i.MX ProcessorsのトピックBoot from fuses for eMMC

Boot from fuses for eMMC

jsmith883 — Mon, 27 Aug 2018 21:14:40 GMT

Hello,

I am trying to boot from fuses on an eMMC, but something is not working right. The eMMC is is on SD4, 8-bit bus width. Before blowing the fuses, I was booting from GPIOs on the same eMMC. The SBMR register was reading 0x5870. I then set the fuses by the following command:

echo 0x5870 > /sys/fsl_otp/HW_OCOTP_CFG5

echo 0x10 > /sys/fsl_otp/HW_OCOTP_CFG6

Once I reset the board, the board no longer boots. When I look at the registers now the SBMR is reading 0x0, and the OCOTP_CFG5 is reading 0x5870. OCOTP_CFG6 is reading 0x10. SBMR2 is reading 0x71.

However, if I plug in the OTG USB, the manufacturing tool will boot the board immediately, as if it's configured for serial download. Any idea why this is not working correctly?

Re: Boot from fuses for eMMC

igorpadykov — Mon, 27 Aug 2018 23:45:04 GMT

Hi jsmith883

what processor used in the case, in particular for example for i.MX6DQ behaviour

is described in sect.8.2.3 Boot From Fuses mode (BOOT_MODE[1:0] = 00b)

i.MX6DQ Reference Manual :

If set to Boot From Fuses, the boot flow is controlled by the BT_FUSE_SEL eFUSE
value. If BT_FUSE_SEL = 0, indicating that the boot device (for example, flash, SD/
MMC) was not programmed yet, the boot flow jumps directly to the Serial Downloader.

https://www.nxp.com/docs/en/reference-manual/IMX6DQRM.pdf

Best regards
igor
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Re: Boot from fuses for eMMC

jsmith883 — Tue, 28 Aug 2018 13:55:52 GMT

@igorpadykov,

I have an i.MX6 DUAL/QUAD processor. I'm reading BT_FUSE_SEL = 1, so it should be booting from fuses. It was able to boot from the eMMC using the GPIO pins, so I know that it's already flashed and can boot from this device. Then when I blew the fuses so that it would boot from fuses, it does not boot. Is there something else I need to do to the eMMC or some other fuse/register that I need to set?

Re: Boot from fuses for eMMC

jsmith883 — Fri, 31 Aug 2018 18:49:59 GMT

igorpadykov‌,

Any thoughts? Is there something else I need to do to the eMMC or some other fuse/register that I need to set for it to properly boot?

Re: Boot from fuses for eMMC

igorpadykov — Fri, 31 Aug 2018 23:34:30 GMT

Hi jsmith883

could you read back fuses and verify that they are programmed correctly.

Q&A: How to program i.MX6 eFUSE?

Fuse API - Boundary Devices

Best regards
igor

Re: Boot from fuses for eMMC

jsmith883 — Tue, 04 Sep 2018 15:00:44 GMT

igorpadykov‌,

The fuses are reading back correctly. Here is what I read via JTAG: OCOTP_CFG5 is reading 0x5870. OCOTP_CFG6 is reading 0x10. Before I always had to set the boot_config and boot_bus_config for the eMMC to boot, but I can't do this with the manufacturing tool.

echo 8 > /sys/bus/mmc/devices/mmc1\:0001/boot_config
echo 2 > /sys/bus/mmc/devices/mmc1\:0001/boot_bus_config

Is there a way to set this with the manufacturing tool?

Re: Boot from fuses for eMMC

joshbarnheiser — Tue, 04 Sep 2018 16:42:53 GMT

jsmith883,

You may be able to do the same as the echo commands using the mmc command in the initramfs.

For your configuration try:

mmc bootpart enable 1 1 /dev/mmcblk1

mmc bootbus set single_hs x1 x8 /dev/mmcblk1

Embedded Linux Boot Scenarios

Cheers,

Josh

Re: Boot from fuses for eMMC

igorpadykov — Wed, 05 Sep 2018 01:03:23 GMT

Hi jsmith883

I believe it may be supported by mfg tool, please check ucl2.xml file

in mfg tool package on link below

i.MX Software|NXP

Best regards
igor