PCI/PME: Add pcie_walk_rcec() to RCEC PME handling

mainline inclusion
from mainline-v5.11-rc1
commit 9a2f604f
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I51U4T
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9a2f604f44979e0effa8cf067e5a8ecda729f23b

--------------------------------------------------------------------------

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: NQiuxu Zhuo <qiuxu.zhuo@intel.com>
Link: https://lore.kernel.org/r/20201121001036.8560-15-sean.v.kelley@intel.com
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # non-native/no RCEC
Signed-off-by: NQiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: NSean V Kelley <sean.v.kelley@intel.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJiefeng Ou <oujiefeng@h-partners.com>
Reviewed-by: NJay Fang <f.fangjian@huawei.com>
Reviewed-by: NXiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

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 +323,16 @@ 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 type = pci_pcie_type(port);
 	int ret;
 
+	/* Limit to Root Ports or Root Complex Event Collectors */
+	if (type != PCI_EXP_TYPE_RC_EC &&
+	    type != PCI_EXP_TYPE_ROOT_PORT)
+		return -ENODEV;
+
 	data = kzalloc(sizeof(*data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
@@ -333,7 +342,6 @@ 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 +453,7 @@ 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,

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;