AnsweredAssumed Answered

EPIT support IMX6SX

Question asked by Alan Casinelli on Nov 25, 2015

Hello everyone,
I'm starting developing an application on an imx6sx-sabre-sd like board. I need to collect data from an adc converter every 3microseconds through using an SPI connection.
My kernel version is linux 3.10.53. I've already read this thread: GPT as system timer, EPIT as user timer, but the boot will hang at "Starting Kernel...".

I've also tried to use the timer linux has to offer, but they really can't meet the requirements i need.

 

Am I missing something obvious?

 

You can find attached the patch I made based on the thread i quoted, and the u-boot log.

 

 

Thanks for your help.

 

EDIT:
I actually made the EPIT working by deleting every reference to one of the epit timers in clk-imx6sx.c. Now i can see the timer ticking downward to 0 and then reset to the value in the LR Register. I also enabled the OCIEN bit in the epit.c. Still I cannot seem to generate an interrupt as the gpio I'm trying to drive is not toggling. Also if I use memtool on the address 0x20d4000 (the epit2 register) I can see that the OCIEN bit is disabled. I'll keep digging into it and edit if I have new informations.

Original Attachment has been moved to: 0001-Add-epit-timer-support.patch.zip

Original Attachment has been moved to: u-boot-log.txt.zip

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