blob: 23752f3940bc06e1ad5776da0f2a4ca6ce0ffeaa [file] [log] [blame]
/*
* Bedbug Functions specific to the PPC405 chip
*/
#include <common.h>
#include <command.h>
#include <linux/ctype.h>
#include <bedbug/type.h>
#include <bedbug/bedbug.h>
#include <bedbug/regs.h>
#include <bedbug/ppc.h>
#if (CONFIG_COMMANDS & CFG_CMD_BEDBUG) && defined(CONFIG_4xx)
#define MAX_BREAK_POINTS 4
extern CPU_DEBUG_CTX bug_ctx;
void bedbug405_init __P ((void));
void bedbug405_do_break __P ((cmd_tbl_t *, int, int, char *[]));
void bedbug405_break_isr __P ((struct pt_regs *));
int bedbug405_find_empty __P ((void));
int bedbug405_set __P ((int, unsigned long));
int bedbug405_clear __P ((int));
/* ======================================================================
* Initialize the global bug_ctx structure for the IBM PPC405. Clear all
* of the breakpoints.
* ====================================================================== */
void bedbug405_init (void)
{
int i;
/* -------------------------------------------------- */
bug_ctx.hw_debug_enabled = 0;
bug_ctx.stopped = 0;
bug_ctx.current_bp = 0;
bug_ctx.regs = NULL;
bug_ctx.do_break = bedbug405_do_break;
bug_ctx.break_isr = bedbug405_break_isr;
bug_ctx.find_empty = bedbug405_find_empty;
bug_ctx.set = bedbug405_set;
bug_ctx.clear = bedbug405_clear;
for (i = 1; i <= MAX_BREAK_POINTS; ++i)
(*bug_ctx.clear) (i);
puts ("BEDBUG:ready\n");
return;
} /* bedbug_init_breakpoints */
/* ======================================================================
* Set/clear/show one of the hardware breakpoints for the 405. The "off"
* string will disable a specific breakpoint. The "show" string will
* display the current breakpoints. Otherwise an address will set a
* breakpoint at that address. Setting a breakpoint uses the CPU-specific
* set routine which will assign a breakpoint number.
* ====================================================================== */
void bedbug405_do_break (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
{
long addr = 0; /* Address to break at */
int which_bp; /* Breakpoint number */
/* -------------------------------------------------- */
if (argc < 2) {
printf ("Usage:\n%s\n", cmdtp->usage);
return;
}
/* Turn off a breakpoint */
if (strcmp (argv[1], "off") == 0) {
if (bug_ctx.hw_debug_enabled == 0) {
printf ("No breakpoints enabled\n");
return;
}
which_bp = simple_strtoul (argv[2], NULL, 10);
if (bug_ctx.clear)
(*bug_ctx.clear) (which_bp);
printf ("Breakpoint %d removed\n", which_bp);
return;
}
/* Show a list of breakpoints */
if (strcmp (argv[1], "show") == 0) {
for (which_bp = 1; which_bp <= MAX_BREAK_POINTS; ++which_bp) {
switch (which_bp) {
case 1:
addr = GET_IAC1 ();
break;
case 2:
addr = GET_IAC2 ();
break;
case 3:
addr = GET_IAC3 ();
break;
case 4:
addr = GET_IAC4 ();
break;
}
printf ("Breakpoint [%d]: ", which_bp);
if (addr == 0)
printf ("NOT SET\n");
else
disppc ((unsigned char *) addr, 0, 1, bedbug_puts,
F_RADHEX);
}
return;
}
/* Set a breakpoint at the address */
if (!isdigit (argv[1][0])) {
printf ("Usage:\n%s\n", cmdtp->usage);
return;
}
addr = simple_strtoul (argv[1], NULL, 16) & 0xfffffffc;
if ((bug_ctx.set) && (which_bp = (*bug_ctx.set) (0, addr)) > 0) {
printf ("Breakpoint [%d]: ", which_bp);
disppc ((unsigned char *) addr, 0, 1, bedbug_puts, F_RADHEX);
}
return;
} /* bedbug405_do_break */
/* ======================================================================
* Handle a breakpoint. First determine which breakpoint was hit by
* looking at the DeBug Status Register (DBSR), clear the breakpoint
* and enter a mini main loop. Stay in the loop until the stopped flag
* in the debug context is cleared.
* ====================================================================== */
void bedbug405_break_isr (struct pt_regs *regs)
{
unsigned long dbsr_val; /* Value of the DBSR */
unsigned long addr = 0; /* Address stopped at */
/* -------------------------------------------------- */
dbsr_val = GET_DBSR ();
if (dbsr_val & DBSR_IA1) {
bug_ctx.current_bp = 1;
addr = GET_IAC1 ();
SET_DBSR (DBSR_IA1); /* Write a 1 to clear */
} else if (dbsr_val & DBSR_IA2) {
bug_ctx.current_bp = 2;
addr = GET_IAC2 ();
SET_DBSR (DBSR_IA2); /* Write a 1 to clear */
} else if (dbsr_val & DBSR_IA3) {
bug_ctx.current_bp = 3;
addr = GET_IAC3 ();
SET_DBSR (DBSR_IA3); /* Write a 1 to clear */
} else if (dbsr_val & DBSR_IA4) {
bug_ctx.current_bp = 4;
addr = GET_IAC4 ();
SET_DBSR (DBSR_IA4); /* Write a 1 to clear */
}
bedbug_main_loop (addr, regs);
return;
} /* bedbug405_break_isr */
/* ======================================================================
* Look through all of the hardware breakpoints available to see if one
* is unused.
* ====================================================================== */
int bedbug405_find_empty (void)
{
/* -------------------------------------------------- */
if (GET_IAC1 () == 0)
return 1;
if (GET_IAC2 () == 0)
return 2;
if (GET_IAC3 () == 0)
return 3;
if (GET_IAC4 () == 0)
return 4;
return 0;
} /* bedbug405_find_empty */
/* ======================================================================
* Set a breakpoint. If 'which_bp' is zero then find an unused breakpoint
* number, otherwise reassign the given breakpoint. If hardware debugging
* is not enabled, then turn it on via the MSR and DBCR0. Set the break
* address in the appropriate IACx register and enable proper address
* beakpoint in DBCR0.
* ====================================================================== */
int bedbug405_set (int which_bp, unsigned long addr)
{
/* -------------------------------------------------- */
/* Only look if which_bp == 0, else use which_bp */
if ((bug_ctx.find_empty) && (!which_bp) &&
(which_bp = (*bug_ctx.find_empty) ()) == 0) {
printf ("All breakpoints in use\n");
return 0;
}
if (which_bp < 1 || which_bp > MAX_BREAK_POINTS) {
printf ("Invalid break point # %d\n", which_bp);
return 0;
}
if (!bug_ctx.hw_debug_enabled) {
SET_MSR (GET_MSR () | 0x200); /* set MSR[ DE ] */
SET_DBCR0 (GET_DBCR0 () | DBCR0_IDM);
bug_ctx.hw_debug_enabled = 1;
}
switch (which_bp) {
case 1:
SET_IAC1 (addr);
SET_DBCR0 (GET_DBCR0 () | DBCR0_IA1);
break;
case 2:
SET_IAC2 (addr);
SET_DBCR0 (GET_DBCR0 () | DBCR0_IA2);
break;
case 3:
SET_IAC3 (addr);
SET_DBCR0 (GET_DBCR0 () | DBCR0_IA3);
break;
case 4:
SET_IAC4 (addr);
SET_DBCR0 (GET_DBCR0 () | DBCR0_IA4);
break;
}
return which_bp;
} /* bedbug405_set */
/* ======================================================================
* Disable a specific breakoint by setting the appropriate IACx register
* to zero and claring the instruction address breakpoint in DBCR0.
* ====================================================================== */
int bedbug405_clear (int which_bp)
{
/* -------------------------------------------------- */
if (which_bp < 1 || which_bp > MAX_BREAK_POINTS) {
printf ("Invalid break point # (%d)\n", which_bp);
return -1;
}
switch (which_bp) {
case 1:
SET_IAC1 (0);
SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA1);
break;
case 2:
SET_IAC2 (0);
SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA2);
break;
case 3:
SET_IAC3 (0);
SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA3);
break;
case 4:
SET_IAC4 (0);
SET_DBCR0 (GET_DBCR0 () & ~DBCR0_IA4);
break;
}
return 0;
} /* bedbug405_clear */
/* ====================================================================== */
#endif