On Sun, Aug 06, 2023 at 10:44:21PM +0200, Linus Walleij wrote: > On Sun, Aug 6, 2023 at 1:48 PM Ladislav Michl <oss-lists@xxxxxxxxx> wrote: > > > How do we get there? > > ff4143ccff31 ("MIPS: Octeon: cavium_octeon_defconfig: Enable Octeon MMC") > > enabled MMC driver, but left MMC_BLOCK_BOUNCE disabled, although driver > > performace depends on it. > > Ooops. > > > c3dccb74be28 ("mmc: core: Delete bounce buffer Kconfig option") > > Added MMC_CAP_NO_BOUNCE_BUFF to the caps, based on assumption it should > > be there as MMC_BLOCK_BOUNCE is disabled in defconfig > > de3ee99b097d ("mmc: Delete bounce buffer handling") > > finally removed all bounce buffer handling as almost nothing needs that. > > > > Sadly, 70XX SoC cannot do SG, so it suffers a lot. Strangely enough, > > above patches are either authored or suggested by Cavium's employees. > > > > So, given the number of affected SoC and before cooking driver specific > > solution, are we sure we indeed do not want some generic one? > > So you are talking about something along the lines of: > > commit bd9b902798ab14d19ca116b10bde581ddff8f905 > Author: Linus Walleij <linus.walleij@xxxxxxxxxx> > Date: Mon Jan 29 00:44:53 2018 +0100 > > mmc: sdhci: Implement an SDHCI-specific bounce buffer > > ? Yes, this is the exact commit I had in mind :) > Yeah I guess that if this is needed by more than one driver it > should be made into a library, or say a piece of code turned on by > a config option that the dependent drivers select. > > Interested in the job? :D Interested is not the word I'd use, but yes, I'll give it a try making it a little more generic solution. > Yours, > Linus Walleij Best reards, ladis