diff options
| author | Jon Lin <jon.lin@rock-chips.com> | 2020-07-23 08:43:54 +0800 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2020-07-28 17:29:30 +0100 |
| commit | 4d9ca632c847ab88f2f7e7e2747aea966f1390ce (patch) | |
| tree | d5249e31d7615dab7d0d77c6f27b35599611370a /drivers/spi/spi-rockchip.c | |
| parent | 15b413d93ccd0d26c29f005df82c299c8f14cbd6 (diff) | |
spi: rockchip: Config spi rx dma burst size depend on xfer length
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>
Tested-by: Emil Renner Berthing <kernel@esmil.dk>
Reviewed-by: Emil Renner Berthing <kernel@esmil.dk>
Link: https://lore.kernel.org/r/20200723004356.6390-1-jon.lin@rock-chips.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-rockchip.c')
| -rw-r--r-- | drivers/spi/spi-rockchip.c | 19 |
1 files 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 |