On 13 Jun 2017, at 11:47, Marek Vasut marex@denx.de wrote:
On 06/13/2017 11:44 AM, Dr. Philipp Tomsich wrote:
Marek,
On 13 Jun 2017, at 10:42, Marek Vasut <marex@denx.de mailto:marex@denx.de> wrote:
On 06/13/2017 03:51 AM, Kever Yang wrote:
Hi Marek,
Hi,
On 06/07/2017 02:28 PM, Marek Vasut wrote:
On 06/07/2017 04:28 AM, Kever Yang wrote:
Hi Andre, Steve, Marek,
Could you help to check how to make it work with this patch on sunxi, bcm and socfpga platform?
The socfpga expects the hook at that exact position (0x40 I think) , so if you moved it somewhere, you broke socfpga.
I know this break socfpga, and that's why I cc you for help, could you help the take a look if we can have a solution on socfpga to "make it work with this patch"?
Can you generate the same u-boot binary with this patch ? If so, then it will work on socfpga. SoCFPGA expects that small piece of stuff at offset 0x40 , so if you move this boot0 hook, it will break. HTH
So the SoCFPGA-implementation relies on the boot0 hook to always start at 0x40? Then this needs fixing anyway… or it will break once someone else touches the armv7 startup code.
I think it's not just the SoCFPGA.
What I am saying is that the boot0-hook is intended to add a header before the actual U-Boot code (as Andre had originally stated in his commit message and as various comments around the boot0 hook also suggest):
arm/arm64: implement a boot header capability
Some SPL loaders (like Allwinner's boot0, and Broadcom's boot0) require a header before the actual U-Boot binary to both check its validity and to find other data to load. Sometimes this header may only be a few bytes of information, and sometimes this might simply be space that needs to be reserved for a post-processing tool.
However, the actual start of the boot0-hook in the U-Boot today is right after the vector-table (which is 0x40 long), which has a few interesting consequences for various architectures: - sunxi: doesn’t matter - socfpga: boot0 hook relies on something being in front of it, as it uses a ".balign 64, …” to advance to 0x40 - rockchip: comes too late to allow inserting the word-sized field at the very start (and to move the vectors back by a word).
Now having looked at the implementation in arch/arm/mach-socfpga/include/mach/boot0.h it is clear why Kever’s change breaks this code: .balign will not forward to 0x40 (after all, 0x0 is also 64-byte aligned).
Once the boot0 hook is at the beginning of the binary (as always intended), this will need to become a .space or .fill directive.
That said, I read your comment to mean that the following changes would work for SoCFPGA: 1.arch/arm/lib/vectors.S: #if CONFIG_IS_ENABLED(BOOT0_HOOK) … pull in the boot0 hook, which needs to contain the vectors #else b reset … remaining vectors … #endif 2.boot0.h (for socfpga): b reset … remaining vectors … /* now at 0x40 */ … whatever currently lives in the boot0.h for socfpga ...
Ok?
I'm not sure I understand what you're trying to say. IIRC the SoCFPGA bootrom checks the content at 0x40-0x48 in SRAM and then jumps to 0x50 if the content is valid. Otherwise it reloads the content from SD/SPI/NAND…
Thanks for the background info. With this, it should be possible to create a new version of the patch that also correctly handles socfpga.
Regards, Philipp.