- Adding support for versal CPM as Root port.
- The Versal ACAP devices include CCIX-PCIe Module (CPM). The integrated
block for CPM along with the integrated bridge can function
as PCIe Root Port.
- Versal CPM uses GICv3 ITS feature for assigning MSI/MSI-X
vectors and handling MSI/MSI-X interrupts.
- Bridge error and legacy interrupts in versal CPM are handled using
versal CPM specific MISC interrupt line.
Bharat Kumar Gogada (2):
PCI: Versal CPM: Add device tree binding forversal CPM host controller
PCI: Versal CPM: Add support for Versal CPM Root Port driver
.../devicetree/bindings/pci/xilinx-versal-cpm.txt | 66 +++
drivers/pci/controller/Kconfig | 8 +
drivers/pci/controller/Makefile | 1 +
drivers/pci/controller/pcie-xilinx-cpm.c | 511 +++++++++++++++++++++
4 files changed, 586 insertions(+)
create mode 100644 Documentation/devicetree/bindings/pci/xilinx-versal-cpm.txt
create mode 100644 drivers/pci/controller/pcie-xilinx-cpm.c
--
2.7.4
- Adding support for versal CPM as Root Port.
- The Versal ACAP devices include CCIX-PCIe Module (CPM). The integrated
block for CPM along with the integrated bridge can function
as PCIe Root Port.
- Versal CPM uses GICv3 ITS feature for assigning MSI/MSI-X
vectors and handling MSI/MSI-X interrupts.
- Bridge error and legacy interrupts in versal CPM are handled using
versal CPM specific MISC interrupt line.
Signed-off-by: Bharat Kumar Gogada <[email protected]>
---
drivers/pci/controller/Kconfig | 8 +
drivers/pci/controller/Makefile | 1 +
drivers/pci/controller/pcie-xilinx-cpm.c | 511 +++++++++++++++++++++++++++++++
3 files changed, 520 insertions(+)
create mode 100644 drivers/pci/controller/pcie-xilinx-cpm.c
diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index c77069c..eca496d 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -81,6 +81,14 @@ config PCIE_XILINX
Say 'Y' here if you want kernel to support the Xilinx AXI PCIe
Host Bridge driver.
+config PCIE_XILINX_CPM
+ bool "Xilinx Versal CPM host bridge support"
+ depends on ARCH_ZYNQMP || COMPILE_TEST
+ help
+ Say 'Y' here if you want kernel to enable support the
+ Xilinx Versal CPM host Bridge driver.The driver supports
+ MSI/MSI-X interrupts using GICv3 ITS feature.
+
config PCI_XGENE
bool "X-Gene PCIe controller"
depends on ARM64 || COMPILE_TEST
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index 3d4f597..6c936e9 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_PCI_HOST_COMMON) += pci-host-common.o
obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
obj-$(CONFIG_PCIE_XILINX) += pcie-xilinx.o
obj-$(CONFIG_PCIE_XILINX_NWL) += pcie-xilinx-nwl.o
+obj-$(CONFIG_PCIE_XILINX_CPM) += pcie-xilinx-cpm.o
obj-$(CONFIG_PCI_V3_SEMI) += pci-v3-semi.o
obj-$(CONFIG_PCI_XGENE_MSI) += pci-xgene-msi.o
obj-$(CONFIG_PCI_VERSATILE) += pci-versatile.o
diff --git a/drivers/pci/controller/pcie-xilinx-cpm.c b/drivers/pci/controller/pcie-xilinx-cpm.c
new file mode 100644
index 0000000..9c0852a
--- /dev/null
+++ b/drivers/pci/controller/pcie-xilinx-cpm.c
@@ -0,0 +1,511 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * PCIe host controller driver for Xilinx Versal CPM DMA Bridge
+ *
+ * (C) Copyright 2019 - 2020, Xilinx, Inc.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/of_irq.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+
+#include "../pci.h"
+
+/* Register definitions */
+#define XILINX_CPM_PCIE_REG_IDR 0x00000E10
+#define XILINX_CPM_PCIE_REG_IMR 0x00000E14
+#define XILINX_CPM_PCIE_REG_PSCR 0x00000E1C
+#define XILINX_CPM_PCIE_REG_RPSC 0x00000E20
+#define XILINX_CPM_PCIE_REG_RPEFR 0x00000E2C
+#define XILINX_CPM_PCIE_REG_IDRN 0x00000E38
+#define XILINX_CPM_PCIE_REG_IDRN_MASK 0x00000E3C
+#define XILINX_CPM_PCIE_MISC_IR_STATUS 0x00000340
+#define XILINX_CPM_PCIE_MISC_IR_ENABLE 0x00000348
+#define XILINX_CPM_PCIE_MISC_IR_LOCAL BIT(1)
+
+/* Interrupt registers definitions */
+#define XILINX_CPM_PCIE_INTR_LINK_DOWN BIT(0)
+#define XILINX_CPM_PCIE_INTR_HOT_RESET BIT(3)
+#define XILINX_CPM_PCIE_INTR_CFG_TIMEOUT BIT(8)
+#define XILINX_CPM_PCIE_INTR_CORRECTABLE BIT(9)
+#define XILINX_CPM_PCIE_INTR_NONFATAL BIT(10)
+#define XILINX_CPM_PCIE_INTR_FATAL BIT(11)
+#define XILINX_CPM_PCIE_INTR_INTX BIT(16)
+#define XILINX_CPM_PCIE_INTR_MSI BIT(17)
+#define XILINX_CPM_PCIE_INTR_SLV_UNSUPP BIT(20)
+#define XILINX_CPM_PCIE_INTR_SLV_UNEXP BIT(21)
+#define XILINX_CPM_PCIE_INTR_SLV_COMPL BIT(22)
+#define XILINX_CPM_PCIE_INTR_SLV_ERRP BIT(23)
+#define XILINX_CPM_PCIE_INTR_SLV_CMPABT BIT(24)
+#define XILINX_CPM_PCIE_INTR_SLV_ILLBUR BIT(25)
+#define XILINX_CPM_PCIE_INTR_MST_DECERR BIT(26)
+#define XILINX_CPM_PCIE_INTR_MST_SLVERR BIT(27)
+#define XILINX_CPM_PCIE_IMR_ALL_MASK 0x1FF39FF9
+#define XILINX_CPM_PCIE_IDR_ALL_MASK 0xFFFFFFFF
+#define XILINX_CPM_PCIE_IDRN_MASK GENMASK(19, 16)
+#define XILINX_CPM_PCIE_INTR_CFG_PCIE_TIMEOUT BIT(4)
+#define XILINX_CPM_PCIE_INTR_CFG_ERR_POISON BIT(12)
+#define XILINX_CPM_PCIE_INTR_PME_TO_ACK_RCVD BIT(15)
+#define XILINX_CPM_PCIE_INTR_PM_PME_RCVD BIT(17)
+#define XILINX_CPM_PCIE_INTR_SLV_PCIE_TIMEOUT BIT(28)
+#define XILINX_CPM_PCIE_IDRN_SHIFT 16
+
+/* Root Port Error FIFO Read Register definitions */
+#define XILINX_CPM_PCIE_RPEFR_ERR_VALID BIT(18)
+#define XILINX_CPM_PCIE_RPEFR_REQ_ID GENMASK(15, 0)
+#define XILINX_CPM_PCIE_RPEFR_ALL_MASK 0xFFFFFFFF
+
+/* Root Port Status/control Register definitions */
+#define XILINX_CPM_PCIE_REG_RPSC_BEN BIT(0)
+
+/* Phy Status/Control Register definitions */
+#define XILINX_CPM_PCIE_REG_PSCR_LNKUP BIT(11)
+
+/* ECAM definitions */
+#define ECAM_BUS_NUM_SHIFT 20
+#define ECAM_DEV_NUM_SHIFT 12
+
+#define INTX_NUM 4
+
+/**
+ * struct xilinx_cpm_pcie_port - PCIe port information
+ * @reg_base: Bridge Register Base
+ * @cpm_base: CPM SLCR Register Base
+ * @irq: Interrupt number
+ * @root_busno: Root Bus number
+ * @dev: Device pointer
+ * @leg_domain: Legacy IRQ domain pointer
+ * @irq_misc: Legacy and error interrupt number
+ */
+struct xilinx_cpm_pcie_port {
+ void __iomem *reg_base;
+ void __iomem *cpm_base;
+ u32 irq;
+ u8 root_busno;
+ struct device *dev;
+ struct irq_domain *leg_domain;
+ int irq_misc;
+};
+
+static inline u32 pcie_read(struct xilinx_cpm_pcie_port *port, u32 reg)
+{
+ return readl(port->reg_base + reg);
+}
+
+static inline void pcie_write(struct xilinx_cpm_pcie_port *port,
+ u32 val, u32 reg)
+{
+ writel(val, port->reg_base + reg);
+}
+
+static inline bool cpm_pcie_link_is_up(struct xilinx_cpm_pcie_port *port)
+{
+ return (pcie_read(port, XILINX_CPM_PCIE_REG_PSCR) &
+ XILINX_CPM_PCIE_REG_PSCR_LNKUP) ? 1 : 0;
+}
+
+/**
+ * xilinx_cpm_pcie_clear_err_interrupts - Clear Error Interrupts
+ * @port: PCIe port information
+ */
+static void cpm_pcie_clear_err_interrupts(struct xilinx_cpm_pcie_port *port)
+{
+ unsigned long val = pcie_read(port, XILINX_CPM_PCIE_REG_RPEFR);
+
+ if (val & XILINX_CPM_PCIE_RPEFR_ERR_VALID) {
+ dev_dbg(port->dev, "Requester ID %lu\n",
+ val & XILINX_CPM_PCIE_RPEFR_REQ_ID);
+ pcie_write(port, XILINX_CPM_PCIE_RPEFR_ALL_MASK,
+ XILINX_CPM_PCIE_REG_RPEFR);
+ }
+}
+
+/**
+ * xilinx_cpm_pcie_valid_device - Check if a valid device is present on bus
+ * @bus: PCI Bus structure
+ * @devfn: device/function
+ *
+ * Return: 'true' on success and 'false' if invalid device is found
+ */
+static bool xilinx_cpm_pcie_valid_device(struct pci_bus *bus,
+ unsigned int devfn)
+{
+ struct xilinx_cpm_pcie_port *port = bus->sysdata;
+
+ /* Check if link is up when trying to access downstream ports */
+ if (bus->number != port->root_busno)
+ if (!cpm_pcie_link_is_up(port))
+ return false;
+
+ /* Only one device down on each root port */
+ if (bus->number == port->root_busno && devfn > 0)
+ return false;
+
+ return true;
+}
+
+/**
+ * xilinx_cpm_pcie_map_bus - Get configuration base
+ * @bus: PCI Bus structure
+ * @devfn: Device/function
+ * @where: Offset from base
+ *
+ * Return: Base address of the configuration space needed to be
+ * accessed.
+ */
+static void __iomem *xilinx_cpm_pcie_map_bus(struct pci_bus *bus,
+ unsigned int devfn, int where)
+{
+ struct xilinx_cpm_pcie_port *port = bus->sysdata;
+ int relbus;
+
+ if (!xilinx_cpm_pcie_valid_device(bus, devfn))
+ return NULL;
+
+ relbus = (bus->number << ECAM_BUS_NUM_SHIFT) |
+ (devfn << ECAM_DEV_NUM_SHIFT);
+
+ return port->reg_base + relbus + where;
+}
+
+/* PCIe operations */
+static struct pci_ops xilinx_cpm_pcie_ops = {
+ .map_bus = xilinx_cpm_pcie_map_bus,
+ .read = pci_generic_config_read,
+ .write = pci_generic_config_write,
+};
+
+/**
+ * xilinx_cpm_pcie_intx_map - Set the handler for the INTx and mark IRQ as valid
+ * @domain: IRQ domain
+ * @irq: Virtual IRQ number
+ * @hwirq: HW interrupt number
+ *
+ * Return: Always returns 0.
+ */
+static int xilinx_cpm_pcie_intx_map(struct irq_domain *domain,
+ unsigned int irq, irq_hw_number_t hwirq)
+{
+ irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
+ irq_set_chip_data(irq, domain->host_data);
+ irq_set_status_flags(irq, IRQ_LEVEL);
+
+ return 0;
+}
+
+/* INTx IRQ Domain operations */
+static const struct irq_domain_ops intx_domain_ops = {
+ .map = xilinx_cpm_pcie_intx_map,
+ .xlate = pci_irqd_intx_xlate,
+};
+
+/**
+ * xilinx_cpm_pcie_intr_handler - Interrupt Service Handler
+ * @irq: IRQ number
+ * @data: PCIe port information
+ *
+ * Return: IRQ_HANDLED on success and IRQ_NONE on failure
+ */
+static irqreturn_t xilinx_cpm_pcie_intr_handler(int irq, void *data)
+{
+ struct xilinx_cpm_pcie_port *port =
+ (struct xilinx_cpm_pcie_port *)data;
+ u32 val, mask, status, bit;
+ unsigned long intr_val;
+
+ /* Read interrupt decode and mask registers */
+ val = pcie_read(port, XILINX_CPM_PCIE_REG_IDR);
+ mask = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
+
+ status = val & mask;
+ if (!status)
+ return IRQ_NONE;
+
+ if (status & XILINX_CPM_PCIE_INTR_LINK_DOWN)
+ dev_warn(port->dev, "Link Down\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_HOT_RESET)
+ dev_info(port->dev, "Hot reset\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_CFG_TIMEOUT)
+ dev_warn(port->dev, "ECAM access timeout\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_CORRECTABLE) {
+ dev_warn(port->dev, "Correctable error message\n");
+ cpm_pcie_clear_err_interrupts(port);
+ }
+
+ if (status & XILINX_CPM_PCIE_INTR_NONFATAL) {
+ dev_warn(port->dev, "Non fatal error message\n");
+ cpm_pcie_clear_err_interrupts(port);
+ }
+
+ if (status & XILINX_CPM_PCIE_INTR_FATAL) {
+ dev_warn(port->dev, "Fatal error message\n");
+ cpm_pcie_clear_err_interrupts(port);
+ }
+
+ if (status & XILINX_CPM_PCIE_INTR_INTX) {
+ /* Handle INTx Interrupt */
+ intr_val = pcie_read(port, XILINX_CPM_PCIE_REG_IDRN);
+ intr_val = intr_val >> XILINX_CPM_PCIE_IDRN_SHIFT;
+
+ for_each_set_bit(bit, &intr_val, INTX_NUM)
+ generic_handle_irq(irq_find_mapping(port->leg_domain,
+ bit));
+ }
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_UNSUPP)
+ dev_warn(port->dev, "Slave unsupported request\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_UNEXP)
+ dev_warn(port->dev, "Slave unexpected completion\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_COMPL)
+ dev_warn(port->dev, "Slave completion timeout\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_ERRP)
+ dev_warn(port->dev, "Slave Error Poison\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_CMPABT)
+ dev_warn(port->dev, "Slave Completer Abort\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_ILLBUR)
+ dev_warn(port->dev, "Slave Illegal Burst\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_MST_DECERR)
+ dev_warn(port->dev, "Master decode error\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_MST_SLVERR)
+ dev_warn(port->dev, "Master slave error\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_CFG_PCIE_TIMEOUT)
+ dev_warn(port->dev, "PCIe ECAM access timeout\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_CFG_ERR_POISON)
+ dev_warn(port->dev, "ECAM poisoned completion received\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_PME_TO_ACK_RCVD)
+ dev_warn(port->dev, "PME_TO_ACK message received\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_PM_PME_RCVD)
+ dev_warn(port->dev, "PM_PME message received\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_PCIE_TIMEOUT)
+ dev_warn(port->dev, "PCIe completion timeout received\n");
+
+ /* Clear the Interrupt Decode register */
+ pcie_write(port, status, XILINX_CPM_PCIE_REG_IDR);
+ val = readl(port->cpm_base + XILINX_CPM_PCIE_MISC_IR_STATUS);
+ if (val)
+ writel(val, port->cpm_base + XILINX_CPM_PCIE_MISC_IR_STATUS);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * xilinx_cpm_pcie_init_irq_domain - Initialize IRQ domain
+ * @port: PCIe port information
+ *
+ * Return: '0' on success and error value on failure
+ */
+static int xilinx_cpm_pcie_init_irq_domain(struct xilinx_cpm_pcie_port *port)
+{
+ struct device *dev = port->dev;
+ struct device_node *node = dev->of_node;
+ struct device_node *pcie_intc_node;
+
+ /* Setup INTx */
+ pcie_intc_node = of_get_next_child(node, NULL);
+ if (!pcie_intc_node) {
+ dev_err(dev, "No PCIe Intc node found\n");
+ return PTR_ERR(pcie_intc_node);
+ }
+
+ port->leg_domain = irq_domain_add_linear(pcie_intc_node, INTX_NUM,
+ &intx_domain_ops,
+ port);
+ if (!port->leg_domain) {
+ dev_err(dev, "Failed to get a INTx IRQ domain\n");
+ return PTR_ERR(port->leg_domain);
+ }
+
+ return 0;
+}
+
+/**
+ * xilinx_cpm_pcie_init_port - Initialize hardware
+ * @port: PCIe port information
+ */
+static void xilinx_cpm_pcie_init_port(struct xilinx_cpm_pcie_port *port)
+{
+ if (cpm_pcie_link_is_up(port))
+ dev_info(port->dev, "PCIe Link is UP\n");
+ else
+ dev_info(port->dev, "PCIe Link is DOWN\n");
+
+ /* Disable all interrupts */
+ pcie_write(port, ~XILINX_CPM_PCIE_IDR_ALL_MASK,
+ XILINX_CPM_PCIE_REG_IMR);
+
+ /* Clear pending interrupts */
+ pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_IDR) &
+ XILINX_CPM_PCIE_IMR_ALL_MASK,
+ XILINX_CPM_PCIE_REG_IDR);
+
+ /* Enable all interrupts */
+ pcie_write(port, XILINX_CPM_PCIE_IMR_ALL_MASK,
+ XILINX_CPM_PCIE_REG_IMR);
+ pcie_write(port, XILINX_CPM_PCIE_IDRN_MASK,
+ XILINX_CPM_PCIE_REG_IDRN_MASK);
+
+ writel(XILINX_CPM_PCIE_MISC_IR_LOCAL,
+ port->cpm_base + XILINX_CPM_PCIE_MISC_IR_ENABLE);
+ /* Enable the Bridge enable bit */
+ pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_RPSC) |
+ XILINX_CPM_PCIE_REG_RPSC_BEN,
+ XILINX_CPM_PCIE_REG_RPSC);
+}
+
+static int xilinx_cpm_request_misc_irq(struct xilinx_cpm_pcie_port *port)
+{
+ struct device *dev = port->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ int err;
+
+ port->irq_misc = platform_get_irq_byname(pdev, "misc");
+ if (port->irq_misc <= 0) {
+ dev_err(dev, "Unable to find misc IRQ line\n");
+ return port->irq_misc;
+ }
+ err = devm_request_irq(dev, port->irq_misc,
+ xilinx_cpm_pcie_intr_handler,
+ IRQF_SHARED | IRQF_NO_THREAD,
+ "xilinx-pcie", port);
+ if (err) {
+ dev_err(dev, "unable to request misc IRQ line %d\n",
+ port->irq_misc);
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * xilinx_cpm_pcie_parse_dt - Parse Device tree
+ * @port: PCIe port information
+ *
+ * Return: '0' on success and error value on failure
+ */
+static int xilinx_cpm_pcie_parse_dt(struct xilinx_cpm_pcie_port *port)
+{
+ struct device *dev = port->dev;
+ struct resource *res;
+ int err;
+ struct platform_device *pdev = to_platform_device(dev);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
+ port->reg_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(port->reg_base))
+ return PTR_ERR(port->reg_base);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ "cpm_slcr");
+ port->cpm_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(port->cpm_base))
+ return PTR_ERR(port->cpm_base);
+
+ err = xilinx_cpm_request_misc_irq(port);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+/**
+ * xilinx_cpm_pcie_probe - Probe function
+ * @pdev: Platform device pointer
+ *
+ * Return: '0' on success and error value on failure
+ */
+static int xilinx_cpm_pcie_probe(struct platform_device *pdev)
+{
+ struct xilinx_cpm_pcie_port *port;
+ struct device *dev = &pdev->dev;
+ struct pci_bus *bus;
+ struct pci_bus *child;
+ struct pci_host_bridge *bridge;
+ int err;
+
+ bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port));
+ if (!bridge)
+ return -ENODEV;
+
+ port = pci_host_bridge_priv(bridge);
+
+ port->dev = dev;
+
+ err = xilinx_cpm_pcie_parse_dt(port);
+ if (err) {
+ dev_err(dev, "Parsing DT failed\n");
+ return err;
+ }
+
+ xilinx_cpm_pcie_init_port(port);
+
+ err = xilinx_cpm_pcie_init_irq_domain(port);
+ if (err) {
+ dev_err(dev, "Failed creating IRQ Domain\n");
+ return err;
+ }
+
+ err = pci_parse_request_of_pci_ranges(dev, &bridge->windows,
+ &bridge->dma_ranges, NULL);
+ if (err) {
+ dev_err(dev, "Getting bridge resources failed\n");
+ return err;
+ }
+
+ bridge->dev.parent = dev;
+ bridge->sysdata = port;
+ bridge->busnr = port->root_busno;
+ bridge->ops = &xilinx_cpm_pcie_ops;
+ bridge->map_irq = of_irq_parse_and_map_pci;
+ bridge->swizzle_irq = pci_common_swizzle;
+
+ err = pci_scan_root_bus_bridge(bridge);
+ if (err)
+ return err;
+
+ bus = bridge->bus;
+
+ pci_assign_unassigned_bus_resources(bus);
+ list_for_each_entry(child, &bus->children, node)
+ pcie_bus_configure_settings(child);
+ pci_bus_add_devices(bus);
+ return 0;
+}
+
+static const struct of_device_id xilinx_cpm_pcie_of_match[] = {
+ { .compatible = "xlnx,versal-cpm-host-1.00", },
+ {}
+};
+
+static struct platform_driver xilinx_cpm_pcie_driver = {
+ .driver = {
+ .name = "xilinx-cpm-pcie",
+ .of_match_table = xilinx_cpm_pcie_of_match,
+ .suppress_bind_attrs = true,
+ },
+ .probe = xilinx_cpm_pcie_probe,
+};
+
+builtin_platform_driver(xilinx_cpm_pcie_driver);
--
2.7.4
[+cc other drivers that use the broken "is link up" test in config
access]
On Fri, Dec 20, 2019 at 05:11:12PM +0530, Bharat Kumar Gogada wrote:
> - Adding support for versal CPM as Root Port.
> - The Versal ACAP devices include CCIX-PCIe Module (CPM). The integrated
> block for CPM along with the integrated bridge can function
> as PCIe Root Port.
> - Versal CPM uses GICv3 ITS feature for assigning MSI/MSI-X
> vectors and handling MSI/MSI-X interrupts.
> - Bridge error and legacy interrupts in versal CPM are handled using
> versal CPM specific MISC interrupt line.
"Versal" appears to be a brand name and should be capitalized
consistently.
> +#define INTX_NUM 4
Don't we have a generic PCI core definition for this?
> +static inline bool cpm_pcie_link_is_up(struct xilinx_cpm_pcie_port *port)
Please follow the example of other drivers and name this
"cpm_pcie_link_up()".
> +{
> + return (pcie_read(port, XILINX_CPM_PCIE_REG_PSCR) &
> + XILINX_CPM_PCIE_REG_PSCR_LNKUP) ? 1 : 0;
> +}
> +/**
> + * xilinx_cpm_pcie_valid_device - Check if a valid device is present on bus
> + * @bus: PCI Bus structure
> + * @devfn: device/function
> + *
> + * Return: 'true' on success and 'false' if invalid device is found
> + */
> +static bool xilinx_cpm_pcie_valid_device(struct pci_bus *bus,
> + unsigned int devfn)
> +{
> + struct xilinx_cpm_pcie_port *port = bus->sysdata;
> +
> + /* Check if link is up when trying to access downstream ports */
> + if (bus->number != port->root_busno)
> + if (!cpm_pcie_link_is_up(port))
> + return false;
This check for the link being up is racy and should be removed. The
link may go down after the check and before the config access.
A config access to a device where the link is down is an error, but
it's an error we expect to happen because of enumeration, surprise
unplug, or electrical issue. It's impossible to avoid so we must be
able to handle and recover from it.
I know there are other drivers that do this (dwc, altera, xilinix-nwl,
xilinx), and I've pointed this out many times in the past. This needs
to be fixed.
> +
> + /* Only one device down on each root port */
> + if (bus->number == port->root_busno && devfn > 0)
> + return false;
> +
> + return true;
> +}
> +static irqreturn_t xilinx_cpm_pcie_intr_handler(int irq, void *data)
> +{
> + struct xilinx_cpm_pcie_port *port =
> + (struct xilinx_cpm_pcie_port *)data;
struct device *dev = port->dev;
to reduce repetition of "port->dev" below.
> + u32 val, mask, status, bit;
> + unsigned long intr_val;
> +
> + /* Read interrupt decode and mask registers */
> + val = pcie_read(port, XILINX_CPM_PCIE_REG_IDR);
> + mask = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
> +
> + status = val & mask;
> + if (!status)
> + return IRQ_NONE;
> +
> + if (status & XILINX_CPM_PCIE_INTR_LINK_DOWN)
> + dev_warn(port->dev, "Link Down\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_HOT_RESET)
> + dev_info(port->dev, "Hot reset\n");
> ...
> Subject: Re: [PATCH 2/2] PCI: Versal CPM: Add support for Versal CPM Root Port
> driver
>
> [+cc other drivers that use the broken "is link up" test in config access]
>
> On Fri, Dec 20, 2019 at 05:11:12PM +0530, Bharat Kumar Gogada wrote:
> > - Adding support for versal CPM as Root Port.
> > - The Versal ACAP devices include CCIX-PCIe Module (CPM). The integrated
> > block for CPM along with the integrated bridge can function
> > as PCIe Root Port.
> > - Versal CPM uses GICv3 ITS feature for assigning MSI/MSI-X
> > vectors and handling MSI/MSI-X interrupts.
> > - Bridge error and legacy interrupts in versal CPM are handled using
> > versal CPM specific MISC interrupt line.
>
> "Versal" appears to be a brand name and should be capitalized consistently.
>
> > +#define INTX_NUM 4
>
> Don't we have a generic PCI core definition for this?
Thanks Bjorn, will fix this with core definition.
>
> > +static inline bool cpm_pcie_link_is_up(struct xilinx_cpm_pcie_port
> > +*port)
>
> Please follow the example of other drivers and name this "cpm_pcie_link_up()".
Agreed, will change the name.
>
> > +{
> > + return (pcie_read(port, XILINX_CPM_PCIE_REG_PSCR) &
> > + XILINX_CPM_PCIE_REG_PSCR_LNKUP) ? 1 : 0; }
>
> > +/**
> > + * xilinx_cpm_pcie_valid_device - Check if a valid device is present
> > +on bus
> > + * @bus: PCI Bus structure
> > + * @devfn: device/function
> > + *
> > + * Return: 'true' on success and 'false' if invalid device is found
> > +*/ static bool xilinx_cpm_pcie_valid_device(struct pci_bus *bus,
> > + unsigned int devfn)
> > +{
> > + struct xilinx_cpm_pcie_port *port = bus->sysdata;
> > +
> > + /* Check if link is up when trying to access downstream ports */
> > + if (bus->number != port->root_busno)
> > + if (!cpm_pcie_link_is_up(port))
> > + return false;
>
> This check for the link being up is racy and should be removed. The link may go
> down after the check and before the config access.
>
> A config access to a device where the link is down is an error, but it's an error we
> expect to happen because of enumeration, surprise unplug, or electrical issue.
> It's impossible to avoid so we must be able to handle and recover from it.
>
> I know there are other drivers that do this (dwc, altera, xilinix-nwl, xilinx), and
> I've pointed this out many times in the past. This needs to be fixed.
Agreed, will fix this check.
>
> > +
> > + /* Only one device down on each root port */
> > + if (bus->number == port->root_busno && devfn > 0)
> > + return false;
> > +
> > + return true;
> > +}
>
> > +static irqreturn_t xilinx_cpm_pcie_intr_handler(int irq, void *data)
> > +{
> > + struct xilinx_cpm_pcie_port *port =
> > + (struct xilinx_cpm_pcie_port *)data;
>
> struct device *dev = port->dev;
>
> to reduce repetition of "port->dev" below.
Agreed, will fix this.
> > + u32 val, mask, status, bit;
> > + unsigned long intr_val;
> > +
> > + /* Read interrupt decode and mask registers */
> > + val = pcie_read(port, XILINX_CPM_PCIE_REG_IDR);
> > + mask = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
> > +
> > + status = val & mask;
> > + if (!status)
> > + return IRQ_NONE;
> > +
> > + if (status & XILINX_CPM_PCIE_INTR_LINK_DOWN)
> > + dev_warn(port->dev, "Link Down\n");
> > +
> > + if (status & XILINX_CPM_PCIE_INTR_HOT_RESET)
> > + dev_info(port->dev, "Hot reset\n");
> > ...
Hi Bharat,
Thank you for the patch! Perhaps something to improve:
url: https://github.com/0day-ci/linux/commits/Bharat-Kumar-Gogada/Adding-support-for-versal-CPM-as-Root-Port-driver/20191223-193219
base: https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
New smatch warnings:
drivers/pci/controller/pcie-xilinx-cpm.c:330 xilinx_cpm_pcie_init_irq_domain() warn: passing zero to 'PTR_ERR'
Old smatch warnings:
drivers/pci/controller/pcie-xilinx-cpm.c:338 xilinx_cpm_pcie_init_irq_domain() warn: passing zero to 'PTR_ERR'
# https://github.com/0day-ci/linux/commit/f107713acb796e598f16a23b33af74fa382921b2
git remote add linux-review https://github.com/0day-ci/linux
git remote update linux-review
git checkout f107713acb796e598f16a23b33af74fa382921b2
vim +/PTR_ERR +330 drivers/pci/controller/pcie-xilinx-cpm.c
f107713acb796e Bharat Kumar Gogada 2019-12-20 320 static int xilinx_cpm_pcie_init_irq_domain(struct xilinx_cpm_pcie_port *port)
f107713acb796e Bharat Kumar Gogada 2019-12-20 321 {
f107713acb796e Bharat Kumar Gogada 2019-12-20 322 struct device *dev = port->dev;
f107713acb796e Bharat Kumar Gogada 2019-12-20 323 struct device_node *node = dev->of_node;
f107713acb796e Bharat Kumar Gogada 2019-12-20 324 struct device_node *pcie_intc_node;
f107713acb796e Bharat Kumar Gogada 2019-12-20 325
f107713acb796e Bharat Kumar Gogada 2019-12-20 326 /* Setup INTx */
f107713acb796e Bharat Kumar Gogada 2019-12-20 327 pcie_intc_node = of_get_next_child(node, NULL);
f107713acb796e Bharat Kumar Gogada 2019-12-20 328 if (!pcie_intc_node) {
^^^^^^^^^^^^^^^
f107713acb796e Bharat Kumar Gogada 2019-12-20 329 dev_err(dev, "No PCIe Intc node found\n");
f107713acb796e Bharat Kumar Gogada 2019-12-20 @330 return PTR_ERR(pcie_intc_node);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
(This means success).
f107713acb796e Bharat Kumar Gogada 2019-12-20 331 }
f107713acb796e Bharat Kumar Gogada 2019-12-20 332
f107713acb796e Bharat Kumar Gogada 2019-12-20 333 port->leg_domain = irq_domain_add_linear(pcie_intc_node, INTX_NUM,
f107713acb796e Bharat Kumar Gogada 2019-12-20 334 &intx_domain_ops,
f107713acb796e Bharat Kumar Gogada 2019-12-20 335 port);
f107713acb796e Bharat Kumar Gogada 2019-12-20 336 if (!port->leg_domain) {
f107713acb796e Bharat Kumar Gogada 2019-12-20 337 dev_err(dev, "Failed to get a INTx IRQ domain\n");
f107713acb796e Bharat Kumar Gogada 2019-12-20 338 return PTR_ERR(port->leg_domain);
f107713acb796e Bharat Kumar Gogada 2019-12-20 339 }
f107713acb796e Bharat Kumar Gogada 2019-12-20 340
f107713acb796e Bharat Kumar Gogada 2019-12-20 341 return 0;
f107713acb796e Bharat Kumar Gogada 2019-12-20 342 }
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/hyperkitty/list/[email protected] Intel Corporation
Thanks Dan, will fix it and resend.
> -----Original Message-----
> From: Dan Carpenter <[email protected]>
> Sent: Monday, January 6, 2020 12:20 AM
> To: [email protected]; Bharat Kumar Gogada <[email protected]>
> Cc: [email protected]; [email protected]; linux-
> [email protected]; [email protected]; Ravikiran Gummaluri
> <[email protected]>; Bharat Kumar Gogada <[email protected]>
> Subject: Re: [PATCH 2/2] PCI: Versal CPM: Add support for Versal CPM Root Port
> driver
>
> Hi Bharat,
>
> Thank you for the patch! Perhaps something to improve:
>
> url: https://github.com/0day-ci/linux/commits/Bharat-Kumar-Gogada/Adding-
> support-for-versal-CPM-as-Root-Port-driver/20191223-193219
> base: https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
>
> If you fix the issue, kindly add following tag
> Reported-by: kbuild test robot <[email protected]>
> Reported-by: Dan Carpenter <[email protected]>
>
> New smatch warnings:
> drivers/pci/controller/pcie-xilinx-cpm.c:330 xilinx_cpm_pcie_init_irq_domain()
> warn: passing zero to 'PTR_ERR'
>
> Old smatch warnings:
> drivers/pci/controller/pcie-xilinx-cpm.c:338 xilinx_cpm_pcie_init_irq_domain()
> warn: passing zero to 'PTR_ERR'
>
> # https://github.com/0day-
> ci/linux/commit/f107713acb796e598f16a23b33af74fa382921b2
> git remote add linux-review https://github.com/0day-ci/linux
> git remote update linux-review
> git checkout f107713acb796e598f16a23b33af74fa382921b2
> vim +/PTR_ERR +330 drivers/pci/controller/pcie-xilinx-cpm.c
>
> f107713acb796e Bharat Kumar Gogada 2019-12-20 320 static int
> xilinx_cpm_pcie_init_irq_domain(struct xilinx_cpm_pcie_port *port)
> f107713acb796e Bharat Kumar Gogada 2019-12-20 321 {
> f107713acb796e Bharat Kumar Gogada 2019-12-20 322 struct device *dev =
> port->dev;
> f107713acb796e Bharat Kumar Gogada 2019-12-20 323 struct device_node
> *node = dev->of_node;
> f107713acb796e Bharat Kumar Gogada 2019-12-20 324 struct device_node
> *pcie_intc_node;
> f107713acb796e Bharat Kumar Gogada 2019-12-20 325
> f107713acb796e Bharat Kumar Gogada 2019-12-20 326 /* Setup INTx */
> f107713acb796e Bharat Kumar Gogada 2019-12-20 327 pcie_intc_node =
> of_get_next_child(node, NULL);
> f107713acb796e Bharat Kumar Gogada 2019-12-20 328 if (!pcie_intc_node) {
> ^^^^^^^^^^^^^^^
>
> f107713acb796e Bharat Kumar Gogada 2019-12-20 329 dev_err(dev,
> "No PCIe Intc node found\n");
> f107713acb796e Bharat Kumar Gogada 2019-12-20 @330 return
> PTR_ERR(pcie_intc_node);
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> (This means success).
>
> f107713acb796e Bharat Kumar Gogada 2019-12-20 331 }
> f107713acb796e Bharat Kumar Gogada 2019-12-20 332
> f107713acb796e Bharat Kumar Gogada 2019-12-20 333 port->leg_domain =
> irq_domain_add_linear(pcie_intc_node, INTX_NUM,
> f107713acb796e Bharat Kumar Gogada 2019-12-20 334
> &intx_domain_ops,
> f107713acb796e Bharat Kumar Gogada 2019-12-20 335
> port);
> f107713acb796e Bharat Kumar Gogada 2019-12-20 336 if (!port->leg_domain)
> {
> f107713acb796e Bharat Kumar Gogada 2019-12-20 337 dev_err(dev,
> "Failed to get a INTx IRQ domain\n");
> f107713acb796e Bharat Kumar Gogada 2019-12-20 338 return
> PTR_ERR(port->leg_domain);
> f107713acb796e Bharat Kumar Gogada 2019-12-20 339 }
> f107713acb796e Bharat Kumar Gogada 2019-12-20 340
> f107713acb796e Bharat Kumar Gogada 2019-12-20 341 return 0;
> f107713acb796e Bharat Kumar Gogada 2019-12-20 342 }
>
> ---
> 0-DAY kernel test infrastructure Open Source Technology Center
> https://lists.01.org/hyperkitty/list/[email protected] Intel Corporation