omap4: utility function to identify the context of hw init
The basic hardware init of OMAP4(s_init()) can happen in 4
different contexts:
1. SPL running from SRAM
2. U-Boot running from FLASH
3. Non-XIP U-Boot loaded to SDRAM by SPL
4. Non-XIP U-Boot loaded to SDRAM by ROM code using the
Configuration Header feature
What level of hw initialization gets done depends on this
context. Add a utility function to find this context.
Signed-off-by: Aneesh V <aneesh@ti.com>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
diff --git a/arch/arm/include/asm/arch-omap4/sys_proto.h b/arch/arm/include/asm/arch-omap4/sys_proto.h
index 4fa4f4b..6b596b4 100644
--- a/arch/arm/include/asm/arch-omap4/sys_proto.h
+++ b/arch/arm/include/asm/arch-omap4/sys_proto.h
@@ -23,10 +23,12 @@
#include <asm/arch/omap4.h>
#include <asm/io.h>
+#include <asm/omap_common.h>
struct omap_sysinfo {
char *board_string;
};
+extern const struct omap_sysinfo sysinfo;
void gpmc_init(void);
void watchdog_init(void);
@@ -37,6 +39,51 @@
void sdelay(unsigned long);
void set_pl310_ctrl_reg(u32 val);
-extern const struct omap_sysinfo sysinfo;
+static inline u32 running_from_sdram(void)
+{
+ u32 pc;
+ asm volatile ("mov %0, pc" : "=r" (pc));
+ return ((pc >= OMAP44XX_DRAM_ADDR_SPACE_START) &&
+ (pc < OMAP44XX_DRAM_ADDR_SPACE_END));
+}
+
+static inline u8 uboot_loaded_by_spl(void)
+{
+ /*
+ * Configuration Header is not supported yet, so u-boot init running
+ * from SDRAM implies that it was loaded by SPL. When this situation
+ * changes one of these approaches could be taken:
+ * i. Pass a magic from SPL to U-Boot and U-Boot save it at a known
+ * location.
+ * ii. Check the OPP. CH can support only 50% OPP while SPL initializes
+ * the DPLLs at 100% OPP.
+ */
+ return running_from_sdram();
+}
+/*
+ * The basic hardware init of OMAP(s_init()) can happen in 4
+ * different contexts:
+ * 1. SPL running from SRAM
+ * 2. U-Boot running from FLASH
+ * 3. Non-XIP U-Boot loaded to SDRAM by SPL
+ * 4. Non-XIP U-Boot loaded to SDRAM by ROM code using the
+ * Configuration Header feature
+ *
+ * This function finds this context.
+ * Defining as inline may help in compiling out unused functions in SPL
+ */
+static inline u32 omap4_hw_init_context(void)
+{
+#ifdef CONFIG_SPL_BUILD
+ return OMAP_INIT_CONTEXT_SPL;
+#else
+ if (uboot_loaded_by_spl())
+ return OMAP_INIT_CONTEXT_UBOOT_AFTER_SPL;
+ else if (running_from_sdram())
+ return OMAP_INIT_CONTEXT_UBOOT_AFTER_CH;
+ else
+ return OMAP_INIT_CONTEXT_UBOOT_FROM_NOR;
+#endif
+}
#endif