On 2023/4/11 2:04, Shengyu Qu wrote: > Hello William, > >> On 2023/3/29 0:08, Shengyu Qu wrote: >>> Hello William, >>> >>> Sorry for making noise about this, but seems deleted voltage swtich function >>> >>> doesn't help about this. But there's still a problem about eMMC speed. Currently >>> >>> only about 20MB/s maximum reading speed could be reached when using eMMC >>> >>> on VF2, any idea about this? >>> >>> Best regards, >>> >>> Shengyu >>> >>> 在 2023/3/28 0:01, Shengyu Qu 写道: >>>> Hello William, >>>> >>>> I'm digging into downstream mmc driver these days and found a problem >>>> >>>> that current version mainline driver doesn't has a voltage switch function for >>>> >>>> it. Downstream older version has one but was deleted in this commit [1]. >>>> >>>> It was deleted since vf2's SD slot doesn't have 1.8V input but commiter forgot >>>> >>>> that vf2's eMMC slot has a proper 1.8V input. >>>> >>>> So could you add voltage switch function for mainline? I've met a eMMC speed >>>> >>>> problem possibly due to it. >>>> >>>> Best regards, >>>> >>>> Shengyu >>>> >> >> Hi Shengyu, >> >> Sorry for the late reply. >> >> First of all, I will consider adding voltage switch function, but the implementation >> method is to configure the pmic register configuration in dts, and the implementation >> interface will use the voltage switch function in dw_mmc.c. >> >> As for speed, the main reason for the low rate is the clock of JH7110 and the >> associated IO driving strength, in this limit, the maximum reading speed I tested was >> about 50Mb/s. >> >> I will try to reproduce your problem and try to solve it. Thanks for suggestions. >> >> Best regards, >> William > I found out the reason and fixed that. dmwci driver needs vqmmc supply > configured in device tree and a successful voltage change to actually > enable 1.8v mode, even 1.8 supply actually already physically exists. > So to solve this problem, I wrote AXP15060 driver and device tree > bindings basing on -upstream branch and gets over 75MB/s read speed. The > driver series is already under review here: > > https://lore.kernel.org/all/TY3P286MB26117891DFB2DD615A7C54EF98969@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ > > Best regards, > Shengyu Hi Shengyu, Thanks for the patch series. I will try it on my branch. Best regards, William
