nmhw: redundant u-boot start from SPL

- copy redundant boot from nrsw implementation
- rewritten to fix issues with load size and load address
- support for NetModule packed or regulator bootloaders
  in main and alternate location
- support is currently experimental.
  write 0x12345678 to 0x90000004 to try out

arch/arm/include/asm/arch-am33xx/spl.h

@@ -47,6 +47,7 @@
 #define BOOT_DEVICE_UART	0x41
 #define BOOT_DEVICE_USBETH	0x44
 #define BOOT_DEVICE_CPGMAC	0x46
+#define BOOT_DEVICE_JTAG        0x58
 
 #define MMC_BOOT_DEVICES_START	BOOT_DEVICE_MMC1
 #define MMC_BOOT_DEVICES_END	BOOT_DEVICE_MMC2

common/spl/spl_mmc.c

@@ -18,6 +18,113 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+
+static int image_nm_magic(const struct nm_header *header)
+{
+	u32 start_tag = __be32_to_cpu(header->nm_start_tag);
+	u32 length = __be32_to_cpu(header->nm_length);
+
+	printf("checking nm header. start tag = 0x%08x, length = %d\n", start_tag, length);
+
+	if ((start_tag == 0x424c5354) &&
+	    (length > 128*1024) && (length < 2500*1024))
+	{
+		printf("valid netmodule bootloader found\n");
+		return 0;
+	}
+	else {
+		return -1;
+	}
+}
+
+static int mmc_load_netmodule(struct mmc *mmc, ulong sector,
+			      const struct nm_header *header)
+{
+	const struct image_header *im_header;
+	const __be32* end_tag_position;
+	u32 image_size_sectors;
+	unsigned long count; 
+	u32 end_tag;
+	int ret;
+
+	im_header = &(header->header);
+	printf("nm header %p\n", header);
+	printf("im header %p\n", im_header);
+
+	/* decode header and fill out spl_image structure */
+	ret = spl_parse_image_header(im_header);
+	printf("mmc_load_netmodule checking header 1: %d\n", ret);
+	if (ret)
+		return ret;
+
+	printf("spl header: load addr 0x%08x\n", spl_image.load_addr);
+	printf("spl header: size %d\n", spl_image.size);
+
+	/* convert size to sectors - round up,
+	 * add 256 bytes for NetModule header, 4 bytes for NetModule trailer 
+	 */
+	image_size_sectors = (spl_image.size + 256 + 4 + mmc->read_bl_len - 1) /
+			     mmc->read_bl_len;
+	printf("mmc_load_netmodule 3: %u\n", image_size_sectors);
+
+	/* Read the header too to avoid extra memcpy,
+	 * compensate the load address for the NetModule header 
+	 */
+	count = blk_dread(mmc_get_blk_desc(mmc), sector, image_size_sectors,
+			  (void *)(ulong)spl_image.load_addr - 256);
+	debug("read %x sectors to %x\n", image_size_sectors,
+	      spl_image.load_addr);
+
+	if (count != image_size_sectors)
+		return -EIO;
+
+	/* Check NetModule end tag to be sure image is completely written */
+	end_tag_position =  (const __be32*)(spl_image.load_addr + spl_image.size);
+	printf("end tag address %p\n", end_tag_position);
+	end_tag = __be32_to_cpu(*end_tag_position);
+	printf("end tag 0x%08x\n", end_tag);
+	if (end_tag != 0x424c454e)
+		return -EFAULT;
+
+	return 0;
+}
+
+static int mmc_load_image_raw_sector_netmodule(struct mmc *mmc, unsigned long sector)
+{
+	unsigned long count;
+	struct nm_header *header;
+	int ret = 0;
+
+	printf("\ntrying to load NM packaged u-boot from sector %lu\n", sector);
+
+	header = (struct nm_header *)(CONFIG_SYS_TEXT_BASE -
+					 sizeof(struct nm_header));
+
+	/* read image header to find the image size & load address */
+	count = blk_dread(mmc_get_blk_desc(mmc), sector, 1, header);
+	debug("hdr read sector %lx, count=%lu\n", sector, count);
+	if (count == 0) {
+		ret = -EIO;
+		goto end;
+	}
+
+	printf("header loaded to %p\n", header);
+
+	if (image_nm_magic(header) == 0) {
+		ret = mmc_load_netmodule(mmc, sector, header);
+		printf("NM image loaded, ret =  %d\n", ret);
+	} else {
+		ret = -EFAULT;
+	}
+
+end:
+	if (ret) {
+		return -1;
+	}
+
+	return 0;
+}
+
 static int mmc_load_legacy(struct mmc *mmc, ulong sector,
 			   struct image_header *header)
 {
@@ -321,11 +428,41 @@ int spl_mmc_load_image(u32 boot_device)
 			CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION);
 		if (!err)
 			return err;
+
 #if defined(CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR)
+		if (*(u32*)0x90000004 == 0x12345678) {
+			printf("Testing redundancy boot\n");
+
+			/* Try to load NetModule packed bootloader from 
+			 * main location */
+			err = mmc_load_image_raw_sector_netmodule(mmc,
+				CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR);
+				if (!err)
+					return err;	/* found -> ok */
+
+			/* Try to load NetModule packed bootloader from 
+			 * alternate location */
+			err = mmc_load_image_raw_sector_netmodule(mmc,
+				CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR_ALTERNATE);
+				if (!err)
+					return err;	/* found -> ok */
+
+			/* Try to load regular bootloader from 
+			 * alternate location */
+			err = mmc_load_image_raw_sector(mmc,
+				CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR_ALTERNATE);
+			if (!err) {
+				puts("starting alternate bootloader\n");
+				return err;	/* found -> ok */
+			}
+		}
+
+		/* Try to load bootloader from main location */
 		err = mmc_load_image_raw_sector(mmc,
 			CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR);
 		if (!err)
-			return err;
+			return err;	/* found -> ok */
+
 #endif
 		/* If RAW mode fails, try FS mode. */
 	case MMCSD_MODE_FS:

include/configs/ti_armv7_common.h

@@ -220,6 +220,7 @@
 
 /* RAW SD card / eMMC locations. */
 #define CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR	0x300 /* address 0x60000 */
+#define CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR_ALTERNATE 0x1b00 /* address 0x360000  */
 #define CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS	0x200 /* 256 KB */
 
 /* FAT sd card locations. */

include/image.h

@@ -286,6 +286,14 @@ typedef struct image_header {
 	uint8_t		ih_name[IH_NMLEN];	/* Image Name		*/
 } image_header_t;
 
+typedef struct nm_header {
+	__be32		nm_start_tag;	/* BLST (0x424c5354) */
+	__be32		nm_version;	/* U-boot version number */
+	__be32		nm_length;	/* U-boot image length */
+	uint8_t		reserved[244];	/* Reserved */
+	struct image_header header;
+} nm_header_t;
+
 typedef struct image_info {
 	ulong		start, end;		/* start/end of blob */
 	ulong		image_start, image_len; /* start of image within blob, len of image */