[PATCH v5 0/6] mmc: add support for BST C1200 SDHCI controller

[Ulf Hansson]

On Fri, 23 Jan 2026 at 10:53, Albert Yang <yangzh0906 at thundersoft.com> wrote:
>
> This series adds MMC/eMMC controller support for Black Sesame Technologies
> C1200 SoC. BST is a leading automotive-grade computing SoC provider focusing
> on intelligent driving, computer vision, and AI capabilities for ADAS and
> autonomous driving applications. More information: https://bst.ai
>
> == Background ==
>
> This is the MMC portion split from the original v4 series [1] following
> feedback from Arnd Bergmann [2]. The platform support (vendor-prefix,
> SoC bindings, Kconfig ARCH_BST, base DTS, defconfig ARCH_BST) has already
> been merged into Linux 6.19 through the SoC tree [3].
>
> == Series Overview ==
>
> Patch 1: dt-bindings: mmc: add binding for BST DWCMSHC SDHCI controller
> Patch 2: mmc: sdhci: allow drivers to pre-allocate bounce buffer
> Patch 3: mmc: sdhci: add Black Sesame Technologies BST C1200 controller driver
> Patch 4: arm64: dts: bst: enable eMMC controller in C1200 CDCU1.0 board
> Patch 5: arm64: defconfig: enable BST SDHCI controller
> Patch 6: MAINTAINERS: add MMC files to BST entry
>
> == Testing ==
>
>   - checkpatch.pl: PASS (all patches)
>   - dt_binding_check: PASS
>   - dtbs_check (CHECK_DTBS=y): PASS
>   - Build tested with ARCH=arm64 defconfig
>
> == Changes since v4 ==
>
>   - Split: Platform patches merged separately via SoC tree; this series is
>     MMC-only, submitted to MMC maintainers
>
>   DT binding (patch 1):
>   - Rename file from bst,dwcmshc-sdhci.yaml to bst,c1200-sdhci.yaml
>   - Fix example compatible string to match property definition
>
>   Driver (patch 3):
>   - Fix compatible string to match dt-bindings (bst,c1200-sdhci)
>   - Simplify clock divider calculation with clearer frequency range logic
>   - Add linux/bits.h and linux/bitfield.h headers
>   - Remove unused linux/ioport.h header
>   - Rename SDHCI_TUNING_COUNT to BST_TUNING_COUNT
>   - Rename BST_EMMC_CTRL_BIT2 to BST_EMMC_CTRL_RST_N
>   - Fix BST_DEFAULT_MAX_FREQ from 2MHz to 200MHz
>   - Convert kernel-doc to regular comments (per Adrian Hunter)
>   - Add sdhci_bst_free_bounce_buffer() helper (per Adrian Hunter)
>
>
> == References ==
>
> [1] v4: https://lore.kernel.org/lkml/20250923-v4-patch-final-v1-0-2283ad7cbf88@thundersoft.com/
> [2] Split: https://lore.kernel.org/lkml/09b1318e-21dc-4354-8733-866b70696295@app.fastmail.com/
> [3] Merged via soc-newsoc-6.19
>
> Albert Yang (6):
>   dt-bindings: mmc: add binding for BST DWCMSHC SDHCI controller
>   mmc: sdhci: allow drivers to pre-allocate bounce buffer
>   mmc: sdhci: add Black Sesame Technologies BST C1200 controller driver
>   arm64: dts: bst: enable eMMC controller in C1200 CDCU1.0 board
>   arm64: defconfig: enable BST SDHCI controller
>   MAINTAINERS: add MMC files to BST entry
>
>  .../bindings/mmc/bst,c1200-sdhci.yaml         |  70 +++
>  MAINTAINERS                                   |   2 +
>  .../dts/bst/bstc1200-cdcu1.0-adas_4c2g.dts    |  19 +
>  arch/arm64/boot/dts/bst/bstc1200.dtsi         |  18 +
>  arch/arm64/configs/defconfig                  |   1 +
>  drivers/mmc/host/Kconfig                      |  14 +
>  drivers/mmc/host/Makefile                     |   1 +
>  drivers/mmc/host/sdhci-of-bst.c               | 521 ++++++++++++++++++
>  drivers/mmc/host/sdhci.c                      |   7 +
>  9 files changed, 653 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mmc/bst,c1200-sdhci.yaml
>  create mode 100644 drivers/mmc/host/sdhci-of-bst.c
>
> base-commit: 0f61b1860cc3f52aef9036d7235ed1f017632193
> --
> 2.43.0
>

Patch 1 to 3 and patch 6 applied for next, thanks!

The DTS patches (patch 4 and patch 5) should be picked up by the SoC maintainer.

Kind regards
Uffe