| Stefano Babic | eae4988 | 2011-01-20 08:05:15 +0000 | [diff] [blame] | 1 | Overview |
| 2 | -------------- |
| 3 | |
| 4 | mx35pdk (known als as mx35_3stack) is a development board by Freescale. |
| 5 | It consists of three pluggable board: |
| 6 | - CPU module, with CPU, RAM, flash |
| 7 | - Personality board, with most interfaces (USB, Network,..) |
| 8 | - Debug board with JTAG header. |
| 9 | |
| 10 | The board is usually delivered with redboot. This howto explains how to boot |
| 11 | a linux kernel and how to replace the original bootloader with U-Boot. |
| 12 | |
| 13 | The board is delivered with Redboot on the NAND flash. It is possible to |
| 14 | switch the boot device with the switches SW1-SW2 on the Personality board, |
| 15 | and with SW5-SW10 on the Debug board. |
| 16 | |
| 17 | Delivered Redboot script to start the kernel |
| 18 | --------------------------------------------------- |
| 19 | |
| 20 | In redboot the following script is stored: |
| 21 | |
| 22 | fis load kernel |
| 23 | exec -c "noinitrd console=ttymxc0,115200 root=/dev/mtdblock8 rw rootfstype=jffs2 ip=dhcp fec_mac=00:04:9F:00:E7:76" |
| 24 | |
| 25 | Kernel is taken from flash. The image is in zImage format. |
| 26 | |
| 27 | Booting from NET, rootfs on NFS: |
| 28 | ----------------------------------- |
| 29 | |
| 30 | To change the script in redboot: |
| 31 | |
| 32 | load -r -b 0x100000 <path_to_zImage> |
| 33 | exec -c "noinitrd console=ttymxc0,115200 root=/dev/nfsroot rootfstype=nfsroot nfsroot=192.168.1.1:/opt/eldk-4.2-arm/armVFP rw ip=dhcp" |
| 34 | |
| 35 | If the ip address is not set, you can set it with : |
| 36 | |
| 37 | ip_address -l <board_ip/netmask> -h <server_ip> |
| 38 | |
| 39 | Linux partitions: |
| 40 | --------------------------- |
| 41 | |
| 42 | As default, the board is shipped with these partition tables for NAND |
| 43 | and for NOR: |
| 44 | |
| 45 | Creating 5 MTD partitions on "NAND 2GiB 3,3V 8-bit": |
| 46 | 0x00000000-0x00100000 : "nand.bootloader" |
| 47 | 0x00100000-0x00600000 : "nand.kernel" |
| 48 | 0x00600000-0x06600000 : "nand.rootfs" |
| 49 | 0x06600000-0x06e00000 : "nand.configure" |
| 50 | 0x06e00000-0x80000000 : "nand.userfs" |
| 51 | |
| 52 | Creating 6 MTD partitions on "mxc_nor_flash.0": |
| 53 | 0x00000000-0x00080000 : "Bootloader" |
| 54 | 0x00080000-0x00480000 : "nor.Kernel" |
| 55 | 0x00480000-0x02280000 : "nor.userfs" |
| 56 | 0x02280000-0x03e80000 : "nor.rootfs" |
| 57 | 0x01fe0000-0x01fe3000 : "FIS directory" |
| 58 | 0x01fff000-0x04000000 : "Redboot config" |
| 59 | |
| 60 | NAND partitions can be recognized enabling in kernel CONFIG_MTD_REDBOOT_PARTS. |
| 61 | For this board, CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK should be set to 2. |
| 62 | |
| 63 | However, the setup in redboot is not correct and does not use the whole flash. |
| 64 | |
| 65 | Better solution is to use the kernel parameter mtdparts. |
| 66 | Here the resulting script to be defined in RedBoot with fconfig: |
| 67 | |
| 68 | load -r -b 0x100000 sbabic/mx35pdk/zImage.2.6.37 |
| 69 | exec -c "noinitrd console=ttymxc0,115200 root=/dev/nfsroot rootfstype=nfsroot nfsroot=192.168.1.1:/opt/eldk-4.2-arm/arm rw ip=dhcp mtdparts=mxc_nand:1m(boot),5m(linux),96m(root),8m(cfg),1938m(user);physmap-flash.0:512k(b),4m(k),30m(u),28m(r)" |
| 70 | |
| 71 | Flashing U-Boot |
| 72 | -------------------------------- |
| 73 | |
| Fabio Estevam | 1d9b033 | 2012-09-14 12:14:54 +0000 | [diff] [blame] | 74 | U-boot should be stored on the NOR flash. |
| 75 | |
| Stefano Babic | eae4988 | 2011-01-20 08:05:15 +0000 | [diff] [blame] | 76 | The boot storage can be select using the switches on the personality board |
| 77 | (SW1-SW2) and on the DEBUG board (SW4-SW10). |
| 78 | |
| Stefano Babic | eae4988 | 2011-01-20 08:05:15 +0000 | [diff] [blame] | 79 | If something goes wrong flashing the bootloader, it is always possible to |
| 80 | recover the board booting from the other device. |
| 81 | |
| Stefano Babic | eae4988 | 2011-01-20 08:05:15 +0000 | [diff] [blame] | 82 | Saving U-Boot in the NOR flash |
| 83 | --------------------------------- |
| 84 | |
| Stefano Babic | eae4988 | 2011-01-20 08:05:15 +0000 | [diff] [blame] | 85 | Check the partition for boot in the NOR flash. Setting the mtdparts as reported, |
| 86 | the boot partition should be /dev/mtd0. |
| 87 | |
| 88 | Creating 6 MTD partitions on "mxc_nor_flash.0": |
| 89 | 0x00000000-0x00080000 : "Bootloader" |
| 90 | 0x00080000-0x00480000 : "nor.Kernel" |
| 91 | 0x00480000-0x02280000 : "nor.userfs" |
| 92 | 0x02280000-0x03e80000 : "nor.rootfs" |
| 93 | 0x01fe0000-0x01fe3000 : "FIS directory" |
| 94 | 0x01fff000-0x04000000 : "Redboot config" |
| 95 | |
| 96 | To erase the whole partition: |
| 97 | $ flash_eraseall /dev/mtd0 |
| 98 | |
| 99 | Writing u-boot: |
| 100 | dd if=u-boot.bin of=/dev/mtd0 |
| 101 | |
| 102 | To boot from NOR, you have to select the switches as follows: |
| 103 | |
| 104 | Personality board |
| 105 | SW2 all off |
| 106 | SW1 all off |
| 107 | |
| 108 | Debug Board: |
| 109 | SW5 0 |
| 110 | SW6 0 |
| 111 | SW7 0 |
| 112 | SW8 1 |
| 113 | SW9 1 |
| 114 | SW10 0 |