From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukasz Majewski Date: Wed, 4 Sep 2019 11:54:40 +0200 Subject: [U-Boot] [PATCH] imx: Introduce CONFIG_SPL_FORCE_MMC_BOOT to force MMC boot on falcon mode In-Reply-To: References: <20190903214358.5127-1-lukma@denx.de> <20190904104655.46a9ad84@jawa> Message-ID: <20190904115440.54ba5081@jawa> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Stefano, Heiko, > On 04/09/19 10:46, Lukasz Majewski wrote: > > Hi Heiko, > > > >> Hello Lukasz, > >> > >> added Stefano to cc as he is the imx custodian. > > > > I've relied on patman ... Thanks for adding Stefano to CC. > > > >> > >> Am 03.09.2019 um 23:43 schrieb Lukasz Majewski: > >>> This change tries to fix the following problem: > >>> > >>> - The board boots (to be more precise - ROM loads SPL) from a slow > >>> SPI-NOR memory. > >>> As a result the spl_boot_device() will return SPI-NOR as a boot > >>> device (which is correct). > >>> > >>> - The problem is that in 'falcon boot' the eMMC is used as a boot > >>> medium to load kernel from its partition. > >>> Calling spl_boot_device() will break things as it returns > >>> SPI-NOR device. > >>> > >>> To fix this issue the new CONFIG_SPL_FORCE_MMC_BOOT Kconfig flag > >>> is introduced to handle this special use case. By default it is > >>> not defined, so there is no change in the legacy code flow. > >>> > >>> Signed-off-by: Lukasz Majewski > >>> > >>> > >>> --- > >>> > >>> This patch is a follow up of previous discussion/fix: > >>> https://patchwork.ozlabs.org/patch/796237/ > >>> > >>> Travis-CI: > >>> https://travis-ci.org/lmajewski/u-boot-dfu/builds/580272414 > >>> --- > >>> arch/arm/mach-imx/spl.c | 11 +++++++++++ > >>> common/spl/Kconfig | 7 +++++++ > >>> 2 files changed, 18 insertions(+) > >> > >> I have just similiar change for an imx6ull based board ... > > > > Also one more of my boards uses this trick (i.MX28 based one). > > > >> just antoher usecase: In factory empty board boots into USB SDP > >> mode, and SPL gets loaded with usb_loader ... SPL detects a sd > >> card (there is no sd card slot mounted, mmc boot is disabled! They > >> attach only one for installing software) > > > > So there is no dedicated SD card slot (also the mmc is disabled on > > that point). > > Instead, in the factory the sd card is attached to pads - just for > > this time. > > > >> and boots U-Boot and system from sd card. > >> Than all software gets installed fully automated with the help of > >> swupdate ... > > > > Ok. > > > >> > >>> diff --git a/arch/arm/mach-imx/spl.c b/arch/arm/mach-imx/spl.c > >>> index 1f230aca3397..daa3d8f7ed94 100644 > >>> --- a/arch/arm/mach-imx/spl.c > >>> +++ b/arch/arm/mach-imx/spl.c > >>> @@ -178,7 +178,18 @@ 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) { > >>> +/* > >>> + * When CONFIG_SPL_FORCE_MMC_BOOT is defined the 'boot_device' is > >>> used > >>> + * unconditionally to decide about device to use for booting. > >>> + * This is crucial for falcon boot mode, when board boots up > >>> (i.e. ROM > >>> + * loads SPL) from slow SPI-NOR memory and afterwards the SPL's > >>> 'falcon' boot > >>> + * mode is used to load Linux OS from eMMC partition. > >>> + */ > >>> +#ifdef CONFIG_SPL_FORCE_MMC_BOOT > >>> + switch (boot_device) { > >>> +#else > >>> switch (spl_boot_device()) { > >>> +#endif > >> > >> Just dummy question .. couldn;t we switch to use always > >> boot_device? > > > > Stefano has provided some rationale for the need of > > spl_boot_device() in the previous version of this fix [1]: > > > > https://patchwork.ozlabs.org/patch/796237/ > > > > > >> > >> In my case I had a board specific: > >> > >> void board_boot_order(u32 *spl_boot_list) > >> { > >> spl_boot_list[0] = BOOT_DEVICE_MMC1; > >> spl_boot_list[1] = BOOT_DEVICE_SPI; > >> spl_boot_list[2] = BOOT_DEVICE_BOARD; > >> spl_boot_list[3] = BOOT_DEVICE_NONE; > >> } > >> > >> which leads that BOOT_DEVICE_MMC1 is passed to spl_boot_mode() > > > > Is your board normally booting from MMC or SPI-NOR (from where SoC > > ROM loads SPL) ? > > > >> > >> If MMC1 is not found, it tries to boot U-Boot from SPI, and if > >> this is empty, as fallback board go into USB SDP mode. > >> > >> The weak function of board_boot_order is: > >> > >> __weak void board_boot_order(u32 *spl_boot_list) > >> { > >> spl_boot_list[0] = spl_boot_device(); > >> } > >> > >> which is exactly what we pass to spl_boot_mode() ... so instead > >> calling spl_boot_device() twice we can use the passed boot_device > >> ... and save the ifdef and new Kconfig option. > >> > >> But may I oversee something ? > > > > Please read the Stefano's reply from [1] - the spl_boot_device() > > has a valid use cases as well. > > Nevertheless, why do we need to add a new compiler switch if this can > be check into board code ? You just need that spl_boot_device() > returns the device you want (MMC for falcon boot). Current status: git grep -n "spl_boot_mode" | grep weak common/spl/spl_mmc.c:287:u32 __weak spl_boot_mode(const u32 boot_device) git grep -n "board_boot_order" | grep weak common/spl/spl.c:491:__weak void board_boot_order(u32 *spl_boot_list) The spl_boot_device() is defined in arch/arm/mach-imx/spl.c [*] as a NON __weak function: git grep -n "spl_boot_device" | grep weak Shall I make this function [*] as __weak and provide override for it in the board file? The problem is in the call of spl_boot_mode() (which is overridden already in arch/arm/mach-imx/spl.c) at common/spl/spl_mmc.c Which then calls spl_boot_device() [**], which may return (correctly) SPI-NOR for eMMC. As is now spl_boot_device() is not a __weak function. > Why do you need to > force it in this way ? The option is to use the proposed patch to make spl_boot_device as a weak function. > > Regards, > Stefano > > > > >> > >>> /* for MMC return either RAW or FAT mode */ > >>> case BOOT_DEVICE_MMC1: > >>> case BOOT_DEVICE_MMC2: > >>> diff --git a/common/spl/Kconfig b/common/spl/Kconfig > >>> index f467eca2be72..3460beb62d59 100644 > >>> --- a/common/spl/Kconfig > >>> +++ b/common/spl/Kconfig > >>> @@ -607,6 +607,13 @@ config SPL_MMC_SUPPORT > >>> this option to build the drivers in drivers/mmc as > >>> part of an SPL build. > >>> > >>> +config SPL_FORCE_MMC_BOOT > >>> + bool "Force SPL's falcon boot from MMC" > >>> + depends on SPL_MMC_SUPPORT > >>> + default n > >>> + help > >>> + Force SPL's falcon boot to use MMC device for Linux > >>> kernel booting. > >> > >> Hmm... falcon boot is just one use case. I would drop "falcon boot" > >> It just to force boot from MMC. > > > > Ok. I will rewrite the help message. > > > >> > >>> + > >>> config SPL_MMC_TINY > >>> bool "Tiny MMC framework in SPL" > >>> depends on SPL_MMC_SUPPORT > >>> > >> > >> bye, > >> Heiko > > > > > > > > Best regards, > > > > Lukasz Majewski > > > > -- > > > > DENX Software Engineering GmbH, Managing Director: Wolfgang > > Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, > > Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: > > lukma at denx.de > > Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma at denx.de -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 488 bytes Desc: OpenPGP digital signature URL: