[PATCH v6 3/3] pci:add support aer/pme interrupts with none MSI/MSI-X/INTx mode

Po Liu
2016-09-30T09:40:19Z

On some platforms, root port doesn't support MSI/MSI-X/INTx in RC mode.
When chip support the aer/pme interrupts with none MSI/MSI-X/INTx mode,
maybe there is interrupt line for aer pme etc. Search the interrupt
number in the fdt file. Then fixup the dev->irq with it.

Signed-off-by: Po Liu <po.liu@nxp.com>
---
changes for v6:
- modify bindings for "aer""pme";
- changing to the hood method to implement the aer pme interrupt;
- add pme interrupt in the same way;

.../devicetree/bindings/pci/layerscape-pci.txt | 13 +++++--
arch/arm/kernel/bios32.c | 43 ++++++++++++++++++++++
arch/arm64/kernel/pci.c | 43 ++++++++++++++++++++++
drivers/pci/pcie/portdrv_core.c | 31 +++++++++++++++-
include/linux/pci.h | 1 +
5 files changed, 126 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/layerscape-pci.txt b/Documentation/devicetree/bindings/pci/layerscape-pci.txt
index 41e9f55..51ed49e 100644
--- a/Documentation/devicetree/bindings/pci/layerscape-pci.txt
+++ b/Documentation/devicetree/bindings/pci/layerscape-pci.txt
@@ -18,8 +18,12 @@ Required properties:
- reg: base addresses and lengths of the PCIe controller
- interrupts: A list of interrupt outputs of the controller. Must contain an
entry for each entry in the interrupt-names property.
-- interrupt-names: Must include the following entries:
- "intr": The interrupt that is asserted for controller interrupts
+- interrupt-names: It could include the following entries:
+ "aer": Asserted for aer interrupt when chip support the aer interrupt with
+ none MSI/MSI-X/INTx mode,but there is interrupt line for aer.
+ "pme": Asserted for pme interrupt when chip support the pme interrupt with
+ none MSI/MSI-X/INTx mode,but there is interrupt line for pme.
+ ......
- fsl,pcie-scfg: Must include two entries.
The first entry must be a link to the SCFG device node
The second entry must be '0' or '1' based on physical PCIe controller index.
@@ -35,8 +39,9 @@ Example:
reg = <0x00 0x03400000 0x0 0x00010000 /* controller registers */
0x40 0x00000000 0x0 0x00002000>; /* configuration space */
reg-names = "regs", "config";
- interrupts = <GIC_SPI 177 IRQ_TYPE_LEVEL_HIGH>; /* controller interrupt */
- interrupt-names = "intr";
+ interrupts = <GIC_SPI 176 IRQ_TYPE_LEVEL_HIGH>, /* aer interrupt */
+ <GIC_SPI 177 IRQ_TYPE_LEVEL_HIGH>; /* pme interrupt */
+ interrupt-names = "aer", "pme";
fsl,pcie-scfg = <&scfg 0>;
#address-cells = <3>;
#size-cells = <2>;
diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
index 2f0e077..d2f4869 100644
--- a/arch/arm/kernel/bios32.c
+++ b/arch/arm/kernel/bios32.c
@@ -11,6 +11,8 @@
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/io.h>
+#include <linux/of_irq.h>
+#include <linux/pcieport_if.h>

#include <asm/mach-types.h>
#include <asm/mach/map.h>
@@ -64,6 +66,47 @@ void pcibios_report_status(u_int status_mask, int warn)
}

/*
+ * Check device tree if the service interrupts are there
+ */
+int pcibios_check_service_irqs(struct pci_dev *dev, int *irqs, int mask)
+{
+ int ret, count = 0;
+ struct device_node *np = NULL;
+
+ if (dev->bus->dev.of_node)
+ np = dev->bus->dev.of_node;
+
+ if (np == NULL)
+ return 0;
+
+ if (!IS_ENABLED(CONFIG_OF_IRQ))
+ return 0;
+
+ /* If root port doesn't support MSI/MSI-X/INTx in RC mode,
+ * request irq for aer
+ */
+ if (mask & PCIE_PORT_SERVICE_AER) {
+ ret = of_irq_get_byname(np, "aer");
+ if (ret > 0) {
+ irqs[PCIE_PORT_SERVICE_AER_SHIFT] = ret;
+ count++;
+ }
+ }
+
+ if (mask & PCIE_PORT_SERVICE_PME) {
+ ret = of_irq_get_byname(np, "pme");
+ if (ret > 0) {
+ irqs[PCIE_PORT_SERVICE_PME_SHIFT] = ret;
+ count++;
+ }
+ }
+
+ /* TODO: add more service interrupts if there it is in the device tree*/
+
+ return count;
+}
+
+/*
* We don't use this to fix the device, but initialisation of it.
* It's not the correct use for this, but it works.
* Note that the arbiter/ISA bridge appears to be buggy, specifically in
diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index acf3872..4a3c61a 100644
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -17,6 +17,8 @@
#include <linux/mm.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
+#include <linux/of_irq.h>
+#include <linux/pcieport_if.h>
#include <linux/pci.h>
#include <linux/pci-acpi.h>
#include <linux/pci-ecam.h>
@@ -55,6 +57,47 @@ int pcibios_alloc_irq(struct pci_dev *dev)
}

/*
+ * Check device tree if the service interrupts are there
+ */
+int pcibios_check_service_irqs(struct pci_dev *dev, int *irqs, int mask)
+{
+ int ret, count = 0;
+ struct device_node *np = NULL;
+
+ if (dev->bus->dev.of_node)
+ np = dev->bus->dev.of_node;
+
+ if (np == NULL)
+ return 0;
+
+ if (!IS_ENABLED(CONFIG_OF_IRQ))
+ return 0;
+
+ /* If root port doesn't support MSI/MSI-X/INTx in RC mode,
+ * request irq for aer
+ */
+ if (mask & PCIE_PORT_SERVICE_AER) {
+ ret = of_irq_get_byname(np, "aer");
+ if (ret > 0) {
+ irqs[PCIE_PORT_SERVICE_AER_SHIFT] = ret;
+ count++;
+ }
+ }
+
+ if (mask & PCIE_PORT_SERVICE_PME) {
+ ret = of_irq_get_byname(np, "pme");
+ if (ret > 0) {
+ irqs[PCIE_PORT_SERVICE_PME_SHIFT] = ret;
+ count++;
+ }
+ }
+
+ /* TODO: add more service interrupts if there it is in the device tree*/
+
+ return count;
+}
+
+/*
* raw_pci_read/write - Platform-specific PCI config space access.
*/
int raw_pci_read(unsigned int domain, unsigned int bus,
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index e9270b4..34b6dae 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -44,6 +44,19 @@ static void release_pcie_device(struct device *dev)
}

/**
+ * pcibios_check_service_irqs - check irqs in the device tree
+ * @dev: PCI Express port to handle
+ * @irqs: Array of irqs to populate
+ * @mask: Bitmask of port capabilities returned by get_port_device_capability()
+ *
+ * Return value: 0 means no service irqs in the device tree
+ *
+ */
+int __weak pcibios_check_service_irqs(struct pci_dev *dev, int *irqs, int mask)
+{
+ return 0;
+}
+/**
* pcie_port_msix_add_entry - add entry to given array of MSI-X entries
* @entries: Array of MSI-X entries
* @new_entry: Index of the entry to add to the array
@@ -200,6 +213,21 @@ static int pcie_port_enable_msix(struct pci_dev *dev, int *vectors, int mask)
static int init_service_irqs(struct pci_dev *dev, int *irqs, int mask)
{
int i, irq = -1;
+ int ret;
+
+ /* Check if some platforms owns independent irq pins for AER/PME etc.
+ * Some platforms may own independent AER/PME interrupts and set
+ * them in the device tree file.
+ */
+ for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
+ irqs[i] = -1;
+
+ ret = pcibios_check_service_irqs(dev, irqs, mask);
+ if (ret) {
+ if (dev->irq)
+ irq = dev->irq;
+ goto no_msi;
+ }

/*
* If MSI cannot be used for PCIe PME or hotplug, we have to use
@@ -226,7 +254,8 @@ static int init_service_irqs(struct pci_dev *dev, int *irqs, int mask)

no_msi:
for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
- irqs[i] = irq;
+ if (irqs[i] == -1)
+ irqs[i] = irq;
irqs[PCIE_PORT_SERVICE_VC_SHIFT] = -1;

if (irq < 0)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 2599a98..c80f2d0 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1793,6 +1793,7 @@ void pcibios_release_device(struct pci_dev *dev);
void pcibios_penalize_isa_irq(int irq, int active);
int pcibios_alloc_irq(struct pci_dev *dev);
void pcibios_free_irq(struct pci_dev *dev);
+int pcibios_check_service_irqs(struct pci_dev *dev, int *irqs, int mask);

#ifdef CONFIG_HIBERNATE_CALLBACKS
extern struct dev_pm_ops pcibios_pm_ops;
--
2.1.0.27.g96db324