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authorSowjanya Komatineni <skomatineni@nvidia.com>2019-03-26 22:56:29 -0700
committerMark Brown <broonie@kernel.org>2019-04-01 15:39:42 +0700
commitf4ce428c41fb22e3ed55496dded94df44cb920fa (patch)
tree7a792e6e31c95ca8d9acd3512a2e31d7256feba7 /drivers/spi/spi-tegra114.c
parentc4fc9e5b28ff787e35137c2cc13316bb11d7657b (diff)
spi: tegra114: configure dma burst size to fifo trig level
Fixes: Configure DMA burst size to be same as SPI TX/RX trigger levels to avoid mismatch. SPI FIFO trigger levels are calculated based on the transfer length. So this patch moves DMA slave configuration to happen before start of DMAs. Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-tegra114.c')
-rw-r--r--drivers/spi/spi-tegra114.c52
1 files changed, 30 insertions, 22 deletions
diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c
index 28aa080a94ff..05bb2f9bff3c 100644
--- a/drivers/spi/spi-tegra114.c
+++ b/drivers/spi/spi-tegra114.c
@@ -529,6 +529,8 @@ static int tegra_spi_start_dma_based_transfer(
u32 val;
unsigned int len;
int ret = 0;
+ u8 dma_burst;
+ struct dma_slave_config dma_sconfig = {0};
val = SPI_DMA_BLK_SET(tspi->curr_dma_words - 1);
tegra_spi_writel(tspi, val, SPI_DMA_BLK);
@@ -540,12 +542,16 @@ static int tegra_spi_start_dma_based_transfer(
len = tspi->curr_dma_words * 4;
/* Set attention level based on length of transfer */
- if (len & 0xF)
+ if (len & 0xF) {
val |= SPI_TX_TRIG_1 | SPI_RX_TRIG_1;
- else if (((len) >> 4) & 0x1)
+ dma_burst = 1;
+ } else if (((len) >> 4) & 0x1) {
val |= SPI_TX_TRIG_4 | SPI_RX_TRIG_4;
- else
+ dma_burst = 4;
+ } else {
val |= SPI_TX_TRIG_8 | SPI_RX_TRIG_8;
+ dma_burst = 8;
+ }
if (tspi->cur_direction & DATA_DIR_TX)
val |= SPI_IE_TX;
@@ -556,7 +562,18 @@ static int tegra_spi_start_dma_based_transfer(
tegra_spi_writel(tspi, val, SPI_DMA_CTL);
tspi->dma_control_reg = val;
+ dma_sconfig.device_fc = true;
if (tspi->cur_direction & DATA_DIR_TX) {
+ dma_sconfig.dst_addr = tspi->phys + SPI_TX_FIFO;
+ dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dma_sconfig.dst_maxburst = dma_burst;
+ ret = dmaengine_slave_config(tspi->tx_dma_chan, &dma_sconfig);
+ if (ret < 0) {
+ dev_err(tspi->dev,
+ "DMA slave config failed: %d\n", ret);
+ return ret;
+ }
+
tegra_spi_copy_client_txbuf_to_spi_txbuf(tspi, t);
ret = tegra_spi_start_tx_dma(tspi, len);
if (ret < 0) {
@@ -567,6 +584,16 @@ static int tegra_spi_start_dma_based_transfer(
}
if (tspi->cur_direction & DATA_DIR_RX) {
+ dma_sconfig.src_addr = tspi->phys + SPI_RX_FIFO;
+ dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dma_sconfig.src_maxburst = dma_burst;
+ ret = dmaengine_slave_config(tspi->rx_dma_chan, &dma_sconfig);
+ if (ret < 0) {
+ dev_err(tspi->dev,
+ "DMA slave config failed: %d\n", ret);
+ return ret;
+ }
+
/* Make the dma buffer to read by dma */
dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys,
tspi->dma_buf_size, DMA_FROM_DEVICE);
@@ -626,7 +653,6 @@ static int tegra_spi_init_dma_param(struct tegra_spi_data *tspi,
u32 *dma_buf;
dma_addr_t dma_phys;
int ret;
- struct dma_slave_config dma_sconfig;
dma_chan = dma_request_slave_channel_reason(tspi->dev,
dma_to_memory ? "rx" : "tx");
@@ -647,19 +673,6 @@ static int tegra_spi_init_dma_param(struct tegra_spi_data *tspi,
}
if (dma_to_memory) {
- dma_sconfig.src_addr = tspi->phys + SPI_RX_FIFO;
- dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
- dma_sconfig.src_maxburst = 0;
- } else {
- dma_sconfig.dst_addr = tspi->phys + SPI_TX_FIFO;
- dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
- dma_sconfig.dst_maxburst = 0;
- }
-
- ret = dmaengine_slave_config(dma_chan, &dma_sconfig);
- if (ret)
- goto scrub;
- if (dma_to_memory) {
tspi->rx_dma_chan = dma_chan;
tspi->rx_dma_buf = dma_buf;
tspi->rx_dma_phys = dma_phys;
@@ -669,11 +682,6 @@ static int tegra_spi_init_dma_param(struct tegra_spi_data *tspi,
tspi->tx_dma_phys = dma_phys;
}
return 0;
-
-scrub:
- dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys);
- dma_release_channel(dma_chan);
- return ret;
}
static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi,