On 20.01.2016 13:38, Lorenzo Pieralisi wrote:
On Wed, Jan 20, 2016 at 12:20:07PM +0100, Tomasz Nowicki wrote:
On 19.01.2016 17:02, Lorenzo Pieralisi wrote:
On Wed, Jan 13, 2016 at 02:20:57PM +0100, Tomasz Nowicki wrote:
[...]
device via pci_create_root_bus parameter (as the ACPI device type)
I do not understand what you mean by "as the ACPI device type".
See below.
and using ACPI_COMPANION_SET in core code for ACPI boot method. ACPI_COMPANION_SET is safe to run for all cases DT, ACPI and DT&ACPI.
Suggested-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com Signed-off-by: Tomasz Nowicki tn@semihalf.com
drivers/acpi/pci_root.c | 5 ++++- drivers/pci/probe.c | 2 ++ 2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index ae3fe4e..a65c8c2 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -846,7 +846,10 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
pci_acpi_root_add_resources(info); pci_add_resource(&info->resources, &root->secondary);
- bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
- /* Root bridge device needs to be sure of parent ACPI type */
- ACPI_COMPANION_SET(&device->dev, device);
I do not understand why the code above is needed, can you elaborate please ?
This makes sure that device->dev can be identified as ACPI device, so we can use to_acpi_device_node() and assign companion safely below.
I do not follow. If you refer to the fwnode handle type, that is already set by ACPI core code (before acpi_pci_root_add() is called, in acpi_init_device_object()).
acpi_init_device_object() sets ACPI fwnode handle type only for "device", but not for "device->dev" which is what is passed as an argument to pci_create_root_bus().
Without ACPI_COMPANION_SET(&device->dev, device) here, no one can be sure if we have ACPI device in pci_create_root_bus().
Did you add the code above to solve a real issue you encountered ?
Yes. You can try to run series with this patch:
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index 88c9d20..1b74bf6 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -967,7 +967,11 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root, pci_add_resource(&info->resources, &root->secondary);
- /* Root bridge device needs to be sure of parent ACPI type */ - ACPI_COMPANION_SET(&device->dev, device); + if (to_acpi_device_node(device->dev.fwnode) == NULL) + pr_err("NON-ACPI TYPE\n"); + else + pr_err("ACPI TYPE\n"); + bus = pci_create_root_bus(&device->dev, busnum, ops->pci_ops, sysdata, &info->resources);
Thanks, Tomasz