spi/xilinx: Leave the IRQ always enabled.

Instead of enabling the IRQ and disabling it for every transaction.

Specially the small transactions (1,2 words) benefit from removing 3 bus
accesses.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 5 insertions, 14 deletions

diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c
index 1890af8f8636..d933207c212c 100644
--- a/drivers/spi/spi-xilinx.c
+++ b/drivers/spi/spi-xilinx.c
@@ -167,8 +167,11 @@ static void xspi_init_hw(struct xilinx_spi *xspi)
         /* Reset the SPI device */
         xspi->write_fn(XIPIF_V123B_RESET_MASK,
                 regs_base + XIPIF_V123B_RESETR_OFFSET);
-        /* Disable all the interrupts just in case */
-        xspi->write_fn(0, regs_base + XIPIF_V123B_IIER_OFFSET);
+        /* Enable the transmit empty interrupt, which we use to determine
+         * progress on the transmission.
+         */
+        xspi->write_fn(XSPI_INTR_TX_EMPTY,
+                        regs_base + XIPIF_V123B_IIER_OFFSET);
         /* Enable the global IPIF interrupt */
         xspi->write_fn(XIPIF_V123B_GINTR_ENABLE,
                 regs_base + XIPIF_V123B_DGIER_OFFSET);
@@ -237,7 +240,6 @@ static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi, int n_words)
 static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
 {
         struct xilinx_spi *xspi = spi_master_get_devdata(spi->master);
-        u32 ipif_ier;
 
         /* We get here with transmitter inhibited */
 
@@ -246,14 +248,6 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
         xspi->remaining_bytes = t->len;
         reinit_completion(&xspi->done);
 
-
-        /* Enable the transmit empty interrupt, which we use to determine
-         * progress on the transmission.
-         */
-        ipif_ier = xspi->read_fn(xspi->regs + XIPIF_V123B_IIER_OFFSET);
-        xspi->write_fn(ipif_ier | XSPI_INTR_TX_EMPTY,
-                xspi->regs + XIPIF_V123B_IIER_OFFSET);
-
         for (;;) {
                 u16 cr;
                 int n_words;
@@ -290,9 +284,6 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
                         break;
         }
 
-        /* Disable the transmit empty interrupt */
-        xspi->write_fn(ipif_ier, xspi->regs + XIPIF_V123B_IIER_OFFSET);
-
         return t->len - xspi->remaining_bytes;
 }