[PATCH] board: ti: am43xx: pass boot device information from SPL to U-Boot proper

[Michael Nazzareno Trimarchi]

Hi Josef

On Fri, Nov 26, 2021 at 10:56 AM Josef Lusticky <josef at lusticky.cz> wrote:
>
> TI AM43xx SoC supports various boot devices (peripherals).
> There is already handoff mechanism prepared to allow passing
> the information which boot device was used to load the SPL.
>
> Use the handoff mechanism to pass this information to U-Boot proper
> and set the "boot_device" environment variable in board_late_init.
>
> Signed-off-by: Josef Lusticky <josef at lusticky.cz>
> Cc: Tom Rini <trini at konsulko.com>
> Cc: Lokesh Vutla <lokeshvutla at ti.com>
> Cc: Michael Trimarchi <michael at amarulasolutions.com>
> ---
>
> I use the boot_device variable later in U-Boot scripting - e.g. to avoid running
> bootcmd when the SPL was loaded from UART but run it when loaded from MMC.
> Only AM43xx is supported by this patch, but for other TI SoCs
> the procedure should be the same:
> - figure out supported boot devices from arch/arm/include/asm/arch-am33xx/spl.h
> or arch/arm/include/asm/arch-omapX/spl.h
> - implement setting the boot_device env variable in board_late_init()
>
> You'll need to enable the following in the config:
> CONFIG_BLOBLIST=y (required by CONFIG_HANDOFF)
> CONFIG_HANDOFF=y
> CONFIG_BLOBLIST_ADDR=0x87000000 (i set this based on other values defined by
> the DEFAULT_LINUX_BOOT_ENV macro in include/configs/ti_armv7_common.h, you
> may want to use a different address)
>
>  arch/arm/include/asm/handoff.h    |  3 +++
>  arch/arm/mach-omap2/boot-common.c |  9 ++++++++
>  board/ti/am43xx/board.c           | 38 +++++++++++++++++++++++++++++++
>  3 files changed, 50 insertions(+)
>
> diff --git a/arch/arm/include/asm/handoff.h b/arch/arm/include/asm/handoff.h
> index 0790d2ab1e..1b7aa432a2 100644
> --- a/arch/arm/include/asm/handoff.h
> +++ b/arch/arm/include/asm/handoff.h
> @@ -16,6 +16,9 @@
>   */
>  struct arch_spl_handoff {
>         ulong usable_ram_top;
> +#ifdef CONFIG_ARCH_OMAP2PLUS
> +       u32 omap_boot_device;
> +#endif
>  };

Simon is working on a more structured way to pass arguments in
multi-stage boot. I forget to read all the patches.
Anyway adding a specific handoff parameter for one architecture makes
no such sense. I will remind you that this
was already implemented in the past using dts injection (something
that I don't  like)

Michael

>
>  #endif
> diff --git a/arch/arm/mach-omap2/boot-common.c b/arch/arm/mach-omap2/boot-common.c
> index 1268a32503..191bb2a42d 100644
> --- a/arch/arm/mach-omap2/boot-common.c
> +++ b/arch/arm/mach-omap2/boot-common.c
> @@ -236,3 +236,12 @@ void arch_preboot_os(void)
>         ahci_reset((void __iomem *)DWC_AHSATA_BASE);
>  }
>  #endif
> +
> +#if CONFIG_IS_ENABLED(HANDOFF)
> +int handoff_arch_save(struct spl_handoff *ho)
> +{
> +       ho->arch.omap_boot_device = spl_boot_device();
> +
> +       return 0;
> +}
> +#endif
> diff --git a/board/ti/am43xx/board.c b/board/ti/am43xx/board.c
> index a71b588efc..8c5834fc25 100644
> --- a/board/ti/am43xx/board.c
> +++ b/board/ti/am43xx/board.c
> @@ -726,6 +726,44 @@ static int device_okay(const char *path)
>  int board_late_init(void)
>  {
>         struct udevice *dev;
> +
> +#if CONFIG_IS_ENABLED(HANDOFF)
> +       /* Read peripheral SPL was loaded from */
> +       if (gd->spl_handoff) {
> +               switch (gd->spl_handoff->arch.omap_boot_device) {
> +               case BOOT_DEVICE_CPGMAC:
> +                       env_set("boot_device", "cpgmac");
> +                       break;
> +               case BOOT_DEVICE_MMC1:
> +                       env_set("boot_device", "mmc1");
> +                       break;
> +               case BOOT_DEVICE_MMC2:
> +                       env_set("boot_device", "mmc2");
> +                       break;
> +               case BOOT_DEVICE_NAND:
> +                       env_set("boot_device", "nand");
> +                       break;
> +               case BOOT_DEVICE_NOR:
> +                       env_set("boot_device", "nor");
> +                       break;
> +               case BOOT_DEVICE_SPI:
> +                       env_set("boot_device", "spi");
> +                       break;
> +               case BOOT_DEVICE_UART:
> +                       env_set("boot_device", "uart");
> +                       break;
> +               case BOOT_DEVICE_USB:
> +                       env_set("boot_device", "usb");
> +                       break;
> +               case BOOT_DEVICE_USBETH:
> +                       env_set("boot_device", "usbeth");
> +                       break;
> +               default:
> +                       env_set("boot_device", "unknown");
> +               }
> +       }
> +#endif
> +
>  #ifdef CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
>         set_board_info_env(NULL);
>
> --
> 2.30.2
>


-- 
Michael Nazzareno Trimarchi
Co-Founder & Chief Executive Officer
M. +39 347 913 2170
michael at amarulasolutions.com
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