[PATCH 3/7] rockchip: px30: insert u-boot, spl-boot-device into U-Boot device tree

[Quentin Schulz]

From: Quentin Schulz <quentin.schulz at theobroma-systems.com>

It is possible to boot U-Boot proper from a different storage medium
than the one used by the BOOTROM to load the SPL. This information is
stored in the u-boot,spl-boot-device Device Tree property and is
accessible from U-Boot proper so that it has knowledge at runtime where
it was loaded from.

Let's add support for this feature for px30.

Cc: Quentin Schulz <foss+uboot at 0leil.net>
Signed-off-by: Quentin Schulz <quentin.schulz at theobroma-systems.com>
---
 arch/arm/mach-rockchip/px30/px30.c | 50 ++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)

diff --git a/arch/arm/mach-rockchip/px30/px30.c b/arch/arm/mach-rockchip/px30/px30.c
index 481b50235e..5f26128d01 100644
--- a/arch/arm/mach-rockchip/px30/px30.c
+++ b/arch/arm/mach-rockchip/px30/px30.c
@@ -6,6 +6,7 @@
 #include <clk.h>
 #include <dm.h>
 #include <init.h>
+#include <spl.h>
 #include <asm/armv8/mmu.h>
 #include <asm/io.h>
 #include <asm/arch-rockchip/bootrom.h>
@@ -427,3 +428,52 @@ void board_debug_uart_init(void)
 #endif /* CONFIG_DEBUG_UART_BASE && CONFIG_DEBUG_UART_BASE == ... */
 }
 #endif /* CONFIG_DEBUG_UART_BOARD_INIT */
+
+#if defined(CONFIG_SPL_BUILD) && !defined(CONFIG_TPL_BUILD)
+const char *spl_decode_boot_device(u32 boot_device)
+{
+	int i;
+	static const struct {
+		u32 boot_device;
+		const char *ofpath;
+	} spl_boot_devices_tbl[] = {
+		{ BOOT_DEVICE_MMC2, "/mmc at ff370000" },
+		{ BOOT_DEVICE_MMC1, "/mmc at ff390000" },
+	};
+
+	for (i = 0; i < ARRAY_SIZE(spl_boot_devices_tbl); ++i)
+		if (spl_boot_devices_tbl[i].boot_device == boot_device)
+			return spl_boot_devices_tbl[i].ofpath;
+
+	return NULL;
+}
+
+void spl_perform_fixups(struct spl_image_info *spl_image)
+{
+	void *blob = spl_image->fdt_addr;
+	const char *boot_ofpath;
+	int chosen;
+
+	/*
+	 * Inject the ofpath of the device the full U-Boot (or Linux in
+	 * Falcon-mode) was booted from into the FDT, if a FDT has been
+	 * loaded at the same time.
+	 */
+	if (!blob)
+		return;
+
+	boot_ofpath = spl_decode_boot_device(spl_image->boot_device);
+	if (!boot_ofpath) {
+		pr_err("%s: could not map boot_device to ofpath\n", __func__);
+		return;
+	}
+
+	chosen = fdt_find_or_add_subnode(blob, 0, "chosen");
+	if (chosen < 0) {
+		pr_err("%s: could not find/create '/chosen'\n", __func__);
+		return;
+	}
+	fdt_setprop_string(blob, chosen,
+			   "u-boot,spl-boot-device", boot_ofpath);
+}
+#endif
-- 
2.37.3