riscv: sifive: fu540: add SPL configuration

Add a support for SPL which will boot from L2 LIM (0x0800_0000) and
then SPL will boot U-Boot FIT image (OpenSBI FW_DYNAMIC + u-boot.bin)
from MMC boot devices.

SPL related code is leveraged from FSBL
(https://github.com/sifive/freedom-u540-c000-bootloader.git)

Signed-off-by: Pragnesh Patel <pragnesh.patel@sifive.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com>

arch/riscv/cpu/fu540/Makefile

@@ -3,5 +3,9 @@
 # Copyright (C) 2020 SiFive, Inc
 # Pragnesh Patel <pragnesh.patel@sifive.com>
 
+ifeq ($(CONFIG_SPL_BUILD),y)
+obj-y += spl.o
+else
 obj-y += dram.o
 obj-y += cpu.o
+endif

arch/riscv/cpu/fu540/spl.c

@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 SiFive, Inc
+ * Pragnesh Patel <pragnesh.patel@sifive.com>
+ */
+
+#include <dm.h>
+#include <log.h>
+
+int soc_spl_init(void)
+{
+	int ret;
+	struct udevice *dev;
+
+	/* DDR init */
+	ret = uclass_get_device(UCLASS_RAM, 0, &dev);
+	if (ret) {
+		debug("DRAM init failed: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}

arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi

@@ -4,6 +4,7 @@
  */
 
 #include "fu540-c000-u-boot.dtsi"
+#include "fu540-hifive-unleashed-a00-ddr.dtsi"
 
 / {
 	aliases {
@@ -26,3 +27,7 @@
 		u-boot,dm-spl;
 	};
 };
+
+&gpio {
+	u-boot,dm-spl;
+};

arch/riscv/include/asm/arch-fu540/spl.h

@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2020 SiFive, Inc.
+ *
+ * Authors:
+ *   Pragnesh Patel <pragnesh.patel@sifve.com>
+ */
+
+#ifndef _SPL_SIFIVE_H
+#define _SPL_SIFIVE_H
+
+int soc_spl_init(void);
+
+#endif /* _SPL_SIFIVE_H */

board/sifive/fu540/Kconfig

@@ -13,12 +13,20 @@ config SYS_CONFIG_NAME
 	default "sifive-fu540"
 
 config SYS_TEXT_BASE
+	default 0x80200000 if SPL
 	default 0x80000000 if !RISCV_SMODE
 	default 0x80200000 if RISCV_SMODE
 
+config SPL_TEXT_BASE
+	default 0x08000000
+
+config SPL_OPENSBI_LOAD_ADDR
+	default 0x80000000
+
 config BOARD_SPECIFIC_OPTIONS # dummy
 	def_bool y
-	select GENERIC_RISCV
+	select SIFIVE_FU540
+	select SUPPORT_SPL
 	select RAM
 	select SPL_RAM if SPL
 	imply CMD_DHCP

board/sifive/fu540/Makefile

@@ -3,3 +3,7 @@
 # Copyright (c) 2019 Western Digital Corporation or its affiliates.
 
 obj-y	+= fu540.o
+
+ifdef CONFIG_SPL_BUILD
+obj-y += spl.o
+endif

board/sifive/fu540/fu540.c

@@ -14,6 +14,7 @@
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <misc.h>
+#include <spl.h>
 
 /*
  * This define is a value used for error/unknown serial.
@@ -117,3 +118,23 @@ int board_init(void)
 
 	return 0;
 }
+
+#ifdef CONFIG_SPL
+u32 spl_boot_device(void)
+{
+#ifdef CONFIG_SPL_MMC_SUPPORT
+	return BOOT_DEVICE_MMC1;
+#else
+	puts("Unknown boot device\n");
+	hang();
+#endif
+}
+#endif
+
+#ifdef CONFIG_SPL_LOAD_FIT
+int board_fit_config_name_match(const char *name)
+{
+	/* boot using first FIT config */
+	return 0;
+}
+#endif

board/sifive/fu540/spl.c

@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2019 SiFive, Inc
+ *
+ * Authors:
+ *   Pragnesh Patel <pragnesh.patel@sifive.com>
+ */
+
+#include <init.h>
+#include <spl.h>
+#include <misc.h>
+#include <log.h>
+#include <linux/delay.h>
+#include <asm/gpio.h>
+#include <asm/arch/gpio.h>
+#include <asm/arch/spl.h>
+
+#define GEM_PHY_RESET	SIFIVE_GENERIC_GPIO_NR(0, 12)
+
+int init_clk_and_ddr(void)
+{
+	int ret;
+
+	ret = soc_spl_init();
+	if (ret) {
+		debug("FU540 SPL init failed: %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * GEMGXL init VSC8541 PHY reset sequence;
+	 * leave pull-down active for 2ms
+	 */
+	udelay(2000);
+	ret = gpio_request(GEM_PHY_RESET, "gem_phy_reset");
+	if (ret) {
+		debug("gem_phy_reset gpio request failed: %d\n", ret);
+		return ret;
+	}
+
+	/* Set GPIO 12 (PHY NRESET) */
+	ret = gpio_direction_output(GEM_PHY_RESET, 1);
+	if (ret) {
+		debug("gem_phy_reset gpio direction set failed: %d\n", ret);
+		return ret;
+	}
+
+	udelay(1);
+
+	/* Reset PHY again to enter unmanaged mode */
+	gpio_set_value(GEM_PHY_RESET, 0);
+	udelay(1);
+	gpio_set_value(GEM_PHY_RESET, 1);
+	mdelay(15);
+
+	return 0;
+}
+
+void board_init_f(ulong dummy)
+{
+	int ret;
+
+	ret = spl_early_init();
+	if (ret)
+		panic("spl_early_init() failed: %d\n", ret);
+
+	arch_cpu_init_dm();
+
+	preloader_console_init();
+
+	ret = init_clk_and_ddr();
+	if (ret)
+		panic("init_clk_and_ddr() failed: %d\n", ret);
+}

include/configs/sifive-fu540.h

@@ -11,6 +11,22 @@
 
 #include <linux/sizes.h>
 
+#ifdef CONFIG_SPL
+
+#define CONFIG_SPL_MAX_SIZE		0x00100000
+#define CONFIG_SPL_BSS_START_ADDR	0x85000000
+#define CONFIG_SPL_BSS_MAX_SIZE		0x00100000
+#define CONFIG_SYS_SPL_MALLOC_START	(CONFIG_SPL_BSS_START_ADDR + \
+					 CONFIG_SPL_BSS_MAX_SIZE)
+#define CONFIG_SYS_SPL_MALLOC_SIZE	0x00100000
+
+#define CONFIG_SPL_LOAD_FIT_ADDRESS	0x84000000
+
+#define CONFIG_SPL_STACK	(0x08000000 + 0x001D0000 - \
+				 GENERATED_GBL_DATA_SIZE)
+
+#endif
+
 #define CONFIG_SYS_SDRAM_BASE		0x80000000
 #define CONFIG_SYS_INIT_SP_ADDR		(CONFIG_SYS_SDRAM_BASE + SZ_2M)
 
@@ -24,6 +40,7 @@
 
 /* Environment options */
 
+#ifndef CONFIG_SPL_BUILD
 #define BOOT_TARGET_DEVICES(func) \
 	func(MMC, mmc, 0) \
 	func(DHCP, dhcp, na)
@@ -43,5 +60,6 @@
 #define CONFIG_PREBOOT \
 	"setenv fdt_addr ${fdtcontroladdr};" \
 	"fdt addr ${fdtcontroladdr};"
+#endif
 
 #endif /* __CONFIG_H */