If dma_mask is more than 32 bits this will trigger an error occurs when
dma_map_single_attrs() is performed.
dma_map_single_attrs() -> dma_map_page_attrs()->
error return in dma_direct_map_page().
On ARTPEC-8, this fails with:
artpec8-pcie 17200000.pcie: DMA addr 0x0000000106b052c8+2 overflow
(mask ffffffff, bus limit 27fffffff)
There is no sequence that re-sets dev->dma_mask to more than 32 bits
before call dma_map_single_attrs().
The dev->dma_mask is first set just prior to the dw_pcie_host_init() call.
Therefore, the check logic was modified to be performed only when
the dev-dma_mask is not set larger than 32 bits.
Always setting dma_mask to 32 bits is not always correct,
for example the ARTPEC-8 is an arm64 platform, and can access
more than 32 bits
Signed-off-by: Wangseok Lee <wangseok.lee@xxxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-designware-host.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 2fa86f3..7e25958 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -388,9 +388,11 @@ int dw_pcie_host_init(struct pcie_port *pp)
dw_chained_msi_isr,
pp);
- ret = dma_set_mask(pci->dev, DMA_BIT_MASK(32));
- if (ret)
- dev_warn(pci->dev, "Failed to set DMA mask to 32-bit. Devices with only 32-bit MSI support may not work properly\n");
+ if (!(*dev->dma_mask & ~(GENMASK(31, 0)))) {
+ ret = dma_set_mask(pci->dev, DMA_BIT_MASK(32));
+ if (ret)
+ dev_warn(pci->dev, "Failed to set DMA mask to 32-bit. Devices with only 32-bit MSI support may not work properly\n");
+ }
pp->msi_data = dma_map_single_attrs(pci->dev, &pp->msi_msg,
sizeof(pp->msi_msg),
--
2.9.5
