ARM: OMAP2+: PRM: create PRM reset source API for the watchdog timer driver
The OMAP watchdog timer driver needs to determine what caused the SoC
to reset for its GETBOOTSTATUS ioctl. So, define a set of standard
reset sources across OMAP SoCs. For OMAP2xxx, 3xxx, and 4xxx SoCs,
define mappings from the SoC-specific reset source register bits to
the standardized reset source IDs. Create SoC-specific PRM functions
that read the appropriate per-SoC register and use the mapping to
return the standardized reset bits. Register the SoC-specific PRM
functions with the common PRM code via prm_register(). Create a
function in the common PRM code, prm_read_reset_sources(), that
calls the SoC-specific function, registered during boot.
This patch does not yet handle some SoCs, such as AM33xx. Those SoCs
were not handled by the code this will replace.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
diff --git a/arch/arm/mach-omap2/prm_common.c b/arch/arm/mach-omap2/prm_common.c
index 8670a3c..e200e4f 100644
--- a/arch/arm/mach-omap2/prm_common.c
+++ b/arch/arm/mach-omap2/prm_common.c
@@ -28,6 +28,8 @@
#include <plat/prcm.h>
#include "prm2xxx_3xxx.h"
+#include "prm2xxx.h"
+#include "prm3xxx.h"
#include "prm44xx.h"
/*
@@ -327,6 +329,30 @@
}
/**
+ * prm_read_reset_sources - return the sources of the SoC's last reset
+ *
+ * Return a u32 bitmask representing the reset sources that caused the
+ * SoC to reset. The low-level per-SoC functions called by this
+ * function remap the SoC-specific reset source bits into an
+ * OMAP-common set of reset source bits, defined in
+ * arch/arm/mach-omap2/prm.h. Returns the standardized reset source
+ * u32 bitmask from the hardware upon success, or returns (1 <<
+ * OMAP_UNKNOWN_RST_SRC_ID_SHIFT) if no low-level read_reset_sources()
+ * function was registered.
+ */
+u32 prm_read_reset_sources(void)
+{
+ u32 ret = 1 << OMAP_UNKNOWN_RST_SRC_ID_SHIFT;
+
+ if (prm_ll_data->read_reset_sources)
+ ret = prm_ll_data->read_reset_sources();
+ else
+ WARN_ONCE(1, "prm: %s: no mapping function defined for reset sources\n", __func__);
+
+ return ret;
+}
+
+/**
* prm_register - register per-SoC low-level data with the PRM
* @pld: low-level per-SoC OMAP PRM data & function pointers to register
*