[PATCH V2 1/2] PCI: of: Warn if non-prefetchable memory aperture size is > 32-bit

From: Vidya Sagar
Date: Wed Nov 18 2020 - 09:46:59 EST


As per PCIe spec r5.0, sec 7.5.1.3.8 only 32-bit BAR registers are defined
for non-prefetchable memory and hence a warning should be reported when
the size of them go beyond 32-bits.

Tested-by: Thierry Reding <treding@xxxxxxxxxx>
Tested-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
---
V2:
* Added 'Tested-by' and 'Reviewed-by'

drivers/pci/of.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index ac24cd5439a9..5ea472ae22ac 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -556,6 +556,11 @@ static int pci_parse_request_of_pci_ranges(struct device *dev,
break;
case IORESOURCE_MEM:
res_valid |= !(res->flags & IORESOURCE_PREFETCH);
+
+ if (!(res->flags & IORESOURCE_PREFETCH))
+ if (upper_32_bits(resource_size(res)))
+ dev_warn(dev, "Memory resource size exceeds max for 32 bits\n");
+
break;
}
}
--
2.17.1