[U-Boot] [v4 PATCH] RISCV: image: Add booti support

[Atish Patra <atish.patra@wdc.com>]

This patch adds booti support for RISC-V Linux kernel. The existing
bootm method will also continue to work as it is.

It depends on the following kernel patch which adds the header to the
flat Image. Gzip compressed Image (Image.gz) support is not enabled with
this patch.

https://patchwork.kernel.org/patch/10925543/

Tested on HiFive Unleashed and QEMU.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Tested-by: Karsten Merker <merker@debian.org>
---
Changes from v3->v4
1. Rebased on top of master to avoid git am errors.

Changes from v2->v3
1. Updated the image header structure as per kernel patch.
2. Removed Image.gz support as it will be added as separate RFC patch.
---
 arch/riscv/lib/Makefile |  1 +
 arch/riscv/lib/image.c  | 55 +++++++++++++++++++++++++++++++++++++++++
 cmd/Kconfig             |  2 +-
 cmd/booti.c             |  8 ++++--
 4 files changed, 63 insertions(+), 3 deletions(-)
 create mode 100644 arch/riscv/lib/image.c

diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile
index 1c332db436a9..6ae6ebbeafda 100644
--- a/arch/riscv/lib/Makefile
+++ b/arch/riscv/lib/Makefile
@@ -7,6 +7,7 @@
 # Rick Chen, Andes Technology Corporation <rick@andestech.com>
 
 obj-$(CONFIG_CMD_BOOTM) += bootm.o
+obj-$(CONFIG_CMD_BOOTI) += bootm.o image.o
 obj-$(CONFIG_CMD_GO) += boot.o
 obj-y	+= cache.o
 obj-$(CONFIG_RISCV_RDTIME) += rdtime.o
diff --git a/arch/riscv/lib/image.c b/arch/riscv/lib/image.c
new file mode 100644
index 000000000000..d063beb7dfbe
--- /dev/null
+++ b/arch/riscv/lib/image.c
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ * Authors:
+ *	Atish Patra <atish.patra@wdc.com>
+ * Based on arm/lib/image.c
+ */
+
+#include <common.h>
+#include <mapmem.h>
+#include <errno.h>
+#include <linux/sizes.h>
+#include <linux/stddef.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* ASCII version of "RISCV" defined in Linux kernel */
+#define LINUX_RISCV_IMAGE_MAGIC 0x5643534952
+
+struct linux_image_h {
+	uint32_t	code0;		/* Executable code */
+	uint32_t	code1;		/* Executable code */
+	uint64_t	text_offset;	/* Image load offset */
+	uint64_t	image_size;	/* Effective Image size */
+	uint64_t	res1;		/* reserved */
+	uint64_t	res2;		/* reserved */
+	uint64_t	res3;		/* reserved */
+	uint64_t	magic;		/* Magic number */
+	uint32_t	res4;		/* reserved */
+	uint32_t	res5;		/* reserved */
+};
+
+int booti_setup(ulong image, ulong *relocated_addr, ulong *size,
+		bool force_reloc)
+{
+	struct linux_image_h *lhdr;
+
+	lhdr = (struct linux_image_h *)map_sysmem(image, 0);
+
+	if (lhdr->magic != LINUX_RISCV_IMAGE_MAGIC) {
+		puts("Bad Linux RISCV Image magic!\n");
+		return -EINVAL;
+	}
+
+	if (lhdr->image_size == 0) {
+		puts("Image lacks image_size field, error!\n");
+		return -EINVAL;
+	}
+	*size = lhdr->image_size;
+	*relocated_addr = gd->ram_base + lhdr->text_offset;
+
+	unmap_sysmem(lhdr);
+
+	return 0;
+}
diff --git a/cmd/Kconfig b/cmd/Kconfig
index 069e0ea7300b..4e11e0f404c8 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -223,7 +223,7 @@ config CMD_BOOTZ
 
 config CMD_BOOTI
 	bool "booti"
-	depends on ARM64
+	depends on ARM64 || RISCV
 	default y
 	help
 	  Boot an AArch64 Linux Kernel image from memory.
diff --git a/cmd/booti.c b/cmd/booti.c
index 04353b68eccc..5e902993865b 100644
--- a/cmd/booti.c
+++ b/cmd/booti.c
@@ -77,7 +77,11 @@ int do_booti(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	bootm_disable_interrupts();
 
 	images.os.os = IH_OS_LINUX;
+#ifdef CONFIG_RISCV_SMODE
+	images.os.arch = IH_ARCH_RISCV;
+#elif CONFIG_ARM64
 	images.os.arch = IH_ARCH_ARM64;
+#endif
 	ret = do_bootm_states(cmdtp, flag, argc, argv,
 #ifdef CONFIG_SYS_BOOT_RAMDISK_HIGH
 			      BOOTM_STATE_RAMDISK |
@@ -92,7 +96,7 @@ int do_booti(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 #ifdef CONFIG_SYS_LONGHELP
 static char booti_help_text[] =
 	"[addr [initrd[:size]] [fdt]]\n"
-	"    - boot arm64 Linux Image stored in memory\n"
+	"    - boot arm64/riscv Linux Image stored in memory\n"
 	"\tThe argument 'initrd' is optional and specifies the address\n"
 	"\tof an initrd in memory. The optional parameter ':size' allows\n"
 	"\tspecifying the size of a RAW initrd.\n"
@@ -107,5 +111,5 @@ static char booti_help_text[] =
 
 U_BOOT_CMD(
 	booti,	CONFIG_SYS_MAXARGS,	1,	do_booti,
-	"boot arm64 Linux Image image from memory", booti_help_text
+	"boot arm64/riscv Linux Image image from memory", booti_help_text
 );
-- 
2.21.0