board: verdin-am62: allow dfu update

Detect if U-Boot proper was booted from DFU, if so start DFU for
flashing U-boot to eMMC boot area followed by UMS for flashing eMMC
user area.

Upstream-Status: Pending

Initial U-Boot to be used for bring-up and validation of the V1.0
design, we'll decide on the step forward to mainline this once the
bring-up and validation will be done.

Refactoring ideas:

- `Detect DFU boot` moved into arch K3 specific code.
- `Detect DFU boot` by DFUing to a 'DFU' address a magic pattern
  and test that address.
- Have a special U-Boot configuration for DFU boots,.

- With TEZI available for Verdin AM62 this commit can be dropped.
- The TEZI U-Boot could then have in its boot flow:
...
if (! dfu_boot())
	load_the_TEZI_fitimage_from_eMMC();
boot_from_fitimage();
...

Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>

1 files changed, 48 insertions, 0 deletions

diff --git a/board/toradex/verdin-am62/verdin-am62.c b/board/toradex/verdin-am62/verdin-am62.c
index 7116bd82bc..f1c0614e07 100644
--- a/board/toradex/verdin-am62/verdin-am62.c
+++ b/board/toradex/verdin-am62/verdin-am62.c
@@ -22,6 +22,15 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+/* from 5.8 Boot Memory Maps */
+#define BOOT_PARAMETER_TABLE 0x43c3f298
+/* from 5.6.1 Common Header */
+#define BOOT_PARAMETER_PRIMARY_PERIPHERAL (*(u16 *)(BOOT_PARAMETER_TABLE + 0x04))
+#define BOOT_PARAMETER_SECONDARY_PERIPHERAL (*(u16 *)(BOOT_PARAMETER_TABLE + 0x204))
+#define BOOT_PARAMETER_EMMC 101
+#define BOOT_PARAMETER_SD 100
+#define BOOT_PARAMETER_USB_DFU 70
+
 #define PMIC_I2C_BUS		0x0
 #define PMIC_I2C_ADDRESS	0x30
 #define PMIC_BUCK1_VSET_850	0xa
@@ -126,6 +135,42 @@ int ft_board_setup(void *blob, struct bd_info *bd)
 }
 #endif
 
+#if !defined(CONFIG_SPL_BUILD)
+/* Should check if we were booted over dfu, and if so go to DFU / UMS for download */
+void decide_on_dfu(void)
+{
+	/*
+	 * SD boot with sdcard,		7000f290: 00000000
+	 * SD boot without sdcard, dfu,	7000f290: 00000001
+	 * eMMC Boot, eMMC flashed	7000f290: 00000000
+	 * eMMC Boot, eMMC zeroed	7000f290: 00000001
+	 * DFU Boot			7000f290: 00000000
+	 *
+	 * If this Memory location will stay untouched in future versions is
+	 * unknown, so the code might break.
+	 * Compare with arch/arm/mach-k3/am625_init.c which however is SPL only
+	 */
+	u32 bootindex = *(u32 *)(CONFIG_SYS_K3_BOOT_PARAM_TABLE_INDEX);
+	u32 bootmode = bootindex & 1 ? BOOT_PARAMETER_SECONDARY_PERIPHERAL :
+				       BOOT_PARAMETER_PRIMARY_PERIPHERAL;
+
+	if (bootmode == BOOT_PARAMETER_USB_DFU) {
+		printf("DFU boot mode detected, going to DFU again for further downloads\n");
+		env_set("bootcmd", "setenv dfu_alt_info $dfu_alt_info_emmc;"
+				   "dfu 0 mmc 0; ums 0 mmc 0");
+	}
+
+	debug("Booting from %s boot device\n", bootindex & 1 ? "Secondary" :
+							       "Primary");
+	debug("Primary boot device as read from boot parameters %hd\n",
+	      BOOT_PARAMETER_PRIMARY_PERIPHERAL);
+	debug("Secondary boot device as read from boot parameters %hd\n",
+	      BOOT_PARAMETER_SECONDARY_PERIPHERAL);
+}
+#else
+void decide_on_dfu(void) {}
+#endif /* CONFIG_SPL_BUILD */
+
 static void select_dt_from_module_version(void)
 {
 	char variant[32];
@@ -155,6 +200,9 @@ int board_late_init(void)
 {
 	select_dt_from_module_version();
 
+	/* set bootcmd to start DFU and then UMS mode if booted from DFU */
+	decide_on_dfu();
+
 	return 0;
 }