[U-Boot] [PATCH v2 00/11] Improvements on the MMC switch

[Jean-Jacques Hiblot]

This series brings some improvements related to the switch command:
- use timeouts specified in the EXT_CSD instead of fixed values
- retry switching partitions a few time before calling it a failure
- make switching mode more reliable by checking the status of operation
  afterward.
- make switching faster by using the DAT0 line as a ready/busy signal
- Allow HS200/H400 modes with boot partitions. That didn't work well before
  because the switch was not reliable enough.

This has been tested on DRA76-evm and beaglebone black.
Travis build: https://travis-ci.org/jjhiblot/u-boot/builds/553183341

Changes in v2:
- update commit log to warn that the CLK must not be turned off while
  polling on DAT0
- rebase on latest u-boot (did not apply as-is)

Jean-Jacques Hiblot (11):
  mmc: omap_hsmmc: reset FSM for DAT and CMD lines if needed before a
    new command
  mmc: omap_hsmmc: don't fill the send_init_stream callback
  Revert "mmc: Add a new callback function to perform the 74 clocks
    cycle sequence"
  mmc: omap_hsmmc: provide wait_dat0 even if UHS modes are not supported
  mmc: add mmc_poll_for_busy() and change the purpose of
    mmc_send_status()
  mmc: if possible, poll the busy state using DAT0
  mmc: use the generic timeout for cmd6 (SWITCH) provided in the ext_csd
  mmc: When switching partition, use the timeout specified in the
    ext_csd
  mmc: During a switch, poll on dat0 if available and check the final
    status
  mmc: do not change mode when accessing a boot partition
  mmc: retry a few times if a partition switch failed

 drivers/mmc/mmc-uclass.c  |  15 ----
 drivers/mmc/mmc.c         | 169 +++++++++++++++++++++-----------------
 drivers/mmc/mmc_private.h |   9 +-
 drivers/mmc/mmc_write.c   |   4 +-
 drivers/mmc/omap_hsmmc.c  |  26 ++----
 include/mmc.h             |  19 ++---
 6 files changed, 115 insertions(+), 127 deletions(-)

-- 
2.17.1