[PATCH v11 15/16] PCI/PME: Add pcie_walk_rcec() to RCEC PME handling

From: Sean V Kelley
Date: Tue Nov 17 2020 - 14:21:05 EST


Root Complex Event Collectors (RCEC) appear as peers of Root Ports and also
have the PME capability. As with AER, there is a need to be able to walk
the RCiEPs associated with their RCEC for purposes of acting upon them with
callbacks.

Add RCEC support through the use of pcie_walk_rcec() to the current PME
service driver and attach the PME service driver to the RCEC device.

Co-developed-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
Link: https://lore.kernel.org/r/20201002184735.1229220-14-seanvk.dev@xxxxxxxxxxxxxxxx
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
Signed-off-by: Sean V Kelley <sean.v.kelley@xxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
---
drivers/pci/pcie/pme.c | 15 +++++++++++----
drivers/pci/pcie/portdrv_core.c | 9 +++------
2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/drivers/pci/pcie/pme.c b/drivers/pci/pcie/pme.c
index 6a32970bb731..87799166c96a 100644
--- a/drivers/pci/pcie/pme.c
+++ b/drivers/pci/pcie/pme.c
@@ -310,7 +310,10 @@ static int pcie_pme_can_wakeup(struct pci_dev *dev, void *ign)
static void pcie_pme_mark_devices(struct pci_dev *port)
{
pcie_pme_can_wakeup(port, NULL);
- if (port->subordinate)
+
+ if (pci_pcie_type(port) == PCI_EXP_TYPE_RC_EC)
+ pcie_walk_rcec(port, pcie_pme_can_wakeup, NULL);
+ else if (port->subordinate)
pci_walk_bus(port->subordinate, pcie_pme_can_wakeup, NULL);
}

@@ -320,10 +323,15 @@ static void pcie_pme_mark_devices(struct pci_dev *port)
*/
static int pcie_pme_probe(struct pcie_device *srv)
{
- struct pci_dev *port;
+ struct pci_dev *port = srv->port;
struct pcie_pme_service_data *data;
int ret;

+ /* Limit to Root Ports or Root Complex Event Collectors */
+ if ((pci_pcie_type(port) != PCI_EXP_TYPE_RC_EC) &&
+ (pci_pcie_type(port) != PCI_EXP_TYPE_ROOT_PORT))
+ return -ENODEV;
+
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
@@ -333,7 +341,6 @@ static int pcie_pme_probe(struct pcie_device *srv)
data->srv = srv;
set_service_data(srv, data);

- port = srv->port;
pcie_pme_interrupt_enable(port, false);
pcie_clear_root_pme_status(port);

@@ -445,7 +452,7 @@ static void pcie_pme_remove(struct pcie_device *srv)

static struct pcie_port_service_driver pcie_pme_driver = {
.name = "pcie_pme",
- .port_type = PCI_EXP_TYPE_ROOT_PORT,
+ .port_type = PCIE_ANY_PORT,
.service = PCIE_PORT_SERVICE_PME,

.probe = pcie_pme_probe,
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index 50a9522ab07d..e1fed6649c41 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -233,12 +233,9 @@ static int get_port_device_capability(struct pci_dev *dev)
}
#endif

- /*
- * Root ports are capable of generating PME too. Root Complex
- * Event Collectors can also generate PMEs, but we don't handle
- * those yet.
- */
- if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT &&
+ /* Root Ports and Root Complex Event Collectors may generate PMEs */
+ if ((pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
+ pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC) &&
(pcie_ports_native || host->native_pme)) {
services |= PCIE_PORT_SERVICE_PME;

--
2.29.2