[PATCH V2 08/12] serial: tegra: add support to use 8 bytes trigger

From: Krishna Yarlagadda
Date: Wed Sep 04 2019 - 00:43:51 EST


Add support to use 8 bytes trigger for Tegra186 SOC.

Signed-off-by: Shardar Shariff Md <smohammed@xxxxxxxxxx>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@xxxxxxxxxx>
---
drivers/tty/serial/serial-tegra.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index 8422516..02f8535 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -88,6 +88,7 @@ struct tegra_uart_chip_data {
bool support_clk_src_div;
bool fifo_mode_enable_status;
int uart_max_port;
+ int max_dma_burst_bytes;
};

struct tegra_uart_port {
@@ -931,7 +932,12 @@ static int tegra_uart_hw_init(struct tegra_uart_port *tup)
* programmed in the DMA registers.
*/
tup->fcr_shadow = UART_FCR_ENABLE_FIFO;
- tup->fcr_shadow |= UART_FCR_R_TRIG_01;
+
+ if (tup->cdata->max_dma_burst_bytes == 8)
+ tup->fcr_shadow |= UART_FCR_R_TRIG_10;
+ else
+ tup->fcr_shadow |= UART_FCR_R_TRIG_01;
+
tup->fcr_shadow |= TEGRA_UART_TX_TRIG_16B;
tegra_uart_write(tup, tup->fcr_shadow, UART_FCR);

@@ -1045,7 +1051,7 @@ static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup,
}
dma_sconfig.src_addr = tup->uport.mapbase;
dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
- dma_sconfig.src_maxburst = 4;
+ dma_sconfig.src_maxburst = tup->cdata->max_dma_burst_bytes;
tup->rx_dma_chan = dma_chan;
tup->rx_dma_buf_virt = dma_buf;
tup->rx_dma_buf_phys = dma_phys;
@@ -1324,6 +1330,7 @@ static struct tegra_uart_chip_data tegra20_uart_chip_data = {
.support_clk_src_div = false,
.fifo_mode_enable_status = false,
.uart_max_port = 5,
+ .max_dma_burst_bytes = 4,
};

static struct tegra_uart_chip_data tegra30_uart_chip_data = {
@@ -1332,6 +1339,7 @@ static struct tegra_uart_chip_data tegra30_uart_chip_data = {
.support_clk_src_div = true,
.fifo_mode_enable_status = false,
.uart_max_port = 5,
+ .max_dma_burst_bytes = 4,
};

static struct tegra_uart_chip_data tegra186_uart_chip_data = {
@@ -1340,6 +1348,7 @@ static struct tegra_uart_chip_data tegra186_uart_chip_data = {
.support_clk_src_div = true,
.fifo_mode_enable_status = true,
.uart_max_port = 8,
+ .max_dma_burst_bytes = 8,
};

static const struct of_device_id tegra_uart_of_match[] = {
--
2.7.4