diff options
| author | Damien Le Moal <damien.lemoal@wdc.com> | 2020-12-06 10:18:17 +0900 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2020-12-09 12:14:23 +0000 |
| commit | b0dfd948379c79b8754e224e29b99d30ce0d79b8 (patch) | |
| tree | 7b05c3ef22cf6a5edabb20b173ee26a90a53b388 /drivers/spi | |
| parent | a51acc2400d47df0f87e1f011c63266421c594b9 (diff) | |
spi: dw: Add support for the Canaan K210 SoC SPI
The Canaan Kendryte K210 RISC-V SoC includes a DW apb_ssi v4 controller
which is documented to have a 32 words deep TX and RX FIFO. The FIFO
length detection in spi_hw_init() correctly detects this value.
However, when the controller RX FIFO is filled up to 32 entries
(RXFLR = 32), an RX FIFO overrun error occurs. This likely due to a
hardware bug which can be avoided by force setting the fifo_len field of
struct dw_spi to 31.
Define the dw_spi_canaan_k210_init() function to force set fifo_len to
31 when the device node compatible string is "canaan,k210-spi".
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20201206011817.11700-4-damien.lemoal@wdc.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-dw-mmio.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c index d0cc5bf4fa4e..17c06039a74d 100644 --- a/drivers/spi/spi-dw-mmio.c +++ b/drivers/spi/spi-dw-mmio.c @@ -222,6 +222,21 @@ static int dw_spi_keembay_init(struct platform_device *pdev, return 0; } +static int dw_spi_canaan_k210_init(struct platform_device *pdev, + struct dw_spi_mmio *dwsmmio) +{ + /* + * The Canaan Kendryte K210 SoC DW apb_ssi v4 spi controller is + * documented to have a 32 word deep TX and RX FIFO, which + * spi_hw_init() detects. However, when the RX FIFO is filled up to + * 32 entries (RXFLR = 32), an RX FIFO overrun error occurs. Avoid this + * problem by force setting fifo_len to 31. + */ + dwsmmio->dws.fifo_len = 31; + + return 0; +} + static int dw_spi_mmio_probe(struct platform_device *pdev) { int (*init_func)(struct platform_device *pdev, @@ -335,6 +350,7 @@ static const struct of_device_id dw_spi_mmio_of_match[] = { { .compatible = "snps,dwc-ssi-1.01a", .data = dw_spi_dwc_ssi_init}, { .compatible = "intel,keembay-ssi", .data = dw_spi_keembay_init}, { .compatible = "microchip,sparx5-spi", dw_spi_mscc_sparx5_init}, + { .compatible = "canaan,k210-spi", dw_spi_canaan_k210_init}, { /* end of table */} }; MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match); |