On 22 December 2015 at 19:40, Lucas Stach <dev@xxxxxxxxxx> wrote: > Hi all, > > this series implements UHS-I signaling for the Tegra SDHCI host, > which mainly means putting a proper tuning sequence in place. > > I've tested this on Jetson TK1 and got the following speed results, > where mmcblk0 is the on-board eMMC and mmcblk1 is a micro SDXC card: > > Without series applied: > hdparm -t /dev/mmcblk0 > Timing buffered disk reads: 110 MB in 3.05 seconds = 36.02 MB/sec > hdparm -t /dev/mmcblk1 > Timing buffered disk reads: 56 MB in 3.01 seconds = 18.63 MB/sec > > With series applied: > hdparm -t /dev/mmcblk0 > Timing buffered disk reads: 236 MB in 3.00 seconds = 78.58 MB/sec > hdparm -t /dev/mmcblk1 > Timing buffered disk reads: 102 MB in 3.04 seconds = 33.51 MB/sec > > Tegra 30 does support UHS-I speeds too, but currently has problems > when lowering the card voltage, which is needed in order to switch > to UHS-I signaling. I have some more patches to fix this, but they > need a bit more cleanup, with them applied the gains on Tegra30 are > similar to the results above. > > For now the gains are limited to Tegra124+, with no regressions on > Tegra30 and Tegra20. > > V2 fixes some minor style problems and is rebased on top of mmc/next. > This means it enables the same tuning logic on Tegra210 also. I > don't have a way to test this myself, so any testing on Tegra210 much > appreciated. > > Regards, > Lucas > > Lucas Stach (5): > mmc: tegra: implement module external clock change > mmc: tegra: disable SPI_MODE_CLKEN > mmc: tegra: implement UHS tuning > mmc: tegra: enable UHS-I modes > mmc: tegra: use correct accessor for misc ctrl register > > drivers/mmc/host/sdhci-tegra.c | 166 ++++++++++++++++++++++++++++++++++------- > 1 file changed, 138 insertions(+), 28 deletions(-) > Thanks, applied for next! Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
