From: Geert Uytterhoeven Date: Mon, 2 Jun 2014 13:38:17 +0000 (+0200) Subject: spi: rspi: Add DMA support for QSPI on R-Car Gen2 X-Git-Tag: firefly_0821_release~176^2~3735^2~2^4~2 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4f12b5e529e4ff274eb478ec1c2ef41358ed9577;p=firefly-linux-kernel-4.4.55.git spi: rspi: Add DMA support for QSPI on R-Car Gen2 Enable DMA support for QSPI on R-Car Gen2, for Single, Dual, and Quad SPI Transfers. Performance figures for reading from a QSPI FLASH driven at 24.375 MHz on r8a7791/koelsch: - Single: 1.1 Mbps PIO, 23 Mbps DMA - Dual : 12.7 Mbps PIO, 48 Mbps DMA - Quad : 13 Mbps PIO, 70 Mbps DMA Signed-off-by: Geert Uytterhoeven Signed-off-by: Mark Brown --- diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c index b7f8be81423b..bec81470dd9c 100644 --- a/drivers/spi/spi-rspi.c +++ b/drivers/spi/spi-rspi.c @@ -642,6 +642,9 @@ static int qspi_transfer_out_in(struct rspi_data *rspi, qspi_receive_init(rspi); + if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) + return rspi_dma_transfer(rspi, &xfer->tx_sg, &xfer->rx_sg); + ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len); if (ret < 0) return ret; @@ -656,6 +659,9 @@ static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer) { int ret; + if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) + return rspi_dma_transfer(rspi, &xfer->tx_sg, NULL); + ret = rspi_pio_transfer(rspi, xfer->tx_buf, NULL, xfer->len); if (ret < 0) return ret; @@ -668,6 +674,9 @@ static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer) static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer) { + if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) + return rspi_dma_transfer(rspi, NULL, &xfer->rx_sg); + return rspi_pio_transfer(rspi, NULL, xfer->rx_buf, xfer->len); }