[PATCH v3 4/8] mach-snapdragon: implement capsule update support

[Ilias Apalodimas]

Hi Caleb,

On Mon, 3 Jun 2024 at 15:49, Caleb Connolly <caleb.connolly at linaro.org> wrote:
>
> Qualcomm boards flash U-Boot to the boot partition, implement support
> for determining which slot U-Boot is running from and finding the
> correct boot partition for that slot and configuring the appropriate DFU
> string.
>
> For now this only supports boards with SCSI/UFS storage where U-Boot is
> flashed to the boot partition, and only U-Boot itself is updated. In the
> future we may also support updating additional firmware components (tz,
> hyp, xbl) as well as having U-Boot installed to other partitions (e.g.
> as a first-stage bootloader).
>
> Signed-off-by: Caleb Connolly <caleb.connolly at linaro.org>
> ---
>  arch/arm/mach-snapdragon/Makefile         |   1 +
>  arch/arm/mach-snapdragon/board.c          |   3 +
>  arch/arm/mach-snapdragon/capsule_update.c | 147 ++++++++++++++++++++++++++++++
>  arch/arm/mach-snapdragon/qcom-priv.h      |   6 ++
>  include/configs/qcom.h                    |   5 +
>  5 files changed, 162 insertions(+)
>
> diff --git a/arch/arm/mach-snapdragon/Makefile b/arch/arm/mach-snapdragon/Makefile
> index 7a4495c8108f..343e825c6fdd 100644
> --- a/arch/arm/mach-snapdragon/Makefile
> +++ b/arch/arm/mach-snapdragon/Makefile
> @@ -2,5 +2,6 @@
>  #
>  # (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski at gmail.com>
>
>  obj-y += board.o
> +obj-$(CONFIG_EFI_HAVE_CAPSULE_SUPPORT) += capsule_update.o
>  obj-$(CONFIG_OF_LIVE) += of_fixup.o
> diff --git a/arch/arm/mach-snapdragon/board.c b/arch/arm/mach-snapdragon/board.c
> index b439a19ec7eb..c4a3394706e6 100644
> --- a/arch/arm/mach-snapdragon/board.c
> +++ b/arch/arm/mach-snapdragon/board.c
> @@ -299,8 +299,11 @@ int board_late_init(void)
>
>         configure_env();
>         qcom_late_init();
>
> +       /* Configure the dfu_string for capsule updates */
> +       qcom_configure_capsule_updates();
> +
>         return 0;
>  }
>
>  static void build_mem_map(void)
> diff --git a/arch/arm/mach-snapdragon/capsule_update.c b/arch/arm/mach-snapdragon/capsule_update.c
> new file mode 100644
> index 000000000000..505f5bf5ae07
> --- /dev/null
> +++ b/arch/arm/mach-snapdragon/capsule_update.c
> @@ -0,0 +1,147 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Common initialisation for Qualcomm Snapdragon boards.

initialization

> + *
> + * Copyright (c) 2024 Linaro Ltd.
> + * Author: Caleb Connolly <caleb.connolly at linaro.org>
> + */
> +
> +#define pr_fmt(fmt) "QCOM-FMP: " fmt
> +
> +#include <dm/device.h>
> +#include <dm/uclass.h>
> +#include <efi.h>
> +#include <efi_loader.h>
> +#include <malloc.h>
> +#include <scsi.h>
> +#include <part.h>
> +#include <linux/err.h>
> +
> +#include "qcom-priv.h"
> +
> +struct efi_fw_image fw_images[] = {
> +       {
> +               .image_type_id = QUALCOMM_UBOOT_BOOT_IMAGE_GUID,
> +               .fw_name = u"QUALCOMM-UBOOT",
> +               .image_index = 1,
> +       },
> +};
> +
> +struct efi_capsule_update_info update_info = {
> +       /* Filled in by configure_dfu_string() */
> +       .dfu_string = NULL,
> +       .num_images = ARRAY_SIZE(fw_images),
> +       .images = fw_images,
> +};
> +
> +/* LSB first */
> +struct part_slot_status {
> +       u16: 2;
> +       u16 active : 1;
> +       u16: 3;
> +       u16 successful : 1;
> +       u16 unbootable : 1;
> +       u16 tries_remaining : 4;
> +};

This is part of their first-stage boot loader and can't change right?

[...]

> +/**
> + * qcom_configure_capsule_updates() - Configure the DFU string for capsule updates
> + *
> + * U-Boot is flashed to the boot partition on Qualcomm boards. In most cases there
> + * are two boot partitions, boot_a and boot_b. As we don't currently support doing
> + * full A/B updates, we only support updating the currently active boot partition.
> + *
> + * So we need to find the current slot suffix and the associated boot partition.
> + * We do this by looking for the boot partition that has the 'active' flag set
> + * in the GPT partition vendor attribute bits.
> + */
> +void qcom_configure_capsule_updates(void)
> +{
> +       struct blk_desc *desc;
> +       int ret = 0, partnum = -1, devnum;
> +       static char dfu_string[32] = { 0 };

Use PART_NAME_LEN here, since that's the length struct disk_partition
defines (and the one you end up copying)

> +       char name[32]; /* GPT partition name */
> +       char *partname = "boot";
> +       struct udevice *dev = NULL;
> +
> +       /*
> +        * There is currently no good way to check how U-Boot is booting, but we have
> +        * a few hueristics, like here checking if our DTB has a kaslr-seed specified

heuristics

> +        * will tell us if we were chainloaded by another bootloader.
> +        * FIXME: we should do this check once and use some proper API to expose the data.
> +        */
> +       if (!ofnode_has_property(ofnode_path("/chosen"), "kaslr-seed")) {

[...]

Acked-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>