Re: [PATCH 1/4] mach-snapdragon: track boot source

[Neil Armstrong]

On 26/03/2025 18:40, Caleb Connolly wrote:

Keep track of whether we were loaded via ABL or if U-Boot is running as
a first-stage bootloader.

For now we set this based on if we have a valid external FDT or not,
since it isn't possible to chainload U-Boot from ABL without there being
an external FDT.

This will be used to inform the capsule update logic which partition
U-Boot is flashed to.

Signed-off-by: Caleb Connolly <caleb.conno...@linaro.org>
---
  arch/arm/mach-snapdragon/board.c     | 25 +++++++++++++++++++++++++
  arch/arm/mach-snapdragon/qcom-priv.h | 14 ++++++++++++++
  2 files changed, 39 insertions(+)

diff --git a/arch/arm/mach-snapdragon/board.c b/arch/arm/mach-snapdragon/board.c
index 
deae4d323789eab75d5fe735159b4cd820c02c45..245a963f5321bda3030d3809e1b108f280b3c2b5
 100644
--- a/arch/arm/mach-snapdragon/board.c
+++ b/arch/arm/mach-snapdragon/board.c
@@ -36,8 +36,10 @@
  #include "qcom-priv.h"

DECLARE_GLOBAL_DATA_PTR; +enum qcom_boot_source qcom_boot_source __section(".data") = 0;

+
  static struct mm_region rbx_mem_map[CONFIG_NR_DRAM_BANKS + 2] = { { 0 } };

struct mm_region *mem_map = rbx_mem_map; @@ -237,8 +239,14 @@ int board_fdt_blob_setup(void **fdtp) if (ret < 0)

                panic("No valid memory ranges found!\n");

+ /* If we have an external FDT, it can only have come from the Android bootloader. */

+       if (external_valid)
+               qcom_boot_source = QCOM_BOOT_SOURCE_ANDROID;
+       else
+               qcom_boot_source = QCOM_BOOT_SOURCE_XBL;
+
        debug("ram_base = %#011lx, ram_size = %#011llx\n",
              gd->ram_base, gd->ram_size);

if (internal_valid) {

@@ -472,8 +480,24 @@ static void configure_env(void)

qcom_set_serialno();

  }

+void qcom_show_boot_source(void)

+{
+       const char *name = "UNKNOWN";
+
+       switch (qcom_boot_source) {
+       case QCOM_BOOT_SOURCE_ANDROID:
+               name = "ABL";
+               break;
+       case QCOM_BOOT_SOURCE_XBL:
+               name = "XBL";
+               break;
+       }
+
+       log_info("U-Boot loaded from %s\n", name);

Can you write to a boot_source env variable ?

+}
+
  void __weak qcom_late_init(void)
  {
  }

@@ -515,8 +539,9 @@ int board_late_init(void) configure_env();

        qcom_late_init();

+ qcom_show_boot_source();

        /* Configure the dfu_string for capsule updates */
        qcom_configure_capsule_updates();

return 0;

diff --git a/arch/arm/mach-snapdragon/qcom-priv.h 
b/arch/arm/mach-snapdragon/qcom-priv.h
index 
74d39197b89f4e769299b06214c26ee829ecdce0..e5eb4cfbc2b752de799b1407ede69683c81474c1
 100644
--- a/arch/arm/mach-snapdragon/qcom-priv.h
+++ b/arch/arm/mach-snapdragon/qcom-priv.h
@@ -2,8 +2,22 @@

#ifndef __QCOM_PRIV_H__

  #define __QCOM_PRIV_H__

+/**

+ * enum qcom_boot_source - Track where we got loaded from.
+ * Used for capsule update logic.
+ *
+ * @QCOM_BOOT_SOURCE_ANDROID: chainloaded (typically from ABL)
+ * @QCOM_BOOT_SOURCE_XBL: flashed to the XBL or UEFI partition
+ */
+enum qcom_boot_source {
+       QCOM_BOOT_SOURCE_ANDROID = 1,
+       QCOM_BOOT_SOURCE_XBL,
+};
+
+extern enum qcom_boot_source qcom_boot_source;
+
  #if IS_ENABLED(CONFIG_EFI_HAVE_CAPSULE_SUPPORT)
  void qcom_configure_capsule_updates(void);
  #else
  void qcom_configure_capsule_updates(void) {}