diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c index 189b517f77fc..1cf9e3ffe07b 100644 --- a/drivers/spi/spi-dw-mid.c +++ b/drivers/spi/spi-dw-mid.c @@ -36,6 +36,31 @@ static bool mid_spi_dma_chan_filter(struct dma_chan *chan, void *param) return true; } +static void mid_spi_maxburst_init(struct dw_spi *dws) +{ + struct dma_slave_caps caps; + u32 max_burst, def_burst; + int ret; + + def_burst = dws->fifo_len / 2; + + ret = dma_get_slave_caps(dws->rxchan, &caps); + if (!ret && caps.max_burst) + max_burst = caps.max_burst; + else + max_burst = RX_BURST_LEVEL; + + dws->rxburst = min(max_burst, def_burst); + + ret = dma_get_slave_caps(dws->txchan, &caps); + if (!ret && caps.max_burst) + max_burst = caps.max_burst; + else + max_burst = TX_BURST_LEVEL; + + dws->txburst = min(max_burst, def_burst); +} + static int mid_spi_dma_init_mfld(struct device *dev, struct dw_spi *dws) { struct dw_dma_slave slave = { @@ -73,6 +98,8 @@ static int mid_spi_dma_init_mfld(struct device *dev, struct dw_spi *dws) init_completion(&dws->dma_completion); + mid_spi_maxburst_init(dws); + return 0; free_rxchan: @@ -100,6 +127,8 @@ static int mid_spi_dma_init_generic(struct device *dev, struct dw_spi *dws) init_completion(&dws->dma_completion); + mid_spi_maxburst_init(dws); + return 0; } @@ -229,7 +258,7 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws, memset(&txconf, 0, sizeof(txconf)); txconf.direction = DMA_MEM_TO_DEV; txconf.dst_addr = dws->dma_addr; - txconf.dst_maxburst = TX_BURST_LEVEL; + txconf.dst_maxburst = dws->txburst; txconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; txconf.dst_addr_width = convert_dma_width(dws->n_bytes); txconf.device_fc = false; @@ -321,7 +350,7 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws, memset(&rxconf, 0, sizeof(rxconf)); rxconf.direction = DMA_DEV_TO_MEM; rxconf.src_addr = dws->dma_addr; - rxconf.src_maxburst = RX_BURST_LEVEL; + rxconf.src_maxburst = dws->rxburst; rxconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; rxconf.src_addr_width = convert_dma_width(dws->n_bytes); rxconf.device_fc = false; @@ -346,8 +375,8 @@ static int mid_spi_dma_setup(struct dw_spi *dws, struct spi_transfer *xfer) { u16 imr = 0, dma_ctrl = 0; - dw_writel(dws, DW_SPI_DMARDLR, RX_BURST_LEVEL - 1); - dw_writel(dws, DW_SPI_DMATDLR, TX_BURST_LEVEL); + dw_writel(dws, DW_SPI_DMARDLR, dws->rxburst - 1); + dw_writel(dws, DW_SPI_DMATDLR, dws->fifo_len - dws->txburst); if (xfer->tx_buf) { dma_ctrl |= SPI_DMA_TDMAE; diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h index 9585d0c83a6d..9247670fcdfb 100644 --- a/drivers/spi/spi-dw.h +++ b/drivers/spi/spi-dw.h @@ -142,7 +142,9 @@ struct dw_spi { /* DMA info */ struct dma_chan *txchan; + u32 txburst; struct dma_chan *rxchan; + u32 rxburst; unsigned long dma_chan_busy; dma_addr_t dma_addr; /* phy address of the Data register */ const struct dw_spi_dma_ops *dma_ops;