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.riba...@gmail.com>
---
drivers/spi/spi-xilinx.c | 19 +++++--------------
1 file changed, 5 insertions(+), 14 deletions(-)
diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c
index 17480a2..408a842 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;
}
--
2.1.4
--
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