rockchip: add option to change method of loading u-boot

If we would like to boot from SD card, we have to implement mmc driver
in SPL stage, and get a slightly large SPL binary. Rockchip SoC's
bootrom code has the ability to load spl and u-boot, then boot.

If CONFIG_ROCKCHIP_SPL_BACK_TO_BROM is enabled, the spl will return to
bootrom in board_init_f(), then bootrom loads u-boot binary.

Loading sequence after rework:
bootrom ==> spl ==> bootrom ==> u-boot

Signed-off-by: Ziyuan Xu <xzy.xu@rock-chips.com>
Acked-by: Simon Glass <sjg@chromium.org>
Fixed up spelling of U-Boot, boorom, opinion->option, Rochchip:
Signed-off-by: Simon Glass <sjg@chromium.org>

6 files changed, 47 insertions, 3 deletions

diff --git a/arch/arm/mach-rockchip/Kconfig b/arch/arm/mach-rockchip/Kconfig
index c49cc19be3..cf718fab57 100644
--- a/arch/arm/mach-rockchip/Kconfig
+++ b/arch/arm/mach-rockchip/Kconfig
@@ -17,6 +17,14 @@ config ROCKCHIP_RK3036
 	  and video codec support. Peripherals include Gigabit Ethernet,
 	  USB2 host and OTG, SDIO, I2S, UART, SPI, I2C and PWMs.
 
+config ROCKCHIP_SPL_BACK_TO_BROM
+	bool "SPL returns to bootrom"
+	default y if ROCKCHIP_RK3036
+	help
+	  Rockchip SoCs have ability to load SPL & U-Boot binary. If enabled,
+          SPL will return to the boot rom, which will then load the U-Boot
+          binary to keep going on.
+
 source "arch/arm/mach-rockchip/rk3288/Kconfig"
 source "arch/arm/mach-rockchip/rk3036/Kconfig"
 endif
diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
index 55567cb131..c08d61bb11 100644
--- a/arch/arm/mach-rockchip/Makefile
+++ b/arch/arm/mach-rockchip/Makefile
@@ -7,6 +7,7 @@
 ifdef CONFIG_SPL_BUILD
 obj-$(CONFIG_ROCKCHIP_RK3288) += rk3288-board-spl.o
 obj-$(CONFIG_ROCKCHIP_RK3036) += rk3036-board-spl.o
+obj-$(CONFIG_ROCKCHIP_SPL_BACK_TO_BROM) += save_boot_param.o
 else
 obj-$(CONFIG_ROCKCHIP_RK3288) += board.o
 endif
diff --git a/arch/arm/mach-rockchip/board.c b/arch/arm/mach-rockchip/board.c
index 816540e582..b07e0738ea 100644
--- a/arch/arm/mach-rockchip/board.c
+++ b/arch/arm/mach-rockchip/board.c
@@ -10,12 +10,45 @@
 #include <ram.h>
 #include <asm/io.h>
 #include <asm/arch/clock.h>
+#include <asm/arch/periph.h>
+#include <asm/gpio.h>
+#include <dm/pinctrl.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
 int board_init(void)
 {
+#ifdef CONFIG_ROCKCHIP_SPL_BACK_TO_BROM
+	struct udevice *pinctrl;
+	int ret;
+
+    /*
+     * We need to implement sdcard iomux here for the further
+     * initlization, otherwise, it'll hit sdcard command sending
+     * timeout exception.
+     */
+	ret = uclass_get_device(UCLASS_PINCTRL, 0, &pinctrl);
+	if (ret) {
+		debug("%s: Cannot find pinctrl device\n", __func__);
+		goto err;
+	}
+	ret = pinctrl_request_noflags(pinctrl, PERIPH_ID_SDCARD);
+	if (ret) {
+		debug("%s: Failed to set up SD card\n", __func__);
+		goto err;
+	}
+
+	return 0;
+err:
+	printf("board_init: Error %d\n", ret);
+
+	/* No way to report error here */
+	hang();
+
+	return -1;
+#else
 	return 0;
+#endif
 }
 
 int dram_init(void)
diff --git a/arch/arm/mach-rockchip/rk3036/Makefile b/arch/arm/mach-rockchip/rk3036/Makefile
index 97d299d6cc..6095777b8f 100644
--- a/arch/arm/mach-rockchip/rk3036/Makefile
+++ b/arch/arm/mach-rockchip/rk3036/Makefile
@@ -10,4 +10,3 @@ obj-y += syscon_rk3036.o
 endif
 
 obj-y += sdram_rk3036.o
-obj-y += save_boot_param.o
diff --git a/arch/arm/mach-rockchip/rk3288-board-spl.c b/arch/arm/mach-rockchip/rk3288-board-spl.c
index 123f58b27f..08152aa72b 100644
--- a/arch/arm/mach-rockchip/rk3288-board-spl.c
+++ b/arch/arm/mach-rockchip/rk3288-board-spl.c
@@ -149,7 +149,7 @@ static int configure_emmc(struct udevice *pinctrl)
 	return 0;
 }
 #endif
-
+extern void back_to_bootrom(void);
 void board_init_f(ulong dummy)
 {
 	struct udevice *pinctrl;
@@ -204,6 +204,9 @@ void board_init_f(ulong dummy)
 		debug("DRAM init failed: %d\n", ret);
 		return;
 	}
+#ifdef CONFIG_ROCKCHIP_SPL_BACK_TO_BROM
+	back_to_bootrom();
+#endif
 }
 
 static int setup_led(void)
diff --git a/arch/arm/mach-rockchip/rk3036/save_boot_param.S b/arch/arm/mach-rockchip/save_boot_param.S
index 778ec83c2c..85b407b4d3 100644
--- a/arch/arm/mach-rockchip/rk3036/save_boot_param.S
+++ b/arch/arm/mach-rockchip/save_boot_param.S
@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2015 Google, Inc
+ * (C) Copyright 2016 Rockchip Electronics Co., Ltd
  *
  * SPDX-License-Identifier:     GPL-2.0+
  */