[RFC v1 08/16] arm: mvebu: the core PCIe driver
Thomas Petazzoni
thomas.petazzoni at free-electrons.com
Fri Dec 7 17:04:31 EST 2012
This driver implements the hw_pci operations needed by the core ARM
PCI code to setup PCI devices and get their corresponding IRQs, and
the pci_ops operations that are used by the PCI core to read/write the
configuration space of PCI devices.
In addition, this driver enumerates the different PCIe slots, and for
those having a device plugged in, it allocates the necessary address
decoding windows, using the new armada_370_xp_alloc_pcie_window()
function from mach-mvebu/addr-map.c.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
---
.../devicetree/bindings/pci/armada-370-xp-pcie.txt | 136 +++++++++
arch/arm/mach-mvebu/Makefile | 1 +
arch/arm/mach-mvebu/pcie.c | 306 ++++++++++++++++++++
3 files changed, 443 insertions(+)
create mode 100644 Documentation/devicetree/bindings/pci/armada-370-xp-pcie.txt
create mode 100644 arch/arm/mach-mvebu/pcie.c
diff --git a/Documentation/devicetree/bindings/pci/armada-370-xp-pcie.txt b/Documentation/devicetree/bindings/pci/armada-370-xp-pcie.txt
new file mode 100644
index 0000000..daf0775
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/armada-370-xp-pcie.txt
@@ -0,0 +1,136 @@
+* Marvell Armada 370/XP PCIe interfaces
+
+Mandatory properties:
+- compatible: must be "marvell,armada-370-xp-pcie"
+- status: either "disabled" or "okay"
+- #address-cells, set to <1>
+- #size-cells, set to <1>
+- ranges: describes the association between the physical addresses of
+ the PCIe registers for each PCIe interface with "virtual" addresses
+ as seen by the sub-nodes. One entry per PCIe interface. Each entry
+ must have 3 values: the "virtual" address seen by the sub-nodes, the
+ real physical address of the PCIe registers, and the size.
+
+In addition, the Device Tree node must have sub-nodes describing each
+PCIe interface, having the following mandatory properties:
+- reg: the address and size of the PCIe registers (translated
+ addresses according to the ranges property of the parent)
+- interrupts: the interrupt number of this PCIe interface
+- clocks: the clock associated to this PCIe interface
+- marvell,pcie-port: the physical PCIe port number
+- status: either "disabled" or "okay"
+
+and the following optional properties:
+- marvell,pcie-lane: the physical PCIe lane number, for ports having
+ multiple lanes. If this property is not found, we assume that the
+ value is 0.
+
+Example:
+
+pcie-controller {
+ compatible = "marvell,armada-370-xp-pcie";
+ status = "disabled";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <0 0xd0040000 0x2000 /* port0x1_port0 */
+ 0x2000 0xd0042000 0x2000 /* port2x1_port0 */
+ 0x4000 0xd0044000 0x2000 /* port0x1_port1 */
+ 0x8000 0xd0048000 0x2000 /* port0x1_port2 */
+ 0xC000 0xd004C000 0x2000 /* port0x1_port3 */
+ 0x10000 0xd0080000 0x2000 /* port1x1_port0 */
+ 0x12000 0xd0082000 0x2000 /* port3x1_port0 */
+ 0x14000 0xd0084000 0x2000 /* port1x1_port1 */
+ 0x18000 0xd0088000 0x2000 /* port1x1_port2 */
+ 0x1C000 0xd008C000 0x2000 /* port1x1_port3 */>;
+
+ pcie0.0 at 0xd0040000 {
+ reg = <0x0 0x2000>;
+ interrupts = <58>;
+ clocks = <&gateclk 5>;
+ marvell,pcie-port = <0>;
+ marvell,pcie-lane = <0>;
+ status = "disabled";
+ };
+
+ pcie0.1 at 0xd0044000 {
+ reg = <0x4000 0x2000>;
+ interrupts = <59>;
+ clocks = <&gateclk 5>;
+ marvell,pcie-port = <0>;
+ marvell,pcie-lane = <1>;
+ status = "disabled";
+ };
+
+ pcie0.2 at 0xd0048000 {
+ reg = <0x8000 0x2000>;
+ interrupts = <60>;
+ clocks = <&gateclk 5>;
+ marvell,pcie-port = <0>;
+ marvell,pcie-lane = <2>;
+ status = "disabled";
+ };
+
+ pcie0.3 at 0xd004C000 {
+ reg = <0xC000 0x2000>;
+ interrupts = <61>;
+ clocks = <&gateclk 5>;
+ marvell,pcie-port = <0>;
+ marvell,pcie-lane = <3>;
+ status = "disabled";
+ };
+
+ pcie1.0 at 0xd0040000 {
+ reg = <0x10000 0x2000>;
+ interrupts = <62>;
+ clocks = <&gateclk 6>;
+ marvell,pcie-port = <1>;
+ marvell,pcie-lane = <0>;
+ status = "disabled";
+ };
+
+ pcie1.1 at 0xd0044000 {
+ reg = <0x14000 0x2000>;
+ interrupts = <63>;
+ clocks = <&gateclk 6>;
+ marvell,pcie-port = <1>;
+ marvell,pcie-lane = <1>;
+ status = "disabled";
+ };
+
+ pcie1.2 at 0xd0048000 {
+ reg = <0x18000 0x2000>;
+ interrupts = <64>;
+ clocks = <&gateclk 6>;
+ marvell,pcie-port = <1>;
+ marvell,pcie-lane = <2>;
+ status = "disabled";
+ };
+
+ pcie1.3 at 0xd004C000 {
+ reg = <0x1C000 0x2000>;
+ interrupts = <65>;
+ clocks = <&gateclk 6>;
+ marvell,pcie-port = <1>;
+ marvell,pcie-lane = <3>;
+ status = "disabled";
+ };
+
+ pcie2 at 0xd0042000 {
+ reg = <0x2000 0x2000>;
+ interrupts = <99>;
+ clocks = <&gateclk 7>;
+ marvell,pcie-port = <2>;
+ marvell,pcie-lane = <0>;
+ status = "disabled";
+ };
+
+ pcie3 at 0xd0082000 {
+ reg = <0x12000 0x2000>;
+ interrupts = <103>;
+ clocks = <&gateclk 8>;
+ marvell,pcie-port = <3>;
+ marvell,pcie-lane = <0>;
+ status = "disabled";
+ };
+};
+
diff --git a/arch/arm/mach-mvebu/Makefile b/arch/arm/mach-mvebu/Makefile
index 5dcb369..e458ede 100644
--- a/arch/arm/mach-mvebu/Makefile
+++ b/arch/arm/mach-mvebu/Makefile
@@ -5,3 +5,4 @@ obj-y += system-controller.o
obj-$(CONFIG_MACH_ARMADA_370_XP) += armada-370-xp.o irq-armada-370-xp.o addr-map.o coherency.o coherency_ll.o pmsu.o
obj-$(CONFIG_SMP) += platsmp.o headsmp.o
obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
+obj-$(CONFIG_PCI) += pcie.o
diff --git a/arch/arm/mach-mvebu/pcie.c b/arch/arm/mach-mvebu/pcie.c
new file mode 100644
index 0000000..d88f800
--- /dev/null
+++ b/arch/arm/mach-mvebu/pcie.c
@@ -0,0 +1,306 @@
+/*
+ * PCIe driver for Marvell Armada 370 and Armada XP SoCs
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <plat/pcie.h>
+#include "common.h"
+
+struct pcie_port {
+ u8 root_bus_nr;
+ void __iomem *base;
+ spinlock_t conf_lock;
+ int irq;
+ struct resource res;
+ int haslink;
+ u32 port;
+ u32 lane;
+ struct clk *clk;
+};
+
+static struct pcie_port *pcie_ports;
+
+static int pcie_valid_config(struct pcie_port *pp, int bus, int dev)
+{
+ /*
+ * Don't go out when trying to access --
+ * 1. nonexisting device on local bus
+ * 2. where there's no device connected (no link)
+ */
+ if (bus == pp->root_bus_nr && dev == 0)
+ return 1;
+
+ if (!orion_pcie_link_up(pp->base))
+ return 0;
+
+ if (bus == pp->root_bus_nr && dev != 1)
+ return 0;
+
+ return 1;
+}
+
+/*
+ * PCIe config cycles are done by programming the PCIE_CONF_ADDR register
+ * and then reading the PCIE_CONF_DATA register. Need to make sure these
+ * transactions are atomic.
+ */
+static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
+ int size, u32 *val)
+{
+ struct pci_sys_data *sys = bus->sysdata;
+ struct pcie_port *pp = sys->private_data;
+ unsigned long flags;
+ int ret;
+
+ if (pcie_valid_config(pp, bus->number, PCI_SLOT(devfn)) == 0) {
+ *val = 0xffffffff;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+
+ spin_lock_irqsave(&pp->conf_lock, flags);
+ ret = orion_pcie_rd_conf(pp->base, bus, devfn, where, size, val);
+ spin_unlock_irqrestore(&pp->conf_lock, flags);
+
+ return ret;
+}
+
+static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
+ int where, int size, u32 val)
+{
+ struct pci_sys_data *sys = bus->sysdata;
+ struct pcie_port *pp = sys->private_data;
+ unsigned long flags;
+ int ret;
+
+ if (pcie_valid_config(pp, bus->number, PCI_SLOT(devfn)) == 0)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ spin_lock_irqsave(&pp->conf_lock, flags);
+ ret = orion_pcie_wr_conf(pp->base, bus, devfn, where, size, val);
+ spin_unlock_irqrestore(&pp->conf_lock, flags);
+
+ return ret;
+}
+
+static struct pci_ops pcie_ops = {
+ .read = pcie_rd_conf,
+ .write = pcie_wr_conf,
+};
+
+/*
+ * Returns 0 when the device could not be initialized, 1 when
+ * initialization is successful
+ */
+static int __init armada_370_xp_pcie_setup(int nr, struct pci_sys_data *sys)
+{
+ struct pcie_port *port = &pcie_ports[nr];
+ unsigned long membase, iobase;
+ int ret;
+
+ if (!port->haslink)
+ return 0;
+
+ sys->private_data = port;
+ port->root_bus_nr = sys->busnr;
+ spin_lock_init(&port->conf_lock);
+
+ ret = armada_370_xp_alloc_pcie_window(port->port, port->lane,
+ IORESOURCE_MEM, SZ_64M, &membase);
+ if (ret) {
+ pr_err("PCIe%d.%d: Cannot get memory window, device disabled\n",
+ port->port, port->lane);
+ return 0;
+ }
+
+ ret = armada_370_xp_alloc_pcie_window(port->port, port->lane,
+ IORESOURCE_IO, SZ_64K, &iobase);
+ if (ret) {
+ pr_err("PCIe%d.%d: Cannot get I/O window, device disabled\n",
+ port->port, port->lane);
+ armada_370_xp_free_pcie_window(IORESOURCE_MEM, membase, SZ_64M);
+ return 0;
+ }
+
+ port->res.name = kasprintf(GFP_KERNEL, "PCIe %d.%d MEM",
+ port->port, port->lane);
+ if (!port->res.name) {
+ armada_370_xp_free_pcie_window(IORESOURCE_IO, iobase, SZ_64K);
+ armada_370_xp_free_pcie_window(IORESOURCE_MEM, membase, SZ_64M);
+ return 0;
+ }
+
+ port->res.start = membase;
+ port->res.end = membase + SZ_32M - 1;
+ port->res.flags = IORESOURCE_MEM;
+
+ pci_ioremap_io(SZ_64K * sys->busnr, iobase);
+
+ if (request_resource(&iomem_resource, &port->res)) {
+ pr_err("PCIe%d.%d: Cannot request memory resource\n",
+ port->port, port->lane);
+ kfree(port->res.name);
+ armada_370_xp_free_pcie_window(IORESOURCE_IO, iobase, SZ_64K);
+ armada_370_xp_free_pcie_window(IORESOURCE_MEM, membase, SZ_64M);
+ return 0;
+ }
+
+ pci_add_resource_offset(&sys->resources, &port->res, sys->mem_offset);
+
+ orion_pcie_set_local_bus_nr(port->base, sys->busnr);
+ orion_pcie_setup(port->base);
+
+ return 1;
+}
+
+static void __devinit rc_pci_fixup(struct pci_dev *dev)
+{
+ /*
+ * Prevent enumeration of root complex.
+ */
+ if (dev->bus->parent == NULL && dev->devfn == 0) {
+ int i;
+
+ for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
+ dev->resource[i].start = 0;
+ dev->resource[i].end = 0;
+ dev->resource[i].flags = 0;
+ }
+ }
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
+
+static int __init armada_370_xp_pcie_map_irq(const struct pci_dev *dev, u8 slot,
+ u8 pin)
+{
+ struct pci_sys_data *sys = dev->sysdata;
+ struct pcie_port *port = sys->private_data;
+
+ return port->irq;
+}
+
+static struct hw_pci armada_370_xp_pci __initdata = {
+ .setup = armada_370_xp_pcie_setup,
+ .map_irq = armada_370_xp_pcie_map_irq,
+ .ops = &pcie_ops,
+};
+
+static int __init armada_370_xp_pcie_probe(struct platform_device *pdev)
+{
+ struct device_node *child;
+ int nports, i;
+
+ nports = 0;
+ for_each_child_of_node(pdev->dev.of_node, child) {
+ if (!of_device_is_available(child))
+ continue;
+ nports++;
+ }
+
+ pcie_ports = devm_kzalloc(&pdev->dev, nports * sizeof(*pcie_ports),
+ GFP_KERNEL);
+ if (!pcie_ports)
+ return -ENOMEM;
+
+ i = 0;
+ for_each_child_of_node(pdev->dev.of_node, child) {
+ struct pcie_port *port = &pcie_ports[i];
+
+ if (!of_device_is_available(child))
+ continue;
+
+ if (of_property_read_u32(child, "marvell,pcie-port",
+ &port->port))
+ continue;
+
+ if (of_property_read_u32(child, "marvell,pcie-lane",
+ &port->lane))
+ port->lane = 0;
+
+ port->base = of_iomap(child, 0);
+ if (!port->base) {
+ dev_err(&pdev->dev, "PCIe%d.%d: cannot map registers\n",
+ port->port, port->lane);
+ continue;
+ }
+
+ if (orion_pcie_link_up(port->base)) {
+ port->haslink = 1;
+ dev_info(&pdev->dev, "PCIe%d.%d: link up\n",
+ port->port, port->lane);
+ } else {
+ port->haslink = 0;
+ dev_info(&pdev->dev, "PCIe%d.%d: link down\n",
+ port->port, port->lane);
+ iounmap(port->base);
+ continue;
+ }
+
+ port->irq = irq_of_parse_and_map(child, 0);
+ if (port->irq == 0) {
+ dev_err(&pdev->dev, "PCIe%d.%d: cannot parse and map IRQ\n",
+ port->port, port->lane);
+ iounmap(port->base);
+ port->haslink = 0;
+ continue;
+ }
+
+ port->clk = of_clk_get_by_name(child, NULL);
+ if (!port->clk) {
+ dev_err(&pdev->dev, "PCIe%d.%d: cannot get clock\n",
+ port->port, port->lane);
+ irq_dispose_mapping(port->irq);
+ iounmap(port->base);
+ port->haslink = 0;
+ continue;
+ }
+
+ clk_prepare_enable(port->clk);
+
+ i++;
+ }
+
+ armada_370_xp_pci.nr_controllers = nports;
+ pci_common_init(&armada_370_xp_pci);
+
+ return 0;
+}
+
+static const struct of_device_id armada_370_xp_pcie_of_match_table[] = {
+ { .compatible = "marvell,armada-370-xp-pcie", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, armada_370_xp_pcie_of_match_table);
+
+static struct platform_driver armada_370_xp_pcie_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "armada-370-xp-pcie",
+ .of_match_table =
+ of_match_ptr(armada_370_xp_pcie_of_match_table),
+ },
+};
+
+static int armada_370_xp_pcie_init(void)
+{
+ return platform_driver_probe(&armada_370_xp_pcie_driver,
+ armada_370_xp_pcie_probe);
+}
+
+subsys_initcall(armada_370_xp_pcie_init);
+
+MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni at free-electrons.com>");
+MODULE_DESCRIPTION("Marvell Armada 370/XP PCIe driver");
+MODULE_LICENSE("GPL");
--
1.7.9.5
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