[PATCH v1 1/3] spi: rockchip: Config spi rx dma burst size depend on xfer length

[PATCH v1 1/3] spi: rockchip: Config spi rx dma burst size depend on xfer length

[Jon Lin]

The burst length can be adjusted according to the transmission
length to improve the transmission rate

Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
---
 drivers/spi/spi-rockchip.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 9b8a5e1233c0..63593a5b87fa 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -384,6 +384,19 @@ static void rockchip_spi_dma_txcb(void *data)
 	spi_finalize_current_transfer(ctlr);
 }
 
+static u32 rockchip_spi_calc_burst_size(u32 data_len)
+{
+	u32 i;
+
+	/* burst size: 1, 2, 4, 8 */
+	for (i = 1; i < 8; i <<= 1) {
+		if (data_len & i)
+			break;
+	}
+
+	return i;
+}
+
 static int rockchip_spi_prepare_dma(struct rockchip_spi *rs,
 		struct spi_controller *ctlr, struct spi_transfer *xfer)
 {
@@ -397,7 +410,8 @@ static int rockchip_spi_prepare_dma(struct rockchip_spi *rs,
 			.direction = DMA_DEV_TO_MEM,
 			.src_addr = rs->dma_addr_rx,
 			.src_addr_width = rs->n_bytes,
-			.src_maxburst = 1,
+			.src_maxburst = rockchip_spi_calc_burst_size(xfer->len /
+								     rs->n_bytes),
 		};
 
 		dmaengine_slave_config(ctlr->dma_rx, &rxconf);
@@ -525,7 +539,8 @@ static void rockchip_spi_config(struct rockchip_spi *rs,
 		writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
 
 	writel_relaxed(rs->fifo_len / 2, rs->regs + ROCKCHIP_SPI_DMATDLR);
-	writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR);
+	writel_relaxed(rockchip_spi_calc_burst_size(xfer->len / rs->n_bytes) - 1,
+		       rs->regs + ROCKCHIP_SPI_DMARDLR);
 	writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR);
 
 	/* the hardware only supports an even clock divisor, so
-- 
2.17.1

[PATCH v1 2/3] spi: rockchip: Support 64-location deep FIFOs

[Jon Lin]

The FIFO depth of SPI V2 is 64 instead of 32, add support for it.

Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
---
 drivers/spi/spi-rockchip.c | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 63593a5b87fa..a451dacab5cf 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -39,8 +39,9 @@
 #define ROCKCHIP_SPI_RISR			0x0034
 #define ROCKCHIP_SPI_ICR			0x0038
 #define ROCKCHIP_SPI_DMACR			0x003c
-#define ROCKCHIP_SPI_DMATDLR		0x0040
-#define ROCKCHIP_SPI_DMARDLR		0x0044
+#define ROCKCHIP_SPI_DMATDLR			0x0040
+#define ROCKCHIP_SPI_DMARDLR			0x0044
+#define ROCKCHIP_SPI_VERSION			0x0048
 #define ROCKCHIP_SPI_TXDR			0x0400
 #define ROCKCHIP_SPI_RXDR			0x0800
 
@@ -156,6 +157,8 @@
 #define ROCKCHIP_SPI_MAX_TRANLEN		0xffff
 
 #define ROCKCHIP_SPI_MAX_CS_NUM			2
+#define ROCKCHIP_SPI_VER2_TYPE1			0x05EC0002
+#define ROCKCHIP_SPI_VER2_TYPE2			0x00110002
 
 struct rockchip_spi {
 	struct device *dev;
@@ -206,17 +209,17 @@ static inline void wait_for_idle(struct rockchip_spi *rs)
 
 static u32 get_fifo_len(struct rockchip_spi *rs)
 {
-	u32 fifo;
+	u32 ver;
 
-	for (fifo = 2; fifo < 32; fifo++) {
-		writel_relaxed(fifo, rs->regs + ROCKCHIP_SPI_TXFTLR);
-		if (fifo != readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFTLR))
-			break;
-	}
-
-	writel_relaxed(0, rs->regs + ROCKCHIP_SPI_TXFTLR);
+	ver = readl_relaxed(rs->regs + ROCKCHIP_SPI_VERSION);
 
-	return (fifo == 31) ? 0 : fifo;
+	switch (ver) {
+	case ROCKCHIP_SPI_VER2_TYPE1:
+	case ROCKCHIP_SPI_VER2_TYPE2:
+		return 64;
+	default:
+		return 32;
+	}
 }
 
 static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
-- 
2.17.1

[PATCH v1 3/3] spi: rockchip: Fix error in SPI slave pio read

[Jon Lin]

The RXFLR is possible larger than rx_left in Rockchip SPI, fix it.

Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
---
 drivers/spi/spi-rockchip.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index a451dacab5cf..1f5e613b67d9 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -291,7 +291,7 @@ static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
 static void rockchip_spi_pio_reader(struct rockchip_spi *rs)
 {
 	u32 words = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR);
-	u32 rx_left = rs->rx_left - words;
+	u32 rx_left = rs->rx_left > words ? rs->rx_left - words : 0;
 
 	/* the hardware doesn't allow us to change fifo threshold
 	 * level while spi is enabled, so instead make sure to leave
-- 
2.17.1

Re: [PATCH v1 3/3] spi: rockchip: Fix error in SPI slave pio read

[Heiko Stübner]

Hi Jon,

Am Mittwoch, 22. Juli 2020, 08:52:57 CEST schrieb Jon Lin:
> The RXFLR is possible larger than rx_left in Rockchip SPI, fix it.
> 
> Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
> ---
>  drivers/spi/spi-rockchip.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
> index a451dacab5cf..1f5e613b67d9 100644
> --- a/drivers/spi/spi-rockchip.c
> +++ b/drivers/spi/spi-rockchip.c
> @@ -291,7 +291,7 @@ static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
>  static void rockchip_spi_pio_reader(struct rockchip_spi *rs)
>  {
>  	u32 words = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR);
> -	u32 rx_left = rs->rx_left - words;
> +	u32 rx_left = rs->rx_left > words ? rs->rx_left - words : 0;

I guess for future readability of the code braces might be nice, like

	u32 rx_left = (rs->rx_left > words) ? rs->rx_left - words : 0;

But I stumbled onto (and fixed similarly) that issue yesterday as well, so

Reviewed-by: Heiko Stuebner <heiko@sntech.de>


Heiko