topic Re: How to enable SPI wait state in i.MX Processors

How to enable SPI wait state

hillcoder — Thu, 10 Jun 2021 13:06:17 GMT

Hi to all,

I'm working on a linux system running on a board based on imx6q dual.

I need to put some wait states in my SPI communication. From datasheet I read that for do this I have to write in to the ECSPIx_PERIODREG register.

Below the code that I added at the end on mx51_ecspi_config functio on spi-imx.c:

period = readl(spi_imx->base + MX51_ECSPI_PERIOD);
period = 0x800F;
printk("period %x\n",period);
writel(period, spi_imx->base + MX51_ECSPI_PERIOD);
period = readl(spi_imx->base + MX51_ECSPI_PERIOD);
printk("period %x\n",period);

Also if the written value is right no wait states between words appears...

Where I have wrong ?

Many thanks

Re: How to enable SPI wait state

hillcoder — Thu, 10 Jun 2021 13:46:55 GMT

I made a mistake...

my code is :

period = readl(spi_imx->base + MX51_ECSPI_PERIOD);
period = 0x16;
printk("period %x\n",period);
writel(period, spi_imx->base + MX51_ECSPI_PERIOD);
period = readl(spi_imx->base + MX51_ECSPI_PERIOD);
printk("period %x\n",period);

Re: How to enable SPI wait state

igorpadykov — Mon, 21 Jun 2021 01:01:13 GMT

Hi Hill

what bsp used in the case, may be recommended to try with latest nxp release :

https://source.codeaurora.org/external/imx/linux-imx/tree/?h=lf-5.10.y

https://source.codeaurora.org/external/imx/imx-test/tree/test/mxc_spi_test?h=lf-5.10.y_1.0.0

Documentation :

https://www.nxp.com/design/software/embedded-software/i-mx-software/embedded-linux-for-i-mx-applications-processors:IMXLINUX?tab=In-Depth_Tab

Best regards
igor