[0/3] DW apb_ssi V4 support for Kendryte K210 RISC-V SoC

Message

Damien Le Moal Nov. 19, 2020, 12:02 p.m. UTC

The Canaan Kendryte K210 RISC-V SoC includes a DesignWare apb_ssi V4
SPI controller implemented with a maximum data frame size of 32-bits
(SSI_MAX_XFER_SIZE=32 synthesis parameter).

This series of patches adds support for this SoC by adding implementing
changes necessary to support the 32-bits xfer size configuration. This
is done in patch 1.

Patch 2 introduces a workaround for a HW bug on this SoC which triggers
RX FIFO overrun errors when the RX FIFO fills up to its maximum detected
depth of 32. The patch manually reduces the fifo depth to 31.

Patch 3 documents the new compatible string "canaan,k210-spi" used to
identify this SoC.

Damien Le Moal (3):
  spi: dw: Add support for 32-bits max xfer size
  spi: dw: Add support for the Canaan K210 SoC SPI
  dt-bindings: Update Synopsis DW apb ssi bindings

 .../bindings/spi/snps,dw-apb-ssi.yaml         |  2 +
 drivers/spi/spi-dw-core.c                     | 40 +++++++++++++++----
 drivers/spi/spi-dw-mmio.c                     | 16 ++++++++
 drivers/spi/spi-dw.h                          |  8 ++++
 4 files changed, 59 insertions(+), 7 deletions(-)