From e46fedfeb214d118b9983d11fcc929ed49f5ccd7 Mon Sep 17 00:00:00 2001 From: Timur Tabi Date: Thu, 4 Aug 2011 18:03:41 -0500 Subject: powerpc/85xx: introduce and document CONFIG_SYS_CCSRBAR macros Introduce the CONFIG_SYS_CCSRBAR_PHYS_HIGH and CONFIG_SYS_CCSRBAR_PHYS_LOW macros, which contain the high and low portions of CONFIG_SYS_CCSRBAR_PHYS. This is necessary for the assembly-language code that relocates CCSR, since the assembler does not understand 64-bit constants. CONFIG_SYS_CCSRBAR_PHYS is automatically defined from the CONFIG_SYS_CCSRBAR_PHYS_HIGH and CONFIG_SYS_CCSRBAR_PHYS_LOW macros, so it should not be defined in a board header file. Similarly, CONFIG_SYS_CCSRBAR_DEFAULT is defined for each SOC in config_mpc85xx.h, so it should also not be defined in the board header file. CONFIG_SYS_CCSR_DO_NOT_RELOCATE is a "short-cut" macro that guarantees that CONFIG_SYS_CCSRBAR_PHYS is set to the same value as CONFIG_SYS_CCSRBAR_DEFAULT, and so CCSR will not be relocated. Since CONFIG_SYS_CCSRBAR_DEFAULT is locked to a fixed value, multi-stage U-Boot builds (e.g. NAND) are required to relocate CCSR only during the last stage (i.e. the "real" U-Boot). All other stages should define CONFIG_SYS_CCSR_DO_NOT_RELOCATE to ensure that CCSR is not relocated. README is updated with descriptions of all the CONFIG_SYS_CCSRBAR_xxx macros. Signed-off-by: Timur Tabi Signed-off-by: Kumar Gala --- README | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'README') diff --git a/README b/README index a43da97a41..91b6695cf9 100644 --- a/README +++ b/README @@ -2862,6 +2862,43 @@ Low Level (hardware related) configuration options: and RPXsuper) to be able to adjust the position of the IMMR register after a reset. +- CONFIG_SYS_CCSRBAR_DEFAULT: + Default (power-on reset) physical address of CCSR on Freescale + PowerPC SOCs. + +- CONFIG_SYS_CCSRBAR: + Virtual address of CCSR. On a 32-bit build, this is typically + the same value as CONFIG_SYS_CCSRBAR_DEFAULT. + + CONFIG_SYS_DEFAULT_IMMR must also be set to this value, + for cross-platform code that uses that macro instead. + +- CONFIG_SYS_CCSRBAR_PHYS: + Physical address of CCSR. CCSR can be relocated to a new + physical address, if desired. In this case, this macro should + be set to that address. Otherwise, it should be set to the + same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR + is typically relocated on 36-bit builds. It is recommended + that this macro be defined via the _HIGH and _LOW macros: + + #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH + * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) + +- CONFIG_SYS_CCSRBAR_PHYS_HIGH: + Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically + either 0 (32-bit build) or 0xF (36-bit build). This macro is + used in assembly code, so it must not contain typecasts or + integer size suffixes (e.g. "ULL"). + +- CONFIG_SYS_CCSRBAR_PHYS_LOW: + Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is + used in assembly code, so it must not contain typecasts or + integer size suffixes (e.g. "ULL"). + +- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: + If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be + forced to a value that ensures that CCSR is not relocated. + - Floppy Disk Support: CONFIG_SYS_FDC_DRIVE_NUMBER -- cgit v1.2.3