From 40b6435a62befe3e487b6ea0ff69a0206a907b0b Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Tue, 1 Mar 2022 10:35:43 +0000 Subject: [PATCH] spi: dw: Force set K210 fifo length to 31 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. Signed-off-by: Damien Le Moal Signed-off-by: Niklas Cassel Reviewed-by: Sean Anderson --- drivers/spi/designware_spi.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/spi/designware_spi.c b/drivers/spi/designware_spi.c index 9200efc..f9b19a5 100644 --- a/drivers/spi/designware_spi.c +++ b/drivers/spi/designware_spi.c @@ -194,6 +194,20 @@ static int dw_spi_apb_init(struct udevice *bus, struct dw_spi_priv *priv) return 0; } +static int dw_spi_apb_k210_init(struct udevice *bus, struct dw_spi_priv *priv) +{ + /* + * 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. + */ + priv->fifo_len = 31; + + return dw_spi_apb_init(bus, priv); +} + static int dw_spi_dwc_init(struct udevice *bus, struct dw_spi_priv *priv) { priv->max_xfer = 32; @@ -758,7 +772,7 @@ static const struct udevice_id dw_spi_ids[] = { */ { .compatible = "altr,socfpga-spi", .data = (ulong)dw_spi_apb_init }, { .compatible = "altr,socfpga-arria10-spi", .data = (ulong)dw_spi_apb_init }, - { .compatible = "canaan,k210-spi", .data = (ulong)dw_spi_apb_init }, + { .compatible = "canaan,k210-spi", .data = (ulong)dw_spi_apb_k210_init}, { .compatible = "canaan,k210-ssi", .data = (ulong)dw_spi_dwc_init }, { .compatible = "intel,stratix10-spi", .data = (ulong)dw_spi_apb_init }, { .compatible = "intel,agilex-spi", .data = (ulong)dw_spi_apb_init }, -- 2.7.4