AM1808 SPI Problem

TommyG

Other Parts Discussed in Thread: OMAP-L138

Using the Arago repository, branch remotes/origin/03.21.00.05 with LogicPD EVM

I have configured jffs2 to have a MTD based on the ST m25p80 spi flash on the baseboard of the LogicPD eval board (CONFIG_MTD_M25P80) .

When linux comes up it tries to initialize the serial flash by first reading the device id. This happens in the function jedec_probe ( drivers/mtd/devices/m25p80.c). This function calls spi_write_then_read with the a opcode of 0x9f (OPCODE_RDID) which should reads the id. This function should return 5 bytes from the device which indicates the id. For this device it should return 0x202024, instead it returns 0xffffffff. This leads me to believe that we have some sort of clocking or configuration issue. I have reviewed the data structures in arch/arm/mach-davinci/board-da850-evm.c ( da850evm_spi1_pdata, da850evm_spiflash_data, da850evm_spiflash_cfg, and da850evm_spi_info). Theses structure control the configuration of this spi interface. It look good to me.

How can I resolve this issue?

Regards.

over 14 years ago

0 Sudhakar Rajashekhara over 14 years ago

TI__Expert 5170 points

Hi,

Are you seeing the same behavior with PSP Release 03.21.00.04(http://software-dl.ti.com/dsps/dsps_public_sw/psp/LinuxPSP/DaVinci_03_21/03_21_00_04/index_FDS.html)? Can you send across the complete booting log where you are seeing this message?

Regards, Sudhakar

0 TommyG over 14 years ago in reply to Sudhakar Rajashekhara

TI__Genius 13045 points

Will try new PSP you point to and get the log. Will come back when done.

Thanks.

0 TommyG over 14 years ago in reply to TommyG

TI__Genius 13045 points

Sudhakar,
Attached is the log. Will test new PSP as soon as possible.

Thanks.

Boot Log 110714.rtf

0 TommyG over 14 years ago in reply to TommyG

TI__Genius 13045 points

Sudhakar,

Here is feedback on PSP results.

PSP03.20.00.14: working ok
PSP03.21.00.04: not working
PSP03.21.00.04: not working

Seems like issue was introduced in release PSP03.21.xx.xx.

Any feedback on the log data?

Thanks.

0 Sudhakar Rajashekhara over 14 years ago in reply to TommyG

TI__Expert 5170 points

Hi,

While going through the log data I observed few things:

Log shows that there is a I2C EEPROM at 0x50. Logic PD boards do not have I2C EEPROM. Are you using Spectrum Digital board?
I have attached the log data I got from my testing. Compared to your log, I see some differences in some places . Have you modified the code?

I am using the latest 03.21.00.05 branch from arago and tested it on Spectrum Digital AM18x EVM. Linux Kernel was able to identify the SPI flash. Please see the attached log. Is SPI flash getting detected from U-Boot?

Regards, Sudhakar

0 TommyG over 14 years ago in reply to Sudhakar Rajashekhara

TI__Genius 13045 points

Sudhakar,
Sorry about the delay in response.

When converted to PSP03.21.00.05 copied the old kernel config file into the new kernel directory. This seems to break the SPI. Found that if I used the da850_omap138_defconfig the SPI works. Added in the things that were needed. The first was the NOR MTD, wheich required to disable the MMC/SD/SDIO drivers. With this done the NOR and SPI mtd's both work fine. The next step is to enable the RMII which disables the MII network interface. When this was done, the SPI stops working, in the same way it had. When the SPI MTD tries to read the SPI device id it returns 0xffffffff. The SPI command completes with no errors, but the data is incorrect. The kernel config variable that I set is CONFIG_DA850_UI_RMII.

Attached is config file and startup log (with and without RMII configured).

Having both SPI flash and RMII is a requirement for design

Like you mention system seems to detect a i2c eeprom. This is not the Spectrum Digital board.

Regards.

log.zip

0 Sudhakar Rajashekhara over 14 years ago in reply to TommyG

TI__Expert 5170 points

Hi,

I tested RMII interface on OMAP-L138 using 03.20.00.14 release and I also noticed that SPI flash gets detected but I was not able to erase/mount the SPI flash partition. Can you check whether you are able to do I/O when SPI flash gets detected with RMII enabled?

I believe SPI flash not getting detected with RMII is a known issue as discussed at http://e2e.ti.com/support/embedded/int-embedded_software/f/118/p/126379/457717.aspx#457717.

Thanks, Sudhakar

0 TommyG over 14 years ago in reply to Sudhakar Rajashekhara

TI__Genius 13045 points

Sudhakar,

Thanks. Will check and get back to you.

Regards.

0 Samuel Rule over 13 years ago in reply to Sudhakar Rajashekhara

Prodigy 235 points

Has anyone found a solution to this? I am having the same issue where I request the id from the SPI chip, I just get all 0xFF values. I tried disabling the RMII altogether because I have no need for networking stuff at all, but that didn't help.

Sudhakar,

The link you provided doesn't says "Group Not Found"

Sam

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AM1808 SPI Problem