topic Re: Correct IMX8 processor reference manual? in i.MX Processors

Correct IMX8 processor reference manual?

jcole1 — Mon, 16 Sep 2019 11:43:39 GMT

I have downloaded the IMX8 processor reference manual in order to access some of the GPIO registers in a device driver.

The document I used was this one:

https://www.nxp.com/docs/en/reference-manual/IMX8DQXPRM.pdf

According to the above, the GPIO registers are in the region of 0x5D080000, however attempting to access them causes GPFs.

I consulted a manual for the IMX7 where the registers are in the region of 0x30200000 and they appear to work.

The CPU is on a SOM made by Compulab; the cl-som-imx8

The cpuinfo on the target displays 4 processors:

# cat /proc/cpuinfo
processor : 0
BogoMIPS : 16.66
Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
CPU implementer : 0x41
CPU architecture: 8
CPU variant : 0x0
CPU part : 0xd03
CPU revision : 4

Are there variations amongst the IMX8 family or is there a different reference manual available?

Re: Correct IMX8 processor reference manual?

Rita_Wang — Wed, 18 Sep 2019 03:35:00 GMT

Different products have they own RM, all the i.MX8 series products are here. The i.MX8&i.MX8X are still on PRE-PRODUCTION.

Re: Correct IMX8 processor reference manual?

jcole1 — Wed, 18 Sep 2019 09:03:30 GMT

I see - I have found this one for the iMX8MM, which is very different to the DQ/XP:

https://cache.nxp.com/secured/assets/documents/en/reference-manual/IMX8MMRM.pdf

Are there any others?

Jase

Re: Correct IMX8 processor reference manual?

jcole1 — Wed, 18 Sep 2019 16:29:30 GMT

I am also experiencing difficulty accessing the I2C registers (0x30A20000 etc). I use the same mechanism as I do for accessing the GPIO and IOMUX registers, and they all work
e.g:

define I2C3_CR 0x30A40008

static void __iomem *vpIMX8_I2C3_CR;

vpIMX8_I2C3_CR = devm_ioremap(thisDev, I2C3_CR, sizeof(u16));

readVal = ioread16 (vpIMX8_I2C3_CR); //system hangs here......

Is there anything I am doing wrong here?

Re: Correct IMX8 processor reference manual?

Rita_Wang — Thu, 19 Sep 2019 02:50:42 GMT

Yes, the i.MX8DQ/XP is different with the i.MX8MM. They are different products.

Re: Correct IMX8 processor reference manual?

Rita_Wang — Thu, 19 Sep 2019 02:52:20 GMT

Could you tell us which product are you using?

Re: Correct IMX8 processor reference manual?

jcole1 — Thu, 19 Sep 2019 09:43:06 GMT

Hi - it is this one - the C1500Q:

https://www.compulab.com/products/computer-on-modules/cl-som-imx8-nxp-i-mx-8-system-on-module-computer/#specs

Re: Correct IMX8 processor reference manual?

jcole1 — Thu, 19 Sep 2019 15:59:17 GMT

It's possible that this issue could be DTS-related; I have one kernel image where this issue occurs, on another it does not.

Re: Correct IMX8 processor reference manual?

Rita_Wang — Fri, 20 Sep 2019 03:53:37 GMT

Hi Jason,

I see that you are using the third company board, so about the software and board information you can contact their supportWelcome to CompuLab Support | CompuLab .

Have a nice day

Rita

Re: Correct IMX8 processor reference manual?

jcole1 — Fri, 20 Sep 2019 09:22:57 GMT

Wow. I am astonished and dismayed.

It may be a third party board, but it is using your CPU (iMX8MM)

Perhaps you could take a leaf from the TI forum where they would answer questions on their products irrespective of how they are deployed.

Re: Correct IMX8 processor reference manual?

Rita_Wang — Sat, 21 Sep 2019 03:13:07 GMT

Hi Jason,

So sorry that my reply make you dismayed. Here I mean the software and board information you can contact the third company, because the hardware and software are design by them they will give more effective and fast reply. I see your above information, one image is work well, another not, so the hardware is OK. About the chip questions you can contact us.

Have an nice day

Best Regards

Rita