[v3, 0/7] Add SD UHS-I and eMMC HS200 support for eSDHC

Yangbo Lu yangbo.lu at nxp.com
Mon Mar 27 00:49:35 PDT 2017

It's complicated to support SD UHS-I and eMMC HS200 for eSDHC because
there're many differences between eSDHC and SD/eMMC spec. Several
differences as below must be considered:
1. Peripheral clock must be used instead of platform clock.
    - eSDHC could select peripheral clock or platform clock as its clock
      source. According to RM, UHS-I/HS200 must use peripheral clock since
      it supports higher frequency than platform clock.
    - Patch 1 and patch 6 is to support this.
2. Signal voltage switching requires a control circuit out of eSDHC.
    - eSDHC supports signal voltage switch from 3.3v to 1.8v by
      eSDHC_PROCTL[VOLT_SEL] bit. This bit changes the value of output
      signal SDHC_VS, and there must be a control circuit out of eSDHC
      to change the signal voltage according to SDHC_VS output signal.
    - Patch 2 is to support this.
3. eSDHC uses tuning block for tuning procedure.
    - Tuning clock control register must be configured before tuning.
    - Patch 3 is to support this.
4. Delay is needed between tuning cycles for HS200 tuning.
    - Once a patch removed mdelay between tuning cycles.
      But eSDHC needs it.
    - Patch 4 and patch 5 is to support this.
5. UHS-I/HS200 modes could be enabled in dts node.
    - Patch 7 is to support this.

Please review and merge these patches on mmc git tree if no changes
are required.

Adrian Hunter (1):
  mmc: sdhci: Control the delay between tuning commands

Yangbo Lu (6):
  mmc: sdhci-of-esdhc: add peripheral clock support
  mmc: sdhci-of-esdhc: add support for signal voltage switch
  mmc: sdhci-of-esdhc: add tuning support
  mmc: sdhci-of-esdhc: add delay between tuning cycles
  arm64: dts: ls1046a: add clocks property and compatible for eSDHC node
  arm64: dts: ls1046ardb: add MMC HS200/UHS-1 modes support

 arch/arm64/boot/dts/freescale/fsl-ls1046a-rdb.dts |   8 ++
 arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi    |   3 +-
 drivers/mmc/host/sdhci-esdhc.h                    |   7 +
 drivers/mmc/host/sdhci-of-esdhc.c                 | 165 +++++++++++++++++++++-
 drivers/mmc/host/sdhci.c                          |  11 +-
 drivers/mmc/host/sdhci.h                          |   2 +
 6 files changed, 190 insertions(+), 6 deletions(-)


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