Commit 30df74d6 authored by Ravi Bangoria's avatar Ravi Bangoria Committed by Michael Ellerman
Browse files

powerpc/watchpoint/xmon: Support 2nd DAWR 



Add support for 2nd DAWR in xmon. With this, we can have two
simultaneous breakpoints from xmon.

Signed-off-by: default avatarRavi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Reviewed-by: default avatarMichael Neuling <mikey@neuling.org>
Link: https://lore.kernel.org/r/20200514111741.97993-17-ravi.bangoria@linux.ibm.com
parent 514db915

arch/powerpc/xmon/xmon.c

+69 −32
Original line number Diff line number Diff line
@@ -112,7 +112,7 @@ struct bpt { 
#define BP_DABR		4



static struct bpt bpts[NBPTS];

static struct bpt dabr;

static struct bpt dabr[HBP_NUM_MAX];

static struct bpt *iabr;

static unsigned bpinstr = 0x7fe00008;	/* trap */
@@ -784,10 +784,17 @@ static int xmon_sstep(struct pt_regs *regs) 


static int xmon_break_match(struct pt_regs *regs)

{

	int i;



	if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) != (MSR_IR|MSR_64BIT))

		return 0;

	if (dabr.enabled == 0)

	for (i = 0; i < nr_wp_slots(); i++) {

		if (dabr[i].enabled)

			goto found;

	}

	return 0;



found:

	xmon_core(regs, 0);

	return 1;

}
@@ -948,13 +955,16 @@ static void insert_bpts(void) 


static void insert_cpu_bpts(void)

{

	int i;

	struct arch_hw_breakpoint brk;



	if (dabr.enabled) {

		brk.address = dabr.address;

		brk.type = (dabr.enabled & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;

		brk.len = DABR_MAX_LEN;

		__set_breakpoint(0, &brk);

	for (i = 0; i < nr_wp_slots(); i++) {

		if (dabr[i].enabled) {

			brk.address = dabr[i].address;

			brk.type = (dabr[i].enabled & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;

			brk.len = 8;

			__set_breakpoint(i, &brk);

		}

	}



	if (iabr)
@@ -1366,6 +1376,35 @@ static long check_bp_loc(unsigned long addr) 
	return 1;

}



static int find_free_data_bpt(void)

{

	int i;



	for (i = 0; i < nr_wp_slots(); i++) {

		if (!dabr[i].enabled)

			return i;

	}

	printf("Couldn't find free breakpoint register\n");

	return -1;

}



static void print_data_bpts(void)

{

	int i;



	for (i = 0; i < nr_wp_slots(); i++) {

		if (!dabr[i].enabled)

			continue;



		printf("   data   "REG"  [", dabr[i].address);

		if (dabr[i].enabled & 1)

			printf("r");

		if (dabr[i].enabled & 2)

			printf("w");

		printf("]\n");

	}

}



static char *breakpoint_help_string =

    "Breakpoint command usage:\n"

    "b                show breakpoints\n"
@@ -1399,10 +1438,9 @@ bpt_cmds(void) 
			printf("Hardware data breakpoint not supported on this cpu\n");

			break;

		}

		if (dabr.enabled) {

			printf("Couldn't find free breakpoint register\n");

		i = find_free_data_bpt();

		if (i < 0)

			break;

		}

		mode = 7;

		cmd = inchar();

		if (cmd == 'r')
@@ -1411,15 +1449,15 @@ bpt_cmds(void) 
			mode = 6;

		else

			termch = cmd;

		dabr.address = 0;

		dabr.enabled = 0;

		if (scanhex(&dabr.address)) {

			if (!is_kernel_addr(dabr.address)) {

		dabr[i].address = 0;

		dabr[i].enabled = 0;

		if (scanhex(&dabr[i].address)) {

			if (!is_kernel_addr(dabr[i].address)) {

				printf(badaddr);

				break;

			}

			dabr.address &= ~HW_BRK_TYPE_DABR;

			dabr.enabled = mode | BP_DABR;

			dabr[i].address &= ~HW_BRK_TYPE_DABR;

			dabr[i].enabled = mode | BP_DABR;

		}



		force_enable_xmon();
@@ -1458,7 +1496,9 @@ bpt_cmds(void) 
			for (i = 0; i < NBPTS; ++i)

				bpts[i].enabled = 0;

			iabr = NULL;

			dabr.enabled = 0;

			for (i = 0; i < nr_wp_slots(); i++)

				dabr[i].enabled = 0;



			printf("All breakpoints cleared\n");

			break;

		}
@@ -1492,14 +1532,7 @@ bpt_cmds(void) 
		if (xmon_is_ro || !scanhex(&a)) {

			/* print all breakpoints */

			printf("   type            address\n");

			if (dabr.enabled) {

				printf("   data   "REG"  [", dabr.address);

				if (dabr.enabled & 1)

					printf("r");

				if (dabr.enabled & 2)

					printf("w");

				printf("]\n");

			}

			print_data_bpts();

			for (bp = bpts; bp < &bpts[NBPTS]; ++bp) {

				if (!bp->enabled)

					continue;
@@ -1959,8 +1992,13 @@ static void dump_207_sprs(void) 


	printf("hfscr  = %.16lx  dhdes = %.16lx rpr    = %.16lx\n",

		mfspr(SPRN_HFSCR), mfspr(SPRN_DHDES), mfspr(SPRN_RPR));

	printf("dawr   = %.16lx  dawrx = %.16lx ciabr  = %.16lx\n",

		mfspr(SPRN_DAWR0), mfspr(SPRN_DAWRX0), mfspr(SPRN_CIABR));

	printf("dawr0  = %.16lx dawrx0 = %.16lx\n",

	       mfspr(SPRN_DAWR0), mfspr(SPRN_DAWRX0));

	if (nr_wp_slots() > 1) {

		printf("dawr1  = %.16lx dawrx1 = %.16lx\n",

		       mfspr(SPRN_DAWR1), mfspr(SPRN_DAWRX1));

	}

	printf("ciabr  = %.16lx\n", mfspr(SPRN_CIABR));

#endif

}
@@ -3909,10 +3947,9 @@ static void clear_all_bpt(void) 
		bpts[i].enabled = 0;



	/* Clear any data or iabr breakpoints */

	if (iabr || dabr.enabled) {

	iabr = NULL;

		dabr.enabled = 0;

	}

	for (i = 0; i < nr_wp_slots(); i++)

		dabr[i].enabled = 0;

}



#ifdef CONFIG_DEBUG_FS

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