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* x86: ivybridge: Implement SDRAM initSimon Glass2014-11-21-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement SDRAM init using the Memory Reference Code (mrc.bin) provided in the board directory and the SDRAM SPD information in the device tree. This also needs the Intel Management Engine (me.bin) to work. Binary blobs everywhere: so far we have MRC, ME and microcode. SDRAM init works by setting up various parameters and calling the MRC. This in turn does some sort of magic to work out how much memory there is and the timing parameters to use. It also sets up the DRAM controllers. When the MRC returns, we use the information it provides to map out the available memory in U-Boot. U-Boot normally moves itself to the top of RAM. On x86 the RAM is not generally contiguous, and anyway some RAM may be above 4GB which doesn't work in 32-bit mode. So we relocate to the top of the largest block of RAM we can find below 4GB. Memory above 4GB is accessible with special functions (see physmem). It would be possible to build U-Boot in 64-bit mode but this wouldn't necessarily provide any more memory, since the largest block is often below 4GB. Anyway U-Boot doesn't need huge amounts of memory - even a very large ramdisk seldom exceeds 100-200MB. U-Boot has support for booting 64-bit kernels directly so this does not pose a limitation in that area. Also there are probably parts of U-Boot that will not work correctly in 64-bit mode. The MRC is one. There is some work remaining in this area. Since memory init is very slow (over 500ms) it is possible to save the parameters in SPI flash to speed it up next time. Suspend/resume support is not fully implemented, or at least it is not efficient. With this patch, link boots to a prompt. Signed-off-by: Simon Glass <sjg@chromium.org>
* x86: Emit post codes in startup code for ChromebooksSimon Glass2014-11-21-0/+4
| | | | | | | | | | | | | | | | On x86 it is common to use 'post codes' which are 8-bit hex values emitted from the code and visible to the user. Traditionally two 7-segment displays were made available on the motherboard to show the last post code that was emitted. This allows diagnosis of a boot problem since it is possible to see where the code got to before it died. On modern hardware these codes are not normally visible. On Chromebooks they are displayed by the Embedded Controller (EC), so it is useful to emit them. We must enable this feature for the EC to see the codes, so add an option for this. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
* x86: Save the BIST value on resetSimon Glass2014-11-21-3/+6
| | | | | | | | | | The built in self test value is available in register eax on start-up. Save it so that it can be accessed later. Unfortunately we must wait until the global_data is available before we can do this, so there is a little bit of shuffling to keep it around. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
* x86: Tidy up global descriptor table setupSimon Glass2014-11-21-3/+16
| | | | | | | | This code is a little muddled, so tidy it up. Make sure that we put the GDT in the right place and set it up properly. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
* dm: x86: Support pre-reloc malloc()Simon Glass2014-10-23-0/+7
| | | | | | Add support for this by reserving a block of memory below global_data. Signed-off-by: Simon Glass <sjg@chromium.org>
* dm: x86: Zero global data before board_init_f()Simon Glass2014-10-23-0/+6
| | | | | | | | To permit information to be passed from the early U-Boot code to board_init_f() we cannot zero the global_data in board_init_f(). Instead zero it in the start-up code. Signed-off-by: Simon Glass <sjg@chromium.org>
* Add GPL-2.0+ SPDX-License-Identifier to source filesWolfgang Denk2013-07-24-17/+1
| | | | | | Signed-off-by: Wolfgang Denk <wd@denx.de> [trini: Fixup common/cmd_io.c] Signed-off-by: Tom Rini <trini@ti.com>
* x86: Set up the global data pointer in C instead of asmSimon Glass2013-02-01-6/+0
| | | | | | | | | | | | | | | | We currently assume that the global data pointer is at the start of struct global_data. We want to remove this restriction, and it is easiest to do this in C. Remove the asm code and add equivalent code in C. This idea was proposed by Graeme Russ here: http://patchwork.ozlabs.org/patch/199741/ Signed-off-by: Simon Glass <sjg@chromium.org> [trini: Apply Graeme Russ' comments http://patchwork.ozlabs.org/patch/206305/ here, re-order] Signed-off-by: Tom Rini <trini@ti.com>
* x86: Add back cold- and warm-boot flagsGabe Black2012-12-06-1/+9
| | | | | | | | | | | | | These were removed, but actually are useful. Cold means that we started from a reset/power on. Warm means that we started from another U-Boot. We determine whether u-boot on x86 was warm or cold booted (really if it started at the beginning of the text segment or at the ELF entry point). We plumb the result through to the global data structure. Signed-off-by: Simon Glass <sjg@chromium.org>
* x86: Put global data on the stackGraeme Russ2012-11-28-7/+60
| | | | | | | | | | Putting global data on the stack simplifies the init process (and makes it slightly quicker). During the 'flash' stage of the init sequence, global data is in the CAR stack. After SDRAM is initialised, global data is copied from CAR to the SDRAM stack Signed-off-by: Graeme Russ <graeme.russ@gmail.com> Signed-off-by: Simon Glass <sjg@chromium.org>
* x86: Use fs for global dataGraeme Russ2012-01-04-1/+7
| | | | | | | | | | | | | | | | | | | | | | Use the base address of the 'F' segment as a pointer to the global data structure. By adding the linear address (i.e. the 'D' segment address) as the first word of the global data structure, the address of the global data relative to the 'D' segment can be found simply, for example, by: fs movl 0, %eax This makes the gd 'pointer' writable prior to relocation (by reloading the Global Desctriptor Table) which brings x86 into line with all other arches NOTE: Writing to the gd 'pointer' is expensive (but we only do it twice) but using it to access global data members (read and write) is still fairly cheap -- Changes for v2: - Rebased against changes made to patch #3 - Removed extra indent - Tweaked commit message
* x86: Simplify Flash-to-RAM code execution transitionGraeme Russ2012-01-04-16/+6
| | | | | | | | | | | Move the relocation offset calculation out of assembler and into C. This also paves the way for the upcoming init sequence simplification by adding the board_init_f_r flash to RAM transitional function -- Changes for v2: - Added commit message - Minor adjustment to new stack address comment
* x86: Remove GDR related magic numbersGraeme Russ2012-01-04-1/+2
| | | | | | | | -- Changes for v2: - Use an enum - Add defined for GDT size (previously added in patch 7) - Use X86_ namespace (as per Linux headers)
* x86: Misc cleanupsGraeme Russ2011-11-29-2/+3
| | | | Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
* x86: Add multiboot headerGraeme Russ2011-11-29-0/+20
| | | | | | | | | By adding a multiboot header, U-Boot can be loaded by GRUB2. Using GRUB2 to bootstrap U-Boot is useful for using an existing BIOS to get an initial U-Boot port up and running before implementing the low-level reset vector code, SDRAM init, etc. and overwriting the BIOS Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
* sc520: Create arch asm-offsetsGraeme Russ2011-11-29-1/+2
| | | | Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
* x86: Punt cold- and warm-boot flagsGraeme Russ2011-11-29-2/+0
| | | | | | | Nobody uses them anyway Signed-off-by: Graeme Russ <graeme.russ@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org>
* Convert ISO-8859 files to UTF-8Albert ARIBAUD2011-08-04-1/+1
| | | | | | | | There was a mix of UTF-8 and ISO-8859 files in the U-Boot source tree, which could cause issues with the patchwork review system. This commit converts all ISO-8859 files to UTF-8. Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
* cleanup: Fix typos and misspellings in various files.Mike Williams2011-07-28-1/+1
| | | | | | | | | | | Recieve/Receive recieve/receive Interupt/Interrupt interupt/interrupt Addres/Address addres/address Signed-off-by: Mike Williams <mike@mikebwilliams.com>
* x86: Rename i386 to x86Graeme Russ2011-04-13-0/+132
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
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