From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Fri, 26 Jan 2018 17:16:21 +0100 Subject: [U-Boot] [PATCH] imx-common: spl: Allow booting from eMMC when SPL is loaded from non-eMMC device In-Reply-To: References: <20180126145723.15991-1-lukma@denx.de> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 01/26/2018 05:05 PM, Stefano Babic wrote: > On 26/01/2018 15:57, Lukasz Majewski wrote: >> This patch tries to solve the problem described in following patch: >> https://patchwork.ozlabs.org/patch/796237/ >> >> The main argument against the above code was the potential lack of >> consistency if we boot SPL from the SD card (and then eMMC may load >> u-boot proper). >> >> This patch preserves this consistency if spl_boot_device() detects boot >> from either SD card or eMMC. >> >> It only will change boot device if boot from non-SD/eMMC device is >> detected - i.e SPI-NOR (as in this case). >> >> Signed-off-by: Lukasz Majewski >> --- >> >> arch/arm/mach-imx/spl.c | 7 ++++++- >> 1 file changed, 6 insertions(+), 1 deletion(-) >> >> diff --git a/arch/arm/mach-imx/spl.c b/arch/arm/mach-imx/spl.c >> index 6c16872f59..735d9f6261 100644 >> --- a/arch/arm/mach-imx/spl.c >> +++ b/arch/arm/mach-imx/spl.c >> @@ -134,7 +134,12 @@ int g_dnl_bind_fixup(struct usb_device_descriptor *dev, const char *name) >> /* called from spl_mmc to see type of boot mode for storage (RAW or FAT) */ >> u32 spl_boot_mode(const u32 boot_device) >> { >> - switch (spl_boot_device()) { >> + u32 spl_bd = spl_boot_device(); >> + >> + if (spl_bd != BOOT_DEVICE_MMC1) >> + spl_bd = boot_device; >> + >> + switch (spl_bd) { >> /* for MMC return either RAW or FAT mode */ >> case BOOT_DEVICE_MMC1: >> case BOOT_DEVICE_MMC2: >> > > But have we not board_boot_order() for such as cases ? It is a wek > function and you can define it in your board code. Put in mach-imx, it > is valid for all boards. After a bit of offline discussion with Lukasz, I think I understand what the problem is. The SPL common code calls spl_boot_device() to determine which boot device to boot from next ; in his case, SPI or eMMC. In case eMMC is selected, the SPL MMC common code then calls spl_boot_mode() (different function than spl_boot_device()) to determine whether the content on SD/eMMC is RAW or on a FS. The iMX implementation (and layerspace too) does extra stuff in the implementation of spl_boot_mode() by calling spl_boot_device() again, which is wrong. spl_boot_mode() is only used by spl_mmc.c , so we are certain the system is booting from SD/MMC . By turning this around, if the board code did override the board_boot_order() to load the next payload from SD/MMC/eMMC AND started SPL from non-SD/MMC/eMMC device , calling spl_boot_device() in spl_boot_mode() implementation will return bogus result and the spl_boot_mode() will fail in the default: case. Thus, the fix here is to do what ie. socfpga does, just discern whether the content on SD/MMC/eMMC is RAW or FS and do not do any extra checks. -- Best regards, Marek Vasut