On Wed, Aug 17, 2016 at 6:02 PM, Aaron Durbin <adurbin@xxxxxxxxxx> wrote:
> On Tue, Aug 16, 2016 at 2:15 AM, Mika Westerberg
> <mika.westerberg@xxxxxxxxxxxxxxx> wrote:
>> On Fri, Aug 12, 2016 at 11:45:30AM -0500, Aaron Durbin wrote:
>>> Was anyone able to take a look into a solution for the current
>>> problem? Again, please feel free to ask if anyone would like help
>>> testing potential solutions.
>>
>> Below is one proposal for fixing the issue. It is just a prototype and
>> I'm not sure if it takes everything needed into account. Would you be
>> able to try it out and let us know if it works for you?
>
> Yes. I'll give it a go. I'm traveling this week so it won't likely be
> til early next week. Thanks for the proposed fix. I'll report back on
> my findings.
>
Sorry for the late response. I tried the patch and it works with ACPI
devices in a hierarchy below PCI devices. I didn't have any ACPI
drivers probed but I was able to hang 2 ACPI devices off of a BAR that
had a driver for the PCI device without any resource conflicts
(snippet from /proc/iomem):
c2a43000-c2a43fff : 0000:00:1b.0
c2a43000-c2a437ff : GOOG1234:00
c2a43800-c2a43fff : GOOG1235:00
One observation that I don't think matters much, but I wanted to write
it down in case anyone pulls this thread up again. In the case of
finding the parent resource, the ACPI devcie's resources won't show up
in the resource tree until the pci parent devices' resources are
inserted.
>>
>> diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c
>> index 159f7f19abce..72068415f806 100644
>> --- a/drivers/acpi/acpi_platform.c
>> +++ b/drivers/acpi/acpi_platform.c
>> @@ -18,6 +18,7 @@
>> #include <linux/module.h>
>> #include <linux/dma-mapping.h>
>> #include <linux/platform_device.h>
>> +#include <linux/pci.h>
>>
>> #include "internal.h"
>>
>> @@ -30,6 +31,35 @@ static const struct acpi_device_id forbidden_id_list[] = {
>> {"", 0},
>> };
>>
>> +static struct resource *acpi_find_parent_resource(struct acpi_device *adev,
>> + struct resource *res)
>> +{
>> + struct device *parent;
>> +
>> + parent = acpi_get_first_physical_node(adev->parent);
>> + if (!parent)
>> + return NULL;
>> +
>> +#if IS_ENABLED(CONFIG_PCI)
>> + if (dev_is_pci(parent)) {
>> + struct pci_dev *pdev = to_pci_dev(parent);
>> +
>> + if (!pci_is_bridge(pdev)) {
>> + int i;
>> +
>> + for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
>> + struct resource *r = &pdev->resource[i];
>> +
>> + if (r->start && resource_contains(r, res))
>> + return r;
>> + }
>> + }
>> + }
>> +#endif
>> +
>> + return NULL;
>> +}
>> +
>> /**
>> * acpi_create_platform_device - Create platform device for ACPI device node
>> * @adev: ACPI device node to create a platform device for.
>> @@ -69,8 +99,17 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *adev)
>> return ERR_PTR(-ENOMEM);
>> }
>> count = 0;
>> - list_for_each_entry(rentry, &resource_list, node)
>> - resources[count++] = *rentry->res;
>> + list_for_each_entry(rentry, &resource_list, node) {
>> + struct resource *res = &resources[count++];
>> +
>> + *res = *rentry->res;
>> + /*
>> + * If the device has parent we need to take its
>> + * resources into account as well because this
>> + * device might consume part of those.
>> + */
>> + res->parent = acpi_find_parent_resource(adev, res);
>> + }
>>
>> acpi_dev_free_resource_list(&resource_list);
>> }
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
