omap-common: Common boot code OMAP3 support and cleanup

This introduces OMAP3 support for the common omap boot code, as well as a
major cleanup of the common omap boot code.

First, the omap_boot_parameters structure becomes platform-specific, since its
definition differs a bit across omap platforms. The offsets are removed as well
since it is U-Boot's coding style to use structures for mapping such kind of
data (in the sense that it is similar to registers). It is correct to assume
that romcode structure encoding is the same as U-Boot, given the description
of these structures in the TRMs.

The original address provided by the bootrom is passed to the U-Boot binary
instead of a duplicate of the structure stored in global data. This allows to
have only the relevant (boot device and mode) information stored in global data.
It is also expected that the address where the bootrom stores that information
is not overridden by the U-Boot SPL or U-Boot.

The save_omap_boot_params is expected to handle all special cases where the data
provided by the bootrom cannot be used as-is, so that spl_boot_device and
spl_boot_mode only return the data from global data.

All of this is only relevant when the U-Boot SPL is used. In cases it is not,
save_boot_params should fallback to its weak (or board-specific) definition.
save_omap_boot_params should not be called in that context either.

Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
diff --git a/arch/arm/include/asm/arch-omap3/omap.h b/arch/arm/include/asm/arch-omap3/omap.h
index 194b93b..537d13b 100644
--- a/arch/arm/include/asm/arch-omap3/omap.h
+++ b/arch/arm/include/asm/arch-omap3/omap.h
@@ -142,6 +142,7 @@
 
 #define NON_SECURE_SRAM_START		0x40208000 /* Works for GP & EMU */
 #define NON_SECURE_SRAM_END		0x40210000
+#define SRAM_SCRATCH_SPACE_ADDR		0x4020E000
 
 #define LOW_LEVEL_SRAM_STACK		0x4020FFFC
 
@@ -245,4 +246,16 @@
 /* ABB tranxdone mask */
 #define OMAP_ABB_MPU_TXDONE_MASK	(0x1 << 26)
 
+/* Boot parameters */
+#ifndef __ASSEMBLY__
+struct omap_boot_parameters {
+	unsigned int boot_message;
+	unsigned char boot_device;
+	unsigned char reserved;
+	unsigned char reset_reason;
+	unsigned char ch_flags;
+	unsigned int boot_device_descriptor;
+};
+#endif
+
 #endif
diff --git a/arch/arm/include/asm/arch-omap3/sys_proto.h b/arch/arm/include/asm/arch-omap3/sys_proto.h
index 3e45ce1..cfa4d58 100644
--- a/arch/arm/include/asm/arch-omap3/sys_proto.h
+++ b/arch/arm/include/asm/arch-omap3/sys_proto.h
@@ -75,4 +75,6 @@
 void do_omap3_emu_romcode_call(u32 service_id, u32 parameters);
 void omap3_set_aux_cr_secure(u32 acr);
 u32 warm_reset(void);
+
+void save_omap_boot_params(void);
 #endif