 8 /* debug trap disabled for syscall */ #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) #define _TIF_SIGPENDING (1<<TIF_SIGPENDING) diff --git a/arch/xtensa/include/asm/timex.h b/arch/xtensa/include/asm/timex.h index ca929e6a38b5..f9b389d4e973 100644 --- a/arch/xtensa/include/asm/timex.h +++ b/arch/xtensa/include/asm/timex.h @@ -12,19 +12,16 @@ #include <asm/processor.h> #include <linux/stringify.h> -#define _INTLEVEL(x) XCHAL_INT ## x ## _LEVEL -#define INTLEVEL(x) _INTLEVEL(x) - #if XCHAL_NUM_TIMERS > 0 && \ - INTLEVEL(XCHAL_TIMER0_INTERRUPT) <= XCHAL_EXCM_LEVEL + XTENSA_INT_LEVEL(XCHAL_TIMER0_INTERRUPT) <= XCHAL_EXCM_LEVEL # define LINUX_TIMER 0 # define LINUX_TIMER_INT XCHAL_TIMER0_INTERRUPT #elif XCHAL_NUM_TIMERS > 1 && \ - INTLEVEL(XCHAL_TIMER1_INTERRUPT) <= XCHAL_EXCM_LEVEL + XTENSA_INT_LEVEL(XCHAL_TIMER1_INTERRUPT) <= XCHAL_EXCM_LEVEL # define LINUX_TIMER 1 # define LINUX_TIMER_INT XCHAL_TIMER1_INTERRUPT #elif XCHAL_NUM_TIMERS > 2 && \ - INTLEVEL(XCHAL_TIMER2_INTERRUPT) <= XCHAL_EXCM_LEVEL + XTENSA_INT_LEVEL(XCHAL_TIMER2_INTERRUPT) <= XCHAL_EXCM_LEVEL # define LINUX_TIMER 2 # define LINUX_TIMER_INT XCHAL_TIMER2_INTERRUPT #else diff --git a/arch/xtensa/include/asm/traps.h b/arch/xtensa/include/asm/traps.h index 28f33a8b7f5f..2e69aa4b843f 100644 --- a/arch/xtensa/include/asm/traps.h +++ b/arch/xtensa/include/asm/traps.h @@ -65,4 +65,21 @@ static inline void spill_registers(void) #endif } +struct debug_table { + /* Pointer to debug exception handler */ + void (*debug_exception)(void); + /* Temporary register save area */ + unsigned long debug_save[1]; +#ifdef CONFIG_HAVE_HW_BREAKPOINT + /* Save area for DBREAKC registers */ + unsigned long dbreakc_save[XCHAL_NUM_DBREAK]; + /* Saved ICOUNT register */ + unsigned long icount_save; + /* Saved ICOUNTLEVEL register */ + unsigned long icount_level_save; +#endif +}; + +void debug_exception(void); + #endif /* _XTENSA_TRAPS_H */ diff --git a/arch/xtensa/include/uapi/asm/ptrace.h b/arch/xtensa/include/uapi/asm/ptrace.h index ee17aa842fdf..6ccbd9e38e35 100644 --- a/arch/xtensa/include/uapi/asm/ptrace.h +++ b/arch/xtensa/include/uapi/asm/ptrace.h @@ -72,6 +72,8 @@ #define PTRACE_SETREGS 13 #define PTRACE_GETXTREGS 18 #define PTRACE_SETXTREGS 19 +#define PTRACE_GETHBPREGS 20 +#define PTRACE_SETHBPREGS 21 #endif /* _UAPI_XTENSA_PTRACE_H */ diff --git a/arch/xtensa/kernel/Makefile b/arch/xtensa/kernel/Makefile index 4db730290d2d..c31f5d5afc7d 100644 --- a/arch/xtensa/kernel/Makefile +++ b/arch/xtensa/kernel/Makefile @@ -8,12 +8,12 @@ obj-y := align.o coprocessor.o entry.o irq.o pci-dma.o platform.o process.o \ ptrace.o setup.o signal.o stacktrace.o syscall.o time.o traps.o \ vectors.o -obj-$(CONFIG_KGDB) += xtensa-stub.o obj-$(CONFIG_PCI) += pci.o obj-$(CONFIG_MODULES) += xtensa_ksyms.o module.o obj-$(CONFIG_FUNCTION_TRACER) += mcount.o obj-$(CONFIG_SMP) += smp.o mxhead.o obj-$(CONFIG_XTENSA_VARIANT_HAVE_PERF_EVENTS) += perf_event.o +obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o AFLAGS_head.o += -mtext-section-literals AFLAGS_mxhead.o += -mtext-section-literals diff --git a/arch/xtensa/kernel/asm-offsets.c b/arch/xtensa/kernel/asm-offsets.c index b123ace3b67c..8e10e357ee32 100644 --- a/arch/xtensa/kernel/asm-offsets.c +++ b/arch/xtensa/kernel/asm-offsets.c @@ -23,6 +23,7 @@ #include <linux/kbuild.h> #include <asm/ptrace.h> +#include <asm/traps.h> #include <asm/uaccess.h> int main(void) @@ -117,5 +118,16 @@ int main(void) DEFINE(_CLONE_UNTRACED, CLONE_UNTRACED); DEFINE(PG_ARCH_1, PG_arch_1); + /* struct debug_table */ + DEFINE(DT_DEBUG_EXCEPTION, + offsetof(struct debug_table, debug_exception)); + DEFINE(DT_DEBUG_SAVE, offsetof(struct debug_table, debug_save)); +#ifdef CONFIG_HAVE_HW_BREAKPOINT + DEFINE(DT_DBREAKC_SAVE, offsetof(struct debug_table, dbreakc_save)); + DEFINE(DT_ICOUNT_SAVE, offsetof(struct debug_table, icount_save)); + DEFINE(DT_ICOUNT_LEVEL_SAVE, + offsetof(struct debug_table, icount_level_save)); +#endif + return 0; } diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index db5c1765b413..fe8f7e7efb9d 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -543,6 +543,12 @@ common_exception_return: #endif 5: +#ifdef CONFIG_HAVE_HW_BREAKPOINT + _bbci.l a4, TIF_DB_DISABLED, 7f + movi a4, restore_dbreak + callx4 a4 +7: +#endif #ifdef CONFIG_DEBUG_TLB_SANITY l32i a4, a1, PT_DEPC bgeui a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 4f @@ -789,39 +795,99 @@ ENTRY(debug_exception) movi a2, 1 << PS_EXCM_BIT or a2, a0, a2 - movi a0, debug_exception # restore a3, debug jump vector wsr a2, ps - xsr a0, SREG_EXCSAVE + XCHAL_DEBUGLEVEL /* Switch to kernel/user stack, restore jump vector, and save a0 */ bbsi.l a2, PS_UM_BIT, 2f # jump if user mode addi a2, a1, -16-PT_SIZE # assume kernel stack +3: + l32i a0, a3, DT_DEBUG_SAVE + s32i a1, a2, PT_AREG1 s32i a0, a2, PT_AREG0 movi a0, 0 - s32i a1, a2, PT_AREG1 s32i a0, a2, PT_DEPC # mark it as a regular exception + xsr a3, SREG_EXCSAVE + XCHAL_DEBUGLEVEL xsr a0, depc s32i a3, a2, PT_AREG3 s32i a0, a2, PT_AREG2 mov a1, a2 + + /* Debug exception is handled as an exception, so interrupts will + * likely be enabled in the common exception handler. Disable + * preemption if we have HW breakpoints to preserve DEBUGCAUSE.DBNUM + * meaning. + */ +#if defined(CONFIG_PREEMPT_COUNT) && defined(CONFIG_HAVE_HW_BREAKPOINT) + GET_THREAD_INFO(a2, a1) + l32i a3, a2, TI_PRE_COUNT + addi a3, a3, 1 + s32i a3, a2, TI_PRE_COUNT +#endif + + rsr a2, ps + bbsi.l a2, PS_UM_BIT, _user_exception j _kernel_exception 2: rsr a2, excsave1 l32i a2, a2, EXC_TABLE_KSTK # load kernel stack pointer - s32i a0, a2, PT_AREG0 + j 3b + +#ifdef CONFIG_HAVE_HW_BREAKPOINT + /* Debug exception while in exception mode. This may happen when + * window overflow/underflow handler or fast exception handler hits + * data breakpoint, in which case save and disable all data + * breakpoints, single-step faulting instruction and restore data + * breakpoints. + */ +1: + bbci.l a0, PS_UM_BIT, 1b # jump if kernel mode + + rsr a0, debugcause + bbsi.l a0, DEBUGCAUSE_DBREAK_BIT, .Ldebug_save_dbreak + + .set _index, 0 + .rept XCHAL_NUM_DBREAK + l32i a0, a3, DT_DBREAKC_SAVE + _index * 4 + wsr a0, SREG_DBREAKC + _index + .set _index, _index + 1 + .endr + + l32i a0, a3, DT_ICOUNT_LEVEL_SAVE + wsr a0, icountlevel + + l32i a0, a3, DT_ICOUNT_SAVE + xsr a0, icount + + l32i a0, a3, DT_DEBUG_SAVE + xsr a3, SREG_EXCSAVE + XCHAL_DEBUGLEVEL + rfi XCHAL_DEBUGLEVEL + +.Ldebug_save_dbreak: + .set _index, 0 + .rept XCHAL_NUM_DBREAK movi a0, 0 - s32i a1, a2, PT_AREG1 - s32i a0, a2, PT_DEPC - xsr a0, depc - s32i a3, a2, PT_AREG3 - s32i a0, a2, PT_AREG2 - mov a1, a2 - j _user_exception + xsr a0, SREG_DBREAKC + _index + s32i a0, a3, DT_DBREAKC_SAVE + _index * 4 + .set _index, _index + 1 + .endr - /* Debug exception while in exception mode. */ + movi a0, XCHAL_EXCM_LEVEL + 1 + xsr a0, icountlevel + s32i a0, a3, DT_ICOUNT_LEVEL_SAVE + + movi a0, 0xfffffffe + xsr a0, icount + s32i a0, a3, DT_ICOUNT_SAVE + + l32i a0, a3, DT_DEBUG_SAVE + xsr a3, SREG_EXCSAVE + XCHAL_DEBUGLEVEL + rfi XCHAL_DEBUGLEVEL +#else + /* Debug exception while in exception mode. Should not happen. */ 1: j 1b // FIXME!! +#endif ENDPROC(debug_exception) diff --git a/arch/xtensa/kernel/head.S b/arch/xtensa/kernel/head.S index 9ed55649ac8e..bc4f4bf05099 100644 --- a/arch/xtensa/kernel/head.S +++ b/arch/xtensa/kernel/head.S @@ -128,7 +128,7 @@ ENTRY(_startup) wsr a0, icountlevel .set _index, 0 - .rept XCHAL_NUM_DBREAK - 1 + .rept XCHAL_NUM_DBREAK wsr a0, SREG_DBREAKC + _index .set _index, _index + 1 .endr @@ -197,11 +197,6 @@ ENTRY(_startup) wsr a2, ps # (enable reg-windows; progmode stack) rsync - /* Set up EXCSAVE[DEBUGLEVEL] to point to the Debug Exception Handler.*/ - - movi a2, debug_exception - wsr a2, SREG_EXCSAVE + XCHAL_DEBUGLEVEL - #ifdef CONFIG_SMP /* * Notice that we assume with SMP that cores have PRID diff --git a/arch/xtensa/kernel/hw_breakpoint.c b/arch/xtensa/kernel/hw_breakpoint.c new file mode 100644 index 000000000000..b35656ab7dbd --- /dev/null +++ b/arch/xtensa/kernel/hw_breakpoint.c @@ -0,0 +1,317 @@ +/* + * Xtensa hardware breakpoints/watchpoints handling functions + * + * 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. + * + * Copyright (C) 2016 Cadence Design Systems Inc. + */ + +#include <linux/hw_breakpoint.h> +#include <linux/log2.h> +#include <linux/percpu.h> +#include <linux/perf_event.h> +#include <variant/core.h> + +/* Breakpoint currently in use for each IBREAKA. */ +static DEFINE_PER_CPU(struct perf_event *, bp_on_reg[XCHAL_NUM_IBREAK]); + +/* Watchpoint currently in use for each DBREAKA. */ +static DEFINE_PER_CPU(struct perf_event *, wp_on_reg[XCHAL_NUM_DBREAK]); + +int hw_breakpoint_slots(int type) +{ + switch (type) { + case TYPE_INST: + return XCHAL_NUM_IBREAK; + case TYPE_DATA: + return XCHAL_NUM_DBREAK; + default: + pr_warn("unknown slot type: %d\n", type); + return 0; + } +} + +int arch_check_bp_in_kernelspace(struct perf_event *bp) +{ + unsigned int len; + unsigned long va; + struct arch_hw_breakpoint *info = counter_arch_bp(bp); + + va = info->address; + len = bp->attr.bp_len; + + return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE); +} + +/* + * Construct an arch_hw_breakpoint from a perf_event. + */ +static int arch_build_bp_info(struct perf_event *bp) +{ + struct arch_hw_breakpoint *info = counter_arch_bp(bp); + + /* Type */ + switch (bp->attr.bp_type) { + case HW_BREAKPOINT_X: + info->type = XTENSA_BREAKPOINT_EXECUTE; + break; + case HW_BREAKPOINT_R: + info->type = XTENSA_BREAKPOINT_LOAD; + break; + case HW_BREAKPOINT_W: + info->type = XTENSA_BREAKPOINT_STORE; + break; + case HW_BREAKPOINT_RW: + info->type = XTENSA_BREAKPOINT_LOAD | XTENSA_BREAKPOINT_STORE; + break; + default: + return -EINVAL; + } + + /* Len */ + info->len = bp->attr.bp_len; + if (info->len < 1 || info->len > 64 || !is_power_of_2(info->len)) + return -EINVAL; + + /* Address */ + info->address = bp->attr.bp_addr; + if (info->address & (info->len - 1)) + return -EINVAL; + + return 0; +} + +int arch_validate_hwbkpt_settings(struct perf_event *bp) +{ + int ret; + + /* Build the arch_hw_breakpoint. */ + ret = arch_build_bp_info(bp); + return ret; +} + +int hw_breakpoint_exceptions_notify(struct notifier_block *unused, + unsigned long val, void *data) +{ + return NOTIFY_DONE; +} + +static void xtensa_wsr(unsigned long v, u8 sr) +{ + /* We don't have indexed wsr and creating instruction dynamically + * doesn't seem worth it given how small XCHAL_NUM_IBREAK and + * XCHAL_NUM_DBREAK are. Thus the switch. In case build breaks here + * the switch below needs to be extended. + */ + BUILD_BUG_ON(XCHAL_NUM_IBREAK > 2); + BUILD_BUG_ON(XCHAL_NUM_DBREAK > 2); + + switch (sr) { +#if XCHAL_NUM_IBREAK > 0 + case SREG_IBREAKA + 0: + WSR(v, SREG_IBREAKA + 0); + break; +#endif +#if XCHAL_NUM_IBREAK > 1 + case SREG_IBREAKA + 1: + WSR(v, SREG_IBREAKA + 1); + break; +#endif + +#if XCHAL_NUM_DBREAK > 0 + case SREG_DBREAKA + 0: + WSR(v, SREG_DBREAKA + 0); + break; + case SREG_DBREAKC + 0: + WSR(v, SREG_DBREAKC + 0); + break; +#endif +#if XCHAL_NUM_DBREAK > 1 + case SREG_DBREAKA + 1: + WSR(v, SREG_DBREAKA + 1); + break; + + case SREG_DBREAKC + 1: + WSR(v, SREG_DBREAKC + 1); + break; +#endif + } +} + +static int alloc_slot(struct perf_event **slot, size_t n, + struct perf_event *bp) +{ + size_t i; + + for (i = 0; i < n; ++i) { + if (!slot[i]) { + slot[i] = bp; + return i; + } + } + return -EBUSY; +} + +static void set_ibreak_regs(int reg, struct perf_event *bp) +{ + struct arch_hw_breakpoint *info = counter_arch_bp(bp); + unsigned long ibreakenable; + + xtensa_wsr(info->address, SREG_IBREAKA + reg); + RSR(ibreakenable, SREG_IBREAKENABLE); + WSR(ibreakenable | (1 << reg), SREG_IBREAKENABLE); +} + +static void set_dbreak_regs(int reg, struct perf_event *bp) +{ + struct arch_hw_breakpoint *info = counter_arch_bp(bp); + unsigned long dbreakc = DBREAKC_MASK_MASK & -info->len; + + if (info->type & XTENSA_BREAKPOINT_LOAD) + dbreakc |= DBREAKC_LOAD_MASK; + if (info->type & XTENSA_BREAKPOINT_STORE) + dbreakc |= DBREAKC_STOR_MASK; + + xtensa_wsr(info->address, SREG_DBREAKA + reg); + xtensa_wsr(dbreakc, SREG_DBREAKC + reg); +} + +int arch_install_hw_breakpoint(struct perf_event *bp) +{ + int i; + + if (counter_arch_bp(bp)->type == XTENSA_BREAKPOINT_EXECUTE) { + /* Breakpoint */ + i = alloc_slot(this_cpu_ptr(bp_on_reg), XCHAL_NUM_IBREAK, bp); + if (i < 0) + return i; + set_ibreak_regs(i, bp); + + } else { + /* Watchpoint */ + i = alloc_slot(this_cpu_ptr(wp_on_reg), XCHAL_NUM_DBREAK, bp); + if (i < 0) + return i; + set_dbreak_regs(i, bp); + } + return 0; +} + +static int free_slot(struct perf_event **slot, size_t n, + struct perf_event *bp) +{ + size_t i; + + for (i = 0; i < n; ++i) { + if (slot[i] == bp) { + slot[i] = NULL; + return i; + } + } + return -EBUSY; +} + +void arch_uninstall_hw_breakpoint(struct perf_event *bp) +{ + struct arch_hw_breakpoint *info = counter_arch_bp(bp); + int i; + + if (info->type == XTENSA_BREAKPOINT_EXECUTE) { + unsigned long ibreakenable; + + /* Breakpoint */ + i = free_slot(this_cpu_ptr(bp_on_reg), XCHAL_NUM_IBREAK, bp); + if (i >= 0) { + RSR(ibreakenable, SREG_IBREAKENABLE); + WSR(ibreakenable & ~(1 << i), SREG_IBREAKENABLE); + } + } else { + /* Watchpoint */ + i = free_slot(this_cpu_ptr(wp_on_reg), XCHAL_NUM_DBREAK, bp); + if (i >= 0) + xtensa_wsr(0, SREG_DBREAKC + i); + } +} + +void hw_breakpoint_pmu_read(struct perf_event *bp) +{ +} + +void flush_ptrace_hw_breakpoint(struct task_struct *tsk) +{ + int i; + struct thread_struct *t = &tsk->thread; + + for (i = 0; i < XCHAL_NUM_IBREAK; ++i) { + if (t->ptrace_bp[i]) { + unregister_hw_breakpoint(t->ptrace_bp[i]); + t->ptrace_bp[i] = NULL; + } + } + for (i = 0; i < XCHAL_NUM_DBREAK; ++i) { + if (t->ptrace_wp[i]) { + unregister_hw_breakpoint(t->ptrace_wp[i]); + t->ptrace_wp[i] = NULL; + } + } +} + +/* + * Set ptrace breakpoint pointers to zero for this task. + * This is required in order to prevent child processes from unregistering + * breakpoints held by their parent. + */ +void clear_ptrace_hw_breakpoint(struct task_struct *tsk) +{ + memset(tsk->thread.ptrace_bp, 0, sizeof(tsk->thread.ptrace_bp)); |