[PATCH 4/6] mmc: sdhci-esdhc-imx: config watermater levles and burst lengths
eric.nelson at boundarydevices.com
Wed Jun 10 07:36:00 PDT 2015
On 06/10/2015 01:50 AM, Haibo Chen wrote:
> i.MX7D support eMMC HS400 mode, this mode can run in 8 bit,200MHZ
> DDR mode. So the I/O speed improve a lot compare to SD3.0
> The default burst length is 8, if we don't change this value, in
> HS400 mode, when we do eMMC read operation, we can find that the
> clock signal will stop for a period of time. This means the speed
> of data moving on AHB bus is slower than I/O speed. So we should
> improve the speed of data moving on AHB bus.
> For imx7d usdhc, this patch set the burst length as 16, and set
> watermater levle as 64. The test result is the clock signal has
> no stop during the eMMC HS400 operation. For other imx usdhc, remain
"watermark", not "watermater".
> the default value: burst length as 8, watermater level as 16.
Same goes for the subject.
Also "levels", not "levles", so:
mmc: sdhci-esdhc-imx: config watermark level and burst length
More information about the linux-arm-kernel