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spi: Using Trigger number to transmit/receive data

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In order to transmit and receive data when have 32 bytes of data that
ready has prepared on Transmit/Receive Buffer to transmit or receive.
Instead transmits/receives a byte data using Transmit/Receive Buffer
Data Triggering Number will improve the speed of transfer data.

Signed-off-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Hiep Cao Minh 2014-10-23 12:14:13 +09:00 committed by Mark Brown
parent c517d838eb
commit 4b6fe3edcb
1 changed files with 118 additions and 8 deletions
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126
drivers/spi/spi-rspi.c
View file

@ -177,6 +177,13 @@
#define SPBFCR_RXRST 0x40 /* Receive Buffer Data Reset */
#define SPBFCR_TXTRG_MASK 0x30 /* Transmit Buffer Data Triggering Number */
#define SPBFCR_RXTRG_MASK 0x07 /* Receive Buffer Data Triggering Number */
/* QSPI on R-Car Gen2 */
#define SPBFCR_TXTRG_1B 0x00 /* 31 bytes (1 byte available) */
#define SPBFCR_TXTRG_32B 0x30 /* 0 byte (32 bytes available) */
#define SPBFCR_RXTRG_1B 0x00 /* 1 byte (31 bytes available) */
#define SPBFCR_RXTRG_32B 0x07 /* 32 bytes (0 byte available) */
#define QSPI_BUFFER_SIZE 32u
struct rspi_data {
void __iomem *addr;
@ -366,6 +373,52 @@ static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
return 0;
}
static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
{
u8 data;
data = rspi_read8(rspi, reg);
data &= ~mask;
data |= (val & mask);
rspi_write8(rspi, data, reg);
}
static int qspi_set_send_trigger(struct rspi_data *rspi, unsigned int len)
{
unsigned int n;
n = min(len, QSPI_BUFFER_SIZE);
if (len >= QSPI_BUFFER_SIZE) {
/* sets triggering number to 32 bytes */
qspi_update(rspi, SPBFCR_TXTRG_MASK,
SPBFCR_TXTRG_32B, QSPI_SPBFCR);
} else {
/* sets triggering number to 1 byte */
qspi_update(rspi, SPBFCR_TXTRG_MASK,
SPBFCR_TXTRG_1B, QSPI_SPBFCR);
}
return n;
}
static void qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
{
unsigned int n;
n = min(len, QSPI_BUFFER_SIZE);
if (len >= QSPI_BUFFER_SIZE) {
/* sets triggering number to 32 bytes */
qspi_update(rspi, SPBFCR_RXTRG_MASK,
SPBFCR_RXTRG_32B, QSPI_SPBFCR);
} else {
/* sets triggering number to 1 byte */
qspi_update(rspi, SPBFCR_RXTRG_MASK,
SPBFCR_RXTRG_1B, QSPI_SPBFCR);
}
}
#define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
@ -609,18 +662,28 @@ static bool rspi_can_dma(struct spi_master *master, struct spi_device *spi,
return __rspi_can_dma(rspi, xfer);
}
static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
struct spi_transfer *xfer)
{
if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
int ret = rspi_dma_transfer(rspi, &xfer->tx_sg,
xfer->rx_buf ? &xfer->rx_sg : NULL);
if (ret != -EAGAIN)
return 0;
}
return -EAGAIN;
}
static int rspi_common_transfer(struct rspi_data *rspi,
struct spi_transfer *xfer)
{
int ret;
if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
ret = rspi_dma_transfer(rspi, &xfer->tx_sg,
xfer->rx_buf ? &xfer->rx_sg : NULL);
if (ret != -EAGAIN)
return ret;
}
ret = rspi_dma_check_then_transfer(rspi, xfer);
if (ret != -EAGAIN)
return ret;
ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
if (ret < 0)
@ -661,12 +724,59 @@ static int rspi_rz_transfer_one(struct spi_master *master,
return rspi_common_transfer(rspi, xfer);
}
static int qspi_trigger_transfer_out_int(struct rspi_data *rspi, const u8 *tx,
u8 *rx, unsigned int len)
{
unsigned int i, n, ret;
int error;
while (len > 0) {
n = qspi_set_send_trigger(rspi, len);
qspi_set_receive_trigger(rspi, len);
if (n == QSPI_BUFFER_SIZE) {
error = rspi_wait_for_tx_empty(rspi);
if (error < 0) {
dev_err(&rspi->master->dev, "transmit timeout\n");
return error;
}
for (i = 0; i < n; i++)
rspi_write_data(rspi, *tx++);
error = rspi_wait_for_rx_full(rspi);
if (error < 0) {
dev_err(&rspi->master->dev, "receive timeout\n");
return error;
}
for (i = 0; i < n; i++)
*rx++ = rspi_read_data(rspi);
} else {
ret = rspi_pio_transfer(rspi, tx, rx, n);
if (ret < 0)
return ret;
}
len -= n;
}
return 0;
}
static int qspi_transfer_out_in(struct rspi_data *rspi,
struct spi_transfer *xfer)
{
int ret;
qspi_receive_init(rspi);
return rspi_common_transfer(rspi, xfer);
ret = rspi_dma_check_then_transfer(rspi, xfer);
if (ret != -EAGAIN)
return ret;
ret = qspi_trigger_transfer_out_int(rspi, xfer->tx_buf,
xfer->rx_buf, xfer->len);
if (ret < 0)
return ret;
return 0;
}
static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)