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path: root/drivers/pci/controller/pcie-cadence-host.c
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Diffstat (limited to 'drivers/pci/controller/pcie-cadence-host.c')
-rw-r--r--drivers/pci/controller/pcie-cadence-host.c336
1 files changed, 336 insertions, 0 deletions
diff --git a/drivers/pci/controller/pcie-cadence-host.c b/drivers/pci/controller/pcie-cadence-host.c
new file mode 100644
index 000000000000..a4ebbd37b553
--- /dev/null
+++ b/drivers/pci/controller/pcie-cadence-host.c
@@ -0,0 +1,336 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2017 Cadence
+// Cadence PCIe host controller driver.
+// Author: Cyrille Pitchen <cyrille.pitchen@free-electrons.com>
+
+#include <linux/kernel.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include "pcie-cadence.h"
+
+/**
+ * struct cdns_pcie_rc - private data for this PCIe Root Complex driver
+ * @pcie: Cadence PCIe controller
+ * @dev: pointer to PCIe device
+ * @cfg_res: start/end offsets in the physical system memory to map PCI
+ * configuration space accesses
+ * @bus_range: first/last buses behind the PCIe host controller
+ * @cfg_base: IO mapped window to access the PCI configuration space of a
+ * single function at a time
+ * @max_regions: maximum number of regions supported by the hardware
+ * @no_bar_nbits: Number of bits to keep for inbound (PCIe -> CPU) address
+ * translation (nbits sets into the "no BAR match" register)
+ * @vendor_id: PCI vendor ID
+ * @device_id: PCI device ID
+ */
+struct cdns_pcie_rc {
+ struct cdns_pcie pcie;
+ struct device *dev;
+ struct resource *cfg_res;
+ struct resource *bus_range;
+ void __iomem *cfg_base;
+ u32 max_regions;
+ u32 no_bar_nbits;
+ u16 vendor_id;
+ u16 device_id;
+};
+
+static void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
+ int where)
+{
+ struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
+ struct cdns_pcie_rc *rc = pci_host_bridge_priv(bridge);
+ struct cdns_pcie *pcie = &rc->pcie;
+ unsigned int busn = bus->number;
+ u32 addr0, desc0;
+
+ if (busn == rc->bus_range->start) {
+ /*
+ * Only the root port (devfn == 0) is connected to this bus.
+ * All other PCI devices are behind some bridge hence on another
+ * bus.
+ */
+ if (devfn)
+ return NULL;
+
+ return pcie->reg_base + (where & 0xfff);
+ }
+
+ /* Update Output registers for AXI region 0. */
+ addr0 = CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_NBITS(12) |
+ CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_DEVFN(devfn) |
+ CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_BUS(busn);
+ cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR0(0), addr0);
+
+ /* Configuration Type 0 or Type 1 access. */
+ desc0 = CDNS_PCIE_AT_OB_REGION_DESC0_HARDCODED_RID |
+ CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(0);
+ /*
+ * The bus number was already set once for all in desc1 by
+ * cdns_pcie_host_init_address_translation().
+ */
+ if (busn == rc->bus_range->start + 1)
+ desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_CONF_TYPE0;
+ else
+ desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_CONF_TYPE1;
+ cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC0(0), desc0);
+
+ return rc->cfg_base + (where & 0xfff);
+}
+
+static struct pci_ops cdns_pcie_host_ops = {
+ .map_bus = cdns_pci_map_bus,
+ .read = pci_generic_config_read,
+ .write = pci_generic_config_write,
+};
+
+static const struct of_device_id cdns_pcie_host_of_match[] = {
+ { .compatible = "cdns,cdns-pcie-host" },
+
+ { },
+};
+
+static int cdns_pcie_host_init_root_port(struct cdns_pcie_rc *rc)
+{
+ struct cdns_pcie *pcie = &rc->pcie;
+ u32 value, ctrl;
+
+ /*
+ * Set the root complex BAR configuration register:
+ * - disable both BAR0 and BAR1.
+ * - enable Prefetchable Memory Base and Limit registers in type 1
+ * config space (64 bits).
+ * - enable IO Base and Limit registers in type 1 config
+ * space (32 bits).
+ */
+ ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_DISABLED;
+ value = CDNS_PCIE_LM_RC_BAR_CFG_BAR0_CTRL(ctrl) |
+ CDNS_PCIE_LM_RC_BAR_CFG_BAR1_CTRL(ctrl) |
+ CDNS_PCIE_LM_RC_BAR_CFG_PREFETCH_MEM_ENABLE |
+ CDNS_PCIE_LM_RC_BAR_CFG_PREFETCH_MEM_64BITS |
+ CDNS_PCIE_LM_RC_BAR_CFG_IO_ENABLE |
+ CDNS_PCIE_LM_RC_BAR_CFG_IO_32BITS;
+ cdns_pcie_writel(pcie, CDNS_PCIE_LM_RC_BAR_CFG, value);
+
+ /* Set root port configuration space */
+ if (rc->vendor_id != 0xffff)
+ cdns_pcie_rp_writew(pcie, PCI_VENDOR_ID, rc->vendor_id);
+ if (rc->device_id != 0xffff)
+ cdns_pcie_rp_writew(pcie, PCI_DEVICE_ID, rc->device_id);
+
+ cdns_pcie_rp_writeb(pcie, PCI_CLASS_REVISION, 0);
+ cdns_pcie_rp_writeb(pcie, PCI_CLASS_PROG, 0);
+ cdns_pcie_rp_writew(pcie, PCI_CLASS_DEVICE, PCI_CLASS_BRIDGE_PCI);
+
+ return 0;
+}
+
+static int cdns_pcie_host_init_address_translation(struct cdns_pcie_rc *rc)
+{
+ struct cdns_pcie *pcie = &rc->pcie;
+ struct resource *cfg_res = rc->cfg_res;
+ struct resource *mem_res = pcie->mem_res;
+ struct resource *bus_range = rc->bus_range;
+ struct device *dev = rc->dev;
+ struct device_node *np = dev->of_node;
+ struct of_pci_range_parser parser;
+ struct of_pci_range range;
+ u32 addr0, addr1, desc1;
+ u64 cpu_addr;
+ int r, err;
+
+ /*
+ * Reserve region 0 for PCI configure space accesses:
+ * OB_REGION_PCI_ADDR0 and OB_REGION_DESC0 are updated dynamically by
+ * cdns_pci_map_bus(), other region registers are set here once for all.
+ */
+ addr1 = 0; /* Should be programmed to zero. */
+ desc1 = CDNS_PCIE_AT_OB_REGION_DESC1_BUS(bus_range->start);
+ cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR1(0), addr1);
+ cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC1(0), desc1);
+
+ cpu_addr = cfg_res->start - mem_res->start;
+ addr0 = CDNS_PCIE_AT_OB_REGION_CPU_ADDR0_NBITS(12) |
+ (lower_32_bits(cpu_addr) & GENMASK(31, 8));
+ addr1 = upper_32_bits(cpu_addr);
+ cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(0), addr0);
+ cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(0), addr1);
+
+ err = of_pci_range_parser_init(&parser, np);
+ if (err)
+ return err;
+
+ r = 1;
+ for_each_of_pci_range(&parser, &range) {
+ bool is_io;
+
+ if (r >= rc->max_regions)
+ break;
+
+ if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM)
+ is_io = false;
+ else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_IO)
+ is_io = true;
+ else
+ continue;
+
+ cdns_pcie_set_outbound_region(pcie, 0, r, is_io,
+ range.cpu_addr,
+ range.pci_addr,
+ range.size);
+ r++;
+ }
+
+ /*
+ * Set Root Port no BAR match Inbound Translation registers:
+ * needed for MSI and DMA.
+ * Root Port BAR0 and BAR1 are disabled, hence no need to set their
+ * inbound translation registers.
+ */
+ addr0 = CDNS_PCIE_AT_IB_RP_BAR_ADDR0_NBITS(rc->no_bar_nbits);
+ addr1 = 0;
+ cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_RP_BAR_ADDR0(RP_NO_BAR), addr0);
+ cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_RP_BAR_ADDR1(RP_NO_BAR), addr1);
+
+ return 0;
+}
+
+static int cdns_pcie_host_init(struct device *dev,
+ struct list_head *resources,
+ struct cdns_pcie_rc *rc)
+{
+ struct resource *bus_range = NULL;
+ int err;
+
+ /* Parse our PCI ranges and request their resources */
+ err = pci_parse_request_of_pci_ranges(dev, resources, &bus_range);
+ if (err)
+ return err;
+
+ rc->bus_range = bus_range;
+ rc->pcie.bus = bus_range->start;
+
+ err = cdns_pcie_host_init_root_port(rc);
+ if (err)
+ goto err_out;
+
+ err = cdns_pcie_host_init_address_translation(rc);
+ if (err)
+ goto err_out;
+
+ return 0;
+
+ err_out:
+ pci_free_resource_list(resources);
+ return err;
+}
+
+static int cdns_pcie_host_probe(struct platform_device *pdev)
+{
+ const char *type;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct pci_host_bridge *bridge;
+ struct list_head resources;
+ struct cdns_pcie_rc *rc;
+ struct cdns_pcie *pcie;
+ struct resource *res;
+ int ret;
+
+ bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
+ if (!bridge)
+ return -ENOMEM;
+
+ rc = pci_host_bridge_priv(bridge);
+ rc->dev = dev;
+
+ pcie = &rc->pcie;
+ pcie->is_rc = true;
+
+ rc->max_regions = 32;
+ of_property_read_u32(np, "cdns,max-outbound-regions", &rc->max_regions);
+
+ rc->no_bar_nbits = 32;
+ of_property_read_u32(np, "cdns,no-bar-match-nbits", &rc->no_bar_nbits);
+
+ rc->vendor_id = 0xffff;
+ of_property_read_u16(np, "vendor-id", &rc->vendor_id);
+
+ rc->device_id = 0xffff;
+ of_property_read_u16(np, "device-id", &rc->device_id);
+
+ type = of_get_property(np, "device_type", NULL);
+ if (!type || strcmp(type, "pci")) {
+ dev_err(dev, "invalid \"device_type\" %s\n", type);
+ return -EINVAL;
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg");
+ pcie->reg_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(pcie->reg_base)) {
+ dev_err(dev, "missing \"reg\"\n");
+ return PTR_ERR(pcie->reg_base);
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
+ rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
+ if (IS_ERR(rc->cfg_base)) {
+ dev_err(dev, "missing \"cfg\"\n");
+ return PTR_ERR(rc->cfg_base);
+ }
+ rc->cfg_res = res;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem");
+ if (!res) {
+ dev_err(dev, "missing \"mem\"\n");
+ return -EINVAL;
+ }
+ pcie->mem_res = res;
+
+ pm_runtime_enable(dev);
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ dev_err(dev, "pm_runtime_get_sync() failed\n");
+ goto err_get_sync;
+ }
+
+ ret = cdns_pcie_host_init(dev, &resources, rc);
+ if (ret)
+ goto err_init;
+
+ list_splice_init(&resources, &bridge->windows);
+ bridge->dev.parent = dev;
+ bridge->busnr = pcie->bus;
+ bridge->ops = &cdns_pcie_host_ops;
+ bridge->map_irq = of_irq_parse_and_map_pci;
+ bridge->swizzle_irq = pci_common_swizzle;
+
+ ret = pci_host_probe(bridge);
+ if (ret < 0)
+ goto err_host_probe;
+
+ return 0;
+
+ err_host_probe:
+ pci_free_resource_list(&resources);
+
+ err_init:
+ pm_runtime_put_sync(dev);
+
+ err_get_sync:
+ pm_runtime_disable(dev);
+
+ return ret;
+}
+
+static struct platform_driver cdns_pcie_host_driver = {
+ .driver = {
+ .name = "cdns-pcie-host",
+ .of_match_table = cdns_pcie_host_of_match,
+ },
+ .probe = cdns_pcie_host_probe,
+};
+builtin_platform_driver(cdns_pcie_host_driver);