spi: spi-loopback-test: Add test to trigger DMA/PIO mixing

Add a test where a small and a large transfer in a message hit the same
cache line.  This test currently fails on spi-s3c64xx on in DMA mode
since it ends up mixing DMA and PIO without proper cache maintenance.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Link: https://lore.kernel.org/r/20220916113951.228398-2-vincent.whitchurch@axis.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-loopback-test.c b/drivers/spi/spi-loopback-test.c
index 4d4f77a..dd7de8f 100644 (file)
--- a/drivers/spi/spi-loopback-test.c
+++ b/drivers/spi/spi-loopback-test.c
@@ -313,6 +313,33 @@ static struct spi_test spi_tests[] = {
                        },
                },
        },
+       {
+               .description    = "three tx+rx transfers with overlapping cache lines",
+               .fill_option    = FILL_COUNT_8,
+               /*
+                * This should be large enough for the controller driver to
+                * choose to transfer it with DMA.
+                */
+               .iterate_len    = { 512, -1 },
+               .iterate_transfer_mask = BIT(1),
+               .transfer_count = 3,
+               .transfers              = {
+                       {
+                               .len = 1,
+                               .tx_buf = TX(0),
+                               .rx_buf = RX(0),
+                       },
+                       {
+                               .tx_buf = TX(1),
+                               .rx_buf = RX(1),
+                       },
+                       {
+                               .len = 1,
+                               .tx_buf = TX(513),
+                               .rx_buf = RX(513),
+                       },
+               },
+       },
 
        { /* end of tests sequence */ }
 };