[PATCH 02/10] stm32mp1: Add support for falcon mode boot from SD card

[Alexandru Gagniuc]

Falcon mode requires a board-specific mechanism to select between
fast and normal boot. This is done via spl_start_uboot()

Use the B2 button as the selection mechanism. This is connected to
GPIO PA13. Incidentally, this GPIO is already accessible via the
"st,fastboot-gpios" devicetree node.

Offsets for raw MMC loading are defined. These point to the partition
after "ssbl".

Signed-off-by: Alexandru Gagniuc <mr.nuke.me at gmail.com>
---
 board/st/stm32mp1/spl.c    | 39 ++++++++++++++++++++++++++++++++++++++
 include/configs/stm32mp1.h | 13 +++++++++++++
 2 files changed, 52 insertions(+)

diff --git a/board/st/stm32mp1/spl.c b/board/st/stm32mp1/spl.c
index 8e4549a1b3..bb210d7727 100644
--- a/board/st/stm32mp1/spl.c
+++ b/board/st/stm32mp1/spl.c
@@ -8,6 +8,7 @@
 #include <init.h>
 #include <asm/io.h>
 #include <asm/arch/sys_proto.h>
+#include <asm/gpio.h>
 #include <linux/bitops.h>
 #include <linux/delay.h>
 #include "../common/stpmic1.h"
@@ -29,6 +30,44 @@ int board_early_init_f(void)
 	return 0;
 }
 
+#if IS_ENABLED(CONFIG_SPL_OS_BOOT)
+int spl_start_uboot(void)
+{
+	ofnode node;
+	struct gpio_desc gpio;
+	int boot_uboot = 1;
+
+	node = ofnode_path("/config");
+	if (!ofnode_valid(node)) {
+		pr_warn("%s: no /config node?\n", __func__);
+		return 0;
+	}
+
+	if (gpio_request_by_name_nodev(node, "st,fastboot-gpios", 0, &gpio,
+				       GPIOD_IS_IN)) {
+		pr_warn("%s: could not find a /config/st,fastboot-gpios\n",
+			__func__);
+		return 1;
+	}
+
+	boot_uboot = dm_gpio_get_value(&gpio);
+	dm_gpio_free(NULL, &gpio);
+
+	return boot_uboot;
+}
+
+#if IS_ENABLED(CONFIG_ARMV7_NONSEC)
+/*
+ * A bit of a hack, but armv7_boot_nonsec() is provided by bootm.c. This is not
+ * available in SPL, so we have to provide an implementation.
+ */
+bool armv7_boot_nonsec(void)
+{
+	return 0;
+}
+#endif /* CONFIG_ARMV7_NONSEC */
+#endif /* CONFIG_SPL_OS_BOOT */
+
 #ifdef CONFIG_DEBUG_UART_BOARD_INIT
 void board_debug_uart_init(void)
 {
diff --git a/include/configs/stm32mp1.h b/include/configs/stm32mp1.h
index 9fcd60285a..0849a1bddb 100644
--- a/include/configs/stm32mp1.h
+++ b/include/configs/stm32mp1.h
@@ -10,6 +10,19 @@
 #include <linux/sizes.h>
 #include <asm/arch/stm32.h>
 
+/*
+ * Arguments if falcon mode is used
+ * CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR is the partition after "ssbl"
+ * CONFIG_SYS_SPL_ARGS_ADDR is not used, but needs to point to valid RAM.
+ */
+#define CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 5154
+#define CONFIG_SYS_SPL_ARGS_ADDR 0xc4000000
+
+/* Falcon mode from SPI is not supported, but the defines are needed */
+#define CONFIG_SYS_SPI_KERNEL_OFFS	(~0)
+#define CONFIG_SYS_SPI_ARGS_OFFS	(~0)
+#define CONFIG_SYS_SPI_ARGS_SIZE	0
+
 #ifndef CONFIG_TFABOOT
 /* PSCI support */
 #define CONFIG_ARMV7_SECURE_BASE		STM32_SYSRAM_BASE
-- 
2.31.1