LXR linux/arch/sparc/kernel/kgdb

   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#include <linux/sched.h>
   9
  10#include <asm/kdebug.h>
  11#include <asm/ptrace.h>
  12#include <asm/irq.h>
  13#include <asm/cacheflush.h>
  14
  15#include "kernel.h"
  16#include "entry.h"
  17
  18void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
  19{
  20        struct reg_window32 *win;
  21        int i;
  22
  23        gdb_regs[GDB_G0] = 0;
  24        for (i = 0; i < 15; i++)
  25                gdb_regs[GDB_G1 + i] = regs->u_regs[UREG_G1 + i];
  26
  27        win = (struct reg_window32 *) regs->u_regs[UREG_FP];
  28        for (i = 0; i < 8; i++)
  29                gdb_regs[GDB_L0 + i] = win->locals[i];
  30        for (i = 0; i < 8; i++)
  31                gdb_regs[GDB_I0 + i] = win->ins[i];
  32
  33        for (i = GDB_F0; i <= GDB_F31; i++)
  34                gdb_regs[i] = 0;
  35
  36        gdb_regs[GDB_Y] = regs->y;
  37        gdb_regs[GDB_PSR] = regs->psr;
  38        gdb_regs[GDB_WIM] = 0;
  39        gdb_regs[GDB_TBR] = (unsigned long) &trapbase;
  40        gdb_regs[GDB_PC] = regs->pc;
  41        gdb_regs[GDB_NPC] = regs->npc;
  42        gdb_regs[GDB_FSR] = 0;
  43        gdb_regs[GDB_CSR] = 0;
  44}
  45
  46void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
  47{
  48        struct thread_info *t = task_thread_info(p);
  49        struct reg_window32 *win;
  50        int i;
  51
  52        for (i = GDB_G0; i < GDB_G6; i++)
  53                gdb_regs[i] = 0;
  54        gdb_regs[GDB_G6] = (unsigned long) t;
  55        gdb_regs[GDB_G7] = 0;
  56        for (i = GDB_O0; i < GDB_SP; i++)
  57                gdb_regs[i] = 0;
  58        gdb_regs[GDB_SP] = t->ksp;
  59        gdb_regs[GDB_O7] = 0;
  60
  61        win = (struct reg_window32 *) t->ksp;
  62        for (i = 0; i < 8; i++)
  63                gdb_regs[GDB_L0 + i] = win->locals[i];
  64        for (i = 0; i < 8; i++)
  65                gdb_regs[GDB_I0 + i] = win->ins[i];
  66
  67        for (i = GDB_F0; i <= GDB_F31; i++)
  68                gdb_regs[i] = 0;
  69
  70        gdb_regs[GDB_Y] = 0;
  71
  72        gdb_regs[GDB_PSR] = t->kpsr;
  73        gdb_regs[GDB_WIM] = t->kwim;
  74        gdb_regs[GDB_TBR] = (unsigned long) &trapbase;
  75        gdb_regs[GDB_PC] = t->kpc;
  76        gdb_regs[GDB_NPC] = t->kpc + 4;
  77        gdb_regs[GDB_FSR] = 0;
  78        gdb_regs[GDB_CSR] = 0;
  79}
  80
  81void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
  82{
  83        struct reg_window32 *win;
  84        int i;
  85
  86        for (i = 0; i < 15; i++)
  87                regs->u_regs[UREG_G1 + i] = gdb_regs[GDB_G1 + i];
  88
  89        /* If the PSR register is changing, we have to preserve
  90         * the CWP field, otherwise window save/restore explodes.
  91         */
  92        if (regs->psr != gdb_regs[GDB_PSR]) {
  93                unsigned long cwp = regs->psr & PSR_CWP;
  94
  95                regs->psr = (gdb_regs[GDB_PSR] & ~PSR_CWP) | cwp;
  96        }
  97
  98        regs->pc = gdb_regs[GDB_PC];
  99        regs->npc = gdb_regs[GDB_NPC];
 100        regs->y = gdb_regs[GDB_Y];
 101
 102        win = (struct reg_window32 *) regs->u_regs[UREG_FP];
 103        for (i = 0; i < 8; i++)
 104                win->locals[i] = gdb_regs[GDB_L0 + i];
 105        for (i = 0; i < 8; i++)
 106                win->ins[i] = gdb_regs[GDB_I0 + i];
 107}
 108
 109int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
 110                               char *remcomInBuffer, char *remcomOutBuffer,
 111                               struct pt_regs *linux_regs)
 112{
 113        unsigned long addr;
 114        char *ptr;
 115
 116        switch (remcomInBuffer[0]) {
 117        case 'c':
 118                /* try to read optional parameter, pc unchanged if no parm */
 119                ptr = &remcomInBuffer[1];
 120                if (kgdb_hex2long(&ptr, &addr)) {
 121                        linux_regs->pc = addr;
 122                        linux_regs->npc = addr + 4;
 123                }
 124                /* fallthru */
 125
 126        case 'D':
 127        case 'k':
 128                if (linux_regs->pc == (unsigned long) arch_kgdb_breakpoint) {
 129                        linux_regs->pc = linux_regs->npc;
 130                        linux_regs->npc += 4;
 131                }
 132                return 0;
 133        }
 134        return -1;
 135}
 136
 137asmlinkage void kgdb_trap(unsigned long trap_level, struct pt_regs *regs)
 138{
 139        unsigned long flags;
 140
 141        if (user_mode(regs)) {
 142                do_hw_interrupt(regs, trap_level);
 143                return;
 144        }
 145
 146        flushw_all();
 147
 148        local_irq_save(flags);
 149        kgdb_handle_exception(trap_level, SIGTRAP, 0, regs);
 150        local_irq_restore(flags);
 151}
 152
 153int kgdb_arch_init(void)
 154{
 155        return 0;
 156}
 157
 158void kgdb_arch_exit(void)
 159{
 160}
 161
 162void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
 163{
 164        regs->pc = ip;
 165        regs->npc = regs->pc + 4;
 166}
 167
 168struct kgdb_arch arch_kgdb_ops = {
 169        /* Breakpoint instruction: ta 0x7d */
 170        .gdb_bpt_instr          = { 0x91, 0xd0, 0x20, 0x7d },
 171};
 172