diff options
| author | Benoît Thébaudeau <benoit.thebaudeau@advansee.com> | 2013-04-11 09:35:51 +0000 |
|---|---|---|
| committer | Albert ARIBAUD <albert.u.boot@aribaud.net> | 2013-04-12 07:55:07 +0200 |
| commit | da962b71758d52b38a4ed89380d296ed25920d18 (patch) | |
| tree | 414567a20230b6476d0c7c316e02abfc403c70f1 /doc/README.arm-relocation | |
| parent | 8b7cd098ddd130c0dc0d8a3820c3c592978aa9d3 (diff) | |
| download | u-boot-da962b71758d52b38a4ed89380d296ed25920d18.tar.gz | |
nand: mxc: Switch NAND SPL to generic SPL
This also fixes support for mx31pdk and tx25, which had been broken by commit
e05e5de7fae5bec79617e113916dac6631251156.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Diffstat (limited to 'doc/README.arm-relocation')
| -rw-r--r-- | doc/README.arm-relocation | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/doc/README.arm-relocation b/doc/README.arm-relocation index 5a9a2fb071..645b3746c8 100644 --- a/doc/README.arm-relocation +++ b/doc/README.arm-relocation @@ -40,15 +40,15 @@ Boards which are not fixed to support relocation will be REMOVED! ----------------------------------------------------------------------------- -For boards which boot from nand_spl, it is possible to save one copy +For boards which boot from spl, it is possible to save one copy if CONFIG_SYS_TEXT_BASE == relocation address! This prevents that uboot code is copied again in relocate_code(). -example for the tx25 board: +example for the tx25 board booting from NAND Flash: a) cpu starts b) it copies the first page in nand to internal ram - (nand_spl_code) + (spl code) c) end executes this code d) this initialize CPU, RAM, ... and copy itself to RAM (this bin must fit in one page, so board_init_f() @@ -79,20 +79,20 @@ TODO ----------------------------------------------------------------------------- -Relocation with NAND_SPL (example for the tx25): +Relocation with SPL (example for the tx25 booting from NAND Flash): - cpu copies the first page from NAND to 0xbb000000 (IMX_NFC_BASE) and start with code execution on this address. -- The First page contains u-boot code from u-boot:nand_spl/nand_boot_fsl_nfc.c - which inits the dram, cpu registers, reloacte itself to CONFIG_SYS_TEXT_BASE and loads +- The First page contains u-boot code from drivers/mtd/nand/mxc_nand_spl.c + which inits the dram, cpu registers, reloacte itself to CONFIG_SPL_TEXT_BASE and loads the "real" u-boot to CONFIG_SYS_NAND_U_BOOT_DST and starts execution @CONFIG_SYS_NAND_U_BOOT_START - This u-boot does no RAM init, nor CPU register setup. Just look where it has to copy and relocate itself to this address. If relocate address = CONFIG_SYS_TEXT_BASE (not the same, as the - CONFIG_SYS_TEXT_BASE from the nand_spl code), then there is no need + CONFIG_SPL_TEXT_BASE from the spl code), then there is no need to copy, just go on with bss clear and jump to board_init_r. ----------------------------------------------------------------------------- |