linux/arch/blackfin/kernel/kgdb.c
Mike Frysinger e56e03b0cf Blackfin: unify memory region checks between kgdb and traps
The kgdb (in multiple places) and traps code developed pretty much
identical checks for how to access different regions of the Blackfin
memory map, but each wasn't 100%, so unify them to avoid duplication,
bitrot, and bugs with edge cases.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-22 21:15:34 -04:00

675 lines
17 KiB
C

/*
* arch/blackfin/kernel/kgdb.c - Blackfin kgdb pieces
*
* Copyright 2005-2008 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/ptrace.h> /* for linux pt_regs struct */
#include <linux/kgdb.h>
#include <linux/console.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/irq.h>
#include <linux/uaccess.h>
#include <asm/system.h>
#include <asm/traps.h>
#include <asm/blackfin.h>
#include <asm/dma.h>
/* Put the error code here just in case the user cares. */
int gdb_bfin_errcode;
/* Likewise, the vector number here (since GDB only gets the signal
number through the usual means, and that's not very specific). */
int gdb_bfin_vector = -1;
#if KGDB_MAX_NO_CPUS != 8
#error change the definition of slavecpulocks
#endif
void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
gdb_regs[BFIN_R0] = regs->r0;
gdb_regs[BFIN_R1] = regs->r1;
gdb_regs[BFIN_R2] = regs->r2;
gdb_regs[BFIN_R3] = regs->r3;
gdb_regs[BFIN_R4] = regs->r4;
gdb_regs[BFIN_R5] = regs->r5;
gdb_regs[BFIN_R6] = regs->r6;
gdb_regs[BFIN_R7] = regs->r7;
gdb_regs[BFIN_P0] = regs->p0;
gdb_regs[BFIN_P1] = regs->p1;
gdb_regs[BFIN_P2] = regs->p2;
gdb_regs[BFIN_P3] = regs->p3;
gdb_regs[BFIN_P4] = regs->p4;
gdb_regs[BFIN_P5] = regs->p5;
gdb_regs[BFIN_SP] = regs->reserved;
gdb_regs[BFIN_FP] = regs->fp;
gdb_regs[BFIN_I0] = regs->i0;
gdb_regs[BFIN_I1] = regs->i1;
gdb_regs[BFIN_I2] = regs->i2;
gdb_regs[BFIN_I3] = regs->i3;
gdb_regs[BFIN_M0] = regs->m0;
gdb_regs[BFIN_M1] = regs->m1;
gdb_regs[BFIN_M2] = regs->m2;
gdb_regs[BFIN_M3] = regs->m3;
gdb_regs[BFIN_B0] = regs->b0;
gdb_regs[BFIN_B1] = regs->b1;
gdb_regs[BFIN_B2] = regs->b2;
gdb_regs[BFIN_B3] = regs->b3;
gdb_regs[BFIN_L0] = regs->l0;
gdb_regs[BFIN_L1] = regs->l1;
gdb_regs[BFIN_L2] = regs->l2;
gdb_regs[BFIN_L3] = regs->l3;
gdb_regs[BFIN_A0_DOT_X] = regs->a0x;
gdb_regs[BFIN_A0_DOT_W] = regs->a0w;
gdb_regs[BFIN_A1_DOT_X] = regs->a1x;
gdb_regs[BFIN_A1_DOT_W] = regs->a1w;
gdb_regs[BFIN_ASTAT] = regs->astat;
gdb_regs[BFIN_RETS] = regs->rets;
gdb_regs[BFIN_LC0] = regs->lc0;
gdb_regs[BFIN_LT0] = regs->lt0;
gdb_regs[BFIN_LB0] = regs->lb0;
gdb_regs[BFIN_LC1] = regs->lc1;
gdb_regs[BFIN_LT1] = regs->lt1;
gdb_regs[BFIN_LB1] = regs->lb1;
gdb_regs[BFIN_CYCLES] = 0;
gdb_regs[BFIN_CYCLES2] = 0;
gdb_regs[BFIN_USP] = regs->usp;
gdb_regs[BFIN_SEQSTAT] = regs->seqstat;
gdb_regs[BFIN_SYSCFG] = regs->syscfg;
gdb_regs[BFIN_RETI] = regs->pc;
gdb_regs[BFIN_RETX] = regs->retx;
gdb_regs[BFIN_RETN] = regs->retn;
gdb_regs[BFIN_RETE] = regs->rete;
gdb_regs[BFIN_PC] = regs->pc;
gdb_regs[BFIN_CC] = 0;
gdb_regs[BFIN_EXTRA1] = 0;
gdb_regs[BFIN_EXTRA2] = 0;
gdb_regs[BFIN_EXTRA3] = 0;
gdb_regs[BFIN_IPEND] = regs->ipend;
}
/*
* Extracts ebp, esp and eip values understandable by gdb from the values
* saved by switch_to.
* thread.esp points to ebp. flags and ebp are pushed in switch_to hence esp
* prior to entering switch_to is 8 greater than the value that is saved.
* If switch_to changes, change following code appropriately.
*/
void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
{
gdb_regs[BFIN_SP] = p->thread.ksp;
gdb_regs[BFIN_PC] = p->thread.pc;
gdb_regs[BFIN_SEQSTAT] = p->thread.seqstat;
}
void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
regs->r0 = gdb_regs[BFIN_R0];
regs->r1 = gdb_regs[BFIN_R1];
regs->r2 = gdb_regs[BFIN_R2];
regs->r3 = gdb_regs[BFIN_R3];
regs->r4 = gdb_regs[BFIN_R4];
regs->r5 = gdb_regs[BFIN_R5];
regs->r6 = gdb_regs[BFIN_R6];
regs->r7 = gdb_regs[BFIN_R7];
regs->p0 = gdb_regs[BFIN_P0];
regs->p1 = gdb_regs[BFIN_P1];
regs->p2 = gdb_regs[BFIN_P2];
regs->p3 = gdb_regs[BFIN_P3];
regs->p4 = gdb_regs[BFIN_P4];
regs->p5 = gdb_regs[BFIN_P5];
regs->fp = gdb_regs[BFIN_FP];
regs->i0 = gdb_regs[BFIN_I0];
regs->i1 = gdb_regs[BFIN_I1];
regs->i2 = gdb_regs[BFIN_I2];
regs->i3 = gdb_regs[BFIN_I3];
regs->m0 = gdb_regs[BFIN_M0];
regs->m1 = gdb_regs[BFIN_M1];
regs->m2 = gdb_regs[BFIN_M2];
regs->m3 = gdb_regs[BFIN_M3];
regs->b0 = gdb_regs[BFIN_B0];
regs->b1 = gdb_regs[BFIN_B1];
regs->b2 = gdb_regs[BFIN_B2];
regs->b3 = gdb_regs[BFIN_B3];
regs->l0 = gdb_regs[BFIN_L0];
regs->l1 = gdb_regs[BFIN_L1];
regs->l2 = gdb_regs[BFIN_L2];
regs->l3 = gdb_regs[BFIN_L3];
regs->a0x = gdb_regs[BFIN_A0_DOT_X];
regs->a0w = gdb_regs[BFIN_A0_DOT_W];
regs->a1x = gdb_regs[BFIN_A1_DOT_X];
regs->a1w = gdb_regs[BFIN_A1_DOT_W];
regs->rets = gdb_regs[BFIN_RETS];
regs->lc0 = gdb_regs[BFIN_LC0];
regs->lt0 = gdb_regs[BFIN_LT0];
regs->lb0 = gdb_regs[BFIN_LB0];
regs->lc1 = gdb_regs[BFIN_LC1];
regs->lt1 = gdb_regs[BFIN_LT1];
regs->lb1 = gdb_regs[BFIN_LB1];
regs->usp = gdb_regs[BFIN_USP];
regs->syscfg = gdb_regs[BFIN_SYSCFG];
regs->retx = gdb_regs[BFIN_PC];
regs->retn = gdb_regs[BFIN_RETN];
regs->rete = gdb_regs[BFIN_RETE];
regs->pc = gdb_regs[BFIN_PC];
#if 0 /* can't change these */
regs->astat = gdb_regs[BFIN_ASTAT];
regs->seqstat = gdb_regs[BFIN_SEQSTAT];
regs->ipend = gdb_regs[BFIN_IPEND];
#endif
}
struct hw_breakpoint {
unsigned int occupied:1;
unsigned int skip:1;
unsigned int enabled:1;
unsigned int type:1;
unsigned int dataacc:2;
unsigned short count;
unsigned int addr;
} breakinfo[HW_WATCHPOINT_NUM];
int bfin_set_hw_break(unsigned long addr, int len, enum kgdb_bptype type)
{
int breakno;
int bfin_type;
int dataacc = 0;
switch (type) {
case BP_HARDWARE_BREAKPOINT:
bfin_type = TYPE_INST_WATCHPOINT;
break;
case BP_WRITE_WATCHPOINT:
dataacc = 1;
bfin_type = TYPE_DATA_WATCHPOINT;
break;
case BP_READ_WATCHPOINT:
dataacc = 2;
bfin_type = TYPE_DATA_WATCHPOINT;
break;
case BP_ACCESS_WATCHPOINT:
dataacc = 3;
bfin_type = TYPE_DATA_WATCHPOINT;
break;
default:
return -ENOSPC;
}
/* Becasue hardware data watchpoint impelemented in current
* Blackfin can not trigger an exception event as the hardware
* instrction watchpoint does, we ignaore all data watch point here.
* They can be turned on easily after future blackfin design
* supports this feature.
*/
for (breakno = 0; breakno < HW_INST_WATCHPOINT_NUM; breakno++)
if (bfin_type == breakinfo[breakno].type
&& !breakinfo[breakno].occupied) {
breakinfo[breakno].occupied = 1;
breakinfo[breakno].skip = 0;
breakinfo[breakno].enabled = 1;
breakinfo[breakno].addr = addr;
breakinfo[breakno].dataacc = dataacc;
breakinfo[breakno].count = 0;
return 0;
}
return -ENOSPC;
}
int bfin_remove_hw_break(unsigned long addr, int len, enum kgdb_bptype type)
{
int breakno;
int bfin_type;
switch (type) {
case BP_HARDWARE_BREAKPOINT:
bfin_type = TYPE_INST_WATCHPOINT;
break;
case BP_WRITE_WATCHPOINT:
case BP_READ_WATCHPOINT:
case BP_ACCESS_WATCHPOINT:
bfin_type = TYPE_DATA_WATCHPOINT;
break;
default:
return 0;
}
for (breakno = 0; breakno < HW_WATCHPOINT_NUM; breakno++)
if (bfin_type == breakinfo[breakno].type
&& breakinfo[breakno].occupied
&& breakinfo[breakno].addr == addr) {
breakinfo[breakno].occupied = 0;
breakinfo[breakno].enabled = 0;
}
return 0;
}
void bfin_remove_all_hw_break(void)
{
int breakno;
memset(breakinfo, 0, sizeof(struct hw_breakpoint)*HW_WATCHPOINT_NUM);
for (breakno = 0; breakno < HW_INST_WATCHPOINT_NUM; breakno++)
breakinfo[breakno].type = TYPE_INST_WATCHPOINT;
for (; breakno < HW_WATCHPOINT_NUM; breakno++)
breakinfo[breakno].type = TYPE_DATA_WATCHPOINT;
}
void bfin_correct_hw_break(void)
{
int breakno;
unsigned int wpiactl = 0;
unsigned int wpdactl = 0;
int enable_wp = 0;
for (breakno = 0; breakno < HW_WATCHPOINT_NUM; breakno++)
if (breakinfo[breakno].enabled) {
enable_wp = 1;
switch (breakno) {
case 0:
wpiactl |= WPIAEN0|WPICNTEN0;
bfin_write_WPIA0(breakinfo[breakno].addr);
bfin_write_WPIACNT0(breakinfo[breakno].count
+ breakinfo->skip);
break;
case 1:
wpiactl |= WPIAEN1|WPICNTEN1;
bfin_write_WPIA1(breakinfo[breakno].addr);
bfin_write_WPIACNT1(breakinfo[breakno].count
+ breakinfo->skip);
break;
case 2:
wpiactl |= WPIAEN2|WPICNTEN2;
bfin_write_WPIA2(breakinfo[breakno].addr);
bfin_write_WPIACNT2(breakinfo[breakno].count
+ breakinfo->skip);
break;
case 3:
wpiactl |= WPIAEN3|WPICNTEN3;
bfin_write_WPIA3(breakinfo[breakno].addr);
bfin_write_WPIACNT3(breakinfo[breakno].count
+ breakinfo->skip);
break;
case 4:
wpiactl |= WPIAEN4|WPICNTEN4;
bfin_write_WPIA4(breakinfo[breakno].addr);
bfin_write_WPIACNT4(breakinfo[breakno].count
+ breakinfo->skip);
break;
case 5:
wpiactl |= WPIAEN5|WPICNTEN5;
bfin_write_WPIA5(breakinfo[breakno].addr);
bfin_write_WPIACNT5(breakinfo[breakno].count
+ breakinfo->skip);
break;
case 6:
wpdactl |= WPDAEN0|WPDCNTEN0|WPDSRC0;
wpdactl |= breakinfo[breakno].dataacc
<< WPDACC0_OFFSET;
bfin_write_WPDA0(breakinfo[breakno].addr);
bfin_write_WPDACNT0(breakinfo[breakno].count
+ breakinfo->skip);
break;
case 7:
wpdactl |= WPDAEN1|WPDCNTEN1|WPDSRC1;
wpdactl |= breakinfo[breakno].dataacc
<< WPDACC1_OFFSET;
bfin_write_WPDA1(breakinfo[breakno].addr);
bfin_write_WPDACNT1(breakinfo[breakno].count
+ breakinfo->skip);
break;
}
}
/* Should enable WPPWR bit first before set any other
* WPIACTL and WPDACTL bits */
if (enable_wp) {
bfin_write_WPIACTL(WPPWR);
CSYNC();
bfin_write_WPIACTL(wpiactl|WPPWR);
bfin_write_WPDACTL(wpdactl);
CSYNC();
}
}
void kgdb_disable_hw_debug(struct pt_regs *regs)
{
/* Disable hardware debugging while we are in kgdb */
bfin_write_WPIACTL(0);
bfin_write_WPDACTL(0);
CSYNC();
}
#ifdef CONFIG_SMP
void kgdb_passive_cpu_callback(void *info)
{
kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs());
}
void kgdb_roundup_cpus(unsigned long flags)
{
smp_call_function(kgdb_passive_cpu_callback, NULL, 0);
}
void kgdb_roundup_cpu(int cpu, unsigned long flags)
{
smp_call_function_single(cpu, kgdb_passive_cpu_callback, NULL, 0);
}
#endif
void kgdb_post_primary_code(struct pt_regs *regs, int eVector, int err_code)
{
/* Master processor is completely in the debugger */
gdb_bfin_vector = eVector;
gdb_bfin_errcode = err_code;
}
int kgdb_arch_handle_exception(int vector, int signo,
int err_code, char *remcom_in_buffer,
char *remcom_out_buffer,
struct pt_regs *regs)
{
long addr;
char *ptr;
int newPC;
int i;
switch (remcom_in_buffer[0]) {
case 'c':
case 's':
if (kgdb_contthread && kgdb_contthread != current) {
strcpy(remcom_out_buffer, "E00");
break;
}
kgdb_contthread = NULL;
/* try to read optional parameter, pc unchanged if no parm */
ptr = &remcom_in_buffer[1];
if (kgdb_hex2long(&ptr, &addr)) {
regs->retx = addr;
}
newPC = regs->retx;
/* clear the trace bit */
regs->syscfg &= 0xfffffffe;
/* set the trace bit if we're stepping */
if (remcom_in_buffer[0] == 's') {
regs->syscfg |= 0x1;
kgdb_single_step = regs->ipend;
kgdb_single_step >>= 6;
for (i = 10; i > 0; i--, kgdb_single_step >>= 1)
if (kgdb_single_step & 1)
break;
/* i indicate event priority of current stopped instruction
* user space instruction is 0, IVG15 is 1, IVTMR is 10.
* kgdb_single_step > 0 means in single step mode
*/
kgdb_single_step = i + 1;
}
bfin_correct_hw_break();
return 0;
} /* switch */
return -1; /* this means that we do not want to exit from the handler */
}
struct kgdb_arch arch_kgdb_ops = {
.gdb_bpt_instr = {0xa1},
#ifdef CONFIG_SMP
.flags = KGDB_HW_BREAKPOINT|KGDB_THR_PROC_SWAP,
#else
.flags = KGDB_HW_BREAKPOINT,
#endif
.set_hw_breakpoint = bfin_set_hw_break,
.remove_hw_breakpoint = bfin_remove_hw_break,
.remove_all_hw_break = bfin_remove_all_hw_break,
.correct_hw_break = bfin_correct_hw_break,
};
static int hex(char ch)
{
if ((ch >= 'a') && (ch <= 'f'))
return ch - 'a' + 10;
if ((ch >= '0') && (ch <= '9'))
return ch - '0';
if ((ch >= 'A') && (ch <= 'F'))
return ch - 'A' + 10;
return -1;
}
static int validate_memory_access_address(unsigned long addr, int size)
{
if (size < 0 || addr == 0)
return -EFAULT;
return bfin_mem_access_type(addr, size);
}
static int bfin_probe_kernel_read(char *dst, char *src, int size)
{
unsigned long lsrc = (unsigned long)src;
int mem_type;
mem_type = validate_memory_access_address(lsrc, size);
if (mem_type < 0)
return mem_type;
if (lsrc >= SYSMMR_BASE) {
if (size == 2 && lsrc % 2 == 0) {
u16 mmr = bfin_read16(src);
memcpy(dst, &mmr, sizeof(mmr));
return 0;
} else if (size == 4 && lsrc % 4 == 0) {
u32 mmr = bfin_read32(src);
memcpy(dst, &mmr, sizeof(mmr));
return 0;
}
} else {
switch (mem_type) {
case BFIN_MEM_ACCESS_CORE:
case BFIN_MEM_ACCESS_CORE_ONLY:
return probe_kernel_read(dst, src, size);
/* XXX: should support IDMA here with SMP */
case BFIN_MEM_ACCESS_DMA:
if (dma_memcpy(dst, src, size))
return 0;
break;
case BFIN_MEM_ACCESS_ITEST:
if (isram_memcpy(dst, src, size))
return 0;
break;
}
}
return -EFAULT;
}
static int bfin_probe_kernel_write(char *dst, char *src, int size)
{
unsigned long ldst = (unsigned long)dst;
int mem_type;
mem_type = validate_memory_access_address(ldst, size);
if (mem_type < 0)
return mem_type;
if (ldst >= SYSMMR_BASE) {
if (size == 2 && ldst % 2 == 0) {
u16 mmr;
memcpy(&mmr, src, sizeof(mmr));
bfin_write16(dst, mmr);
return 0;
} else if (size == 4 && ldst % 4 == 0) {
u32 mmr;
memcpy(&mmr, src, sizeof(mmr));
bfin_write32(dst, mmr);
return 0;
}
} else {
switch (mem_type) {
case BFIN_MEM_ACCESS_CORE:
case BFIN_MEM_ACCESS_CORE_ONLY:
return probe_kernel_write(dst, src, size);
/* XXX: should support IDMA here with SMP */
case BFIN_MEM_ACCESS_DMA:
if (dma_memcpy(dst, src, size))
return 0;
break;
case BFIN_MEM_ACCESS_ITEST:
if (isram_memcpy(dst, src, size))
return 0;
break;
}
}
return -EFAULT;
}
/*
* Convert the memory pointed to by mem into hex, placing result in buf.
* Return a pointer to the last char put in buf (null). May return an error.
*/
int kgdb_mem2hex(char *mem, char *buf, int count)
{
char *tmp;
int err;
/*
* We use the upper half of buf as an intermediate buffer for the
* raw memory copy. Hex conversion will work against this one.
*/
tmp = buf + count;
err = bfin_probe_kernel_read(tmp, mem, count);
if (!err) {
while (count > 0) {
buf = pack_hex_byte(buf, *tmp);
tmp++;
count--;
}
*buf = 0;
}
return err;
}
/*
* Copy the binary array pointed to by buf into mem. Fix $, #, and
* 0x7d escaped with 0x7d. Return a pointer to the character after
* the last byte written.
*/
int kgdb_ebin2mem(char *buf, char *mem, int count)
{
char *tmp_old, *tmp_new;
int size;
tmp_old = tmp_new = buf;
for (size = 0; size < count; ++size) {
if (*tmp_old == 0x7d)
*tmp_new = *(++tmp_old) ^ 0x20;
else
*tmp_new = *tmp_old;
tmp_new++;
tmp_old++;
}
return bfin_probe_kernel_write(mem, buf, count);
}
/*
* Convert the hex array pointed to by buf into binary to be placed in mem.
* Return a pointer to the character AFTER the last byte written.
* May return an error.
*/
int kgdb_hex2mem(char *buf, char *mem, int count)
{
char *tmp_raw, *tmp_hex;
/*
* We use the upper half of buf as an intermediate buffer for the
* raw memory that is converted from hex.
*/
tmp_raw = buf + count * 2;
tmp_hex = tmp_raw - 1;
while (tmp_hex >= buf) {
tmp_raw--;
*tmp_raw = hex(*tmp_hex--);
*tmp_raw |= hex(*tmp_hex--) << 4;
}
return bfin_probe_kernel_write(mem, tmp_raw, count);
}
#define IN_MEM(addr, size, l1_addr, l1_size) \
({ \
unsigned long __addr = (unsigned long)(addr); \
(l1_size && __addr >= l1_addr && __addr + (size) <= l1_addr + l1_size); \
})
#define ASYNC_BANK_SIZE \
(ASYNC_BANK0_SIZE + ASYNC_BANK1_SIZE + \
ASYNC_BANK2_SIZE + ASYNC_BANK3_SIZE)
int kgdb_validate_break_address(unsigned long addr)
{
int cpu = raw_smp_processor_id();
if (addr >= 0x1000 && (addr + BREAK_INSTR_SIZE) <= physical_mem_end)
return 0;
if (IN_MEM(addr, BREAK_INSTR_SIZE, ASYNC_BANK0_BASE, ASYNC_BANK_SIZE))
return 0;
if (cpu == 0 && IN_MEM(addr, BREAK_INSTR_SIZE, L1_CODE_START, L1_CODE_LENGTH))
return 0;
#ifdef CONFIG_SMP
else if (cpu == 1 && IN_MEM(addr, BREAK_INSTR_SIZE, COREB_L1_CODE_START, L1_CODE_LENGTH))
return 0;
#endif
if (IN_MEM(addr, BREAK_INSTR_SIZE, L2_START, L2_LENGTH))
return 0;
return -EFAULT;
}
int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr)
{
int err = bfin_probe_kernel_read(saved_instr, (char *)addr,
BREAK_INSTR_SIZE);
if (err)
return err;
return bfin_probe_kernel_write((char *)addr, arch_kgdb_ops.gdb_bpt_instr,
BREAK_INSTR_SIZE);
}
int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle)
{
return bfin_probe_kernel_write((char *)addr, bundle, BREAK_INSTR_SIZE);
}
int kgdb_arch_init(void)
{
kgdb_single_step = 0;
bfin_remove_all_hw_break();
return 0;
}
void kgdb_arch_exit(void)
{
}