topic Re: LS1046 I2C problem in Layerscape

LS1046 I2C problem

gaborkocsis — Tue, 18 Dec 2018 09:54:05 GMT

Hello Everybody,

We have made our own custom board based on a LS1046A. LS1046A has four I2C buses. The first works well, but the other three doesn't. In the RCW I've set the appropriate bits to their proper values (Bits 445-447, IIC_EXT field).

Despite of this the I2C2 / I2C3 / I2C4 doesn't work. In the U-BOOT I tried to scan the I2C buses. On the I2C1 the installed devices can be seen, but on the others they can't be seen.

On the I2C buses we have installed some temperature sensors, their addresses are setup correctly, there can't be address conflicts.

For example I tried the followings:

=> i2c dev 2
Setting bus to 2
=> i2c probe
Valid chip addresses:wait_for_sr_state: Arbitration lost sr=92 cr=0 state=2020
i2c_init_transfer: failed for chip 0x0 retry=0
wait_for_sr_state: Arbitration lost sr=92 cr=0 state=2020
i2c_init_transfer: failed for chip 0x0 retry=1
wait_for_sr_state: Arbitration lost sr=92 cr=0 state=2020
i2c_init_transfer: failed for chip 0x0 retry=2
i2c_init_transfer: give up i2c_regs=0x21a0000

Where do I have to setup something?

(I've read the QorIQ-SDK-2.0-1703 but I couldn't find relevant info for this problem)

Thanks in advance,

Gabor

Re: LS1046 I2C problem

ufedor — Wed, 19 Dec 2018 02:23:05 GMT

1) Concerning IIC2

Which RCW source is used?

The selection of the SD card for an RCW/PBI source makes the secondary function (SDHC IO's such as SDHC_CD_B, SDHC_WP) available on the I2C2 interface pins, and hence, the I2C2 interface is not available in this configuration.

Additional information can be provided in a Technical Case:

   open www.nxp.com
   Select "Support" -> "All Support Options"
   Click "Go to Tickets"
   Log in with your NXP login and password
   On the "Group, Create and View your support cases" page press "+ Add a new case" to start the process.

2) Concerning IIC3 & 4

What is the SCFG_RCWPMUXCR0 value?

Re: LS1046 I2C problem

gaborkocsis — Wed, 19 Dec 2018 09:07:23 GMT

Hello,

thank you for your quick answer.

The value of SCFG_RCWMUXCR0 was 00330000 and when I set it to 0 the IIC3 started to work.

Concerning with IIC4 I don't know since I couldn't try it so far but I thin so it will work.

But the IIC2....the RCW source is SDHC/MMC, the physical boot source is an eMMC chip that doesn't use the SDHC_CD_B, SDHC_WP

so I thought they could be used for IIC2 and I set the IIC_EXT field in the RCW to use those signals as IIC SDA && SCL.

Thank for your help

Gabor

Re: LS1046 I2C problem

ufedor — Wed, 19 Dec 2018 09:45:17 GMT

1) The selection of the SD card for an RCW/PBI source makes the secondary function (SDHC IO's such as SDHC_CD_B, SDHC_WP) available on the I2C2 interface pins, and hence, the I2C2 interface is not available in this configuration.

Additional information can be provided in a Technical Case: