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u-boot/arch/powerpc/lib/ticks.S

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Initial revision
2001-11-26 22:06:16 +00:00
/*
* (C) Copyright 2000, 2001
* Erik Theisen, Wave 7 Optics, etheisen@mindspring.com.
* base on code by
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
Add GPL-2.0+ SPDX-License-Identifier to source files Signed-off-by: Wolfgang Denk <wd@denx.de> [trini: Fixup common/cmd_io.c] Signed-off-by: Tom Rini <trini@ti.com>
2013-07-08 07:37:19 +00:00
* SPDX-License-Identifier: GPL-2.0+
Initial revision
2001-11-26 22:06:16 +00:00
*/
#include <ppc_asm.tmpl>
#include <ppc_defs.h>
#include <config.h>
#include <watchdog.h>
/*
* unsigned long long get_ticks(void);
*
* read timebase as "long long"
*/
.globl get_ticks
get_ticks:
1: mftbu r3
mftb r4
mftbu r5
cmp 0,r3,r5
bne 1b
blr
/*
* Delay for a number of ticks
*/
.globl wait_ticks
wait_ticks:
ppc: Create a stack frame for wait_ticks() wait_ticks() calls get_ticks() without building a back chain which makes gdb unhappy when doing back trace. This can also cause improper memory accesses. Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
2012-07-16 21:25:40 +00:00
stwu r1, -16(r1)
mflr r0 /* save link register */
stw r0, 20(r1) /* Use r0 or GDB will be unhappy */
powerpc/lib: fix unsafe register handling in wait_ticks If watchdog is enabled, the arch/powerpc/lib/ticks.S::wait_ticks() function calls the function specified by the WATCHDOG_RESET macro. The wait_ticks function depends on the registers r0, r6 and r7 being preserved however that is not guaranteed, e.g. if the reset function is a C function this will probably overwrite r0 and cause an endless loop. The following patch changes to using r14+r15 instead of r6+r7 (to resemble what would have been generated by a C compiler) and saves all necessary registers on the stack. The patch has been tested on a custom MPC5125 based machine using the 512x powerpc architecture. Signed-off-by: Mats Karrman <mats.karrman@tritech.se> Cc: Wolfgang Denk <wd@denx.de> Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se> Tested-by: Stefan Roese <sr@denx.de>
2013-04-09 15:10:59 +00:00
stw r14, 12(r1) /* save used registers */
stw r15, 8(r1)
mr r14, r3 /* save tick count */
Initial revision
2001-11-26 22:06:16 +00:00
bl get_ticks /* Get start time */
/* Calculate end time */
powerpc/lib: fix unsafe register handling in wait_ticks If watchdog is enabled, the arch/powerpc/lib/ticks.S::wait_ticks() function calls the function specified by the WATCHDOG_RESET macro. The wait_ticks function depends on the registers r0, r6 and r7 being preserved however that is not guaranteed, e.g. if the reset function is a C function this will probably overwrite r0 and cause an endless loop. The following patch changes to using r14+r15 instead of r6+r7 (to resemble what would have been generated by a C compiler) and saves all necessary registers on the stack. The patch has been tested on a custom MPC5125 based machine using the 512x powerpc architecture. Signed-off-by: Mats Karrman <mats.karrman@tritech.se> Cc: Wolfgang Denk <wd@denx.de> Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se> Tested-by: Stefan Roese <sr@denx.de>
2013-04-09 15:10:59 +00:00
addc r14, r4, r14 /* Compute end time lower */
addze r15, r3 /* and end time upper */
Initial revision
2001-11-26 22:06:16 +00:00
WATCHDOG_RESET /* Trigger watchdog, if needed */
1: bl get_ticks /* Get current time */
powerpc/lib: fix unsafe register handling in wait_ticks If watchdog is enabled, the arch/powerpc/lib/ticks.S::wait_ticks() function calls the function specified by the WATCHDOG_RESET macro. The wait_ticks function depends on the registers r0, r6 and r7 being preserved however that is not guaranteed, e.g. if the reset function is a C function this will probably overwrite r0 and cause an endless loop. The following patch changes to using r14+r15 instead of r6+r7 (to resemble what would have been generated by a C compiler) and saves all necessary registers on the stack. The patch has been tested on a custom MPC5125 based machine using the 512x powerpc architecture. Signed-off-by: Mats Karrman <mats.karrman@tritech.se> Cc: Wolfgang Denk <wd@denx.de> Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se> Tested-by: Stefan Roese <sr@denx.de>
2013-04-09 15:10:59 +00:00
subfc r4, r4, r14 /* Subtract current time from end time */
subfe. r3, r3, r15
Initial revision
2001-11-26 22:06:16 +00:00
bge 1b /* Loop until time expired */
powerpc/lib: fix unsafe register handling in wait_ticks If watchdog is enabled, the arch/powerpc/lib/ticks.S::wait_ticks() function calls the function specified by the WATCHDOG_RESET macro. The wait_ticks function depends on the registers r0, r6 and r7 being preserved however that is not guaranteed, e.g. if the reset function is a C function this will probably overwrite r0 and cause an endless loop. The following patch changes to using r14+r15 instead of r6+r7 (to resemble what would have been generated by a C compiler) and saves all necessary registers on the stack. The patch has been tested on a custom MPC5125 based machine using the 512x powerpc architecture. Signed-off-by: Mats Karrman <mats.karrman@tritech.se> Cc: Wolfgang Denk <wd@denx.de> Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se> Tested-by: Stefan Roese <sr@denx.de>
2013-04-09 15:10:59 +00:00
lwz r15, 8(r1) /* restore saved registers */
lwz r14, 12(r1)
lwz r0, 20(r1)
ppc: Create a stack frame for wait_ticks() wait_ticks() calls get_ticks() without building a back chain which makes gdb unhappy when doing back trace. This can also cause improper memory accesses. Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
2012-07-16 21:25:40 +00:00
addi r1,r1,16
powerpc/lib: fix unsafe register handling in wait_ticks If watchdog is enabled, the arch/powerpc/lib/ticks.S::wait_ticks() function calls the function specified by the WATCHDOG_RESET macro. The wait_ticks function depends on the registers r0, r6 and r7 being preserved however that is not guaranteed, e.g. if the reset function is a C function this will probably overwrite r0 and cause an endless loop. The following patch changes to using r14+r15 instead of r6+r7 (to resemble what would have been generated by a C compiler) and saves all necessary registers on the stack. The patch has been tested on a custom MPC5125 based machine using the 512x powerpc architecture. Signed-off-by: Mats Karrman <mats.karrman@tritech.se> Cc: Wolfgang Denk <wd@denx.de> Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se> Tested-by: Stefan Roese <sr@denx.de>
2013-04-09 15:10:59 +00:00
mtlr r0
Initial revision
2001-11-26 22:06:16 +00:00
blr
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