blob: 4516f2f48ea477ba49db4d333c9ba3430b28fc1b [file] [log] [blame]
/*
* Bedbug Functions specific to the MPC860 chip
*/
#include <common.h>
#include <command.h>
#include <linux/ctype.h>
#include <bedbug/bedbug.h>
#include <bedbug/regs.h>
#include <bedbug/ppc.h>
#include <bedbug/type.h>
#if ((CONFIG_COMMANDS & CFG_CMD_BEDBUG) || defined(CONFIG_CMD_BEDBUG)) && defined(CONFIG_8xx)
#define MAX_BREAK_POINTS 2
extern CPU_DEBUG_CTX bug_ctx;
void bedbug860_init __P((void));
void bedbug860_do_break __P((cmd_tbl_t*,int,int,char*[]));
void bedbug860_break_isr __P((struct pt_regs*));
int bedbug860_find_empty __P((void));
int bedbug860_set __P((int,unsigned long));
int bedbug860_clear __P((int));
/* ======================================================================
* Initialize the global bug_ctx structure for the MPC860. Clear all
* of the breakpoints.
* ====================================================================== */
void bedbug860_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 = bedbug860_do_break;
bug_ctx.break_isr = bedbug860_break_isr;
bug_ctx.find_empty = bedbug860_find_empty;
bug_ctx.set = bedbug860_set;
bug_ctx.clear = bedbug860_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 860. 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 bedbug860_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_CMPA(); break;
case 2: addr = GET_CMPB(); break;
case 3: addr = GET_CMPC(); break;
case 4: addr = GET_CMPD(); 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;
} /* bedbug860_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 bedbug860_break_isr( struct pt_regs *regs )
{
unsigned long addr; /* Address stopped at */
unsigned long cause; /* Address stopped at */
/* -------------------------------------------------- */
cause = GET_ICR();
if( !(cause & 0x00000004)) {
printf( "Not an instruction breakpoint (ICR 0x%08lx)\n", cause );
return;
}
addr = regs->nip;
if( addr == GET_CMPA() )
{
bug_ctx.current_bp = 1;
}
else if( addr == GET_CMPB() )
{
bug_ctx.current_bp = 2;
}
else if( addr == GET_CMPC() )
{
bug_ctx.current_bp = 3;
}
else if( addr == GET_CMPD() )
{
bug_ctx.current_bp = 4;
}
bedbug_main_loop( addr, regs );
return;
} /* bedbug860_break_isr */
/* ======================================================================
* Look through all of the hardware breakpoints available to see if one
* is unused.
* ====================================================================== */
int bedbug860_find_empty( void )
{
/* -------------------------------------------------- */
if( GET_CMPA() == 0 )
return 1;
if( GET_CMPB() == 0 )
return 2;
if( GET_CMPC() == 0 )
return 3;
if( GET_CMPD() == 0 )
return 4;
return 0;
} /* bedbug860_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 bedbug860_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 )
{
bug_ctx.hw_debug_enabled = 1;
SET_DER( GET_DER() | 0x00000004 );
}
switch( which_bp )
{
case 1:
SET_CMPA( addr );
SET_ICTRL( GET_ICTRL() | 0x80080800 ); /* CTA=Equal,IW0=Match A,SIW0EN */
break;
case 2:
SET_CMPB( addr );
SET_ICTRL( GET_ICTRL() | 0x10020400 ); /* CTB=Equal,IW1=Match B,SIW1EN */
break;
case 3:
SET_CMPC( addr );
SET_ICTRL( GET_ICTRL() | 0x02008200 ); /* CTC=Equal,IW2=Match C,SIW2EN */
break;
case 4:
SET_CMPD( addr );
SET_ICTRL( GET_ICTRL() | 0x00404100 ); /* CTD=Equal,IW3=Match D,SIW3EN */
break;
}
return which_bp;
} /* bedbug860_set */
/* ======================================================================
* Disable a specific breakoint by setting the appropriate IACx register
* to zero and claring the instruction address breakpoint in DBCR0.
* ====================================================================== */
int bedbug860_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_CMPA( 0 );
SET_ICTRL( GET_ICTRL() & ~0x80080800 ); /* CTA=Equal,IW0=Match A,SIW0EN */
break;
case 2:
SET_CMPB( 0 );
SET_ICTRL( GET_ICTRL() & ~0x10020400 ); /* CTB=Equal,IW1=Match B,SIW1EN */
break;
case 3:
SET_CMPC( 0 );
SET_ICTRL( GET_ICTRL() & ~0x02008200 ); /* CTC=Equal,IW2=Match C,SIW2EN */
break;
case 4:
SET_CMPD( 0 );
SET_ICTRL( GET_ICTRL() & ~0x00404100 ); /* CTD=Equal,IW3=Match D,SIW3EN */
break;
}
return 0;
} /* bedbug860_clear */
/* ====================================================================== */
#endif