rockchip: Add the rkimage format to mkimage

Rockchip SoCs require certain formats for code that they execute, The
simplest format is a 4-byte header at the start of a binary file. Add
support for this so that we can create images that the boot ROM understands.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/common/image.c b/common/image.c
index 678588d..cf2806f 100644
--- a/common/image.c
+++ b/common/image.c
@@ -155,6 +155,7 @@
 	{	IH_TYPE_ATMELIMAGE, "atmelimage", "ATMEL ROM-Boot Image",},
 	{	IH_TYPE_X86_SETUP,  "x86_setup",  "x86 setup.bin",    },
 	{	IH_TYPE_LPC32XXIMAGE, "lpc32xximage",  "LPC32XX Boot Image", },
+	{	IH_TYPE_RKIMAGE,    "rkimage",    "Rockchip Boot Image" },
 	{	-1,		    "",		  "",			},
 };
 
diff --git a/include/image.h b/include/image.h
index 63c3d37..2daa74a 100644
--- a/include/image.h
+++ b/include/image.h
@@ -245,8 +245,9 @@
 #define IH_TYPE_X86_SETUP	20	/* x86 setup.bin Image		*/
 #define IH_TYPE_LPC32XXIMAGE	21	/* x86 setup.bin Image		*/
 #define IH_TYPE_LOADABLE	22	/* A list of typeless images	*/
+#define IH_TYPE_RKIMAGE		23	/* Rockchip Boot Image		*/
 
-#define IH_TYPE_COUNT		23	/* Number of image types */
+#define IH_TYPE_COUNT		24	/* Number of image types */
 
 /*
  * Compression Types
diff --git a/tools/Makefile b/tools/Makefile
index f673258..267f55c 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -64,6 +64,8 @@
 					rsa-sign.o rsa-verify.o rsa-checksum.o \
 					rsa-mod-exp.o)
 
+ROCKCHIP_OBS = lib/rc4.o rkcommon.o rkimage.o
+
 # common objs for dumpimage and mkimage
 dumpimage-mkimage-objs := aisimage.o \
 			atmelimage.o \
@@ -90,6 +92,7 @@
 			os_support.o \
 			pblimage.o \
 			pbl_crc32.o \
+			$(ROCKCHIP_OBS) \
 			socfpgaimage.o \
 			lib/sha1.o \
 			lib/sha256.o \
diff --git a/tools/rkcommon.c b/tools/rkcommon.c
new file mode 100644
index 0000000..4389622
--- /dev/null
+++ b/tools/rkcommon.c
@@ -0,0 +1,72 @@
+/*
+ * (C) Copyright 2015 Google,  Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * Helper functions for Rockchip images
+ */
+
+#include "imagetool.h"
+#include <image.h>
+#include <rc4.h>
+#include "mkimage.h"
+#include "rkcommon.h"
+
+enum {
+	RK_SIGNATURE		= 0x0ff0aa55,
+};
+
+/**
+ * struct header0_info - header block for boot ROM
+ *
+ * This is stored at SD card block 64 (where each block is 512 bytes, or at
+ * the start of SPI flash. It is encoded with RC4.
+ *
+ * @signature:		Signature (must be RKSD_SIGNATURE)
+ * @disable_rc4:	0 to use rc4 for boot image,  1 to use plain binary
+ * @code1_offset:	Offset in blocks of the SPL code from this header
+ *			block. E.g. 4 means 2KB after the start of this header.
+ * Other fields are not used by U-Boot
+ */
+struct header0_info {
+	uint32_t signature;
+	uint8_t reserved[4];
+	uint32_t disable_rc4;
+	uint16_t code1_offset;
+	uint16_t code2_offset;
+	uint8_t reserved1[490];
+	uint16_t usflashdatasize;
+	uint16_t ucflashbootsize;
+	uint8_t reserved2[2];
+};
+
+static unsigned char rc4_key[16] = {
+	124, 78, 3, 4, 85, 5, 9, 7,
+	45, 44, 123, 56, 23, 13, 23, 17
+};
+
+int rkcommon_set_header(void *buf, uint file_size)
+{
+	struct header0_info *hdr;
+
+	if (file_size > RK_MAX_CODE1_SIZE)
+		return -ENOSPC;
+
+	memset(buf,  '\0', RK_CODE1_OFFSET * RK_BLK_SIZE);
+	hdr = (struct header0_info *)buf;
+	hdr->signature = RK_SIGNATURE;
+	hdr->disable_rc4 = 1;
+	hdr->code1_offset = RK_CODE1_OFFSET;
+	hdr->code2_offset = 8;
+
+	hdr->usflashdatasize = (file_size + RK_BLK_SIZE - 1) / RK_BLK_SIZE;
+	hdr->usflashdatasize = (hdr->usflashdatasize + 3) & ~3;
+	hdr->ucflashbootsize = hdr->usflashdatasize;
+
+	debug("size=%x, %x\n", params->file_size, hdr->usflashdatasize);
+
+	rc4_encode(buf, RK_BLK_SIZE, rc4_key);
+
+	return 0;
+}
diff --git a/tools/rkcommon.h b/tools/rkcommon.h
new file mode 100644
index 0000000..57fd726
--- /dev/null
+++ b/tools/rkcommon.h
@@ -0,0 +1,28 @@
+/*
+ * (C) Copyright 2015 Google,  Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _RKCOMMON_H
+#define _RKCOMMON_H
+
+enum {
+	RK_BLK_SIZE		= 512,
+	RK_CODE1_OFFSET		= 4,
+	RK_MAX_CODE1_SIZE	= 32 << 10,
+};
+
+/**
+ * rkcommon_set_header() - set up the header for a Rockchip boot image
+ *
+ * This sets up a 2KB header which can be interpreted by the Rockchip boot ROM.
+ *
+ * @buf:	Pointer to header place (must be at least 2KB in size)
+ * @file_size:	Size of the file we want the boot ROM to load, in bytes
+ * @return 0 if OK, -ENOSPC if too large
+ */
+int rkcommon_set_header(void *buf, uint file_size);
+
+#endif
diff --git a/tools/rkimage.c b/tools/rkimage.c
new file mode 100644
index 0000000..7b292f4
--- /dev/null
+++ b/tools/rkimage.c
@@ -0,0 +1,65 @@
+/*
+ * (C) Copyright 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * See README.rockchip for details of the rkimage format
+ */
+
+#include "imagetool.h"
+#include <image.h>
+
+static uint32_t header;
+
+static int rkimage_check_params(struct image_tool_params *params)
+{
+	return 0;
+}
+
+static int rkimage_verify_header(unsigned char *buf, int size,
+				 struct image_tool_params *params)
+{
+	return 0;
+}
+
+static void rkimage_print_header(const void *buf)
+{
+}
+
+static void rkimage_set_header(void *buf, struct stat *sbuf, int ifd,
+			       struct image_tool_params *params)
+{
+	memcpy(buf, "RK32", 4);
+}
+
+static int rkimage_extract_subimage(void *buf, struct image_tool_params *params)
+{
+	return 0;
+}
+
+static int rkimage_check_image_type(uint8_t type)
+{
+	if (type == IH_TYPE_RKIMAGE)
+		return EXIT_SUCCESS;
+	else
+		return EXIT_FAILURE;
+}
+
+/*
+ * rk_image parameters
+ */
+U_BOOT_IMAGE_TYPE(
+	rkimage,
+	"Rockchip Boot Image support",
+	4,
+	&header,
+	rkimage_check_params,
+	rkimage_verify_header,
+	rkimage_print_header,
+	rkimage_set_header,
+	rkimage_extract_subimage,
+	rkimage_check_image_type,
+	NULL,
+	NULL
+);