Hi Peng, On Mon, Apr 15, 2019 at 10:33 PM Peng Fan <peng....@nxp.com> wrote: > > eMMC 5.1+ supports HS400 Enhances Strobe mode without the need for > tuning procedure. > The flow is as following: > - set HS_TIMIMG (Highspeed) > - Host change freq to <= 52Mhz > - set the bus width to Enhanced strobe and DDR8Bit(CMD6), > EXT_CSD[183] = 0x86 instead of 0x80 > - set HS_TIMING to 0x3 (HS400) > - Host change freq to <= 200Mhz > - Host select HS400 enhanced strobe complete > > Signed-off-by: Peng Fan <peng....@nxp.com> > --- > > This is actually a resend of https://patchwork.ozlabs.org/patch/1018188/ > which got no response. > Rebased on master. > > > drivers/mmc/Kconfig | 12 ++++++++ > drivers/mmc/mmc-uclass.c | 15 +++++++++ > drivers/mmc/mmc.c | 79 > +++++++++++++++++++++++++++++++++++++++++++++++- > include/mmc.h | 15 +++++++++ > 4 files changed, 120 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/Kconfig b/drivers/mmc/Kconfig > index 04a4e7716f..3ef7580a43 100644 > --- a/drivers/mmc/Kconfig > +++ b/drivers/mmc/Kconfig > @@ -111,6 +111,18 @@ config SPL_MMC_UHS_SUPPORT > cards. The IO voltage must be switchable from 3.3v to 1.8v. The bus > frequency can go up to 208MHz (SDR104) > > +config MMC_HS400_ES_SUPPORT > + bool "enable HS400 Enhanced Strobe support" > + help > + The HS400 Enhanced Strobe mode is support by some eMMC. The bus > frequency is up to > + 200MHz. This mode does not tune the IO.
Is there any board that can select this option? Otherwise it will be just dead code. Thanks _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
