spi nor flash boot

[xiaoqiangyang]

Hi all.

I am working on i.MX6 SABRE-SD board and want to boot from spi nor flash. But the guide doesn't mention this way. Now I wonder if it supports this way.

Anyone can help me? Thanks in advance!

Xiaoqiang

[BiyongSUN]

Hi Xiaoqiang,

IMX6 can support  spi nor boot with BOOT_CFG1[7:4] = 0000.

But Current SD board uses KEY relative PINs as

SPI interface. However, this set of PINs are not

supported by ROM. Therefore, SPI NOR boot is

not supported by Smart Device Board.

You can check the Sabre-AI board for reference. Sabre-AI board supports SPI NOR boot.

Regards,

Biyong

[caoping]

Hi  Biyong,

         now i want to  design one board use SPI NOR boot  similar to Sbare-AI board,EIM pin that i have used. the pin i use is diffrent from Sbare-AI board,so i want to do some modify on linux which run in ram,can you tell me some idea about this? Thank you !

[BiyongSUN · Accepted solution]

Hi Cao ping,

In the imx6q reference manual:

Serial ROM through SPI and I2C-->Serial ROM eFUSE Configuration

                                               ->ECSPI Boot

                                                   --> ECSPI IOMUX Pin Configuration

After you have read the referece manual, let take the AI board hardware as an example:

SPI_NOR 0 0 1 1 x x x x x x x x x x x x 0 0 0 0 0 0 0 0 x x 0 1 1 0 0 0

BT_CFG1_=0011xxxx

BT_CFG4_=xx011000

According to Table 8-22. Serial ROM Boot eFUSE Descriptions

BT_CFG1:    0011        Boot from Serial ROM

BT_CFG4:    xx011000:

BOOT_CFG4[5:4]=01   CS select (SPI only) 01 - ECSPIx_SS1

BOOT_CFG4[3] =1      1 - 3-bytes (24-bit)

BOOT_CFG4[2:0]=000 -  ECSPI-1

According to Table 8-25. SPI IOMUX Pin Configuration, the pins are:

MISO   EIM_D17.alt1, MOSI   EIM_D18.alt1, SS1 EIM_D19.alt1, SCLK EIM_D16.alt1

Then you can check the schematics of AI board whether it is our expectation.

Yes, it is.

So, you can use ECSPI-1 ECSPI-2 ECSPI-3 ECSPI4 ECSPI-5 for SPI boot.

But please make use on collisions happen.

You can use the iomux tool to do the check.

Biyong

Biyong

[xiaoqiangyang]

Hi Biyong,

Thanks for your explanation. As you said，the IMX6  processor supports SPI NOR boot but the Smart Device Board  can not. If I desing my own board, I can add SPI NOR boot to my design, right?

[BiyongSUN]

Hi Xiaoqiang,

Correct. You can add the SPI-NOR boot to your board as Sabre-AI does. You can compare  Sabre-AI board to Sabre-SD board to find the differences.

Those differences are what you need to do on your board.

Regards,

Biyong