1/* kgdb.c: KGDB support for 32-bit sparc. 2 * 3 * Copyright (C) 2008 David S. Miller <davem@davemloft.net> 4 */ 5 6#include <linux/kgdb.h> 7#include <linux/kdebug.h> 8 9#include <asm/kdebug.h> 10#include <asm/ptrace.h> 11#include <asm/irq.h> 12 13extern unsigned long trapbase; 14 15void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) 16{ 17 struct reg_window32 *win; 18 int i; 19 20 gdb_regs[GDB_G0] = 0; 21 for (i = 0; i < 15; i++) 22 gdb_regs[GDB_G1 + i] = regs->u_regs[UREG_G1 + i]; 23 24 win = (struct reg_window32 *) regs->u_regs[UREG_FP]; 25 for (i = 0; i < 8; i++) 26 gdb_regs[GDB_L0 + i] = win->locals[i]; 27 for (i = 0; i < 8; i++) 28 gdb_regs[GDB_I0 + i] = win->ins[i]; 29 30 for (i = GDB_F0; i <= GDB_F31; i++) 31 gdb_regs[i] = 0; 32 33 gdb_regs[GDB_Y] = regs->y; 34 gdb_regs[GDB_PSR] = regs->psr; 35 gdb_regs[GDB_WIM] = 0; 36 gdb_regs[GDB_TBR] = (unsigned long) &trapbase; 37 gdb_regs[GDB_PC] = regs->pc; 38 gdb_regs[GDB_NPC] = regs->npc; 39 gdb_regs[GDB_FSR] = 0; 40 gdb_regs[GDB_CSR] = 0; 41} 42 43void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) 44{ 45 struct thread_info *t = task_thread_info(p); 46 struct reg_window32 *win; 47 int i; 48 49 for (i = GDB_G0; i < GDB_G6; i++) 50 gdb_regs[i] = 0; 51 gdb_regs[GDB_G6] = (unsigned long) t; 52 gdb_regs[GDB_G7] = 0; 53 for (i = GDB_O0; i < GDB_SP; i++) 54 gdb_regs[i] = 0; 55 gdb_regs[GDB_SP] = t->ksp; 56 gdb_regs[GDB_O7] = 0; 57 58 win = (struct reg_window32 *) t->ksp; 59 for (i = 0; i < 8; i++) 60 gdb_regs[GDB_L0 + i] = win->locals[i]; 61 for (i = 0; i < 8; i++) 62 gdb_regs[GDB_I0 + i] = win->ins[i]; 63 64 for (i = GDB_F0; i <= GDB_F31; i++) 65 gdb_regs[i] = 0; 66 67 gdb_regs[GDB_Y] = 0; 68 69 gdb_regs[GDB_PSR] = t->kpsr; 70 gdb_regs[GDB_WIM] = t->kwim; 71 gdb_regs[GDB_TBR] = (unsigned long) &trapbase; 72 gdb_regs[GDB_PC] = t->kpc; 73 gdb_regs[GDB_NPC] = t->kpc + 4; 74 gdb_regs[GDB_FSR] = 0; 75 gdb_regs[GDB_CSR] = 0; 76} 77 78void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs) 79{ 80 struct reg_window32 *win; 81 int i; 82 83 for (i = 0; i < 15; i++) 84 regs->u_regs[UREG_G1 + i] = gdb_regs[GDB_G1 + i]; 85 86 /* If the PSR register is changing, we have to preserve 87 * the CWP field, otherwise window save/restore explodes. 88 */ 89 if (regs->psr != gdb_regs[GDB_PSR]) { 90 unsigned long cwp = regs->psr & PSR_CWP; 91 92 regs->psr = (gdb_regs[GDB_PSR] & ~PSR_CWP) | cwp; 93 } 94 95 regs->pc = gdb_regs[GDB_PC]; 96 regs->npc = gdb_regs[GDB_NPC]; 97 regs->y = gdb_regs[GDB_Y]; 98 99 win = (struct reg_window32 *) regs->u_regs[UREG_FP]; 100 for (i = 0; i < 8; i++) 101 win->locals[i] = gdb_regs[GDB_L0 + i]; 102 for (i = 0; i < 8; i++) 103 win->ins[i] = gdb_regs[GDB_I0 + i]; 104} 105 106int kgdb_arch_handle_exception(int e_vector, int signo, int err_code, 107 char *remcomInBuffer, char *remcomOutBuffer, 108 struct pt_regs *linux_regs) 109{ 110 unsigned long addr; 111 char *ptr; 112 113 switch (remcomInBuffer[0]) { 114 case 'c': 115 /* try to read optional parameter, pc unchanged if no parm */ 116 ptr = &remcomInBuffer[1]; 117 if (kgdb_hex2long(&ptr, &addr)) { 118 linux_regs->pc = addr; 119 linux_regs->npc = addr + 4; 120 } 121 /* fallthru */ 122 123 case 'D': 124 case 'k': 125 if (linux_regs->pc == (unsigned long) arch_kgdb_breakpoint) { 126 linux_regs->pc = linux_regs->npc; 127 linux_regs->npc += 4; 128 } 129 return 0; 130 } 131 return -1; 132} 133 134extern void do_hw_interrupt(struct pt_regs *regs, unsigned long type); 135 136asmlinkage void kgdb_trap(struct pt_regs *regs) 137{ 138 unsigned long flags; 139 140 if (user_mode(regs)) { 141 do_hw_interrupt(regs, 0xfd); 142 return; 143 } 144 145 flushw_all(); 146 147 local_irq_save(flags); 148 kgdb_handle_exception(0x172, SIGTRAP, 0, regs); 149 local_irq_restore(flags); 150} 151 152int kgdb_arch_init(void) 153{ 154 return 0; 155} 156 157void kgdb_arch_exit(void) 158{ 159} 160 161void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip) 162{ 163 regs->pc = ip; 164 regs->npc = regs->pc + 4; 165} 166 167struct kgdb_arch arch_kgdb_ops = { 168 /* Breakpoint instruction: ta 0x7d */ 169 .gdb_bpt_instr = { 0x91, 0xd0, 0x20, 0x7d }, 170}; 171