Are there any configuration settings needed to make memtool work on the i.MX51 and i.MX53 processors?

[joemehigen]

We can see the i/o has been memory mapped ok, but memtool always encounters a BUS ERROR trying to access  the GPIO registers.

We're in the process of upgrading Linux from 2.6.35 to 3.14.33.

tls450# cat /proc/iomem

50008000-5000bfff : mmc0

53f80800-53f809ff : /soc/aips@50000000/usbmisc@53f80800

53f84000-53f87fff : /soc/aips@50000000/gpio@53f84000

53f88000-53f8bfff : /soc/aips@50000000/gpio@53f88000

53f8c000-53f8ffff : /soc/aips@50000000/gpio@53f8c000

53f90000-53f93fff : /soc/aips@50000000/gpio@53f90000

53f98000-53f9bfff : /soc/aips@50000000/wdog@53f98000

53fa8000-53fabfff : /soc/aips@50000000/iomuxc@53fa8000

53fb4000-53fb7fff : /soc/aips@50000000/pwm@53fb4000

53fb8000-53fbbfff : /soc/aips@50000000/pwm@53fb8000

53fc0000-53fc3fff : imx-uart

53fdc000-53fdffff : /soc/aips@50000000/gpio@53fdc000

53fe0000-53fe3fff : /soc/aips@50000000/gpio@53fe0000

53fe4000-53fe7fff : /soc/aips@50000000/gpio@53fe4000

53fec000-53feffff : /soc/aips@50000000/i2c@53fec000

63fb0000-63fb3fff : 63fb0000.sdma

63fc4000-63fc7fff : /soc/aips@60000000/i2c@63fc4000

63fec000-63feffff : /soc/aips@60000000/ethernet@63fec000

70000000-efffffff : System RAM

  70008000-70749f33 : Kernel code

  70780000-70d238e7 : Kernel data

f8000000-f801ffff : /soc/sram@f8000000

[fabio_estevam]

Hi Joe,

Maybe you could try devmem2 utility for reading the registers?

Take a look at:

http://www.element14.com/community/thread/32436/l/gpio-ports-on-riot-board?displayFullThread=true

Regards,

Fabio Estevam

[joemehigen]

Hi Fabio,

Thanks for the suggestion.

I still get the same results trying to access a GPIO register.

joe# ./devmem2 0x53f84000

/dev/mem opened.

Memory mapped at address 0x76f8d000.

Bus error

I'll keep investigating.

Thanks again.

Joe

[fabio_estevam]

Hi Joe,

What is the specific register you are trying to access and which SoC (mx51 or mx53)?

Regards,

Fabio Estevam

[joemehigen · Accepted solution]

Hi Fabio,

I use memtool to access the GPIO and IOMUX registers, makes it easy to setup pad controls and the like.

I created a simple kernel driver to read and write the registers via IOCTLs, and that's working fine.

I plan to look and see how the driver's ioremap differs from mmaps, but development is back on track with this work around.

Thanks

Joe

[joemehigen]

The memtool problem occurs on the 2.6 kernel as well as the 3.14 kernel.  It seems to be related to mapping i/o memory.

running memtool on either kernel to an area described in /proc/iomem results in a bus error.

It's more noticeable in the 3.14 kernel because the gpio and iomux areas are now mapped.

Will continue to investigate further.

[igorpadykov]

Hi JOE

I think one can try with i.mx53qsb yocto demo images

Public images - fsl-community-bsp/master/440/framebuffer/imx53qsb

Index of /releases/yocto/yocto-1.6/machines/imx53qsb

Best regards

igor

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[joemehigen]

That was our next idea, thanks for the response.

[joemehigen]

The images on the two links seem to use the 2.6.35 kernel and boot loader, which we have working.

We're trying to upgrade to the 3.14.33 kernel.

I suspect we're having issues setting up the device tree correctly.

Are there images available with a newer kernel?

[igorpadykov]

Hi JOE

I think you can try below steps

[Share] How to make memtool accessing the WEIM registers success in iMX25 Linux BSP

Best regards

igor

[joemehigen]

Hi Igor,

A quick update, some portions of the chip are accessed fine via memtool.

For instance, the IPU can be read and written fine.

tls450#  memtool 1e04000c 1

Reading 0x1 count starting at address 0x1E04000C

0x1E04000C:  20F90000

tls450#  memtool 1e04000c=20F90000

Writing 32-bit value 0x20F90000 to address 0x1E04000C

I'll check out the link above.

Thanks

Joe