eMMC Normal boot not work with x4,x8 DDR setting.

[takayuki_ishii]

Hello community,

I tested eMMC(rev 5.01) boot with i.mx6q sabre-sd USDHC2 I/F.

In fast boot mode (BOOT_CFG1[4] = 1), it can boot from boot partition both x8 and x4 DDR mode.

In normal boot mode (BOOT_CFG1[4] = 0) with x1,x4,x8 SDR mode, it can boot correctly.

But normal boot mode (BOOT_CFG1[4] = 0) with x4,x8 SDR mode, it can not boot both user partition and

boot partition of eMMC.

Base setting of USDHC boot eFUSE descriptions as following.

BOOT_CFG1[7:6] : 01 - boot from USDHC
BOOT_CFG1[5] : 1 - eMMC
BOOT_CFG1[4] : 0 - Normal boot
BOOT_CFG1[3:2] : 00 - High speed mode
BOOT_CFG1[1] : 0 - eMMC reset disable
BOOT_CFG1[0] : 0 - Throught the SD pad
BOOT_CFG2[7:5] : 101 - 4bit DDR
BOOT_CFG2[4:3] : 01 - USDHC-2
BOOT_CFG2[2] : 0 - Boot ROM default
BOOT_CFG2[1] : 0 - Boot acknowledge enable
BOOT_CFG2[0] : 0 - Use default values
MMC_DLL_DLY[6:0] : 0000000

Of case, I try to change BOOT_BUS_CONDITIONS [177] and

PARTITION_CONFIG (before BOOT_CONFIG) [179] in eMMC.

To boot eMMC with x4,x8 DDR in normal boot, need some more setting?

To see the eMMC bus signal log on ROM boot function,

I.MX6 output MMC_CMD and parameter based on the device boot flow in the IMX6DQRM Figure 8-11 and 8-16.

Switch command (CMD6) set PARTITION_CONFIG(0x01B34900), Hi-speed(0x03B9_0100) and BUS_WIDTH(0x03B70500) and eMMC respond with no error.

After send READ_MULTIPLE_BLOCK(CMD18) and read 512byte from sector 0,

i.MX6 stop MMC_CLK and no response any more.

Best regards,

Ishii.

[petter-osterlund]

I am on i.mx8mm and have similar problem.

We have used Micron eMMC in 8-bit DDR BOOT_CFG for a long time without problem. We now replace eMMC with corresponding Kioxia eMMC and ROM do not boot. Memory works perfect in U-boot and Linux when we bootstrap via serial download.

No plausible ideas what was problem from Kioxia/NXP as it should work. Then by almost an accident we changed to SDR mode and then it started working.

Did you ever get any insight in your problems Ishii?

[takayuki_ishii]

Hello Sun,

Thank you for your reply and sorry my less information.

I already shorted R712.

So both SD2(eMMC with SD-card socket adapter) and SDD4(on board eMMC) work

with DDR boot setting with EXT_CSD on eMMC device.

  BOOT_BUS_CONDITIONS [177].BOOT_MODE=0x02

Do I need some more setting to use DDR finction?

Best regards.

Ishii.

[weidong_sun]

Hello Takayuki,

    I compared your configurations for booting with Lists in Reference Manual, and your settings is no problem.SD2 signals are connected to SD connector, I couldn't confirm if SD / eMMC card inserted supports eMMC DDR mode.

So my suggestion is :

    On i.MX6Q SabreSDP board, eMMC is supported, and it is connected to SD4 port, you can test it.  See below , please!

(1) Populate R712 to Board.

(2) Setting Pin 4 & Pin3 on SW6 to be 10 for x8 or 01 for x4 mode.

Have a nice day!

NXP TIC weidong sun