/* kgdb.c: KGDB support for 64-bit sparc. * * Copyright (C) 2008 David S. Miller <davem@davemloft.net> */ #include <linux/kgdb.h> #include <linux/kdebug.h> #include <linux/ftrace.h> #include <asm/kdebug.h> #include <asm/ptrace.h> #include <asm/irq.h> void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) { struct reg_window *win; int i; gdb_regs[GDB_G0] = 0; for (i = 0; i < 15; i++) gdb_regs[GDB_G1 + i] = regs->u_regs[UREG_G1 + i]; win = (struct reg_window *) (regs->u_regs[UREG_FP] + STACK_BIAS); for (i = 0; i < 8; i++) gdb_regs[GDB_L0 + i] = win->locals[i]; for (i = 0; i < 8; i++) gdb_regs[GDB_I0 + i] = win->ins[i]; for (i = GDB_F0; i <= GDB_F62; i++) gdb_regs[i] = 0; gdb_regs[GDB_PC] = regs->tpc; gdb_regs[GDB_NPC] = regs->tnpc; gdb_regs[GDB_STATE] = regs->tstate; gdb_regs[GDB_FSR] = 0; gdb_regs[GDB_FPRS] = 0; gdb_regs[GDB_Y] = regs->y; } void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) { struct thread_info *t = task_thread_info(p); extern unsigned int switch_to_pc; extern unsigned int ret_from_syscall; struct reg_window *win; unsigned long pc, cwp; int i; for (i = GDB_G0; i < GDB_G6; i++) gdb_regs[i] = 0; gdb_regs[GDB_G6] = (unsigned long) t; gdb_regs[GDB_G7] = (unsigned long) p; for (i = GDB_O0; i < GDB_SP; i++) gdb_regs[i] = 0; gdb_regs[GDB_SP] = t->ksp; gdb_regs[GDB_O7] = 0; win = (struct reg_window *) (t->ksp + STACK_BIAS); for (i = 0; i < 8; i++) gdb_regs[GDB_L0 + i] = win->locals[i]; for (i = 0; i < 8; i++) gdb_regs[GDB_I0 + i] = win->ins[i]; for (i = GDB_F0; i <= GDB_F62; i++) gdb_regs[i] = 0; if (t->new_child) pc = (unsigned long) &ret_from_syscall; else pc = (unsigned long) &switch_to_pc; gdb_regs[GDB_PC] = pc; gdb_regs[GDB_NPC] = pc + 4; cwp = __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP]; gdb_regs[GDB_STATE] = (TSTATE_PRIV | TSTATE_IE | cwp); gdb_regs[GDB_FSR] = 0; gdb_regs[GDB_FPRS] = 0; gdb_regs[GDB_Y] = 0; } void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs) { struct reg_window *win; int i; for (i = 0; i < 15; i++) regs->u_regs[UREG_G1 + i] = gdb_regs[GDB_G1 + i]; /* If the TSTATE register is changing, we have to preserve * the CWP field, otherwise window save/restore explodes. */ if (regs->tstate != gdb_regs[GDB_STATE]) { unsigned long cwp = regs->tstate & TSTATE_CWP; regs->tstate = (gdb_regs[GDB_STATE] & ~TSTATE_CWP) | cwp; } regs->tpc = gdb_regs[GDB_PC]; regs->tnpc = gdb_regs[GDB_NPC]; regs->y = gdb_regs[GDB_Y]; win = (struct reg_window *) (regs->u_regs[UREG_FP] + STACK_BIAS); for (i = 0; i < 8; i++) win->locals[i] = gdb_regs[GDB_L0 + i]; for (i = 0; i < 8; i++) win->ins[i] = gdb_regs[GDB_I0 + i]; } #ifdef CONFIG_SMP void __irq_entry smp_kgdb_capture_client(int irq, struct pt_regs *regs) { unsigned long flags; __asm__ __volatile__("rdpr %%pstate, %0\n\t" "wrpr %0, %1, %%pstate" : "=r" (flags) : "i" (PSTATE_IE)); flushw_all(); if (atomic_read(&kgdb_active) != -1) kgdb_nmicallback(raw_smp_processor_id(), regs); __asm__ __volatile__("wrpr %0, 0, %%pstate" : : "r" (flags)); } #endif 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; switch (remcomInBuffer[0]) { case 'c': /* try to read optional parameter, pc unchanged if no parm */ ptr = &remcomInBuffer[1]; if (kgdb_hex2long(&ptr, &addr)) { linux_regs->tpc = addr; linux_regs->tnpc = addr + 4; } /* fallthru */ case 'D': case 'k': if (linux_regs->tpc == (unsigned long) arch_kgdb_breakpoint) { linux_regs->tpc = linux_regs->tnpc; linux_regs->tnpc += 4; } return 0; } return -1; } asmlinkage void kgdb_trap(unsigned long trap_level, struct pt_regs *regs) { unsigned long flags; if (user_mode(regs)) { bad_trap(regs, trap_level); return; } flushw_all(); local_irq_save(flags); kgdb_handle_exception(0x172, SIGTRAP, 0, regs); local_irq_restore(flags); } int kgdb_arch_init(void) { return 0; } void kgdb_arch_exit(void) { } void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip) { regs->tpc = ip; regs->tnpc = regs->tpc + 4; } struct kgdb_arch arch_kgdb_ops = { /* Breakpoint instruction: ta 0x72 */ .gdb_bpt_instr = { 0x91, 0xd0, 0x20, 0x72 }, };