2021-09-24 22:49:14

by Sergio Paracuellos

Subject: [PATCH 6/6] staging: mt7621-pci: properly adjust base address for the IO window

The value to adjust in the bridge register RALINK_PCI_IOBASE must take into
account the raw value from DT, not only the translated linux port number.
As long as io_offset is zero, the two are the same, but if you were to use
multiple host bridge in the system, or pick a different bus address in DT,
you can have a nonzero io_offset. At this means to take into account the
bus address which is used to calculate this offset, substracting it from
the IO resource start address.

Signed-off-by: Sergio Paracuellos <[email protected]>
---
drivers/staging/mt7621-pci/pci-mt7621.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/mt7621-pci/pci-mt7621.c b/drivers/staging/mt7621-pci/pci-mt7621.c
index 6acfc94a16e7..503cb1fca2e0 100644
--- a/drivers/staging/mt7621-pci/pci-mt7621.c
+++ b/drivers/staging/mt7621-pci/pci-mt7621.c
@@ -482,7 +482,7 @@ static int mt7621_pcie_enable_ports(struct pci_host_bridge *host)

/* Setup MEMWIN and IOWIN */
pcie_write(pcie, 0xffffffff, RALINK_PCI_MEMBASE);
- pcie_write(pcie, entry->res->start, RALINK_PCI_IOBASE);
+ pcie_write(pcie, entry->res->start - entry->offset, RALINK_PCI_IOBASE);

list_for_each_entry(port, &pcie->ports, list) {
if (port->enabled) {
--
2.25.1

2021-09-25 17:34:37

by Arnd Bergmann

Subject: Re: [PATCH 6/6] staging: mt7621-pci: properly adjust base address for the IO window

On Fri, Sep 24, 2021 at 11:11 PM Sergio Paracuellos
<[email protected]> wrote:
>
> The value to adjust in the bridge register RALINK_PCI_IOBASE must take into
> account the raw value from DT, not only the translated linux port number.
> As long as io_offset is zero, the two are the same, but if you were to use
> multiple host bridge in the system, or pick a different bus address in DT,
> you can have a nonzero io_offset. At this means to take into account the
> bus address which is used to calculate this offset, substracting it from
> the IO resource start address.
>
> Signed-off-by: Sergio Paracuellos <[email protected]>

Acked-by: Arnd Bergmann <[email protected]>