ARM64: zynqmp: Add SPL support support

Support RAM and MMC boot mode in SPL also with SPL_FIT images.

In MMC boot mode two boot options are available:
1) Boot flow with ATF(EL3) and full U-Boot(EL2):
 aarch64-linux-gnu-objcopy -O binary bl31.elf bl31.bin
 mkimage -A arm64 -O linux -T kernel -C none -a 0xfffe5000 -e 0xfffe5000
 -d bl31.bin atf.ub
 cp spl/boot.bin <sdcard fat partition>
 cp atf.ub <sdcard fat partition>
 cp u-boot.bin <sdcard fat partition>

2) Boot flow with full U-Boot(EL3):
 cp spl/boot.bin <sdcard>
 cp u-boot*.img <sdcard>

3) emmc boot mode
 dd if=/dev/zero of=sd.img bs=1024 count=1024
 parted sd.img mktable msdos
 parted sd.img mkpart p fat32 0% 100%
 kpartx -a sd.img
 mkfs.vfat /dev/mapper/loop0p1
 mount /dev/mapper/loop0p1 /mnt/
 cp spl/boot.bin /mnt
 cp u-boot.img /mnt
 cp u-boot.bin /mnt
 cp atf.ub /mnt
 umount /dev/mapper/loop0p1
 kpartx -d sd.img
 cp sd.img /tftpboot/

 and program it via u-boot
 tftpb 10000 sd.img
 mmcinfo
 mmc write 10000 0 $filesize
 mmc rescan
 mmc part
 ls mmc 0

psu_init() function contains low level SoC setup generated for every HW
design by Xilinx design tools. xil_io.h is only supporting file to fix
all dependencies from tools. The same solution was used on Xilinx Zynq.

The patch also change CONFIG_SYS_INIT_SP_ADDR to the end of OCM which
stays at the same location all the time.
Bootrom expects starting address to be at 0xfffc0000 that's why this
address is SPL_TEXT_BASE.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

arch/arm/Kconfig

@@ -594,6 +594,7 @@ config ARCH_ZYNQMP
 	select DM
 	select OF_CONTROL
 	select DM_SERIAL
+	select SUPPORT_SPL
 
 config TEGRA
 	bool "NVIDIA Tegra"

arch/arm/cpu/armv8/zynqmp/Makefile

@@ -9,3 +9,4 @@ obj-y	+= clk.o
 obj-y	+= cpu.o
 obj-$(CONFIG_MP)	+= mp.o
 obj-y	+= slcr.o
+obj-$(CONFIG_SPL_BUILD) += spl.o

arch/arm/cpu/armv8/zynqmp/spl.c

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2015 - 2016 Xilinx, Inc.
+ *
+ * Michal Simek <michal.simek@xilinx.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <debug_uart.h>
+#include <spl.h>
+
+#include <asm/io.h>
+#include <asm/spl.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/sys_proto.h>
+
+void board_init_f(ulong dummy)
+{
+	psu_init();
+	board_early_init_r();
+
+#ifdef CONFIG_DEBUG_UART
+	/* Uart debug for sure */
+	debug_uart_init();
+	puts("Debug uart enabled\n"); /* or printch() */
+#endif
+	/* Delay is required for clocks to be propagated */
+	udelay(1000000);
+
+	/* Clear the BSS */
+	memset(__bss_start, 0, __bss_end - __bss_start);
+
+	/* No need to call timer init - it is empty for ZynqMP */
+	board_init_r(NULL, 0);
+}
+
+#ifdef CONFIG_SPL_BOARD_INIT
+void spl_board_init(void)
+{
+	preloader_console_init();
+	board_init();
+}
+#endif
+
+u32 spl_boot_device(void)
+{
+	u32 reg = 0;
+	u8 bootmode;
+
+	reg = readl(&crlapb_base->boot_mode);
+	bootmode = reg & BOOT_MODES_MASK;
+
+	switch (bootmode) {
+	case JTAG_MODE:
+		return BOOT_DEVICE_RAM;
+#ifdef CONFIG_SPL_MMC_SUPPORT
+	case EMMC_MODE:
+	case SD_MODE:
+	case SD_MODE1:
+		return BOOT_DEVICE_MMC1;
+#endif
+	default:
+		printf("Invalid Boot Mode:0x%x\n", bootmode);
+		break;
+	}
+
+	return 0;
+}
+
+u32 spl_boot_mode(void)
+{
+	switch (spl_boot_device()) {
+	case BOOT_DEVICE_RAM:
+		return 0;
+	case BOOT_DEVICE_MMC1:
+		return MMCSD_MODE_FS;
+	default:
+		puts("spl: error: unsupported device\n");
+		hang();
+	}
+}
+
+__weak void psu_init(void)
+{
+	 /*
+	  * This function is overridden by the one in
+	  * board/xilinx/zynqmp/(platform)/psu_init_gpl.c, if it exists.
+	  */
+}
+
+#ifdef CONFIG_SPL_OS_BOOT
+int spl_start_uboot(void)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_SPL_LOAD_FIT
+int board_fit_config_name_match(const char *name)
+{
+	/* Just empty function now - can't decide what to choose */
+	debug("%s: %s\n", __func__, name);
+
+	return 0;
+}
+#endif

arch/arm/include/asm/arch-zynqmp/sys_proto.h

@@ -17,4 +17,6 @@ int zynq_slcr_get_mio_pin_status(const char *periph);
 
 unsigned int zynqmp_get_silicon_version(void);
 
+void psu_init(void);
+
 #endif /* _ASM_ARCH_SYS_PROTO_H */