[PATCH next 1/2] PCI: keystone: add pci error irq handler
From: Murali Karicheri
Date: Tue Mar 22 2016 - 15:53:25 EST
Keystone PCI hardware generates error interrupts at RC using platform
irq instead of standard msi/legacy irq. Add a simple error handler that
logs the fatal interrupt status to the console.
Signed-off-by: Murali Karicheri <m-karicheri2@xxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Pawel Moll <pawel.moll@xxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Ian Campbell <ijc+devicetree@xxxxxxxxxxxxxx>
Cc: Kumar Gala <galak@xxxxxxxxxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
---
.../devicetree/bindings/pci/pci-keystone.txt | 1 +
drivers/pci/host/pci-keystone-dw.c | 46 ++++++++++++++++++++++
drivers/pci/host/pci-keystone.c | 32 +++++++++++++++
drivers/pci/host/pci-keystone.h | 6 +++
4 files changed, 85 insertions(+)
diff --git a/Documentation/devicetree/bindings/pci/pci-keystone.txt b/Documentation/devicetree/bindings/pci/pci-keystone.txt
index 54eae29..d08a4d5 100644
--- a/Documentation/devicetree/bindings/pci/pci-keystone.txt
+++ b/Documentation/devicetree/bindings/pci/pci-keystone.txt
@@ -56,6 +56,7 @@ Optional properties:-
phy-names: name of the Generic Keystine SerDes phy for PCI
- If boot loader already does PCI link establishment, then phys and
phy-names shouldn't be present.
+ interrupts: platform interrupt for error interrupts.
Designware DT Properties not applicable for Keystone PCI
diff --git a/drivers/pci/host/pci-keystone-dw.c b/drivers/pci/host/pci-keystone-dw.c
index ed34c95..524901d 100644
--- a/drivers/pci/host/pci-keystone-dw.c
+++ b/drivers/pci/host/pci-keystone-dw.c
@@ -53,6 +53,29 @@
#define IRQ_STATUS 0x184
#define MSI_IRQ_OFFSET 4
+/*
+ * error IRQ bits. Enable following errors
+ * - ERR_AER - ECRC error - BIT(5)
+ * - ERR_AXI - AXI tag lookup fatal error BIT(4)
+ * - ERR_CORR - Correctable error BIT(3)
+ * - ERR_NONFATAL - Non fatal error BIT(2)
+ * - ERR_FATAL - Fatal error BIT(1)
+ * - ERR_SYS - System error (fatal, nonfatal or correctable error)
+ */
+#define ERR_AER BIT(5)
+#define ERR_AXI BIT(4)
+#define ERR_CORR BIT(3)
+#define ERR_NONFATAL BIT(2)
+#define ERR_FATAL BIT(1)
+#define ERR_SYS BIT(0)
+#define ERR_IRQ_ALL (ERR_AER | ERR_AXI | ERR_CORR | \
+ ERR_NONFATAL | ERR_FATAL | ERR_SYS)
+#define ERR_FATAL_IRQ (ERR_FATAL | ERR_AXI)
+#define ERR_IRQ_STATUS_RAW 0x1c0
+#define ERR_IRQ_STATUS 0x1c4
+#define ERR_IRQ_ENABLE_SET 0x1c8
+#define ERR_IRQ_ENABLE_CLR 0x1cc
+
/* Config space registers */
#define DEBUG0 0x728
@@ -248,6 +271,29 @@ void ks_dw_pcie_handle_legacy_irq(struct keystone_pcie *ks_pcie, int offset)
writel(offset, ks_pcie->va_app_base + IRQ_EOI);
}
+void ks_dw_pcie_enable_error_irq(void __iomem *reg_base)
+{
+ writel(ERR_IRQ_ALL, reg_base + ERR_IRQ_ENABLE_SET);
+}
+
+bool ks_dw_pcie_handle_error_irq(struct device *dev, void __iomem *reg_base)
+{
+ u32 status;
+ bool ret = false;
+
+ status = readl(reg_base + ERR_IRQ_STATUS_RAW) & ERR_IRQ_ALL;
+ if (status) {
+ /* The PCIESS interrupt status buts are "write 1 to clear" */
+ if (status & ERR_FATAL_IRQ)
+ dev_err(dev, "PCIE fatal error detected\n");
+
+ /* ack the irq event. */
+ writel(status, reg_base + ERR_IRQ_STATUS);
+ ret = true;
+ }
+ return ret;
+}
+
static void ks_dw_pcie_ack_legacy_irq(struct irq_data *d)
{
}
diff --git a/drivers/pci/host/pci-keystone.c b/drivers/pci/host/pci-keystone.c
index b71f55b..299f2f0 100644
--- a/drivers/pci/host/pci-keystone.c
+++ b/drivers/pci/host/pci-keystone.c
@@ -15,6 +15,7 @@
#include <linux/irqchip/chained_irq.h>
#include <linux/clk.h>
#include <linux/delay.h>
+#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/msi.h>
@@ -226,6 +227,10 @@ static void ks_pcie_setup_interrupts(struct keystone_pcie *ks_pcie)
ks_pcie);
}
}
+
+ /* enable error interrupt */
+ if (ks_pcie->error_irq > 0)
+ ks_dw_pcie_enable_error_irq(ks_pcie->va_app_base);
}
/*
@@ -289,6 +294,16 @@ static struct pcie_host_ops keystone_pcie_host_ops = {
.scan_bus = ks_dw_pcie_v3_65_scan_bus,
};
+static irqreturn_t pcie_err_irq_handler(int irq, void *priv)
+{
+ struct keystone_pcie *ks_pcie = priv;
+
+ if (ks_dw_pcie_handle_error_irq(ks_pcie->pp.dev, ks_pcie->va_app_base))
+ return IRQ_HANDLED;
+
+ return IRQ_NONE;
+}
+
static int __init ks_add_pcie_port(struct keystone_pcie *ks_pcie,
struct platform_device *pdev)
{
@@ -309,6 +324,22 @@ static int __init ks_add_pcie_port(struct keystone_pcie *ks_pcie,
return ret;
}
+ /*
+ * index 0 is the platform interrupt for error interrupt
+ * from RC. As this is optional to define this, we will
+ * just print a warning
+ */
+ ks_pcie->error_irq = irq_of_parse_and_map(ks_pcie->np, 0);
+ if (ks_pcie->error_irq <= 0)
+ dev_warn(&pdev->dev, "No error irq defined\n");
+ else {
+ if (request_irq(ks_pcie->error_irq, pcie_err_irq_handler,
+ IRQF_SHARED, "pcie-error-irq", ks_pcie) < 0) {
+ dev_err(&pdev->dev, "failed to request error irq\n");
+ return ret;
+ }
+ }
+
pp->root_bus_nr = -1;
pp->ops = &keystone_pcie_host_ops;
ret = ks_dw_pcie_host_init(ks_pcie, ks_pcie->msi_intc_np);
@@ -376,6 +407,7 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
devm_release_mem_region(dev, res->start, resource_size(res));
pp->dev = dev;
+ ks_pcie->np = node;
platform_set_drvdata(pdev, ks_pcie);
ks_pcie->clk = devm_clk_get(dev, "pcie");
if (IS_ERR(ks_pcie->clk)) {
diff --git a/drivers/pci/host/pci-keystone.h b/drivers/pci/host/pci-keystone.h
index f0944e8..2daa215 100644
--- a/drivers/pci/host/pci-keystone.h
+++ b/drivers/pci/host/pci-keystone.h
@@ -29,6 +29,10 @@ struct keystone_pcie {
int msi_host_irqs[MAX_MSI_HOST_IRQS];
struct device_node *msi_intc_np;
struct irq_domain *legacy_irq_domain;
+ struct device_node *np;
+
+ /* error interrupt */
+ int error_irq;
/* Application register space */
void __iomem *va_app_base;
@@ -42,6 +46,8 @@ phys_addr_t ks_dw_pcie_get_msi_addr(struct pcie_port *pp);
/* Keystone specific PCI controller APIs */
void ks_dw_pcie_enable_legacy_irqs(struct keystone_pcie *ks_pcie);
void ks_dw_pcie_handle_legacy_irq(struct keystone_pcie *ks_pcie, int offset);
+void ks_dw_pcie_enable_error_irq(void __iomem *reg_base);
+bool ks_dw_pcie_handle_error_irq(struct device *dev, void __iomem *reg_base);
int ks_dw_pcie_host_init(struct keystone_pcie *ks_pcie,
struct device_node *msi_intc_np);
int ks_dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
--
1.9.1