diff options
author | Mike Travis <travis@sgi.com> | 2009-01-01 04:34:16 +0300 |
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committer | Ingo Molnar <mingo@elte.hu> | 2009-01-03 20:53:31 +0300 |
commit | 7eb19553369c46cc1fa64caf120cbcab1b597f7c (patch) | |
tree | ef1a3beae706b9497c845d0a2557ceb4d2754998 /arch/sh/kernel/kgdb.c | |
parent | 6092848a2a23b660150a38bc06f59d75838d70c8 (diff) | |
parent | 8c384cdee3e04d6194a2c2b192b624754f990835 (diff) | |
download | linux-7eb19553369c46cc1fa64caf120cbcab1b597f7c.tar.xz |
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask into merge-rr-cpumask
Conflicts:
arch/x86/kernel/io_apic.c
kernel/rcuclassic.c
kernel/sched.c
kernel/time/tick-sched.c
Signed-off-by: Mike Travis <travis@sgi.com>
[ mingo@elte.hu: backmerged typo fix for io_apic.c ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/sh/kernel/kgdb.c')
-rw-r--r-- | arch/sh/kernel/kgdb.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/arch/sh/kernel/kgdb.c b/arch/sh/kernel/kgdb.c new file mode 100644 index 000000000000..7c747e7d71b8 --- /dev/null +++ b/arch/sh/kernel/kgdb.c @@ -0,0 +1,285 @@ +/* + * SuperH KGDB support + * + * Copyright (C) 2008 Paul Mundt + * + * Single stepping taken from the old stub by Henry Bell and Jeremy Siegel. + * + * 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/kgdb.h> +#include <linux/kdebug.h> +#include <linux/irq.h> +#include <linux/io.h> +#include <asm/cacheflush.h> + +char in_nmi = 0; /* Set during NMI to prevent re-entry */ + +/* Macros for single step instruction identification */ +#define OPCODE_BT(op) (((op) & 0xff00) == 0x8900) +#define OPCODE_BF(op) (((op) & 0xff00) == 0x8b00) +#define OPCODE_BTF_DISP(op) (((op) & 0x80) ? (((op) | 0xffffff80) << 1) : \ + (((op) & 0x7f ) << 1)) +#define OPCODE_BFS(op) (((op) & 0xff00) == 0x8f00) +#define OPCODE_BTS(op) (((op) & 0xff00) == 0x8d00) +#define OPCODE_BRA(op) (((op) & 0xf000) == 0xa000) +#define OPCODE_BRA_DISP(op) (((op) & 0x800) ? (((op) | 0xfffff800) << 1) : \ + (((op) & 0x7ff) << 1)) +#define OPCODE_BRAF(op) (((op) & 0xf0ff) == 0x0023) +#define OPCODE_BRAF_REG(op) (((op) & 0x0f00) >> 8) +#define OPCODE_BSR(op) (((op) & 0xf000) == 0xb000) +#define OPCODE_BSR_DISP(op) (((op) & 0x800) ? (((op) | 0xfffff800) << 1) : \ + (((op) & 0x7ff) << 1)) +#define OPCODE_BSRF(op) (((op) & 0xf0ff) == 0x0003) +#define OPCODE_BSRF_REG(op) (((op) >> 8) & 0xf) +#define OPCODE_JMP(op) (((op) & 0xf0ff) == 0x402b) +#define OPCODE_JMP_REG(op) (((op) >> 8) & 0xf) +#define OPCODE_JSR(op) (((op) & 0xf0ff) == 0x400b) +#define OPCODE_JSR_REG(op) (((op) >> 8) & 0xf) +#define OPCODE_RTS(op) ((op) == 0xb) +#define OPCODE_RTE(op) ((op) == 0x2b) + +#define SR_T_BIT_MASK 0x1 +#define STEP_OPCODE 0xc33d + +/* Calculate the new address for after a step */ +static short *get_step_address(struct pt_regs *linux_regs) +{ + opcode_t op = __raw_readw(linux_regs->pc); + long addr; + + /* BT */ + if (OPCODE_BT(op)) { + if (linux_regs->sr & SR_T_BIT_MASK) + addr = linux_regs->pc + 4 + OPCODE_BTF_DISP(op); + else + addr = linux_regs->pc + 2; + } + + /* BTS */ + else if (OPCODE_BTS(op)) { + if (linux_regs->sr & SR_T_BIT_MASK) + addr = linux_regs->pc + 4 + OPCODE_BTF_DISP(op); + else + addr = linux_regs->pc + 4; /* Not in delay slot */ + } + + /* BF */ + else if (OPCODE_BF(op)) { + if (!(linux_regs->sr & SR_T_BIT_MASK)) + addr = linux_regs->pc + 4 + OPCODE_BTF_DISP(op); + else + addr = linux_regs->pc + 2; + } + + /* BFS */ + else if (OPCODE_BFS(op)) { + if (!(linux_regs->sr & SR_T_BIT_MASK)) + addr = linux_regs->pc + 4 + OPCODE_BTF_DISP(op); + else + addr = linux_regs->pc + 4; /* Not in delay slot */ + } + + /* BRA */ + else if (OPCODE_BRA(op)) + addr = linux_regs->pc + 4 + OPCODE_BRA_DISP(op); + + /* BRAF */ + else if (OPCODE_BRAF(op)) + addr = linux_regs->pc + 4 + + linux_regs->regs[OPCODE_BRAF_REG(op)]; + + /* BSR */ + else if (OPCODE_BSR(op)) + addr = linux_regs->pc + 4 + OPCODE_BSR_DISP(op); + + /* BSRF */ + else if (OPCODE_BSRF(op)) + addr = linux_regs->pc + 4 + + linux_regs->regs[OPCODE_BSRF_REG(op)]; + + /* JMP */ + else if (OPCODE_JMP(op)) + addr = linux_regs->regs[OPCODE_JMP_REG(op)]; + + /* JSR */ + else if (OPCODE_JSR(op)) + addr = linux_regs->regs[OPCODE_JSR_REG(op)]; + + /* RTS */ + else if (OPCODE_RTS(op)) + addr = linux_regs->pr; + + /* RTE */ + else if (OPCODE_RTE(op)) + addr = linux_regs->regs[15]; + + /* Other */ + else + addr = linux_regs->pc + instruction_size(op); + + flush_icache_range(addr, addr + instruction_size(op)); + return (short *)addr; +} + +/* + * Replace the instruction immediately after the current instruction + * (i.e. next in the expected flow of control) with a trap instruction, + * so that returning will cause only a single instruction to be executed. + * Note that this model is slightly broken for instructions with delay + * slots (e.g. B[TF]S, BSR, BRA etc), where both the branch and the + * instruction in the delay slot will be executed. + */ + +static unsigned long stepped_address; +static opcode_t stepped_opcode; + +static void do_single_step(struct pt_regs *linux_regs) +{ + /* Determine where the target instruction will send us to */ + unsigned short *addr = get_step_address(linux_regs); + + stepped_address = (int)addr; + + /* Replace it */ + stepped_opcode = __raw_readw((long)addr); + *addr = STEP_OPCODE; + + /* Flush and return */ + flush_icache_range((long)addr, (long)addr + + instruction_size(stepped_opcode)); +} + +/* Undo a single step */ +static void undo_single_step(struct pt_regs *linux_regs) +{ + /* If we have stepped, put back the old instruction */ + /* Use stepped_address in case we stopped elsewhere */ + if (stepped_opcode != 0) { + __raw_writew(stepped_opcode, stepped_address); + flush_icache_range(stepped_address, stepped_address + 2); + } + + stepped_opcode = 0; +} + +void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + int i; + + for (i = 0; i < 16; i++) + gdb_regs[GDB_R0 + i] = regs->regs[i]; + + gdb_regs[GDB_PC] = regs->pc; + gdb_regs[GDB_PR] = regs->pr; + gdb_regs[GDB_SR] = regs->sr; + gdb_regs[GDB_GBR] = regs->gbr; + gdb_regs[GDB_MACH] = regs->mach; + gdb_regs[GDB_MACL] = regs->macl; + + __asm__ __volatile__ ("stc vbr, %0" : "=r" (gdb_regs[GDB_VBR])); +} + +void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + int i; + + for (i = 0; i < 16; i++) + regs->regs[GDB_R0 + i] = gdb_regs[GDB_R0 + i]; + + regs->pc = gdb_regs[GDB_PC]; + regs->pr = gdb_regs[GDB_PR]; + regs->sr = gdb_regs[GDB_SR]; + regs->gbr = gdb_regs[GDB_GBR]; + regs->mach = gdb_regs[GDB_MACH]; + regs->macl = gdb_regs[GDB_MACL]; + + __asm__ __volatile__ ("ldc %0, vbr" : : "r" (gdb_regs[GDB_VBR])); +} + +void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) +{ + gdb_regs[GDB_R15] = p->thread.sp; + gdb_regs[GDB_PC] = p->thread.pc; +} + +int kgdb_arch_handle_exception(int e_vector, int signo, int err_code, + char *remcomInBuffer, char *remcomOutBuffer, + struct pt_regs *linux_regs) +{ + unsigned long addr; + char *ptr; + + /* Undo any stepping we may have done */ + undo_single_step(linux_regs); + + switch (remcomInBuffer[0]) { + case 'c': + case 's': + /* try to read optional parameter, pc unchanged if no parm */ + ptr = &remcomInBuffer[1]; + if (kgdb_hex2long(&ptr, &addr)) + linux_regs->pc = addr; + case 'D': + case 'k': + atomic_set(&kgdb_cpu_doing_single_step, -1); + + if (remcomInBuffer[0] == 's') { + do_single_step(linux_regs); + kgdb_single_step = 1; + + atomic_set(&kgdb_cpu_doing_single_step, + raw_smp_processor_id()); + } + + return 0; + } + + /* this means that we do not want to exit from the handler: */ + return -1; +} + +/* + * The primary entry points for the kgdb debug trap table entries. + */ +BUILD_TRAP_HANDLER(singlestep) +{ + unsigned long flags; + TRAP_HANDLER_DECL; + + local_irq_save(flags); + regs->pc -= instruction_size(__raw_readw(regs->pc - 4)); + kgdb_handle_exception(vec >> 2, SIGTRAP, 0, regs); + local_irq_restore(flags); +} + + +BUILD_TRAP_HANDLER(breakpoint) +{ + unsigned long flags; + TRAP_HANDLER_DECL; + + local_irq_save(flags); + kgdb_handle_exception(vec >> 2, SIGTRAP, 0, regs); + local_irq_restore(flags); +} + +int kgdb_arch_init(void) +{ + return 0; +} + +void kgdb_arch_exit(void) +{ +} + +struct kgdb_arch arch_kgdb_ops = { + /* Breakpoint instruction: trapa #0x3c */ +#ifdef CONFIG_CPU_LITTLE_ENDIAN + .gdb_bpt_instr = { 0x3c, 0xc3 }, +#else + .gdb_bpt_instr = { 0xc3, 0x3c }, +#endif +}; |