[PATCH] coresight: tmc: Configure DMA mask appropriately

From: Robin Murphy
Date: Thu May 18 2017 - 11:14:38 EST


Before making any DMA API calls, the ETR driver should really be setting
its masks to ensure that DMA is possible. Especially since it can
address more than the 32-bit default mask set by the AMBA bus code.

Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
---
drivers/hwtracing/coresight/coresight-tmc.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c
index d8517d2a968c..864488793f09 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc.c
@@ -362,6 +362,13 @@ static int tmc_probe(struct amba_device *adev, const struct amba_id *id)
desc.type = CORESIGHT_DEV_TYPE_SINK;
desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER;
desc.ops = &tmc_etr_cs_ops;
+ /*
+ * ETR configuration uses a 40-bit AXI master in place of
+ * the embedded SRAM of ETB/ETF.
+ */
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(40));
+ if (ret)
+ goto out;
} else {
desc.type = CORESIGHT_DEV_TYPE_LINKSINK;
desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_FIFO;
--
2.12.2.dirty