diff options
Diffstat (limited to 'arch/parisc/kernel/kgdb.c')
| -rw-r--r-- | arch/parisc/kernel/kgdb.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/arch/parisc/kernel/kgdb.c b/arch/parisc/kernel/kgdb.c new file mode 100644 index 000000000000..664278db9b97 --- /dev/null +++ b/arch/parisc/kernel/kgdb.c @@ -0,0 +1,209 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PA-RISC KGDB support + * + * Copyright (c) 2019 Sven Schnelle <svens@stackframe.org> + * + */ + +#include <linux/kgdb.h> +#include <linux/string.h> +#include <linux/sched.h> +#include <linux/notifier.h> +#include <linux/kdebug.h> +#include <linux/uaccess.h> +#include <asm/ptrace.h> +#include <asm/traps.h> +#include <asm/processor.h> +#include <asm/patch.h> +#include <asm/cacheflush.h> + +const struct kgdb_arch arch_kgdb_ops = { + .gdb_bpt_instr = { 0x03, 0xff, 0xa0, 0x1f } +}; + +static int __kgdb_notify(struct die_args *args, unsigned long cmd) +{ + struct pt_regs *regs = args->regs; + + if (kgdb_handle_exception(1, args->signr, cmd, regs)) + return NOTIFY_DONE; + return NOTIFY_STOP; +} + +static int kgdb_notify(struct notifier_block *self, + unsigned long cmd, void *ptr) +{ + unsigned long flags; + int ret; + + local_irq_save(flags); + ret = __kgdb_notify(ptr, cmd); + local_irq_restore(flags); + + return ret; +} + +static struct notifier_block kgdb_notifier = { + .notifier_call = kgdb_notify, + .priority = -INT_MAX, +}; + +int kgdb_arch_init(void) +{ + return register_die_notifier(&kgdb_notifier); +} + +void kgdb_arch_exit(void) +{ + unregister_die_notifier(&kgdb_notifier); +} + +void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + struct parisc_gdb_regs *gr = (struct parisc_gdb_regs *)gdb_regs; + + memset(gr, 0, sizeof(struct parisc_gdb_regs)); + + memcpy(gr->gpr, regs->gr, sizeof(gr->gpr)); + memcpy(gr->fr, regs->fr, sizeof(gr->fr)); + + gr->sr0 = regs->sr[0]; + gr->sr1 = regs->sr[1]; + gr->sr2 = regs->sr[2]; + gr->sr3 = regs->sr[3]; + gr->sr4 = regs->sr[4]; + gr->sr5 = regs->sr[5]; + gr->sr6 = regs->sr[6]; + gr->sr7 = regs->sr[7]; + + gr->sar = regs->sar; + gr->iir = regs->iir; + gr->isr = regs->isr; + gr->ior = regs->ior; + gr->ipsw = regs->ipsw; + gr->cr27 = regs->cr27; + + gr->iaoq_f = regs->iaoq[0]; + gr->iasq_f = regs->iasq[0]; + + gr->iaoq_b = regs->iaoq[1]; + gr->iasq_b = regs->iasq[1]; +} + +void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + struct parisc_gdb_regs *gr = (struct parisc_gdb_regs *)gdb_regs; + + + memcpy(regs->gr, gr->gpr, sizeof(regs->gr)); + memcpy(regs->fr, gr->fr, sizeof(regs->fr)); + + regs->sr[0] = gr->sr0; + regs->sr[1] = gr->sr1; + regs->sr[2] = gr->sr2; + regs->sr[3] = gr->sr3; + regs->sr[4] = gr->sr4; + regs->sr[5] = gr->sr5; + regs->sr[6] = gr->sr6; + regs->sr[7] = gr->sr7; + + regs->sar = gr->sar; + regs->iir = gr->iir; + regs->isr = gr->isr; + regs->ior = gr->ior; + regs->ipsw = gr->ipsw; + regs->cr27 = gr->cr27; + + regs->iaoq[0] = gr->iaoq_f; + regs->iasq[0] = gr->iasq_f; + + regs->iaoq[1] = gr->iaoq_b; + regs->iasq[1] = gr->iasq_b; +} + +void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, + struct task_struct *task) +{ + struct pt_regs *regs = task_pt_regs(task); + unsigned long gr30, iaoq; + + gr30 = regs->gr[30]; + iaoq = regs->iaoq[0]; + + regs->gr[30] = regs->ksp; + regs->iaoq[0] = regs->kpc; + pt_regs_to_gdb_regs(gdb_regs, regs); + + regs->gr[30] = gr30; + regs->iaoq[0] = iaoq; + +} + +static void step_instruction_queue(struct pt_regs *regs) +{ + regs->iaoq[0] = regs->iaoq[1]; + regs->iaoq[1] += 4; +} + +void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip) +{ + regs->iaoq[0] = ip; + regs->iaoq[1] = ip + 4; +} + +int kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt) +{ + int ret = probe_kernel_read(bpt->saved_instr, (char *)bpt->bpt_addr, + BREAK_INSTR_SIZE); + if (ret) + return ret; + + __patch_text((void *)bpt->bpt_addr, + *(unsigned int *)&arch_kgdb_ops.gdb_bpt_instr); + return ret; +} + +int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt) +{ + __patch_text((void *)bpt->bpt_addr, *(unsigned int *)&bpt->saved_instr); + return 0; +} + +int kgdb_arch_handle_exception(int trap, int signo, + int err_code, char *inbuf, char *outbuf, + struct pt_regs *regs) +{ + unsigned long addr; + char *p = inbuf + 1; + + switch (inbuf[0]) { + case 'D': + case 'c': + case 'k': + kgdb_contthread = NULL; + kgdb_single_step = 0; + + if (kgdb_hex2long(&p, &addr)) + kgdb_arch_set_pc(regs, addr); + else if (trap == 9 && regs->iir == + PARISC_KGDB_COMPILED_BREAK_INSN) + step_instruction_queue(regs); + return 0; + case 's': + kgdb_single_step = 1; + if (kgdb_hex2long(&p, &addr)) { + kgdb_arch_set_pc(regs, addr); + } else if (trap == 9 && regs->iir == + PARISC_KGDB_COMPILED_BREAK_INSN) { + step_instruction_queue(regs); + mtctl(-1, 0); + } else { + mtctl(0, 0); + } + regs->gr[0] |= PSW_R; + return 0; + + } + return -1; +} |