| Message ID | 1586655721-22567-3-git-send-email-vincent.chen@sifive.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | riscv: Add KGDB and KDB support | expand |
On Sun, 12 Apr 2020 at 08:19, Vincent Chen <vincent.chen@sifive.com> wrote: > > The skeleton of RISC-V KGDB port. > > Signed-off-by: Vincent Chen <vincent.chen@sifive.com> > Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> > --- > arch/riscv/Kconfig | 1 + > arch/riscv/include/asm/kdebug.h | 12 +++ > arch/riscv/include/asm/kgdb.h | 107 +++++++++++++++++++++ > arch/riscv/kernel/Makefile | 1 + > arch/riscv/kernel/kgdb.c | 200 ++++++++++++++++++++++++++++++++++++++++ > arch/riscv/kernel/traps.c | 5 + > 6 files changed, 326 insertions(+) > create mode 100644 arch/riscv/include/asm/kdebug.h > create mode 100644 arch/riscv/include/asm/kgdb.h > create mode 100644 arch/riscv/kernel/kgdb.c > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index a197258595ef..7db9a81cda75 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -68,6 +68,7 @@ config RISCV > select ARCH_HAS_GCOV_PROFILE_ALL > select HAVE_COPY_THREAD_TLS > select HAVE_ARCH_KASAN if MMU && 64BIT > + select HAVE_ARCH_KGDB > > config ARCH_MMAP_RND_BITS_MIN > default 18 if 64BIT > diff --git a/arch/riscv/include/asm/kdebug.h b/arch/riscv/include/asm/kdebug.h > new file mode 100644 > index 000000000000..85ac00411f6e > --- /dev/null > +++ b/arch/riscv/include/asm/kdebug.h > @@ -0,0 +1,12 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > + > +#ifndef _ASM_ARC_KDEBUG_H > +#define _ASM_ARC_KDEBUG_H > + > +enum die_val { > + DIE_UNUSED, > + DIE_TRAP, > + DIE_OOPS > +}; > + > +#endif > diff --git a/arch/riscv/include/asm/kgdb.h b/arch/riscv/include/asm/kgdb.h > new file mode 100644 > index 000000000000..69bc6a03081d > --- /dev/null > +++ b/arch/riscv/include/asm/kgdb.h > @@ -0,0 +1,107 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > + > +#ifndef __ASM_KGDB_H_ > +#define __ASM_KGDB_H_ > + > +#ifdef __KERNEL__ > + > +#define GDB_SIZEOF_REG sizeof(unsigned long) > + > +#define DBG_MAX_REG_NUM (33) > +#define NUMREGBYTES ((DBG_MAX_REG_NUM) * GDB_SIZEOF_REG) > +#define CACHE_FLUSH_IS_SAFE 1 [...] > +#define BUFMAX 2048 > +#ifdef CONFIG_RISCV_ISA_C > +#define BREAK_INSTR_SIZE 2 > +#else > +#define BREAK_INSTR_SIZE 4 > +#endif > +#define CACHE_FLUSH_IS_SAFE 1 double macro definition? -Sumit > + > +#ifndef __ASSEMBLY__ > + > +extern int kgdb_has_hit_break(unsigned long addr); > +extern unsigned long kgdb_compiled_break; > + > +static inline void arch_kgdb_breakpoint(void) > +{ > + asm(".global kgdb_compiled_break\n" > + ".option norvc\n" > + "kgdb_compiled_break: ebreak\n" > + ".option rvc\n"); > +} > + > +#endif /* !__ASSEMBLY__ */ > + > +#define DBG_REG_ZERO "zero" > +#define DBG_REG_RA "ra" > +#define DBG_REG_SP "sp" > +#define DBG_REG_GP "gp" > +#define DBG_REG_TP "tp" > +#define DBG_REG_T0 "t0" > +#define DBG_REG_T1 "t1" > +#define DBG_REG_T2 "t2" > +#define DBG_REG_FP "fp" > +#define DBG_REG_S1 "s1" > +#define DBG_REG_A0 "a0" > +#define DBG_REG_A1 "a1" > +#define DBG_REG_A2 "a2" > +#define DBG_REG_A3 "a3" > +#define DBG_REG_A4 "a4" > +#define DBG_REG_A5 "a5" > +#define DBG_REG_A6 "a6" > +#define DBG_REG_A7 "a7" > +#define DBG_REG_S2 "s2" > +#define DBG_REG_S3 "s3" > +#define DBG_REG_S4 "s4" > +#define DBG_REG_S5 "s5" > +#define DBG_REG_S6 "s6" > +#define DBG_REG_S7 "s7" > +#define DBG_REG_S8 "s8" > +#define DBG_REG_S9 "s9" > +#define DBG_REG_S10 "s10" > +#define DBG_REG_S11 "s11" > +#define DBG_REG_T3 "t3" > +#define DBG_REG_T4 "t4" > +#define DBG_REG_T5 "t5" > +#define DBG_REG_T6 "t6" > +#define DBG_REG_EPC "pc" > + > +#define DBG_REG_ZERO_OFF 0 > +#define DBG_REG_RA_OFF 1 > +#define DBG_REG_SP_OFF 2 > +#define DBG_REG_GP_OFF 3 > +#define DBG_REG_TP_OFF 4 > +#define DBG_REG_T0_OFF 5 > +#define DBG_REG_T1_OFF 6 > +#define DBG_REG_T2_OFF 7 > +#define DBG_REG_FP_OFF 8 > +#define DBG_REG_S1_OFF 9 > +#define DBG_REG_A0_OFF 10 > +#define DBG_REG_A1_OFF 11 > +#define DBG_REG_A2_OFF 12 > +#define DBG_REG_A3_OFF 13 > +#define DBG_REG_A4_OFF 14 > +#define DBG_REG_A5_OFF 15 > +#define DBG_REG_A6_OFF 16 > +#define DBG_REG_A7_OFF 17 > +#define DBG_REG_S2_OFF 18 > +#define DBG_REG_S3_OFF 19 > +#define DBG_REG_S4_OFF 20 > +#define DBG_REG_S5_OFF 21 > +#define DBG_REG_S6_OFF 22 > +#define DBG_REG_S7_OFF 23 > +#define DBG_REG_S8_OFF 24 > +#define DBG_REG_S9_OFF 25 > +#define DBG_REG_S10_OFF 26 > +#define DBG_REG_S11_OFF 27 > +#define DBG_REG_T3_OFF 28 > +#define DBG_REG_T4_OFF 29 > +#define DBG_REG_T5_OFF 30 > +#define DBG_REG_T6_OFF 31 > +#define DBG_REG_EPC_OFF 32 > +#define DBG_REG_STATUS_OFF 33 > +#define DBG_REG_BADADDR_OFF 34 > +#define DBG_REG_CAUSE_OFF 35 > +#endif > +#endif > diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile > index 86c83081044f..1f5736e996fd 100644 > --- a/arch/riscv/kernel/Makefile > +++ b/arch/riscv/kernel/Makefile > @@ -51,5 +51,6 @@ ifeq ($(CONFIG_RISCV_SBI), y) > obj-$(CONFIG_SMP) += cpu_ops_sbi.o > endif > obj-$(CONFIG_HOTPLUG_CPU) += cpu-hotplug.o > +obj-$(CONFIG_KGDB) += kgdb.o > > clean: > diff --git a/arch/riscv/kernel/kgdb.c b/arch/riscv/kernel/kgdb.c > new file mode 100644 > index 000000000000..6bdc0908a5b8 > --- /dev/null > +++ b/arch/riscv/kernel/kgdb.c > @@ -0,0 +1,200 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2020 SiFive > + */ > + > +#include <linux/ptrace.h> > +#include <linux/kdebug.h> > +#include <linux/bug.h> > +#include <linux/kgdb.h> > +#include <linux/irqflags.h> > +#include <linux/string.h> > +#include <asm/cacheflush.h> > + > +enum { > + NOT_KGDB_BREAK = 0, > + KGDB_SW_BREAK, > + KGDB_COMPILED_BREAK, > +}; > + > +struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = { > + {DBG_REG_ZERO, GDB_SIZEOF_REG, -1}, > + {DBG_REG_RA, GDB_SIZEOF_REG, offsetof(struct pt_regs, ra)}, > + {DBG_REG_SP, GDB_SIZEOF_REG, offsetof(struct pt_regs, sp)}, > + {DBG_REG_GP, GDB_SIZEOF_REG, offsetof(struct pt_regs, gp)}, > + {DBG_REG_TP, GDB_SIZEOF_REG, offsetof(struct pt_regs, tp)}, > + {DBG_REG_T0, GDB_SIZEOF_REG, offsetof(struct pt_regs, t0)}, > + {DBG_REG_T1, GDB_SIZEOF_REG, offsetof(struct pt_regs, t1)}, > + {DBG_REG_T2, GDB_SIZEOF_REG, offsetof(struct pt_regs, t2)}, > + {DBG_REG_FP, GDB_SIZEOF_REG, offsetof(struct pt_regs, s0)}, > + {DBG_REG_S1, GDB_SIZEOF_REG, offsetof(struct pt_regs, a1)}, > + {DBG_REG_A0, GDB_SIZEOF_REG, offsetof(struct pt_regs, a0)}, > + {DBG_REG_A1, GDB_SIZEOF_REG, offsetof(struct pt_regs, a1)}, > + {DBG_REG_A2, GDB_SIZEOF_REG, offsetof(struct pt_regs, a2)}, > + {DBG_REG_A3, GDB_SIZEOF_REG, offsetof(struct pt_regs, a3)}, > + {DBG_REG_A4, GDB_SIZEOF_REG, offsetof(struct pt_regs, a4)}, > + {DBG_REG_A5, GDB_SIZEOF_REG, offsetof(struct pt_regs, a5)}, > + {DBG_REG_A6, GDB_SIZEOF_REG, offsetof(struct pt_regs, a6)}, > + {DBG_REG_A7, GDB_SIZEOF_REG, offsetof(struct pt_regs, a7)}, > + {DBG_REG_S2, GDB_SIZEOF_REG, offsetof(struct pt_regs, s2)}, > + {DBG_REG_S3, GDB_SIZEOF_REG, offsetof(struct pt_regs, s3)}, > + {DBG_REG_S4, GDB_SIZEOF_REG, offsetof(struct pt_regs, s4)}, > + {DBG_REG_S5, GDB_SIZEOF_REG, offsetof(struct pt_regs, s5)}, > + {DBG_REG_S6, GDB_SIZEOF_REG, offsetof(struct pt_regs, s6)}, > + {DBG_REG_S7, GDB_SIZEOF_REG, offsetof(struct pt_regs, s7)}, > + {DBG_REG_S8, GDB_SIZEOF_REG, offsetof(struct pt_regs, s8)}, > + {DBG_REG_S9, GDB_SIZEOF_REG, offsetof(struct pt_regs, s9)}, > + {DBG_REG_S10, GDB_SIZEOF_REG, offsetof(struct pt_regs, s10)}, > + {DBG_REG_S11, GDB_SIZEOF_REG, offsetof(struct pt_regs, s11)}, > + {DBG_REG_T3, GDB_SIZEOF_REG, offsetof(struct pt_regs, t3)}, > + {DBG_REG_T4, GDB_SIZEOF_REG, offsetof(struct pt_regs, t4)}, > + {DBG_REG_T5, GDB_SIZEOF_REG, offsetof(struct pt_regs, t5)}, > + {DBG_REG_T6, GDB_SIZEOF_REG, offsetof(struct pt_regs, t6)}, > + {DBG_REG_EPC, GDB_SIZEOF_REG, offsetof(struct pt_regs, epc)}, > +}; > + > +char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs) > +{ > + if (regno >= DBG_MAX_REG_NUM || regno < 0) > + return NULL; > + > + if (dbg_reg_def[regno].offset != -1) > + memcpy(mem, (void *)regs + dbg_reg_def[regno].offset, > + dbg_reg_def[regno].size); > + else > + memset(mem, 0, dbg_reg_def[regno].size); > + return dbg_reg_def[regno].name; > +} > + > +int dbg_set_reg(int regno, void *mem, struct pt_regs *regs) > +{ > + if (regno >= DBG_MAX_REG_NUM || regno < 0) > + return -EINVAL; > + > + if (dbg_reg_def[regno].offset != -1) > + memcpy((void *)regs + dbg_reg_def[regno].offset, mem, > + dbg_reg_def[regno].size); > + return 0; > +} > + > +void > +sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *task) > +{ > + /* Initialize to zero */ > + memset((char *)gdb_regs, 0, NUMREGBYTES); > + > + gdb_regs[DBG_REG_SP_OFF] = task->thread.sp; > + gdb_regs[DBG_REG_FP_OFF] = task->thread.s[0]; > + gdb_regs[DBG_REG_S1_OFF] = task->thread.s[1]; > + gdb_regs[DBG_REG_S2_OFF] = task->thread.s[2]; > + gdb_regs[DBG_REG_S3_OFF] = task->thread.s[3]; > + gdb_regs[DBG_REG_S4_OFF] = task->thread.s[4]; > + gdb_regs[DBG_REG_S5_OFF] = task->thread.s[5]; > + gdb_regs[DBG_REG_S6_OFF] = task->thread.s[6]; > + gdb_regs[DBG_REG_S7_OFF] = task->thread.s[7]; > + gdb_regs[DBG_REG_S8_OFF] = task->thread.s[8]; > + gdb_regs[DBG_REG_S9_OFF] = task->thread.s[10]; > + gdb_regs[DBG_REG_S10_OFF] = task->thread.s[11]; > + gdb_regs[DBG_REG_EPC_OFF] = task->thread.ra; > +} > + > +void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc) > +{ > + regs->epc = pc; > +} > + > +static inline void kgdb_arch_update_addr(struct pt_regs *regs, > + char *remcom_in_buffer) > +{ > + unsigned long addr; > + char *ptr; > + > + ptr = &remcom_in_buffer[1]; > + if (kgdb_hex2long(&ptr, &addr)) > + regs->epc = addr; > +} > + > +int kgdb_arch_handle_exception(int vector, int signo, int err_code, > + char *remcom_in_buffer, char *remcom_out_buffer, > + struct pt_regs *regs) > +{ > + int err = 0; > + > + switch (remcom_in_buffer[0]) { > + case 'c': > + case 'D': > + case 'k': > + if (remcom_in_buffer[0] == 'c') > + kgdb_arch_update_addr(regs, remcom_in_buffer); > + break; > + default: > + err = -1; > + } > + > + return err; > +} > + > +int kgdb_riscv_kgdbbreak(unsigned long addr) > +{ > + if (atomic_read(&kgdb_setting_breakpoint)) > + if (addr == (unsigned long)&kgdb_compiled_break) > + return KGDB_COMPILED_BREAK; > + > + return kgdb_has_hit_break(addr); > +} > + > +static int kgdb_riscv_notify(struct notifier_block *self, unsigned long cmd, > + void *ptr) > +{ > + struct die_args *args = (struct die_args *)ptr; > + struct pt_regs *regs = args->regs; > + unsigned long flags; > + int type; > + > + if (user_mode(regs)) > + return NOTIFY_DONE; > + > + type = kgdb_riscv_kgdbbreak(regs->epc); > + if (type == NOT_KGDB_BREAK && cmd == DIE_TRAP) > + return NOTIFY_DONE; > + > + local_irq_save(flags); > + if (kgdb_handle_exception(1, args->signr, cmd, regs)) > + return NOTIFY_DONE; > + > + if (type == KGDB_COMPILED_BREAK) > + regs->epc += 4; > + > + local_irq_restore(flags); > + > + return NOTIFY_STOP; > +} > + > +static struct notifier_block kgdb_notifier = { > + .notifier_call = kgdb_riscv_notify, > +}; > + > +int kgdb_arch_init(void) > +{ > + register_die_notifier(&kgdb_notifier); > + > + return 0; > +} > + > +void kgdb_arch_exit(void) > +{ > + unregister_die_notifier(&kgdb_notifier); > +} > + > +/* > + * Global data > + */ > +#ifdef CONFIG_RISCV_ISA_C > +const struct kgdb_arch arch_kgdb_ops = { > + .gdb_bpt_instr = {0x02, 0x90}, /* c.ebreak */ > +}; > +#else > +const struct kgdb_arch arch_kgdb_ops = { > + .gdb_bpt_instr = {0x73, 0x00, 0x10, 0x00}, /* ebreak */ > +}; > +#endif > diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c > index 7f58fa53033f..5080fdf8c296 100644 > --- a/arch/riscv/kernel/traps.c > +++ b/arch/riscv/kernel/traps.c > @@ -147,6 +147,11 @@ asmlinkage __visible void do_trap_break(struct pt_regs *regs) > { > if (user_mode(regs)) > force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->epc); > +#ifdef CONFIG_KGDB > + else if (notify_die(DIE_TRAP, "EBREAK", regs, 0, regs->cause, SIGTRAP) > + == NOTIFY_STOP) > + return; > +#endif > else if (report_bug(regs->epc, regs) == BUG_TRAP_TYPE_WARN) > regs->epc += get_break_insn_length(regs->epc); > else > -- > 2.7.4 > > > > _______________________________________________ > Kgdb-bugreport mailing list > Kgdb-bugreport@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport
On Wed, Apr 15, 2020 at 6:59 PM Sumit Garg <sumit.garg@linaro.org> wrote: > > On Sun, 12 Apr 2020 at 08:19, Vincent Chen <vincent.chen@sifive.com> wrote: > > > > The skeleton of RISC-V KGDB port. > > > > Signed-off-by: Vincent Chen <vincent.chen@sifive.com> > > Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> > > --- > > arch/riscv/Kconfig | 1 + > > arch/riscv/include/asm/kdebug.h | 12 +++ > > arch/riscv/include/asm/kgdb.h | 107 +++++++++++++++++++++ > > arch/riscv/kernel/Makefile | 1 + > > arch/riscv/kernel/kgdb.c | 200 ++++++++++++++++++++++++++++++++++++++++ > > arch/riscv/kernel/traps.c | 5 + > > 6 files changed, 326 insertions(+) > > create mode 100644 arch/riscv/include/asm/kdebug.h > > create mode 100644 arch/riscv/include/asm/kgdb.h > > create mode 100644 arch/riscv/kernel/kgdb.c > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > index a197258595ef..7db9a81cda75 100644 > > --- a/arch/riscv/Kconfig > > +++ b/arch/riscv/Kconfig > > @@ -68,6 +68,7 @@ config RISCV > > select ARCH_HAS_GCOV_PROFILE_ALL > > select HAVE_COPY_THREAD_TLS > > select HAVE_ARCH_KASAN if MMU && 64BIT > > + select HAVE_ARCH_KGDB > > > > config ARCH_MMAP_RND_BITS_MIN > > default 18 if 64BIT > > diff --git a/arch/riscv/include/asm/kdebug.h b/arch/riscv/include/asm/kdebug.h > > new file mode 100644 > > index 000000000000..85ac00411f6e > > --- /dev/null > > +++ b/arch/riscv/include/asm/kdebug.h > > @@ -0,0 +1,12 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > + > > +#ifndef _ASM_ARC_KDEBUG_H > > +#define _ASM_ARC_KDEBUG_H > > + > > +enum die_val { > > + DIE_UNUSED, > > + DIE_TRAP, > > + DIE_OOPS > > +}; > > + > > +#endif > > diff --git a/arch/riscv/include/asm/kgdb.h b/arch/riscv/include/asm/kgdb.h > > new file mode 100644 > > index 000000000000..69bc6a03081d > > --- /dev/null > > +++ b/arch/riscv/include/asm/kgdb.h > > @@ -0,0 +1,107 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > + > > +#ifndef __ASM_KGDB_H_ > > +#define __ASM_KGDB_H_ > > + > > +#ifdef __KERNEL__ > > + > > +#define GDB_SIZEOF_REG sizeof(unsigned long) > > + > > +#define DBG_MAX_REG_NUM (33) > > +#define NUMREGBYTES ((DBG_MAX_REG_NUM) * GDB_SIZEOF_REG) > > +#define CACHE_FLUSH_IS_SAFE 1 > > [...] > > > +#define BUFMAX 2048 > > +#ifdef CONFIG_RISCV_ISA_C > > +#define BREAK_INSTR_SIZE 2 > > +#else > > +#define BREAK_INSTR_SIZE 4 > > +#endif > > +#define CACHE_FLUSH_IS_SAFE 1 > > double macro definition? > Sorry for my neglect. I will remove the duplicated one in the next version patch. Thanks for your reminder.
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index a197258595ef..7db9a81cda75 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -68,6 +68,7 @@ config RISCV select ARCH_HAS_GCOV_PROFILE_ALL select HAVE_COPY_THREAD_TLS select HAVE_ARCH_KASAN if MMU && 64BIT + select HAVE_ARCH_KGDB config ARCH_MMAP_RND_BITS_MIN default 18 if 64BIT diff --git a/arch/riscv/include/asm/kdebug.h b/arch/riscv/include/asm/kdebug.h new file mode 100644 index 000000000000..85ac00411f6e --- /dev/null +++ b/arch/riscv/include/asm/kdebug.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#ifndef _ASM_ARC_KDEBUG_H +#define _ASM_ARC_KDEBUG_H + +enum die_val { + DIE_UNUSED, + DIE_TRAP, + DIE_OOPS +}; + +#endif diff --git a/arch/riscv/include/asm/kgdb.h b/arch/riscv/include/asm/kgdb.h new file mode 100644 index 000000000000..69bc6a03081d --- /dev/null +++ b/arch/riscv/include/asm/kgdb.h @@ -0,0 +1,107 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#ifndef __ASM_KGDB_H_ +#define __ASM_KGDB_H_ + +#ifdef __KERNEL__ + +#define GDB_SIZEOF_REG sizeof(unsigned long) + +#define DBG_MAX_REG_NUM (33) +#define NUMREGBYTES ((DBG_MAX_REG_NUM) * GDB_SIZEOF_REG) +#define CACHE_FLUSH_IS_SAFE 1 +#define BUFMAX 2048 +#ifdef CONFIG_RISCV_ISA_C +#define BREAK_INSTR_SIZE 2 +#else +#define BREAK_INSTR_SIZE 4 +#endif +#define CACHE_FLUSH_IS_SAFE 1 + +#ifndef __ASSEMBLY__ + +extern int kgdb_has_hit_break(unsigned long addr); +extern unsigned long kgdb_compiled_break; + +static inline void arch_kgdb_breakpoint(void) +{ + asm(".global kgdb_compiled_break\n" + ".option norvc\n" + "kgdb_compiled_break: ebreak\n" + ".option rvc\n"); +} + +#endif /* !__ASSEMBLY__ */ + +#define DBG_REG_ZERO "zero" +#define DBG_REG_RA "ra" +#define DBG_REG_SP "sp" +#define DBG_REG_GP "gp" +#define DBG_REG_TP "tp" +#define DBG_REG_T0 "t0" +#define DBG_REG_T1 "t1" +#define DBG_REG_T2 "t2" +#define DBG_REG_FP "fp" +#define DBG_REG_S1 "s1" +#define DBG_REG_A0 "a0" +#define DBG_REG_A1 "a1" +#define DBG_REG_A2 "a2" +#define DBG_REG_A3 "a3" +#define DBG_REG_A4 "a4" +#define DBG_REG_A5 "a5" +#define DBG_REG_A6 "a6" +#define DBG_REG_A7 "a7" +#define DBG_REG_S2 "s2" +#define DBG_REG_S3 "s3" +#define DBG_REG_S4 "s4" +#define DBG_REG_S5 "s5" +#define DBG_REG_S6 "s6" +#define DBG_REG_S7 "s7" +#define DBG_REG_S8 "s8" +#define DBG_REG_S9 "s9" +#define DBG_REG_S10 "s10" +#define DBG_REG_S11 "s11" +#define DBG_REG_T3 "t3" +#define DBG_REG_T4 "t4" +#define DBG_REG_T5 "t5" +#define DBG_REG_T6 "t6" +#define DBG_REG_EPC "pc" + +#define DBG_REG_ZERO_OFF 0 +#define DBG_REG_RA_OFF 1 +#define DBG_REG_SP_OFF 2 +#define DBG_REG_GP_OFF 3 +#define DBG_REG_TP_OFF 4 +#define DBG_REG_T0_OFF 5 +#define DBG_REG_T1_OFF 6 +#define DBG_REG_T2_OFF 7 +#define DBG_REG_FP_OFF 8 +#define DBG_REG_S1_OFF 9 +#define DBG_REG_A0_OFF 10 +#define DBG_REG_A1_OFF 11 +#define DBG_REG_A2_OFF 12 +#define DBG_REG_A3_OFF 13 +#define DBG_REG_A4_OFF 14 +#define DBG_REG_A5_OFF 15 +#define DBG_REG_A6_OFF 16 +#define DBG_REG_A7_OFF 17 +#define DBG_REG_S2_OFF 18 +#define DBG_REG_S3_OFF 19 +#define DBG_REG_S4_OFF 20 +#define DBG_REG_S5_OFF 21 +#define DBG_REG_S6_OFF 22 +#define DBG_REG_S7_OFF 23 +#define DBG_REG_S8_OFF 24 +#define DBG_REG_S9_OFF 25 +#define DBG_REG_S10_OFF 26 +#define DBG_REG_S11_OFF 27 +#define DBG_REG_T3_OFF 28 +#define DBG_REG_T4_OFF 29 +#define DBG_REG_T5_OFF 30 +#define DBG_REG_T6_OFF 31 +#define DBG_REG_EPC_OFF 32 +#define DBG_REG_STATUS_OFF 33 +#define DBG_REG_BADADDR_OFF 34 +#define DBG_REG_CAUSE_OFF 35 +#endif +#endif diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 86c83081044f..1f5736e996fd 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -51,5 +51,6 @@ ifeq ($(CONFIG_RISCV_SBI), y) obj-$(CONFIG_SMP) += cpu_ops_sbi.o endif obj-$(CONFIG_HOTPLUG_CPU) += cpu-hotplug.o +obj-$(CONFIG_KGDB) += kgdb.o clean: diff --git a/arch/riscv/kernel/kgdb.c b/arch/riscv/kernel/kgdb.c new file mode 100644 index 000000000000..6bdc0908a5b8 --- /dev/null +++ b/arch/riscv/kernel/kgdb.c @@ -0,0 +1,200 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 SiFive + */ + +#include <linux/ptrace.h> +#include <linux/kdebug.h> +#include <linux/bug.h> +#include <linux/kgdb.h> +#include <linux/irqflags.h> +#include <linux/string.h> +#include <asm/cacheflush.h> + +enum { + NOT_KGDB_BREAK = 0, + KGDB_SW_BREAK, + KGDB_COMPILED_BREAK, +}; + +struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = { + {DBG_REG_ZERO, GDB_SIZEOF_REG, -1}, + {DBG_REG_RA, GDB_SIZEOF_REG, offsetof(struct pt_regs, ra)}, + {DBG_REG_SP, GDB_SIZEOF_REG, offsetof(struct pt_regs, sp)}, + {DBG_REG_GP, GDB_SIZEOF_REG, offsetof(struct pt_regs, gp)}, + {DBG_REG_TP, GDB_SIZEOF_REG, offsetof(struct pt_regs, tp)}, + {DBG_REG_T0, GDB_SIZEOF_REG, offsetof(struct pt_regs, t0)}, + {DBG_REG_T1, GDB_SIZEOF_REG, offsetof(struct pt_regs, t1)}, + {DBG_REG_T2, GDB_SIZEOF_REG, offsetof(struct pt_regs, t2)}, + {DBG_REG_FP, GDB_SIZEOF_REG, offsetof(struct pt_regs, s0)}, + {DBG_REG_S1, GDB_SIZEOF_REG, offsetof(struct pt_regs, a1)}, + {DBG_REG_A0, GDB_SIZEOF_REG, offsetof(struct pt_regs, a0)}, + {DBG_REG_A1, GDB_SIZEOF_REG, offsetof(struct pt_regs, a1)}, + {DBG_REG_A2, GDB_SIZEOF_REG, offsetof(struct pt_regs, a2)}, + {DBG_REG_A3, GDB_SIZEOF_REG, offsetof(struct pt_regs, a3)}, + {DBG_REG_A4, GDB_SIZEOF_REG, offsetof(struct pt_regs, a4)}, + {DBG_REG_A5, GDB_SIZEOF_REG, offsetof(struct pt_regs, a5)}, + {DBG_REG_A6, GDB_SIZEOF_REG, offsetof(struct pt_regs, a6)}, + {DBG_REG_A7, GDB_SIZEOF_REG, offsetof(struct pt_regs, a7)}, + {DBG_REG_S2, GDB_SIZEOF_REG, offsetof(struct pt_regs, s2)}, + {DBG_REG_S3, GDB_SIZEOF_REG, offsetof(struct pt_regs, s3)}, + {DBG_REG_S4, GDB_SIZEOF_REG, offsetof(struct pt_regs, s4)}, + {DBG_REG_S5, GDB_SIZEOF_REG, offsetof(struct pt_regs, s5)}, + {DBG_REG_S6, GDB_SIZEOF_REG, offsetof(struct pt_regs, s6)}, + {DBG_REG_S7, GDB_SIZEOF_REG, offsetof(struct pt_regs, s7)}, + {DBG_REG_S8, GDB_SIZEOF_REG, offsetof(struct pt_regs, s8)}, + {DBG_REG_S9, GDB_SIZEOF_REG, offsetof(struct pt_regs, s9)}, + {DBG_REG_S10, GDB_SIZEOF_REG, offsetof(struct pt_regs, s10)}, + {DBG_REG_S11, GDB_SIZEOF_REG, offsetof(struct pt_regs, s11)}, + {DBG_REG_T3, GDB_SIZEOF_REG, offsetof(struct pt_regs, t3)}, + {DBG_REG_T4, GDB_SIZEOF_REG, offsetof(struct pt_regs, t4)}, + {DBG_REG_T5, GDB_SIZEOF_REG, offsetof(struct pt_regs, t5)}, + {DBG_REG_T6, GDB_SIZEOF_REG, offsetof(struct pt_regs, t6)}, + {DBG_REG_EPC, GDB_SIZEOF_REG, offsetof(struct pt_regs, epc)}, +}; + +char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs) +{ + if (regno >= DBG_MAX_REG_NUM || regno < 0) + return NULL; + + if (dbg_reg_def[regno].offset != -1) + memcpy(mem, (void *)regs + dbg_reg_def[regno].offset, + dbg_reg_def[regno].size); + else + memset(mem, 0, dbg_reg_def[regno].size); + return dbg_reg_def[regno].name; +} + +int dbg_set_reg(int regno, void *mem, struct pt_regs *regs) +{ + if (regno >= DBG_MAX_REG_NUM || regno < 0) + return -EINVAL; + + if (dbg_reg_def[regno].offset != -1) + memcpy((void *)regs + dbg_reg_def[regno].offset, mem, + dbg_reg_def[regno].size); + return 0; +} + +void +sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *task) +{ + /* Initialize to zero */ + memset((char *)gdb_regs, 0, NUMREGBYTES); + + gdb_regs[DBG_REG_SP_OFF] = task->thread.sp; + gdb_regs[DBG_REG_FP_OFF] = task->thread.s[0]; + gdb_regs[DBG_REG_S1_OFF] = task->thread.s[1]; + gdb_regs[DBG_REG_S2_OFF] = task->thread.s[2]; + gdb_regs[DBG_REG_S3_OFF] = task->thread.s[3]; + gdb_regs[DBG_REG_S4_OFF] = task->thread.s[4]; + gdb_regs[DBG_REG_S5_OFF] = task->thread.s[5]; + gdb_regs[DBG_REG_S6_OFF] = task->thread.s[6]; + gdb_regs[DBG_REG_S7_OFF] = task->thread.s[7]; + gdb_regs[DBG_REG_S8_OFF] = task->thread.s[8]; + gdb_regs[DBG_REG_S9_OFF] = task->thread.s[10]; + gdb_regs[DBG_REG_S10_OFF] = task->thread.s[11]; + gdb_regs[DBG_REG_EPC_OFF] = task->thread.ra; +} + +void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc) +{ + regs->epc = pc; +} + +static inline void kgdb_arch_update_addr(struct pt_regs *regs, + char *remcom_in_buffer) +{ + unsigned long addr; + char *ptr; + + ptr = &remcom_in_buffer[1]; + if (kgdb_hex2long(&ptr, &addr)) + regs->epc = addr; +} + +int kgdb_arch_handle_exception(int vector, int signo, int err_code, + char *remcom_in_buffer, char *remcom_out_buffer, + struct pt_regs *regs) +{ + int err = 0; + + switch (remcom_in_buffer[0]) { + case 'c': + case 'D': + case 'k': + if (remcom_in_buffer[0] == 'c') + kgdb_arch_update_addr(regs, remcom_in_buffer); + break; + default: + err = -1; + } + + return err; +} + +int kgdb_riscv_kgdbbreak(unsigned long addr) +{ + if (atomic_read(&kgdb_setting_breakpoint)) + if (addr == (unsigned long)&kgdb_compiled_break) + return KGDB_COMPILED_BREAK; + + return kgdb_has_hit_break(addr); +} + +static int kgdb_riscv_notify(struct notifier_block *self, unsigned long cmd, + void *ptr) +{ + struct die_args *args = (struct die_args *)ptr; + struct pt_regs *regs = args->regs; + unsigned long flags; + int type; + + if (user_mode(regs)) + return NOTIFY_DONE; + + type = kgdb_riscv_kgdbbreak(regs->epc); + if (type == NOT_KGDB_BREAK && cmd == DIE_TRAP) + return NOTIFY_DONE; + + local_irq_save(flags); + if (kgdb_handle_exception(1, args->signr, cmd, regs)) + return NOTIFY_DONE; + + if (type == KGDB_COMPILED_BREAK) + regs->epc += 4; + + local_irq_restore(flags); + + return NOTIFY_STOP; +} + +static struct notifier_block kgdb_notifier = { + .notifier_call = kgdb_riscv_notify, +}; + +int kgdb_arch_init(void) +{ + register_die_notifier(&kgdb_notifier); + + return 0; +} + +void kgdb_arch_exit(void) +{ + unregister_die_notifier(&kgdb_notifier); +} + +/* + * Global data + */ +#ifdef CONFIG_RISCV_ISA_C +const struct kgdb_arch arch_kgdb_ops = { + .gdb_bpt_instr = {0x02, 0x90}, /* c.ebreak */ +}; +#else +const struct kgdb_arch arch_kgdb_ops = { + .gdb_bpt_instr = {0x73, 0x00, 0x10, 0x00}, /* ebreak */ +}; +#endif diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 7f58fa53033f..5080fdf8c296 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -147,6 +147,11 @@ asmlinkage __visible void do_trap_break(struct pt_regs *regs) { if (user_mode(regs)) force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->epc); +#ifdef CONFIG_KGDB + else if (notify_die(DIE_TRAP, "EBREAK", regs, 0, regs->cause, SIGTRAP) + == NOTIFY_STOP) + return; +#endif else if (report_bug(regs->epc, regs) == BUG_TRAP_TYPE_WARN) regs->epc += get_break_insn_length(regs->epc); else