On 2021-01-27 19:07, Rob Herring wrote:
On Tue, Jan 19, 2021 at 4:52 AM Yong Wu <yong.wu@xxxxxxxxxxxx> wrote:
The commit e0d072782c73 ("dma-mapping: introduce DMA range map,
supplanting dma_pfn_offset") always update dma_range_map even though it was
already set, like in the sunxi_mbus driver. the issue is reported at [1].
This patch avoid this(Updating it only when dev has valid dma-ranges).
only when dev *doesn't* have valid dma-ranges?
I believe the intent is to mean when a valid "dma-ranges" property is
specified in DT. The implementation allows DT to take precedence even if
platform code *has* already installed a dma_range_map, although we
shouldn't expect that to ever happen (except perhaps in the wild early
days of platform bringup).
Robin.
Meanwhile, dma_range_map contains the devices' dma_ranges information,
This patch moves dma_range_map before of_iommu_configure. The iommu
driver may need to know the dma_address requirements of its iommu
consumer devices.
[1] https://lore.kernel.org/linux-arm-kernel/5c7946f3-b56e-da00-a750-be097c7ceb32@xxxxxxx/
CC: Rob Herring <robh+dt@xxxxxxxxxx>
CC: Frank Rowand <frowand.list@xxxxxxxxx>
Fixes: e0d072782c73 ("dma-mapping: introduce DMA range map, supplanting dma_pfn_offset"),
Suggested-by: Robin Murphy <robin.murphy@xxxxxxx>
Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx>
Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
---
drivers/of/device.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/of/device.c b/drivers/of/device.c
index aedfaaafd3e7..1122daa8e273 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -162,9 +162,11 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
mask = DMA_BIT_MASK(ilog2(end) + 1);
dev->coherent_dma_mask &= mask;
*dev->dma_mask &= mask;
- /* ...but only set bus limit if we found valid dma-ranges earlier */
- if (!ret)
+ /* ...but only set bus limit and range map if we found valid dma-ranges earlier */
+ if (!ret) {
dev->bus_dma_limit = end;
+ dev->dma_range_map = map;
+ }
coherent = of_dma_is_coherent(np);
dev_dbg(dev, "device is%sdma coherent\n",
@@ -172,6 +174,9 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
iommu = of_iommu_configure(dev, np, id);
if (PTR_ERR(iommu) == -EPROBE_DEFER) {
+ /* Don't touch range map if it wasn't set from a valid dma-ranges */
+ if (!ret)
+ dev->dma_range_map = NULL;
kfree(map);
return -EPROBE_DEFER;
}
@@ -181,7 +186,6 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);
- dev->dma_range_map = map;
return 0;
}
EXPORT_SYMBOL_GPL(of_dma_configure_id);
--
2.18.0
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