From: Huibin Hong Date: Wed, 10 Oct 2018 09:00:33 +0000 (+0200) Subject: spi: rockchip: adjust dma watermark and burstlen X-Git-Tag: v4.20-rc5~38^2~27 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=dcfc861d24ec19f0d0d3d55bb016646794571fbb;p=linux.git spi: rockchip: adjust dma watermark and burstlen Signal tx dma when spi fifo is less than half full, and limit tx bursts to half the fifo length. Clamp rx burst length to 1 to avoid alignment issues. Signed-off-by: Huibin Hong Signed-off-by: Emil Renner Berthing Signed-off-by: Mark Brown --- diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index fdcf3076681b..2f825702cd90 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -455,10 +455,7 @@ static int rockchip_spi_prepare_dma(struct rockchip_spi *rs) rxconf.direction = rs->dma_rx.direction; rxconf.src_addr = rs->dma_rx.addr; rxconf.src_addr_width = rs->n_bytes; - if (rs->dma_caps.max_burst > 4) - rxconf.src_maxburst = 4; - else - rxconf.src_maxburst = 1; + rxconf.src_maxburst = 1; dmaengine_slave_config(rs->dma_rx.ch, &rxconf); rxdesc = dmaengine_prep_slave_sg( @@ -477,10 +474,7 @@ static int rockchip_spi_prepare_dma(struct rockchip_spi *rs) txconf.direction = rs->dma_tx.direction; txconf.dst_addr = rs->dma_tx.addr; txconf.dst_addr_width = rs->n_bytes; - if (rs->dma_caps.max_burst > 4) - txconf.dst_maxburst = 4; - else - txconf.dst_maxburst = 1; + txconf.dst_maxburst = rs->fifo_len / 2; dmaengine_slave_config(rs->dma_tx.ch, &txconf); txdesc = dmaengine_prep_slave_sg( @@ -578,7 +572,7 @@ static void rockchip_spi_config(struct rockchip_spi *rs) writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_TXFTLR); writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR); - writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMATDLR); + writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_DMATDLR); writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR); writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR);