Commit b5c5353d authored by Paul Walmsley's avatar Paul Walmsley
Browse files

ARM: OMAP1: create read_reset_sources() function (for initial use by watchdog) 



On OMAP1, the existing OMAP watchdog driver reads a register directly
from a non-watchdog IP block.  It also does not convert the register's
contents into the standard WDIOF_* bits expected from the
GETBOOTSTATUS ioctl().

To move towards fixing these problems, create an function in
arch/arm/mach-omap1 to return the reset source data.  A subsequent
patch will provide this function to the watchdog driver via
platform_data.

In the long term, the best approach would be to move this function
to a new OMAP1 driver that handles access to the OMAP1 Clock
Generation and Reset Management IP block.  Then no platform_data would
be needed.

Signed-off-by: default avatarPaul Walmsley <paul@pwsan.com>
parent 21325b25

arch/arm/mach-omap1/common.h

+2 −0
Original line number Diff line number Diff line
@@ -90,4 +90,6 @@ extern int ocpi_enable(void); 
static inline int ocpi_enable(void) { return 0; }

#endif



extern int omap1_get_reset_sources(void);



#endif /* __ARCH_ARM_MACH_OMAP1_COMMON_H */

arch/arm/mach-omap1/reset.c

+38 −0
Original line number Diff line number Diff line
@@ -10,6 +10,19 @@ 


#include "common.h"



/* ARM_SYSST bit shifts related to SoC reset sources */

#define ARM_SYSST_POR_SHIFT				5

#define ARM_SYSST_EXT_RST_SHIFT				4

#define ARM_SYSST_ARM_WDRST_SHIFT			2

#define ARM_SYSST_GLOB_SWRST_SHIFT			1



/* Standardized reset source bits (across all OMAP SoCs) */

#define OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT		0

#define OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT		1

#define OMAP_MPU_WD_RST_SRC_ID_SHIFT			3

#define OMAP_EXTWARM_RST_SRC_ID_SHIFT			5





void omap1_restart(char mode, const char *cmd)

{

	/*
@@ -23,3 +36,28 @@ void omap1_restart(char mode, const char *cmd) 


	omap_writew(1, ARM_RSTCT1);

}



/**

 * omap1_get_reset_sources - return the source of the SoC's last reset

 *

 * Returns bits that represent the last reset source for the SoC.  The

 * format is standardized across OMAPs for use by the OMAP watchdog.

 */

int omap1_get_reset_sources(void)

{

	int ret = 0;

	u16 rs;



	rs = __raw_readw(ARM_SYSST);



	if (rs & (1 << ARM_SYSST_POR_SHIFT))

		ret |= 1 << OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT;

	if (rs & (1 << ARM_SYSST_EXT_RST_SHIFT))

		ret |= 1 << OMAP_EXTWARM_RST_SRC_ID_SHIFT;

	if (rs & (1 << ARM_SYSST_ARM_WDRST_SHIFT))

		ret |= 1 << OMAP_MPU_WD_RST_SRC_ID_SHIFT;

	if (rs & (1 << ARM_SYSST_GLOB_SWRST_SHIFT))

		ret |= 1 << OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT;



	return ret;

}

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