[PATCH v12 01/13] PCI: dwc: Use resource start as iomap() input in dw_pcie_pme_turn_off()

From: Bjorn Helgaas
Date: Sat Mar 15 2025 - 16:16:11 EST


From: Frank Li <Frank.Li@xxxxxxx>

The msg_res region translates writes into PCIe Message TLPs. Previously we
mapped this region using atu.cpu_addr, the input address programmed into
the ATU.

"cpu_addr" is a misnomer because when a bus fabric translates addresses
between the CPU and the ATU, the ATU input address is different from the
CPU address. A future patch will rename "cpu_addr" and correct the value
to be the ATU input address instead of the CPU physical address.

Map the msg_res region before writing to it using the msg_res resource
start, a CPU physical address.

Link: https://lore.kernel.org/r/20250313-pci_fixup_addr-v11-1-01d2313502ab@xxxxxxx
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-designware-host.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index ffaded8f2df7..ae3fd2a5dbf8 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -908,7 +908,7 @@ static int dw_pcie_pme_turn_off(struct dw_pcie *pci)
if (ret)
return ret;

- mem = ioremap(atu.cpu_addr, pci->region_align);
+ mem = ioremap(pci->pp.msg_res->start, pci->region_align);
if (!mem)
return -ENOMEM;

--
2.34.1