From 660c486590aa4190969653218643b3a4e5660f2b Mon Sep 17 00:00:00 2001
From: Vidya Sagar <vidyas@nvidia.com>
Date: Tue, 17 Nov 2020 22:23:12 +0530
Subject: [PATCH] PCI: dwc: Set 32-bit DMA mask for MSI target address
allocation
Set DMA mask to 32-bit while allocating the MSI target address so that
the address is usable for both 32-bit and 64-bit MSI capable devices.
Throw a warning if it fails to set the mask to 32-bit to alert that
devices that are only 32-bit MSI capable may not work properly.
Link: https://lore.kernel.org/r/20201117165312.25847-1-vidyas@nvidia.com
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
---
drivers/pci/controller/dwc/pcie-designware-host.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 99ef808a40a95..516b151e0ef32 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -396,6 +396,14 @@ 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");
+ }
+
pp->msi_data = dma_map_single_attrs(pci->dev, &pp->msi_msg,
sizeof(pp->msi_msg),
DMA_FROM_DEVICE,
--
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