/*
* Microblaze KGDB support
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/kgdb.h>
#include <linux/kdebug.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <asm/cacheflush.h>
#include <asm/asm-offsets.h>
#include <asm/kgdb.h>
#include <asm/pvr.h>
#define GDB_REG 0
#define GDB_PC 32
#define GDB_MSR 33
#define GDB_EAR 34
#define GDB_ESR 35
#define GDB_FSR 36
#define GDB_BTR 37
#define GDB_PVR 38
#define GDB_REDR 50
#define GDB_RPID 51
#define GDB_RZPR 52
#define GDB_RTLBX 53
#define GDB_RTLBSX 54 /* mfs can't read it */
#define GDB_RTLBLO 55
#define GDB_RTLBHI 56
/* keep pvr separately because it is unchangeable */
static struct pvr_s pvr;
void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
unsigned int i;
unsigned long *pt_regb = (unsigned long *)regs;
int temp;
/* registers r0 - r31, pc, msr, ear, esr, fsr + do not save pt_mode */
for (i = 0; i < (sizeof(struct pt_regs) / 4) - 1; i++)
gdb_regs[i] = pt_regb[i];
/* Branch target register can't be changed */
__asm__ __volatile__ ("mfs %0, rbtr;" : "=r"(temp) : );
gdb_regs[GDB_BTR] = temp;
/* pvr part - we have 11 pvr regs */
for (i = 0; i < sizeof(struct pvr_s)/4; i++)
gdb_regs[GDB_PVR + i] = pvr.pvr[i];
/* read special registers - can't be changed */
__asm__ __volatile__ ("mfs %0, redr;" : "=r"(temp) : );
gdb_regs[GDB_REDR] = temp;
__asm__ __volatile__ ("mfs %0, rpid;" : "=r"(temp) : );
gdb_regs[GDB_RPID] = temp;
__asm__ __volatile__ ("mfs %0, rzpr;" : "=r"(temp) : );
gdb_regs[GDB_RZPR] = temp;
__asm__ __volatile__ ("mfs %0, rtlbx;" : "=r"(temp) : );
gdb_regs[GDB_RTLBX] = temp;
__asm__ __volatile__ ("mfs %0, rtlblo;" : "=r"(temp) : );
gdb_regs[GDB_RTLBLO] = temp;
__asm__ __volatile__ ("mfs %0, rtlbhi;" : "=r"(temp) : );
gdb_regs[GDB_RTLBHI] = temp;
}
void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
unsigned int i;
unsigned long *pt_regb = (unsigned long *)regs;
/* pt_regs and gdb_regs have the same 37 values.
* The rest of gdb_regs are unused and can't be changed.
* r0 register value can't be changed too. */
for (i = 1; i < (sizeof(struct pt_regs) / 4) - 1; i++)
pt_regb[i] = gdb_regs[i];
}
asmlinkage void microblaze_kgdb_break(struct pt_regs *regs)
{
if (kgdb_handle_exception(1, SIGTRAP, 0, regs) != 0)
return;
/* Jump over the first arch_kgdb_breakpoint which is barrier to
* get kgdb work. The same solution is used for powerpc */
if (*(u32 *) (regs->pc) == *(u32 *) (&arch_kgdb_ops.gdb_bpt_instr))
regs->pc += BREAK_INSTR_SIZE;
}
/* untested */
void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
{
unsigned int i;
unsigned long *pt_regb = (unsigned long *)(p->thread.regs);
/* registers r0 - r31, pc, msr, ear, esr, fsr + do not save pt_mode */
for (i = 0; i < (sizeof(struct pt_regs) / 4) - 1; i++)
gdb_regs[i] = pt_regb[i];
/* pvr part - we have 11 pvr regs */
for (i = 0; i < sizeof(struct pvr_s)/4; i++)
gdb_regs[GDB_PVR + i] = pvr.pvr[i];
}
void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
{
regs->pc = ip;
}
int kgdb_arch_handle_exception(int vector, int signo, int err_code,
char *remcom_in_buffer, char *remcom_out_buffer,
struct pt_regs *regs)
{
char *ptr;
unsigned long address;
switch (remcom_in_buffer[0]) {
case 'c':
/* handle the optional parameter */
ptr = &remcom_in_buffer[1];
if (kgdb_hex2long(&ptr, &address))
regs->pc = address;
return 0;
}
return -1; /* this means that we do not want to exit from the handler */
}
int kgdb_arch_init(void)
{
get_pvr(&pvr); /* Fill PVR structure */
return 0;
}
void kgdb_arch_exit(void)
{
/* Nothing to do */
}
/*
* Global data
*/
const struct kgdb_arch arch_kgdb_ops = {
#ifdef __MICROBLAZEEL__
.gdb_bpt_instr = {0x18, 0x00, 0x0c, 0xba}, /* brki r16, 0x18 */
#else
.gdb_bpt_instr = {0xba, 0x0c, 0x00, 0x18}, /* brki r16, 0x18 */
#endif
};
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