Hebbar, Gururaja cd587096c0 mmc: omap_hsmmc: Enable HSPE bit for high speed cards
HSMMC IP on AM33xx need a special setting to handle High-speed cards.
Other platforms like TI81xx, OMAP4 may need this as-well. This depends
on the HSMMC IP timing closure done for the high speed cards.

From AM335x TRM (SPRUH73F - 18.3.12 Output Signals Generation):

The MMC/SD/SDIO output signals can be driven on either falling edge or
rising edge depending on the SD_HCTL[2] HSPE bit. This feature allows
to reach better timing performance, and thus to increase data transfer
frequency.

There are few pre-requisites for enabling the HSPE bit
- Controller should support High-Speed-Enable Bit and
- Controller should not be using DDR Mode and
- Controller should advertise that it supports High Speed in
  capabilities register and
- MMC/SD clock coming out of controller > 25MHz

Signed-off-by: Hebbar, Gururaja <gururaja.hebbar@ti.com>
Signed-off-by: Venkatraman S <svenkatr@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2012-12-06 13:54:56 -05:00
..
2012-10-10 10:58:42 +09:00
2011-12-07 22:02:05 +00:00
2012-10-10 10:58:42 +09:00
2012-12-06 13:54:54 -05:00
2012-09-04 13:58:29 -04:00
2009-03-24 21:30:03 +01:00
2012-12-06 13:54:44 -05:00
2012-09-20 14:54:57 -07:00
2012-10-10 10:58:42 +09:00
2009-10-01 16:11:15 -07:00
2012-11-07 15:02:03 -05:00
2012-12-06 13:54:51 -05:00
2012-10-11 10:21:48 +09:00
2012-10-10 10:58:42 +09:00