9 files changed, 60 insertions, 199 deletions

diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 34ec1d88f961..3b1059190867 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -34,6 +34,8 @@ obj-$(CONFIG_VMD) += vmd.o
 # ARM64 and use internal ifdefs to only build the pieces we need
 # depending on whether ACPI, the DT driver, or both are enabled.
 
+ifdef CONFIG_PCI
 obj-$(CONFIG_ARM64) += pci-thunder-ecam.o
 obj-$(CONFIG_ARM64) += pci-thunder-pem.o
 obj-$(CONFIG_ARM64) += pci-xgene.o
+endif
diff --git a/drivers/pci/host/pci-host-common.c b/drivers/pci/host/pci-host-common.c
index 31f2c231e893..5d028f53fdcd 100644
--- a/drivers/pci/host/pci-host-common.c
+++ b/drivers/pci/host/pci-host-common.c
@@ -13,50 +13,6 @@
 #include <linux/pci-ecam.h>
 #include <linux/platform_device.h>
 
-static int gen_pci_parse_request_of_pci_ranges(struct device *dev,
-		       struct list_head *resources, struct resource **bus_range)
-{
-	int err, res_valid = 0;
-	struct device_node *np = dev->of_node;
-	resource_size_t iobase;
-	struct resource_entry *win, *tmp;
-
-	err = of_pci_get_host_bridge_resources(np, 0, 0xff, resources, &iobase);
-	if (err)
-		return err;
-
-	err = devm_request_pci_bus_resources(dev, resources);
-	if (err)
-		return err;
-
-	resource_list_for_each_entry_safe(win, tmp, resources) {
-		struct resource *res = win->res;
-
-		switch (resource_type(res)) {
-		case IORESOURCE_IO:
-			err = pci_remap_iospace(res, iobase);
-			if (err) {
-				dev_warn(dev, "error %d: failed to map resource %pR\n",
-					 err, res);
-				resource_list_destroy_entry(win);
-			}
-			break;
-		case IORESOURCE_MEM:
-			res_valid |= !(res->flags & IORESOURCE_PREFETCH);
-			break;
-		case IORESOURCE_BUS:
-			*bus_range = res;
-			break;
-		}
-	}
-
-	if (res_valid)
-		return 0;
-
-	dev_err(dev, "non-prefetchable memory resource required\n");
-	return -EINVAL;
-}
-
 static void gen_pci_unmap_cfg(void *ptr)
 {
 	pci_ecam_free((struct pci_config_window *)ptr);
@@ -71,9 +27,9 @@ static struct pci_config_window *gen_pci_init(struct device *dev,
 	struct pci_config_window *cfg;
 
 	/* Parse our PCI ranges and request their resources */
-	err = gen_pci_parse_request_of_pci_ranges(dev, resources, &bus_range);
+	err = pci_parse_request_of_pci_ranges(dev, resources, &bus_range);
 	if (err)
-		goto err_out;
+		return ERR_PTR(err);
 
 	err = of_address_to_resource(dev->of_node, 0, &cfgres);
 	if (err) {
@@ -105,7 +61,6 @@ int pci_host_common_probe(struct platform_device *pdev,
 	const char *type;
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
-	struct pci_bus *bus, *child;
 	struct pci_host_bridge *bridge;
 	struct pci_config_window *cfg;
 	struct list_head resources;
@@ -124,14 +79,13 @@ int pci_host_common_probe(struct platform_device *pdev,
 	of_pci_check_probe_only();
 
 	/* Parse and map our Configuration Space windows */
-	INIT_LIST_HEAD(&resources);
 	cfg = gen_pci_init(dev, &resources, ops);
 	if (IS_ERR(cfg))
 		return PTR_ERR(cfg);
 
 	/* Do not reassign resources if probe only */
 	if (!pci_has_flag(PCI_PROBE_ONLY))
-		pci_add_flags(PCI_REASSIGN_ALL_RSRC | PCI_REASSIGN_ALL_BUS);
+		pci_add_flags(PCI_REASSIGN_ALL_BUS);
 
 	list_splice_init(&resources, &bridge->windows);
 	bridge->dev.parent = dev;
@@ -141,29 +95,11 @@ int pci_host_common_probe(struct platform_device *pdev,
 	bridge->map_irq = of_irq_parse_and_map_pci;
 	bridge->swizzle_irq = pci_common_swizzle;
 
-	ret = pci_scan_root_bus_bridge(bridge);
+	ret = pci_host_probe(bridge);
 	if (ret < 0) {
-		dev_err(dev, "Scanning root bridge failed");
+		pci_free_resource_list(&resources);
 		return ret;
 	}
 
-	bus = bridge->bus;
-
-	/*
-	 * We insert PCI resources into the iomem_resource and
-	 * ioport_resource trees in either pci_bus_claim_resources()
-	 * or pci_bus_assign_resources().
-	 */
-	if (pci_has_flag(PCI_PROBE_ONLY)) {
-		pci_bus_claim_resources(bus);
-	} else {
-		pci_bus_size_bridges(bus);
-		pci_bus_assign_resources(bus);
-
-		list_for_each_entry(child, &bus->children, node)
-			pcie_bus_configure_settings(child);
-	}
-
-	pci_bus_add_devices(bus);
 	return 0;
 }
diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c
index 8ff28057ec02..dd9b3bcc41c3 100644
--- a/drivers/pci/host/pci-tegra.c
+++ b/drivers/pci/host/pci-tegra.c
@@ -256,11 +256,10 @@ struct tegra_pcie {
 
 	void __iomem *pads;
 	void __iomem *afi;
+	void __iomem *cfg;
 	int irq;
 
-	struct list_head buses;
-	struct resource *cs;
-
+	struct resource cs;
 	struct resource io;
 	struct resource pio;
 	struct resource mem;
@@ -309,7 +308,6 @@ struct tegra_pcie_port {
 };
 
 struct tegra_pcie_bus {
-	struct vm_struct *area;
 	struct list_head list;
 	unsigned int nr;
 };
@@ -349,109 +347,26 @@ static inline u32 pads_readl(struct tegra_pcie *pcie, unsigned long offset)
  *
  * Mapping the whole extended configuration space would require 256 MiB of
  * virtual address space, only a small part of which will actually be used.
- * To work around this, a 1 MiB of virtual addresses are allocated per bus
- * when the bus is first accessed. When the physical range is mapped, the
- * the bus number bits are hidden so that the extended register number bits
- * appear as bits [19:16]. Therefore the virtual mapping looks like this:
- *
- *    [19:16] extended register number
- *    [15:11] device number
- *    [10: 8] function number
- *    [ 7: 0] register number
  *
- * This is achieved by stitching together 16 chunks of 64 KiB of physical
- * address space via the MMU.
+ * To work around this, a 4 KiB region is used to generate the required
+ * configuration transaction with relevant B:D:F and register offset values.
+ * This is achieved by dynamically programming base address and size of
+ * AFI_AXI_BAR used for end point config space mapping to make sure that the
+ * address (access to which generates correct config transaction) falls in
+ * this 4 KiB region.
  */
-static unsigned long tegra_pcie_conf_offset(unsigned int devfn, int where)
+static unsigned int tegra_pcie_conf_offset(u8 bus, unsigned int devfn,
+					   unsigned int where)
 {
-	return ((where & 0xf00) << 8) | (PCI_SLOT(devfn) << 11) |
-	       (PCI_FUNC(devfn) << 8) | (where & 0xfc);
-}
-
-static struct tegra_pcie_bus *tegra_pcie_bus_alloc(struct tegra_pcie *pcie,
-						   unsigned int busnr)
-{
-	struct device *dev = pcie->dev;
-	pgprot_t prot = pgprot_noncached(PAGE_KERNEL);
-	phys_addr_t cs = pcie->cs->start;
-	struct tegra_pcie_bus *bus;
-	unsigned int i;
-	int err;
-
-	bus = kzalloc(sizeof(*bus), GFP_KERNEL);
-	if (!bus)
-		return ERR_PTR(-ENOMEM);
-
-	INIT_LIST_HEAD(&bus->list);
-	bus->nr = busnr;
-
-	/* allocate 1 MiB of virtual addresses */
-	bus->area = get_vm_area(SZ_1M, VM_IOREMAP);
-	if (!bus->area) {
-		err = -ENOMEM;
-		goto free;
-	}
-
-	/* map each of the 16 chunks of 64 KiB each */
-	for (i = 0; i < 16; i++) {
-		unsigned long virt = (unsigned long)bus->area->addr +
-				     i * SZ_64K;
-		phys_addr_t phys = cs + i * SZ_16M + busnr * SZ_64K;
-
-		err = ioremap_page_range(virt, virt + SZ_64K, phys, prot);
-		if (err < 0) {
-			dev_err(dev, "ioremap_page_range() failed: %d\n", err);
-			goto unmap;
-		}
-	}
-
-	return bus;
-
-unmap:
-	vunmap(bus->area->addr);
-free:
-	kfree(bus);
-	return ERR_PTR(err);
-}
-
-static int tegra_pcie_add_bus(struct pci_bus *bus)
-{
-	struct pci_host_bridge *host = pci_find_host_bridge(bus);
-	struct tegra_pcie *pcie = pci_host_bridge_priv(host);
-	struct tegra_pcie_bus *b;
-
-	b = tegra_pcie_bus_alloc(pcie, bus->number);
-	if (IS_ERR(b))
-		return PTR_ERR(b);
-
-	list_add_tail(&b->list, &pcie->buses);
-
-	return 0;
-}
-
-static void tegra_pcie_remove_bus(struct pci_bus *child)
-{
-	struct pci_host_bridge *host = pci_find_host_bridge(child);
-	struct tegra_pcie *pcie = pci_host_bridge_priv(host);
-	struct tegra_pcie_bus *bus, *tmp;
-
-	list_for_each_entry_safe(bus, tmp, &pcie->buses, list) {
-		if (bus->nr == child->number) {
-			vunmap(bus->area->addr);
-			list_del(&bus->list);
-			kfree(bus);
-			break;
-		}
-	}
+	return ((where & 0xf00) << 16) | (bus << 16) | (PCI_SLOT(devfn) << 11) |
+	       (PCI_FUNC(devfn) << 8) | (where & 0xff);
 }
 
 static void __iomem *tegra_pcie_map_bus(struct pci_bus *bus,
 					unsigned int devfn,
 					int where)
 {
-	struct pci_host_bridge *host = pci_find_host_bridge(bus);
-	struct tegra_pcie *pcie = pci_host_bridge_priv(host);
-	struct device *dev = pcie->dev;
+	struct tegra_pcie *pcie = bus->sysdata;
 	void __iomem *addr = NULL;
 
 	if (bus->number == 0) {
@@ -465,19 +380,17 @@ static void __iomem *tegra_pcie_map_bus(struct pci_bus *bus,
 			}
 		}
 	} else {
-		struct tegra_pcie_bus *b;
+		unsigned int offset;
+		u32 base;
 
-		list_for_each_entry(b, &pcie->buses, list)
-			if (b->nr == bus->number)
-				addr = (void __iomem *)b->area->addr;
+		offset = tegra_pcie_conf_offset(bus->number, devfn, where);
 
-		if (!addr) {
-			dev_err(dev, "failed to map cfg. space for bus %u\n",
-				bus->number);
-			return NULL;
-		}
+		/* move 4 KiB window to offset within the FPCI region */
+		base = 0xfe100000 + ((offset & ~(SZ_4K - 1)) >> 8);
+		afi_writel(pcie, base, AFI_FPCI_BAR0);
 
-		addr += tegra_pcie_conf_offset(devfn, where);
+		/* move to correct offset within the 4 KiB page */
+		addr = pcie->cfg + (offset & (SZ_4K - 1));
 	}
 
 	return addr;
@@ -504,8 +417,6 @@ static int tegra_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
 }
 
 static struct pci_ops tegra_pcie_ops = {
-	.add_bus = tegra_pcie_add_bus,
-	.remove_bus = tegra_pcie_remove_bus,
 	.map_bus = tegra_pcie_map_bus,
 	.read = tegra_pcie_config_read,
 	.write = tegra_pcie_config_write,
@@ -648,8 +559,7 @@ static int tegra_pcie_request_resources(struct tegra_pcie *pcie)
 
 static int tegra_pcie_map_irq(const struct pci_dev *pdev, u8 slot, u8 pin)
 {
-	struct pci_host_bridge *host = pci_find_host_bridge(pdev->bus);
-	struct tegra_pcie *pcie = pci_host_bridge_priv(host);
+	struct tegra_pcie *pcie = pdev->bus->sysdata;
 	int irq;
 
 	tegra_cpuidle_pcie_irqs_in_use();
@@ -730,12 +640,9 @@ static void tegra_pcie_setup_translations(struct tegra_pcie *pcie)
 	u32 fpci_bar, size, axi_address;
 
 	/* Bar 0: type 1 extended configuration space */
-	fpci_bar = 0xfe100000;
-	size = resource_size(pcie->cs);
-	axi_address = pcie->cs->start;
-	afi_writel(pcie, axi_address, AFI_AXI_BAR0_START);
+	size = resource_size(&pcie->cs);
+	afi_writel(pcie, pcie->cs.start, AFI_AXI_BAR0_START);
 	afi_writel(pcie, size >> 12, AFI_AXI_BAR0_SZ);
-	afi_writel(pcie, fpci_bar, AFI_FPCI_BAR0);
 
 	/* Bar 1: downstream IO bar */
 	fpci_bar = 0xfdfc0000;
@@ -1340,10 +1247,14 @@ static int tegra_pcie_get_resources(struct tegra_pcie *pcie)
 		goto poweroff;
 	}
 
-	pcie->cs = devm_request_mem_region(dev, res->start,
-					   resource_size(res), res->name);
-	if (!pcie->cs) {
-		err = -EADDRNOTAVAIL;
+	pcie->cs = *res;
+
+	/* constrain configuration space to 4 KiB */
+	pcie->cs.end = pcie->cs.start + SZ_4K - 1;
+
+	pcie->cfg = devm_ioremap_resource(dev, &pcie->cs);
+	if (IS_ERR(pcie->cfg)) {
+		err = PTR_ERR(pcie->cfg);
 		goto poweroff;
 	}
 
@@ -2332,9 +2243,9 @@ static int tegra_pcie_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	pcie = pci_host_bridge_priv(host);
+	host->sysdata = pcie;
 
 	pcie->soc = of_device_get_match_data(dev);
-	INIT_LIST_HEAD(&pcie->buses);
 	INIT_LIST_HEAD(&pcie->ports);
 	pcie->dev = dev;
 
@@ -2369,7 +2280,6 @@ static int tegra_pcie_probe(struct platform_device *pdev)
 
 	tegra_pcie_enable_ports(pcie);
 
-	pci_add_flags(PCI_REASSIGN_ALL_RSRC | PCI_REASSIGN_ALL_BUS);
 	host->busnr = pcie->busn.start;
 	host->dev.parent = &pdev->dev;
 	host->ops = &tegra_pcie_ops;
diff --git a/drivers/pci/host/pci-versatile.c b/drivers/pci/host/pci-versatile.c
index b5b59d058c1b..5b3876f5312b 100644
--- a/drivers/pci/host/pci-versatile.c
+++ b/drivers/pci/host/pci-versatile.c
@@ -194,7 +194,7 @@ static int versatile_pci_probe(struct platform_device *pdev)
 	writel(0, versatile_cfg_base[0] + PCI_INTERRUPT_LINE);
 
 	pci_add_flags(PCI_ENABLE_PROC_DOMAINS);
-	pci_add_flags(PCI_REASSIGN_ALL_BUS | PCI_REASSIGN_ALL_RSRC);
+	pci_add_flags(PCI_REASSIGN_ALL_BUS);
 
 	list_splice_init(&pci_res, &bridge->windows);
 	bridge->dev.parent = dev;
diff --git a/drivers/pci/host/pci-xgene.c b/drivers/pci/host/pci-xgene.c
index 2fc106d52aff..0a0d7ee6d3c9 100644
--- a/drivers/pci/host/pci-xgene.c
+++ b/drivers/pci/host/pci-xgene.c
@@ -658,7 +658,6 @@ static int xgene_pcie_probe(struct platform_device *pdev)
 
 	bus = bridge->bus;
 
-	pci_scan_child_bus(bus);
 	pci_assign_unassigned_bus_resources(bus);
 	list_for_each_entry(child, &bus->children, node)
 		pcie_bus_configure_settings(child);
diff --git a/drivers/pci/host/pcie-iproc-platform.c b/drivers/pci/host/pcie-iproc-platform.c
index 3e6927c318f2..e764a2a2693c 100644
--- a/drivers/pci/host/pcie-iproc-platform.c
+++ b/drivers/pci/host/pcie-iproc-platform.c
@@ -84,6 +84,13 @@ static int iproc_pcie_pltfm_probe(struct platform_device *pdev)
 		pcie->need_ob_cfg = true;
 	}
 
+	/*
+	 * DT nodes are not used by all platforms that use the iProc PCIe
+	 * core driver. For platforms that require explict inbound mapping
+	 * configuration, "dma-ranges" would have been present in DT
+	 */
+	pcie->need_ib_cfg = of_property_read_bool(np, "dma-ranges");
+
 	/* PHY use is optional */
 	pcie->phy = devm_phy_get(dev, "pcie-phy");
 	if (IS_ERR(pcie->phy)) {
diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
index 331dab12daee..cbb095481cdc 100644
--- a/drivers/pci/host/pcie-iproc.c
+++ b/drivers/pci/host/pcie-iproc.c
@@ -1370,9 +1370,11 @@ int iproc_pcie_setup(struct iproc_pcie *pcie, struct list_head *res)
 		}
 	}
 
-	ret = iproc_pcie_map_dma_ranges(pcie);
-	if (ret && ret != -ENOENT)
-		goto err_power_off_phy;
+	if (pcie->need_ib_cfg) {
+		ret = iproc_pcie_map_dma_ranges(pcie);
+		if (ret && ret != -ENOENT)
+			goto err_power_off_phy;
+	}
 
 #ifdef CONFIG_ARM
 	pcie->sysdata.private_data = pcie;
diff --git a/drivers/pci/host/pcie-iproc.h b/drivers/pci/host/pcie-iproc.h
index 944d546fba2a..d55f56a186cd 100644
--- a/drivers/pci/host/pcie-iproc.h
+++ b/drivers/pci/host/pcie-iproc.h
@@ -66,6 +66,7 @@ struct iproc_msi;
  * @ob: outbound mapping related parameters
  * @ob_map: outbound mapping related parameters specific to the controller
  *
+ * @need_ib_cfg: indicates SW needs to configure the inbound mapping window
  * @ib: inbound mapping related parameters
  * @ib_map: outbound mapping region related parameters
  *
@@ -93,6 +94,7 @@ struct iproc_pcie {
 	struct iproc_pcie_ob ob;
 	const struct iproc_pcie_ob_map *ob_map;
 
+	bool need_ib_cfg;
 	struct iproc_pcie_ib ib;
 	const struct iproc_pcie_ib_map *ib_map;
 
diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c
index 5efce1f237c5..b4c4aad2cf66 100644
--- a/drivers/pci/host/pcie-rcar.c
+++ b/drivers/pci/host/pcie-rcar.c
@@ -456,7 +456,7 @@ static int rcar_pcie_enable(struct rcar_pcie *pcie)
 
 	rcar_pcie_setup(&bridge->windows, pcie);
 
-	pci_add_flags(PCI_REASSIGN_ALL_RSRC | PCI_REASSIGN_ALL_BUS);
+	pci_add_flags(PCI_REASSIGN_ALL_BUS);
 
 	bridge->dev.parent = dev;
 	bridge->sysdata = pcie;
@@ -1120,7 +1120,9 @@ static int rcar_pcie_probe(struct platform_device *pdev)
 
 	INIT_LIST_HEAD(&pcie->resources);
 
-	rcar_pcie_parse_request_of_pci_ranges(pcie);
+	err = rcar_pcie_parse_request_of_pci_ranges(pcie);
+	if (err)
+		goto err_free_bridge;
 
 	err = rcar_pcie_get_resources(pcie);
 	if (err < 0) {
@@ -1175,6 +1177,7 @@ err_pm_disable:
 
 err_free_resource_list:
 	pci_free_resource_list(&pcie->resources);
+err_free_bridge:
 	pci_free_host_bridge(bridge);
 
 	return err;