From: Bharat Kumar Gogada <bharat.kumar.gogada@xxxxxxxxxx>
As per section 6.2.4.1.2, 6.2.6 in PCIe r4.0 (and later versions),
platform-specific System Errors like AER can be delivered via platform-
specific interrupt lines.
This patch adds the init_platform_service_irqs() hook to struct
pci_host_bridge, making it possible that platforms may implement this
function to hook IRQs for these platform-specific System Errors, like
AER.
If these platform-specific service IRQs have been successfully
installed via pcie_init_platform_service_irqs(),
pcie_init_service_irqs() is skipped.
Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@xxxxxxxxxx>
Signed-off-by: Stefan Roese <sr@xxxxxxx>
Cc: Bjorn Helgaas <helgaas@xxxxxxxxxx>
Cc: Pali Rohár <pali@xxxxxxxxxx>
Cc: Michal Simek <michal.simek@xxxxxxxxxx>
---
drivers/pci/pcie/portdrv_core.c | 39 ++++++++++++++++++++++++++++++++-
include/linux/pci.h | 2 ++
2 files changed, 40 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index e7dcb1f23210..27b990cedb4c 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -190,6 +190,31 @@ static int pcie_init_service_irqs(struct pci_dev *dev, int *irqs, int mask)
return 0;
}
+/**
+ * pcie_init_platform_service_irqs - initialize platform service irqs for
+ * platform-specific System Errors
+ * @dev: PCI Express port to handle
+ * @irqs: Array of irqs to populate
+ * @mask: Bitmask of capabilities
+ *
+ * Return value: -ENODEV, in case no platform-specific IRQ is available
+ */
+static int pcie_init_platform_service_irqs(struct pci_dev *dev,
+ int *irqs, int mask)
+{
+ struct pci_host_bridge *bridge;
+
+ if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
+ bridge = pci_find_host_bridge(dev->bus);
+ if (bridge && bridge->init_platform_service_irqs) {
+ return bridge->init_platform_service_irqs(dev, irqs,
+ mask);
+ }
+ }
+
+ return -ENODEV;
+}
+
/**
* get_port_device_capability - discover capabilities of a PCI Express port
* @dev: PCI Express port to examine
@@ -335,7 +360,19 @@ int pcie_port_device_register(struct pci_dev *dev)
irq_services |= PCIE_PORT_SERVICE_DPC;
irq_services &= capabilities;
- if (irq_services) {
+ /*
+ * Some platforms have dedicated interrupts from root complex to
+ * interrupt controller for PCIe platform-specific System Errors
+ * like AER/PME etc., check if the platform registered with any such
+ * IRQ.
+ */
+ status = pcie_init_platform_service_irqs(dev, irqs, capabilities);
+
+ /*
+ * Only install service irqs, when the platform-specific hook was
+ * unsuccessful
+ */
+ if (irq_services && status) {
/*
* Initialize service IRQs. Don't use service devices that
* require interrupts if there is no way to generate them.
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 18a75c8e615c..fb8aad3cb460 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -554,6 +554,8 @@ struct pci_host_bridge {
u8 (*swizzle_irq)(struct pci_dev *, u8 *); /* Platform IRQ swizzler */
int (*map_irq)(const struct pci_dev *, u8, u8);
void (*release_fn)(struct pci_host_bridge *);
+ int (*init_platform_service_irqs)(struct pci_dev *dev, int *irqs,
+ int plat_mask);
void *release_data;
unsigned int ignore_reset_delay:1; /* For entire hierarchy */
unsigned int no_ext_tags:1; /* No Extended Tags */
--
2.34.1
