[PATCH v4] dmaengine: dw-edma: fix MSI data programming for multi-IRQ case

Shi-Shenghui posted 1 patch 4 days, 21 hours ago
There is a newer version of this series
drivers/dma/dw-edma/dw-edma-core.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
[PATCH v4] dmaengine: dw-edma: fix MSI data programming for multi-IRQ case
Posted by Shi-Shenghui 4 days, 21 hours ago
From: Shenghui Shi <brody.shi@m2semi.com>

When using MSI (not MSI-X) with multiple IRQs, the MSI data value
must be unique per vector to ensure correct interrupt delivery.
Currently, the driver fails to increment the MSI data per vector,
causing interrupts to be misrouted.

Fix this by caching the base MSI data and adjusting each vector's
data accordingly during IRQ setup.

Fixes: e63d79d1ff04 ("dmaengine: dw-edma: Add Synopsys DesignWare eDMA IP core driver")

Signed-off-by: Shenghui Shi <brody.shi@m2semi.com>
---
 drivers/dma/dw-edma/dw-edma-core.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/dw-edma/dw-edma-core.c b/drivers/dma/dw-edma/dw-edma-core.c
index 8e5f7defa6b6..570127069ddd 100644
--- a/drivers/dma/dw-edma/dw-edma-core.c
+++ b/drivers/dma/dw-edma/dw-edma-core.c
@@ -844,6 +844,7 @@ static int dw_edma_irq_request(struct dw_edma *dw,
 {
 	struct dw_edma_chip *chip = dw->chip;
 	struct device *dev = dw->chip->dev;
+	struct msi_desc *msi_desc;
 	u32 wr_mask = 1;
 	u32 rd_mask = 1;
 	int i, err = 0;
@@ -895,9 +896,14 @@ static int dw_edma_irq_request(struct dw_edma *dw,
 					  &dw->irq[i]);
 			if (err)
 				goto err_irq_free;
-
-			if (irq_get_msi_desc(irq))
+			msi_desc = irq_get_msi_desc(irq);
+			if (msi_desc) {
+				bool is_msi;
 				get_cached_msi_msg(irq, &dw->irq[i].msi);
+				is_msi = msi_desc && !msi_desc->pci.msi_attrib.is_msix;
+				if (is_msi)
+					dw->irq[i].msi.data = dw->irq[0].msi.data + i;
+			}
 		}
 
 		dw->nr_irqs = i;
-- 
2.49.0.windows.1