spi: rspi: supports 32bytes buffer for DUAL and QUAD

This patch supports 32bytes of buffer for DUAL and QUAD in QSPI by
Using Transmit/Receive Buffer Data Triggering Number.
In order to improve the DUAL and QUAD's performance of SPI
while transferring data in PIO mode, it sends/receives each 32bytes
data instead of each byte data as current situation.

Signed-off-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index a816f07e168e84b0192224dcaadb99cb377ac9ed..3bab75ab1b257e5f2359bad0ecb92bbf7c55c137 100644 (file)
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -413,7 +413,7 @@ static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
        return n;
 }
 
-static void qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
+static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
 {
        unsigned int n;
 
@@ -428,6 +428,7 @@ static void qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
                qspi_update(rspi, SPBFCR_RXTRG_MASK,
                             SPBFCR_RXTRG_1B, QSPI_SPBFCR);
        }
+       return n;
 }
 
 #define set_config_register(spi, n) spi->ops->set_config_register(spi, n)
@@ -514,6 +515,51 @@ static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
        return 0;
 }
 
+static int rspi_pio_transfer_in_or_our(struct rspi_data *rspi, const u8 *tx,
+                                      u8 *rx, unsigned int n)
+{
+       unsigned int i, len;
+       int ret;
+
+       while (n > 0) {
+               if (tx) {
+                       len = qspi_set_send_trigger(rspi, n);
+                       if (len == QSPI_BUFFER_SIZE) {
+                               ret = rspi_wait_for_tx_empty(rspi);
+                               if (ret < 0) {
+                                       dev_err(&rspi->master->dev, "transmit timeout\n");
+                                       return ret;
+                               }
+                               for (i = 0; i < len; i++)
+                                       rspi_write_data(rspi, *tx++);
+                       } else {
+                               ret = rspi_pio_transfer(rspi, tx, NULL, n);
+                               if (ret < 0)
+                                       return ret;
+                       }
+               }
+               if (rx) {
+                       len = qspi_set_receive_trigger(rspi, n);
+                       if (len == QSPI_BUFFER_SIZE) {
+                               ret = rspi_wait_for_rx_full(rspi);
+                               if (ret < 0) {
+                                       dev_err(&rspi->master->dev, "receive timeout\n");
+                                       return ret;
+                               }
+                               for (i = 0; i < len; i++)
+                                       *rx++ = rspi_read_data(rspi);
+                       } else {
+                               ret = rspi_pio_transfer(rspi, NULL, rx, n);
+                               if (ret < 0)
+                                       return ret;
+                               *rx++ = ret;
+                       }
+               }
+               n -= len;
+       }
+       return 0;
+}
+
 static void rspi_dma_complete(void *arg)
 {
        struct rspi_data *rspi = arg;
@@ -793,7 +839,7 @@ static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
                        return ret;
        }
 
-       ret = rspi_pio_transfer(rspi, xfer->tx_buf, NULL, xfer->len);
+       ret = rspi_pio_transfer_in_or_our(rspi, xfer->tx_buf, NULL, xfer->len);
        if (ret < 0)
                return ret;
 
@@ -811,7 +857,7 @@ static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
                        return ret;
        }
 
-       return rspi_pio_transfer(rspi, NULL, xfer->rx_buf, xfer->len);
+       return rspi_pio_transfer_in_or_our(rspi, NULL, xfer->rx_buf, xfer->len);
 }
 
 static int qspi_transfer_one(struct spi_master *master, struct spi_device *spi,