u-boot.bin and u-boot.imx

[tomfang]

Hi,

Today i generated a u-boot.imx file to burn into SD card, it works ok,

my question is what is the difference between u-boot.bin and u-boot.imx?

i have known there is a 1K data has been added in u-boot.bin,

but i don't know what the data includes which informations.

part command is:

$[u-boot path]/tools/mkimage -T imximage

the parameter :"imximage" after 'T" represents for what?

hope some's help, thanks!

[tomfang]

could anyone explain details about the ROM code activities?

currently, i used the u-boot-2013-04 source code to generate

a u-boot.bin and u-boot.imx which work well, i just want to lean

more, for example, how can i to dig out where the u-boot well run on?

(it seems that the start address(TEXT_BASE) is 0x17800000)

does anyone provide any documents about those knowledges?

Thanks!

[AnsonHuang]

You can look into the HEX code of u-boot.imx, for the first 1K structure, the beginning is formatted as below, this header is for uboot-v2009.08, but I think uboot-2013-04 is same, although the code is different, but eventually they will both put a header in front of uboot.bin.

ROM will read first IVT header to identify which mode need to execute, DCD or PLUG, if DCD mode, then where to find the DRAM config data, and after DRAM configured, where to read the reset uboot image and where to put this image, in which DRAM address etc.

The TEXT_BASE is the address of uboot.bin location, I meant where to put this u-boot.bin. Normally it should be the DRAM address and should reserve some space for other utility, such as mem alloc and global data, gd = (gd_t*)(_armboot_start - CFG_MALLOC_LEN - sizeof(gd_t));

So I think the TEXT_BASE should be as least CFG_MALLOC_LEN + sizeof(gd_t) offset from the start of DRAM.

43 ivt_header:       .word 0x402000D1 /* Tag=0xD1, Len=0x0020, Ver=0x40 */

44 app_code_jump_v:  .word _start

45 reserv1:          .word 0x0

46 dcd_ptr:          .word dcd_hdr

47 boot_data_ptr:    .word boot_data

48 self_ptr:         .word ivt_header

49 #ifdef CONFIG_SECURE_BOOT

50 app_code_csf:     .word __hab_data

51 #else

52 app_code_csf:     .word 0x0

53 #endif

54 reserv2:          .word 0x0

55

56 boot_data:        .word TEXT_BASE

57 #ifdef CONFIG_SECURE_BOOT

58 image_len:        .word __hab_data_end - TEXT_BASE + CONFIG_FLASH_HEADER_OFFSET

59 #else

60 image_len:        .word _end_of_copy  - TEXT_BASE + CONFIG_FLASH_HEADER_OFFSET

61 #endif

62 plugin:           .word 0x0

63

64 #if defined CONFIG_MX6DL_DDR3

65 #if defined CONFIG_DDR_32BIT

66 dcd_hdr:          .word 0x40E001D2 /* Tag=0xD2, Len=59*8 + 4 + 4, Ver=0x40 */

67 write_dcd_cmd:    .word 0x04DC01CC /* Tag=0xCC, Len=59*8 + 4, Param=0x04 */

[tomfang]

Thanks Yongcai, I understand now

[AnsonHuang · Accepted solution]

Hi, tom

     The difference between u-boot.bin and u-boot.imx is the IVT header. That means after u-boot.bin is build, we will also add a IVT header and put it in front of u-boot.bin. This IVT header is for our boot ROM to identify the u-boot's location & function etc...

     The parameter "imximage" means telling mkimage tool to generate a imx uboot image, which means to put a header defined by image_type_params, then full in the imx content. So we will see after u-boot.imx generated, it is actually u-boot.bin with a imx IVT header which include header, DCD/plugin. For more detail, you can refer to:

tools/imximage.c.

[tomfang]

Hi Yongcai,

Thanks for your detailing description!

I got your mean.

Thanks

[AnsonHuang]

Welcome, can you set this question as answered if you think this is done, thanks in advanced!