2020-01-28 12:46:15

by Bharat Kumar Gogada

[permalink] [raw]
Subject: [PATCH v4 0/2] Adding support for Versal CPM as Root Port driver.

- Add 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: xilinx-cpm: Add device tree binding for Versal CPM host bridge.
PCI: xilinx-cpm: Add 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 | 506 +++++++++++++++++++++
4 files changed, 581 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


2020-01-28 12:46:43

by Bharat Kumar Gogada

[permalink] [raw]
Subject: [PATCH v4 2/2] PCI: xilinx-cpm: Add Versal CPM Root Port driver

- Add 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.
- CPM Versal uses GICv3 ITS feature for achieving 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.

Changes v4:
- change commit subject.
- Remove unnecessary comments and type cast.
- Added comments for CPM block register access using readl/writel.

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 | 506 +++++++++++++++++++++++++++++++
3 files changed, 515 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..362f4db 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 support for the
+ Xilinx Versal CPM host bridge. 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..49ec5c7
--- /dev/null
+++ b/drivers/pci/controller/pcie-xilinx-cpm.c
@@ -0,0 +1,506 @@
+// 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
+
+/**
+ * struct xilinx_cpm_pcie_port - PCIe port information
+ * @reg_base: Bridge Register Base
+ * @cpm_base: CPM System Level Control and Status Register(SLCR) 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_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);
+ }
+}
+
+static bool xilinx_cpm_pcie_valid_device(struct pci_bus *bus,
+ unsigned int devfn)
+{
+ struct xilinx_cpm_pcie_port *port = bus->sysdata;
+
+ /* 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 = data;
+ struct device *dev = port->dev;
+ 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(dev, "Link Down\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_HOT_RESET)
+ dev_info(dev, "Hot reset\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_CFG_TIMEOUT)
+ dev_warn(dev, "ECAM access timeout\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_CORRECTABLE) {
+ dev_warn(dev, "Correctable error message\n");
+ cpm_pcie_clear_err_interrupts(port);
+ }
+
+ if (status & XILINX_CPM_PCIE_INTR_NONFATAL) {
+ dev_warn(dev, "Non fatal error message\n");
+ cpm_pcie_clear_err_interrupts(port);
+ }
+
+ if (status & XILINX_CPM_PCIE_INTR_FATAL) {
+ dev_warn(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, PCI_NUM_INTX)
+ generic_handle_irq(irq_find_mapping(port->leg_domain,
+ bit));
+ }
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_UNSUPP)
+ dev_warn(dev, "Slave unsupported request\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_UNEXP)
+ dev_warn(dev, "Slave unexpected completion\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_COMPL)
+ dev_warn(dev, "Slave completion timeout\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_ERRP)
+ dev_warn(dev, "Slave Error Poison\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_CMPABT)
+ dev_warn(dev, "Slave Completer Abort\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_ILLBUR)
+ dev_warn(dev, "Slave Illegal Burst\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_MST_DECERR)
+ dev_warn(dev, "Master decode error\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_MST_SLVERR)
+ dev_warn(dev, "Master slave error\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_CFG_PCIE_TIMEOUT)
+ dev_warn(dev, "PCIe ECAM access timeout\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_CFG_ERR_POISON)
+ dev_warn(dev, "ECAM poisoned completion received\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_PME_TO_ACK_RCVD)
+ dev_warn(dev, "PME_TO_ACK message received\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_PM_PME_RCVD)
+ dev_warn(dev, "PM_PME message received\n");
+
+ if (status & XILINX_CPM_PCIE_INTR_SLV_PCIE_TIMEOUT)
+ dev_warn(dev, "PCIe completion timeout received\n");
+
+ /* Clear the Interrupt Decode register */
+ pcie_write(port, status, XILINX_CPM_PCIE_REG_IDR);
+
+ /*
+ * XILINX_CPM_PCIE_MISC_IR_STATUS register is mapped to
+ * CPM SLCR block.
+ */
+ 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 -EINVAL;
+ }
+
+ port->leg_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
+ &intx_domain_ops,
+ port);
+ if (!port->leg_domain) {
+ dev_err(dev, "Failed to get a INTx IRQ domain\n");
+ return -ENOMEM;
+ }
+
+ 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_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);
+
+ /*
+ * XILINX_CPM_PCIE_MISC_IR_ENABLE register is mapped to
+ * CPM SLCR block.
+ */
+ 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 platform_device *pdev = to_platform_device(dev);
+ struct resource *res;
+ int err;
+
+ 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

2020-01-28 12:47:16

by Bharat Kumar Gogada

[permalink] [raw]
Subject: [PATCH v4 1/2] PCI: xilinx-cpm: Add device tree binding for Versal CPM host bridge.

Add device tree binding documentation for Versal CPM Root Port driver.

Signed-off-by: Bharat Kumar Gogada <[email protected]>
---
.../devicetree/bindings/pci/xilinx-versal-cpm.txt | 66 ++++++++++++++++++++++
1 file changed, 66 insertions(+)
create mode 100644 Documentation/devicetree/bindings/pci/xilinx-versal-cpm.txt

diff --git a/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.txt b/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.txt
new file mode 100644
index 0000000..35f8556
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.txt
@@ -0,0 +1,66 @@
+* Xilinx Versal CPM DMA Root Port Bridge DT description
+
+Required properties:
+- #address-cells: Address representation for root ports, set to <3>
+- #size-cells: Size representation for root ports, set to <2>
+- #interrupt-cells: specifies the number of cells needed to encode an
+ interrupt source. The value must be 1.
+- compatible: Should contain "xlnx,versal-cpm-host-1.00"
+- reg: Should contain configuration space (includes bridge registers) and
+ CPM system level control and status registers, and length
+- reg-names: Must include the following entries:
+ "cfg": configuration space region and bridge registers
+ "cpm_slcr": CPM system level control and status registers
+- interrupts: Should contain AXI PCIe interrupt
+- interrupt-map-mask,
+ interrupt-map: standard PCI properties to define the mapping of the
+ PCI interface to interrupt numbers.
+- ranges: ranges for the PCI memory regions (I/O space region is not
+ supported by hardware)
+ Please refer to the standard PCI bus binding document for a more
+ detailed explanation
+- msi-map: Maps a Requester ID to an MSI controller and associated MSI
+ sideband data
+- interrupt-names: Must include the following entries:
+ "misc": interrupt asserted when legacy or error interrupt is received
+
+Interrupt controller child node
++++++++++++++++++++++++++++++++
+Required properties:
+- interrupt-controller: identifies the node as an interrupt controller
+- #address-cells: specifies the number of cells needed to encode an
+ address. The value must be 0.
+- #interrupt-cells: specifies the number of cells needed to encode an
+ interrupt source. The value must be 1.
+
+
+Refer to the following binding document for more detailed description on
+the use of 'msi-map':
+ Documentation/devicetree/bindings/pci/pci-msi.txt
+
+Example:
+ pci@fca10000 {
+ #address-cells = <3>;
+ #interrupt-cells = <1>;
+ #size-cells = <2>;
+ compatible = "xlnx,versal-cpm-host-1.00";
+ interrupt-map = <0 0 0 1 &pcie_intc_0 1>,
+ <0 0 0 2 &pcie_intc_0 2>,
+ <0 0 0 3 &pcie_intc_0 3>,
+ <0 0 0 4 &pcie_intc_0 4>;
+ interrupt-map-mask = <0 0 0 7>;
+ interrupt-parent = <&gic>;
+ interrupt-names = "misc";
+ interrupts = <0 72 4>;
+ ranges = <0x02000000 0x00000000 0xE0000000 0x0 0xE0000000 0x00000000 0x10000000>,
+ <0x43000000 0x00000080 0x00000000 0x00000080 0x00000000 0x00000000 0x80000000>;
+ msi-map = <0x0 &its_gic 0x0 0x10000>;
+ reg = <0x6 0x00000000 0x0 0x1000000>,
+ <0x0 0xFCA10000 0x0 0x1000>;
+ reg-names = "cfg", "cpm_slcr";
+ pcie_intc_0: pci-interrupt-controller {
+ #address-cells = <0>;
+ #interrupt-cells = <1>;
+ interrupt-controller ;
+ };
+ };
--
2.7.4

2020-01-28 14:09:45

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH v4 0/2] Adding support for Versal CPM as Root Port driver.

On Tue, Jan 28, 2020 at 06:14:41PM +0530, Bharat Kumar Gogada wrote:
> - Add 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: xilinx-cpm: Add device tree binding for Versal CPM host bridge.
> PCI: xilinx-cpm: Add Versal CPM Root Port driver

Nit for next time: Omit the period at the end of the subject. No need
to repost just for that.

> .../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 | 506 +++++++++++++++++++++
> 4 files changed, 581 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
>

2020-01-28 14:09:45

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH v4 2/2] PCI: xilinx-cpm: Add Versal CPM Root Port driver

On Tue, Jan 28, 2020 at 06:14:43PM +0530, Bharat Kumar Gogada wrote:
> - Add 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.
> - CPM Versal uses GICv3 ITS feature for achieving 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.
>
> Changes v4:
> - change commit subject.
> - Remove unnecessary comments and type cast.
> - Added comments for CPM block register access using readl/writel.
>
> Signed-off-by: Bharat Kumar Gogada <[email protected]>
> ...

> +static bool xilinx_cpm_pcie_valid_device(struct pci_bus *bus,
> + unsigned int devfn)
> +{
> + struct xilinx_cpm_pcie_port *port = bus->sysdata;
> +
> + /* Only one device down on each root port */
> + if (bus->number == port->root_busno && devfn > 0)
> + return false;

This whole *_valid_device() thing is a mess. We shouldn't need it at
all. But if we *do* need it, I don't think you should check the
entire devfn because that means you can't attach a multifunction
device.

Several other drivers with similar *_valid_device() implementations
check only PCI_SLOT():

dw_pcie_valid_device()
advk_pcie_valid_device()
pci_dw_valid_device()
altera_pcie_valid_device()
mobiveil_pcie_valid_device()
rockchip_pcie_valid_device()

Even checking just PCI_SLOT() is problematic because I think an ARI
device with more than 8 functions will not work correctly.

What exactly happens if you omit this function, i.e., if we just go
ahead and attempt config accesses when the device is not present? We
*should* get something like an Unsupported Request completion, and
that *should* be a recoverable error. Most hardware turns this error
into read data of 0xffffffff. The OS should be able to figure out
that there's no device there and continue with no ill effects.

> + 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,
> +};

2020-01-29 11:17:59

by Bharat Kumar Gogada

[permalink] [raw]
Subject: RE: [PATCH v4 2/2] PCI: xilinx-cpm: Add Versal CPM Root Port driver

> Subject: Re: [PATCH v4 2/2] PCI: xilinx-cpm: Add Versal CPM Root Port driver
>
> On Tue, Jan 28, 2020 at 06:14:43PM +0530, Bharat Kumar Gogada wrote:
> > - Add 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.
> > - CPM Versal uses GICv3 ITS feature for achieving 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.
> >
> > Changes v4:
> > - change commit subject.
> > - Remove unnecessary comments and type cast.
> > - Added comments for CPM block register access using readl/writel.
> >
> > Signed-off-by: Bharat Kumar Gogada <[email protected]>
> > ...
>
> > +static bool xilinx_cpm_pcie_valid_device(struct pci_bus *bus,
> > + unsigned int devfn)
> > +{
> > + struct xilinx_cpm_pcie_port *port = bus->sysdata;
> > +
> > + /* Only one device down on each root port */
> > + if (bus->number == port->root_busno && devfn > 0)
> > + return false;
>
> This whole *_valid_device() thing is a mess. We shouldn't need it at all. But if
> we *do* need it, I don't think you should check the entire devfn because that
> means you can't attach a multifunction device.
>
> Several other drivers with similar *_valid_device() implementations check only
> PCI_SLOT():
>
> dw_pcie_valid_device()
> advk_pcie_valid_device()
> pci_dw_valid_device()
> altera_pcie_valid_device()
> mobiveil_pcie_valid_device()
> rockchip_pcie_valid_device()
>
> Even checking just PCI_SLOT() is problematic because I think an ARI device with
> more than 8 functions will not work correctly.
>
> What exactly happens if you omit this function, i.e., if we just go ahead and
> attempt config accesses when the device is not present? We
> *should* get something like an Unsupported Request completion, and that
> *should* be a recoverable error. Most hardware turns this error into read data
> of 0xffffffff. The OS should be able to figure out that there's no device there
> and continue with no ill effects.
>
Thanks Bjorn. I did test and I do not see any issue without this.
Will resend patch with this change.
> > + 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,
> > +};

Regards,
bharat

2020-01-29 14:32:55

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH v4 2/2] PCI: xilinx-cpm: Add Versal CPM Root Port driver

On Wed, Jan 29, 2020 at 11:16:47AM +0000, Bharat Kumar Gogada wrote:
> > Subject: Re: [PATCH v4 2/2] PCI: xilinx-cpm: Add Versal CPM Root Port driver
> >
> > On Tue, Jan 28, 2020 at 06:14:43PM +0530, Bharat Kumar Gogada wrote:
> > > - Add 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.
> > > - CPM Versal uses GICv3 ITS feature for achieving 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.
> > >
> > > Changes v4:
> > > - change commit subject.
> > > - Remove unnecessary comments and type cast.
> > > - Added comments for CPM block register access using readl/writel.
> > >
> > > Signed-off-by: Bharat Kumar Gogada <[email protected]>
> > > ...
> >
> > > +static bool xilinx_cpm_pcie_valid_device(struct pci_bus *bus,
> > > + unsigned int devfn)
> > > +{
> > > + struct xilinx_cpm_pcie_port *port = bus->sysdata;
> > > +
> > > + /* Only one device down on each root port */
> > > + if (bus->number == port->root_busno && devfn > 0)
> > > + return false;
> >
> > This whole *_valid_device() thing is a mess. We shouldn't need it at all. But if
> > we *do* need it, I don't think you should check the entire devfn because that
> > means you can't attach a multifunction device.
> >
> > Several other drivers with similar *_valid_device() implementations check only
> > PCI_SLOT():
> >
> > dw_pcie_valid_device()
> > advk_pcie_valid_device()
> > pci_dw_valid_device()
> > altera_pcie_valid_device()
> > mobiveil_pcie_valid_device()
> > rockchip_pcie_valid_device()
> >
> > Even checking just PCI_SLOT() is problematic because I think an ARI device with
> > more than 8 functions will not work correctly.
> >
> > What exactly happens if you omit this function, i.e., if we just go ahead and
> > attempt config accesses when the device is not present? We
> > *should* get something like an Unsupported Request completion, and that
> > *should* be a recoverable error. Most hardware turns this error into read data
> > of 0xffffffff. The OS should be able to figure out that there's no device there
> > and continue with no ill effects.
> >
> Thanks Bjorn. I did test and I do not see any issue without this.
> Will resend patch with this change.

That's great, thanks for testing that! I wonder how many other
drivers could just drop that code.

Bjorn