1 --------------------------------------------- 2 Imximage Boot Image generation using mkimage 3 --------------------------------------------- 4 5 This document describes how to set up a U-Boot image that can be booted 6 by Freescale MX25, MX35, MX51, MX53 and MX6 processors via internal boot 7 mode. 8 9 These processors can boot directly from NAND, SPI flash and SD card flash 10 using its internal boot ROM support. MX6 processors additionally support 11 boot from NOR flash and SATA disks. All processors can boot from an internal 12 UART, if booting from device media fails. 13 Booting from NOR flash does not require to use this image type. 14 15 For more details refer Chapter 2 - System Boot and section 2.14 16 (flash header description) of the processor's manual. 17 18 Command syntax: 19 -------------- 20 ./tools/mkimage -l <mx u-boot_file> 21 to list the imx image file details 22 23 ./tools/mkimage -T imximage \ 24 -n <board specific configuration file> \ 25 -e <execution address> -d <u-boot binary> <output image file> 26 27 For example, for the mx51evk board: 28 ./tools/mkimage -n ./board/freescale/mx51evk/imximage.cfg \ 29 -T imximage -e 0x97800000 \ 30 -d u-boot.bin u-boot.imx 31 32 You can generate directly the image when you compile u-boot with: 33 34 $ make u-boot.imx 35 36 The output image can be flashed on the board SPI flash or on a SD card. 37 In both cases, you have to copy the image at the offset required for the 38 chosen media devices (0x400 for both SPI flash or SD card). 39 40 Please check Freescale documentation for further details. 41 42 Board specific configuration file specifications: 43 ------------------------------------------------- 44 1. This file must present in the $(BOARDDIR) and the name should be 45 imximage.cfg (since this is used in Makefile). 46 2. This file can have empty lines and lines starting with "#" as first 47 character to put comments. 48 3. This file can have configuration command lines as mentioned below, 49 any other information in this file is treated as invalid. 50 51 Configuration command line syntax: 52 --------------------------------- 53 1. Each command line is must have two strings, first one command or address 54 and second one data string 55 2. Following are the valid command strings and associated data strings:- 56 Command string data string 57 -------------- ----------- 58 IMXIMAGE_VERSION 1/2 59 1 is for mx25/mx35/mx51 compatible, 60 2 is for mx53/mx6 compatible, 61 others is invalid and error is generated. 62 This command need appear the fist before 63 other valid commands in configuration file. 64 65 BOOT_OFFSET value 66 67 This command is parallel to BOOT_FROM and 68 is preferred over BOOT_FROM. 69 70 value: Offset of the image header, this 71 value shall be set to one of the 72 values found in the file: 73 arch/arm/include/asm/\ 74 mach-imx/imximage.cfg 75 Example: 76 BOOT_OFFSET FLASH_OFFSET_STANDARD 77 78 BOOT_FROM nand/spi/sd/onenand/nor/sata 79 80 This command is parallel to BOOT_OFFSET and 81 is to be deprecated in favor of BOOT_OFFSET. 82 83 Example: 84 BOOT_FROM spi 85 86 CSF value 87 88 Total size of CSF (Command Sequence File) 89 used for Secure Boot/ High Assurance Boot 90 (HAB). 91 92 Using this command will populate the IVT 93 (Initial Vector Table) CSF pointer and adjust 94 the length fields only. The CSF itself needs 95 to be generated with Freescale tools and 96 'manually' appended to the u-boot.imx file. 97 98 The CSF is then simply concatenated 99 to the u-boot image, making a signed bootloader, 100 that the processor can verify 101 if the fuses for the keys are burned. 102 103 Further infos how to configure the SOC to verify 104 the bootloader can be found in the "High 105 Assurance Boot Version Application Programming 106 Interface Reference Manual" as part of the 107 Freescale Code Signing Tool, available on the 108 manufacturer's website. 109 110 Example: 111 CSF 0x2000 112 113 DATA type address value 114 115 type: word=4, halfword=2, byte=1 116 address: physycal register address 117 value: value to be set in register 118 All values are in in hexadecimal. 119 Example (write to IOMUXC): 120 DATA 4 0x73FA88a0 0x200 121 122 The processor support up to 60 register programming commands for IMXIMAGE_VERSION 1 123 and 220 register programming commands for IMXIMAGE_VERSION 2. 124 An error is generated if more commands are found in the configuration file. 125 126 3. All commands are optional to program. 127 128 Setup a SD Card for booting 129 -------------------------------- 130 131 The following example prepare a SD card with u-boot and a FAT partition 132 to be used to stored the kernel to be booted. 133 I will set the SD in the most compatible mode, setting it with 134 255 heads and 63 sectors, as suggested from several documentation and 135 howto on line (I took as reference the preparation of a SD Card for the 136 Beagleboard, running u-boot as bootloader). 137 138 You should start clearing the partitions table on the SD card. Because 139 the u-boot image must be stored at the offset 0x400, it must be assured 140 that there is no partition at that address. A new SD card is already 141 formatted with FAT filesystem and the partition starts from the first 142 cylinder, so we need to change it. 143 144 You can do all steps with fdisk. If the device for the SD card is 145 /dev/mmcblk0, the following commands make the job: 146 147 1. Start the fdisk utility (as superuser) 148 fdisk /dev/mmcblk0 149 150 2. Clear the actual partition 151 152 Command (m for help): o 153 154 3. Print card info: 155 156 Command (m for help): p 157 Disk /dev/mmcblk0: 1981 MB, 1981284352 bytes 158 159 In my case, I have a 2 GB card. I need the size to set later the correct value 160 for the cylinders. 161 162 4. Go to expert mode: 163 164 Command (m for help): x 165 166 5. Set card geometry 167 168 Expert command (m for help): h 169 Number of heads (1-256, default 4): 255 170 171 Expert command (m for help): s 172 Number of sectors (1-63, default 16): 63 173 Warning: setting sector offset for DOS compatiblity 174 175 We have set 255 heads, 63 sector. We have to set the cylinder. 176 The value to be set can be calculated with: 177 178 cilynder = <total size> / <heads> / <sectors> / <blocksize> 179 180 in this example, 181 1981284352 / 255 / 63 / 512 = 239.x = 239 182 183 184 Expert command (m for help): c 185 Number of cylinders (1-1048576, default 60032): 239 186 187 6. Leave the expert mode 188 Expert command (m for help): r 189 190 7. Set up a partition 191 192 Now set a partition table to store the kernel or whatever you want. Of course, 193 you can set additional partitions to store rootfs, data, etc. 194 In my example I want to set a single partition. I must take care 195 to not overwrite the space where I will put u-boot. 196 197 Command (m for help): n 198 Command action 199 e extended 200 p primary partition (1-4) 201 p 202 Partition number (1-4): 1 203 First cylinder (1-239, default 1): 3 204 Last cylinder, +cylinders or +size{K,M,G} (3-239, default 239): +100M 205 206 Command (m for help): p 207 208 Disk /dev/mmcblk0: 1967 MB, 1967128576 bytes 209 255 heads, 63 sectors/track, 239 cylinders 210 Units = cylinders of 16065 * 512 = 8225280 bytes 211 Disk identifier: 0xb712a870 212 213 Device Boot Start End Blocks Id System 214 /dev/mmcblk0p1 3 16 112455 83 Linux 215 216 I have set 100MB, leaving the first 2 sectors free. I will copy u-boot 217 there. 218 219 8. Write the partition table and exit. 220 221 Command (m for help): w 222 The partition table has been altered! 223 224 Calling ioctl() to re-read partition table. 225 226 9. Copy u-boot.imx on the SD card 227 228 I use dd: 229 230 dd if=u-boot.imx of=/dev/mmcblk0 bs=512 seek=2 231 232 This command copies the u-boot image at the address 0x400, as required 233 by the processor. 234 235 Now remove your card from the PC and go to the target. If evrything went right, 236 the u-boot prompt should come after power on. 237 238 ------------------------------------------------ 239 Author: Stefano babic <sbabic (a] denx.de> 240
