emmc 中boot partition的配置

small_snap

EMMC的boot partition有两个，mmcblk0boot0和mmcblk0boot1，可以在linux下通过mmc_utils动态配置，但看到网上有些直接写boot_config文件也可以实现boot partition的切换，比如在网上看到一个人这样做：

==========================================================================================
For i.MX6 based modules, migrating to booting off the primary hardware boot area partition incl. flashing a new U-Boot there:
root@colibri-imx6:~# echo 0 > /sys/block/mmcblk0boot0/force_ro
root@colibri-imx6:~# dd if=u-boot.imx of=/dev/mmcblk0boot0 bs=512 seek=2
[  222.394014]  mmcblk0boot0: unknown partition table
598+0 records in
598+0 records out
root@colibri-imx6:~# echo 1 > /sys/block/mmcblk0boot0/force_ro
root@colibri-imx6:~# echo 10 > /sys/devices/soc0/soc.0/2100000.aips-bus/2198000.usdhc/mmc_host/mmc0/mmc0\:0001/boot_bus_config
root@colibri-imx6:~# echo 8 > /sys/devices/soc0/soc.0/2100000.aips-bus/2198000.usdhc/mmc_host/mmc0/mmc0\:0001/boot_config
===========================================================================================

于是也想效仿，直接写boot_config文件，但我这边死活都找不到boot_config这个文件，不知道是不是需要打开config里的某些配置？望大侠们指教！

small_snap

比如这里还有一个：
==============================================================================
$ cd /sys/devices/platform/sdhci-esdhc-imx.2/mmc_host/mmc0/mmc0:0001
$ cat boot_info
boot_info:0x07;
  ALT_BOOT_MODE:1 - Supports alternate boot method
  DDR_BOOT_MODE:1 - Supports alternate dual data rate during boot
  HS_BOOTMODE:1 - Supports high speed timing during boot
boot_size:536870912KB
boot_partition:0x01;
  BOOT_ACK:0 - No boot acknowledge sent
  BOOT_PARTITION-ENABLE: 0 - Device not boot enabled
  PARTITION_ACCESS:1 - R/W boot partition 1
boot_bus:0x00
  BOOT_MODE:0 - Use single data rate + backward compatible timings in boot operation
$ echo 8 > boot_config
$ cat boot_info
boot_info:0x07;
  ALT_BOOT_MODE:1 - Supports alternate boot method
  DDR_BOOT_MODE:1 - Supports alternate dual data rate during boot
  HS_BOOTMODE:1 - Supports high speed timing during boot
boot_size:536870912KB
boot_partition:0x48;
  BOOT_ACK:1 - Boot acknowledge sent during boot operation
  BOOT_PARTITION-ENABLE: 1 - Boot partition 1 enabled
  PARTITION_ACCESS:0 - No access to boot partition
boot_bus:0x00
  BOOT_MODE:0 - Use single data rate + backward compatible timings in boot operation
======================================================================================

这里的boot_config究竟是哪里来的啊？有大侠知道吗？

small_snap

没有大侠知道吗。。。只能自己捣鼓。。。