From 78f455c055ddf55a1a2dd6ae5e2d060ed2e5bd0e Mon Sep 17 00:00:00 2001 From: Sricharan Date: Tue, 15 Nov 2011 09:50:03 -0500 Subject: omap4/5: Add support for booting with CH. Configuration header(CH) is 512 byte header attached to an OMAP boot image that will help ROM code to initialize clocks, SDRAM etc and copy U-Boot directly into SDRAM. CH can help us in by-passing SPL and directly boot U-boot, hence it's an alternative for SPL. However, we intend to support both CH and SPL for OMAP4/5. Initialization done through CH is limited and is not equivalent to that done by SPL. So U-Boot has to distinguish between the two cases and handle them accordingly. This patch takes care of doing this. Signed-off-by: sricharan Signed-off-by: Sandeep Paulraj --- arch/arm/include/asm/arch-omap4/sys_proto.h | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) (limited to 'arch/arm/include/asm/arch-omap4/sys_proto.h') diff --git a/arch/arm/include/asm/arch-omap4/sys_proto.h b/arch/arm/include/asm/arch-omap4/sys_proto.h index b8113e15aa..4146e21818 100644 --- a/arch/arm/include/asm/arch-omap4/sys_proto.h +++ b/arch/arm/include/asm/arch-omap4/sys_proto.h @@ -55,6 +55,13 @@ u32 omap_sdram_size(void); u32 cortex_rev(void); void init_omap_revision(void); void do_io_settings(void); +/* + * This is used to verify if the configuration header + * was executed by Romcode prior to control of transfer + * to the bootloader. SPL is responsible for saving and + * passing this to the u-boot. + */ +extern struct omap_boot_parameters boot_params; static inline u32 running_from_sdram(void) { @@ -67,15 +74,17 @@ static inline u32 running_from_sdram(void) 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. + * u-boot can be running from sdram either because of configuration + * Header or by SPL. If because of CH, then the romcode sets the + * CHSETTINGS executed bit to true in the boot parameter structure that + * it passes to the bootloader.This parameter is stored in the ch_flags + * variable by both SPL and u-boot.Check out for CHSETTINGS, which is a + * mandatory section if CH is present. */ - return running_from_sdram(); + if ((boot_params.ch_flags) & (CH_FLAGS_CHSETTINGS)) + return 0; + else + return running_from_sdram(); } /* * The basic hardware init of OMAP(s_init()) can happen in 4 -- cgit v1.2.1