On Tue, Sep 01, 2020 at 02:33:56PM -0400, Samuel Dionne-Riel wrote:
> On Tue, 1 Sep 2020 17:42:49 +0100
> Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> wrote:
>
> > On Tue, Sep 01, 2020 at 04:37:42PM +0100, Marc Zyngier wrote:
> > > On 2020-09-01 04:45, Samuel Dionne-Riel wrote:
> > > > - if (pci_is_root_bus(bus->parent) && dev > 0)
> > > > + if (bus->primary == rockchip->root_bus_nr && dev > 0)
> >
> > Can you dump bus->primary when this condition is hit please ?
>
> With the following diff
>
> ---
> @@ -79,6 +79,8 @@ static int rockchip_pcie_valid_device(struct rockchip_pcie *rockchip,
> * do not read more than one device on the bus directly attached
> * to RC's downstream side.
> */
> + printk("[!!] // bus->parent (%d)\n", bus->parent);
Please print a pointer as a pointer and print both bus and bus->parent.
> + printk("[!!] bus->primary (%d) == rockchip->root_bus_nr (%d) && dev (%d) > 0\n", bus->primary, rockchip->root_bus_nr, dev);
> if (bus->primary == rockchip->root_bus_nr && dev > 0)
> return 0;
>
> --
>
> I get two kind of results
>
> [ 1.692913] [!!] // bus->parent (0)
> [ 1.692917] [!!] bus->primary (0) == rockchip->root_bus_nr (0) && dev (0) > 0
>
> and
>
> [ 1.693055] [!!] // bus->parent (-256794624)
> [ 1.693058] [!!] bus->primary (0) == rockchip->root_bus_nr (0) && dev (0) > 0
>
Looks like this is the condition that pci_is_root_bus(bus->parent) is
not hitting.
[...]
> > > > + /* HACK; ~equiv to last param of
> > > > pci_parse_request_of_pci_ranges */
> > > > + bus_res = (resource_list_first_type(&bridge->windows,
> > > > IORESOURCE_MEM))->res;
> >
> > IORESOURCE_MEM ? I am a bit puzzled by this hack, what is it supposed
> > to do ?
>
> It's not really supposed to do anything. I only needed access to
> bus_res for bus_res->start to keep as root_bus_nr. My complete lack of
> familiarity with all of this meant that I simply borrowed something
> that was in use in another function to give me the bus_res.
You are accessing a resource IORESOURCE_MEM that has nothing to do
with bus numbers.
s/IORESOURCE_MEM/IORESOURCE_BUS
should be better ;-)
Lorenzo
