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Diffstat (limited to 'qemu/roms/u-boot/doc/SPL/README.omap3')
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diff --git a/qemu/roms/u-boot/doc/SPL/README.omap3 b/qemu/roms/u-boot/doc/SPL/README.omap3 deleted file mode 100644 index c77ca4300..000000000 --- a/qemu/roms/u-boot/doc/SPL/README.omap3 +++ /dev/null @@ -1,52 +0,0 @@ -Overview of SPL on OMAP3 devices -================================ - -Introduction ------------- - -This document provides an overview of how SPL functions on OMAP3 (and related -such as am35x and am37x) processors. - -Methodology ------------ - -On these platforms the ROM supports trying a sequence of boot devices. Once -one has been used successfully to load SPL this information is stored in memory -and the location stored in a register. We will read this to determine where to -read U-Boot from in turn. - -Memory Map ----------- - -This is an example of a typical setup. See top-level README for documentation -of which CONFIG variables control these values. For a given board and the -amount of DRAM available to it different values may need to be used. -Note that the size of the SPL text rodata and data is enforced with a CONFIG -option and growing over that size results in a link error. The SPL stack -starts at the top of SRAM (which is configurable) and grows downward. The -space between the top of SRAM and the enforced upper bound on the size of the -SPL text, data and rodata is considered the safe stack area. Details on -confirming this behavior are shown below. - -A portion of the system memory map looks as follows: -SRAM: 0x40200000 - 0x4020FFFF -DDR1: 0x80000000 - 0xBFFFFFFF - -Option 1 (SPL only): -0x40200800 - 0x4020BBFF: Area for SPL text, data and rodata -0x4020E000 - 0x4020FFFC: Area for the SPL stack. -0x80000000 - 0x8007FFFF: Area for the SPL BSS. -0x80100000: CONFIG_SYS_TEXT_BASE of U-Boot -0x80208000 - 0x80307FFF: malloc() pool available to SPL. - -Option 2 (SPL or X-Loader): -0x40200800 - 0x4020BBFF: Area for SPL text, data and rodata -0x4020E000 - 0x4020FFFC: Area for the SPL stack. -0x80008000: CONFIG_SYS_TEXT_BASE of U-Boot -0x87000000 - 0x8707FFFF: Area for the SPL BSS. -0x87080000 - 0x870FFFFF: malloc() pool available to SPL. - -For the areas that reside within DDR1 they must not be used prior to s_init() -completing. Note that CONFIG_SYS_TEXT_BASE must be clear of the areas that SPL -uses while running. This is why we have two versions of the memory map that -only vary in where the BSS and malloc pool reside. |