Hi Fabio,

Hi Peng,

On Mon, Apr 15, 2019 at 10:33 PM Peng Fan peng.fan@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.fan@nxp.com

This is actually a resend of https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatc

hwork.ozlabs.org%2Fpatch%2F1018188%2F&amp;data=02%7C01%7Cpeng.fa n%40nx

...

p.com%7C49da3f56664f4651249e08d6c20c0a55%7C686ea1d3bc2b4c6fa92c d99c5c3

...

01635%7C0%7C0%7C636909754297976230&amp;sdata=ENHPWHJbIZYQPgB 92hbNTROiA

...

TEML7yYJMNGxHwtHkw%3D&amp;reserved=0 which got no response. Rebased on master.

drivers/mmc/Kconfig | 12 ++++++++ drivers/mmc/mmc-uclass.c | 15 +++++++++ drivers/mmc/mmc.c | 79

+++++++++++++++++++++++++++++++++++++++++++++++-

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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?

This patch is just a resend which got no response since first posted in 2018/12.

The support on i.MX8 will be posted, if there is no major comments on the common code part.

Thanks, Peng.

Otherwise it will be just dead code.

Thanks