PCI: Collect all native drivers under drivers/pci/controller/

Native PCI drivers for root complex devices were originally all in
drivers/pci/host/.  Some of these devices can also be operated in endpoint
mode.  Drivers for endpoint mode didn't seem to fit in the "host"
directory, so we put both the root complex and endpoint drivers in
per-device directories, e.g., drivers/pci/dwc/, drivers/pci/cadence/, etc.

These per-device directories contain trivial Kconfig and Makefiles and
clutter drivers/pci/.  Make a new drivers/pci/controllers/ directory and
collect all the device-specific drivers there.

No functional change intended.

Link: https://lkml.kernel.org/r/1520304202-232891-1-git-send-email-shawn.lin@rock-chips.com
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 473 insertions, 0 deletions

diff --git a/drivers/pci/controller/pci-thunder-pem.c b/drivers/pci/controller/pci-thunder-pem.c
new file mode 100644
index 0000000..f127ce8
--- /dev/null
+++ b/drivers/pci/controller/pci-thunder-pem.c
@@ -0,0 +1,473 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015 - 2016 Cavium, Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/pci-acpi.h>
+#include <linux/pci-ecam.h>
+#include <linux/platform_device.h>
+#include "../pci.h"
+
+#if defined(CONFIG_PCI_HOST_THUNDER_PEM) || (defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS))
+
+#define PEM_CFG_WR 0x28
+#define PEM_CFG_RD 0x30
+
+struct thunder_pem_pci {
+	u32		ea_entry[3];
+	void __iomem	*pem_reg_base;
+};
+
+static int thunder_pem_bridge_read(struct pci_bus *bus, unsigned int devfn,
+				   int where, int size, u32 *val)
+{
+	u64 read_val, tmp_val;
+	struct pci_config_window *cfg = bus->sysdata;
+	struct thunder_pem_pci *pem_pci = (struct thunder_pem_pci *)cfg->priv;
+
+	if (devfn != 0 || where >= 2048) {
+		*val = ~0;
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
+	/*
+	 * 32-bit accesses only.  Write the address to the low order
+	 * bits of PEM_CFG_RD, then trigger the read by reading back.
+	 * The config data lands in the upper 32-bits of PEM_CFG_RD.
+	 */
+	read_val = where & ~3ull;
+	writeq(read_val, pem_pci->pem_reg_base + PEM_CFG_RD);
+	read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
+	read_val >>= 32;
+
+	/*
+	 * The config space contains some garbage, fix it up.  Also
+	 * synthesize an EA capability for the BAR used by MSI-X.
+	 */
+	switch (where & ~3) {
+	case 0x40:
+		read_val &= 0xffff00ff;
+		read_val |= 0x00007000; /* Skip MSI CAP */
+		break;
+	case 0x70: /* Express Cap */
+		/*
+		 * Change PME interrupt to vector 2 on T88 where it
+		 * reads as 0, else leave it alone.
+		 */
+		if (!(read_val & (0x1f << 25)))
+			read_val |= (2u << 25);
+		break;
+	case 0xb0: /* MSI-X Cap */
+		/* TableSize=2 or 4, Next Cap is EA */
+		read_val &= 0xc00000ff;
+		/*
+		 * If Express Cap(0x70) raw PME vector reads as 0 we are on
+		 * T88 and TableSize is reported as 4, else TableSize
+		 * is 2.
+		 */
+		writeq(0x70, pem_pci->pem_reg_base + PEM_CFG_RD);
+		tmp_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
+		tmp_val >>= 32;
+		if (!(tmp_val & (0x1f << 25)))
+			read_val |= 0x0003bc00;
+		else
+			read_val |= 0x0001bc00;
+		break;
+	case 0xb4:
+		/* Table offset=0, BIR=0 */
+		read_val = 0x00000000;
+		break;
+	case 0xb8:
+		/* BPA offset=0xf0000, BIR=0 */
+		read_val = 0x000f0000;
+		break;
+	case 0xbc:
+		/* EA, 1 entry, no next Cap */
+		read_val = 0x00010014;
+		break;
+	case 0xc0:
+		/* DW2 for type-1 */
+		read_val = 0x00000000;
+		break;
+	case 0xc4:
+		/* Entry BEI=0, PP=0x00, SP=0xff, ES=3 */
+		read_val = 0x80ff0003;
+		break;
+	case 0xc8:
+		read_val = pem_pci->ea_entry[0];
+		break;
+	case 0xcc:
+		read_val = pem_pci->ea_entry[1];
+		break;
+	case 0xd0:
+		read_val = pem_pci->ea_entry[2];
+		break;
+	default:
+		break;
+	}
+	read_val >>= (8 * (where & 3));
+	switch (size) {
+	case 1:
+		read_val &= 0xff;
+		break;
+	case 2:
+		read_val &= 0xffff;
+		break;
+	default:
+		break;
+	}
+	*val = read_val;
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int thunder_pem_config_read(struct pci_bus *bus, unsigned int devfn,
+				   int where, int size, u32 *val)
+{
+	struct pci_config_window *cfg = bus->sysdata;
+
+	if (bus->number < cfg->busr.start ||
+	    bus->number > cfg->busr.end)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	/*
+	 * The first device on the bus is the PEM PCIe bridge.
+	 * Special case its config access.
+	 */
+	if (bus->number == cfg->busr.start)
+		return thunder_pem_bridge_read(bus, devfn, where, size, val);
+
+	return pci_generic_config_read(bus, devfn, where, size, val);
+}
+
+/*
+ * Some of the w1c_bits below also include read-only or non-writable
+ * reserved bits, this makes the code simpler and is OK as the bits
+ * are not affected by writing zeros to them.
+ */
+static u32 thunder_pem_bridge_w1c_bits(u64 where_aligned)
+{
+	u32 w1c_bits = 0;
+
+	switch (where_aligned) {
+	case 0x04: /* Command/Status */
+	case 0x1c: /* Base and I/O Limit/Secondary Status */
+		w1c_bits = 0xff000000;
+		break;
+	case 0x44: /* Power Management Control and Status */
+		w1c_bits = 0xfffffe00;
+		break;
+	case 0x78: /* Device Control/Device Status */
+	case 0x80: /* Link Control/Link Status */
+	case 0x88: /* Slot Control/Slot Status */
+	case 0x90: /* Root Status */
+	case 0xa0: /* Link Control 2 Registers/Link Status 2 */
+		w1c_bits = 0xffff0000;
+		break;
+	case 0x104: /* Uncorrectable Error Status */
+	case 0x110: /* Correctable Error Status */
+	case 0x130: /* Error Status */
+	case 0x160: /* Link Control 4 */
+		w1c_bits = 0xffffffff;
+		break;
+	default:
+		break;
+	}
+	return w1c_bits;
+}
+
+/* Some bits must be written to one so they appear to be read-only. */
+static u32 thunder_pem_bridge_w1_bits(u64 where_aligned)
+{
+	u32 w1_bits;
+
+	switch (where_aligned) {
+	case 0x1c: /* I/O Base / I/O Limit, Secondary Status */
+		/* Force 32-bit I/O addressing. */
+		w1_bits = 0x0101;
+		break;
+	case 0x24: /* Prefetchable Memory Base / Prefetchable Memory Limit */
+		/* Force 64-bit addressing */
+		w1_bits = 0x00010001;
+		break;
+	default:
+		w1_bits = 0;
+		break;
+	}
+	return w1_bits;
+}
+
+static int thunder_pem_bridge_write(struct pci_bus *bus, unsigned int devfn,
+				    int where, int size, u32 val)
+{
+	struct pci_config_window *cfg = bus->sysdata;
+	struct thunder_pem_pci *pem_pci = (struct thunder_pem_pci *)cfg->priv;
+	u64 write_val, read_val;
+	u64 where_aligned = where & ~3ull;
+	u32 mask = 0;
+
+
+	if (devfn != 0 || where >= 2048)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
+	/*
+	 * 32-bit accesses only.  If the write is for a size smaller
+	 * than 32-bits, we must first read the 32-bit value and merge
+	 * in the desired bits and then write the whole 32-bits back
+	 * out.
+	 */
+	switch (size) {
+	case 1:
+		writeq(where_aligned, pem_pci->pem_reg_base + PEM_CFG_RD);
+		read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
+		read_val >>= 32;
+		mask = ~(0xff << (8 * (where & 3)));
+		read_val &= mask;
+		val = (val & 0xff) << (8 * (where & 3));
+		val |= (u32)read_val;
+		break;
+	case 2:
+		writeq(where_aligned, pem_pci->pem_reg_base + PEM_CFG_RD);
+		read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
+		read_val >>= 32;
+		mask = ~(0xffff << (8 * (where & 3)));
+		read_val &= mask;
+		val = (val & 0xffff) << (8 * (where & 3));
+		val |= (u32)read_val;
+		break;
+	default:
+		break;
+	}
+
+	/*
+	 * By expanding the write width to 32 bits, we may
+	 * inadvertently hit some W1C bits that were not intended to
+	 * be written.  Calculate the mask that must be applied to the
+	 * data to be written to avoid these cases.
+	 */
+	if (mask) {
+		u32 w1c_bits = thunder_pem_bridge_w1c_bits(where);
+
+		if (w1c_bits) {
+			mask &= w1c_bits;
+			val &= ~mask;
+		}
+	}
+
+	/*
+	 * Some bits must be read-only with value of one.  Since the
+	 * access method allows these to be cleared if a zero is
+	 * written, force them to one before writing.
+	 */
+	val |= thunder_pem_bridge_w1_bits(where_aligned);
+
+	/*
+	 * Low order bits are the config address, the high order 32
+	 * bits are the data to be written.
+	 */
+	write_val = (((u64)val) << 32) | where_aligned;
+	writeq(write_val, pem_pci->pem_reg_base + PEM_CFG_WR);
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int thunder_pem_config_write(struct pci_bus *bus, unsigned int devfn,
+				    int where, int size, u32 val)
+{
+	struct pci_config_window *cfg = bus->sysdata;
+
+	if (bus->number < cfg->busr.start ||
+	    bus->number > cfg->busr.end)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+	/*
+	 * The first device on the bus is the PEM PCIe bridge.
+	 * Special case its config access.
+	 */
+	if (bus->number == cfg->busr.start)
+		return thunder_pem_bridge_write(bus, devfn, where, size, val);
+
+
+	return pci_generic_config_write(bus, devfn, where, size, val);
+}
+
+static int thunder_pem_init(struct device *dev, struct pci_config_window *cfg,
+			    struct resource *res_pem)
+{
+	struct thunder_pem_pci *pem_pci;
+	resource_size_t bar4_start;
+
+	pem_pci = devm_kzalloc(dev, sizeof(*pem_pci), GFP_KERNEL);
+	if (!pem_pci)
+		return -ENOMEM;
+
+	pem_pci->pem_reg_base = devm_ioremap(dev, res_pem->start, 0x10000);
+	if (!pem_pci->pem_reg_base)
+		return -ENOMEM;
+
+	/*
+	 * The MSI-X BAR for the PEM and AER interrupts is located at
+	 * a fixed offset from the PEM register base.  Generate a
+	 * fragment of the synthesized Enhanced Allocation capability
+	 * structure here for the BAR.
+	 */
+	bar4_start = res_pem->start + 0xf00000;
+	pem_pci->ea_entry[0] = (u32)bar4_start | 2;
+	pem_pci->ea_entry[1] = (u32)(res_pem->end - bar4_start) & ~3u;
+	pem_pci->ea_entry[2] = (u32)(bar4_start >> 32);
+
+	cfg->priv = pem_pci;
+	return 0;
+}
+
+#if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
+
+#define PEM_RES_BASE		0x87e0c0000000UL
+#define PEM_NODE_MASK		GENMASK(45, 44)
+#define PEM_INDX_MASK		GENMASK(26, 24)
+#define PEM_MIN_DOM_IN_NODE	4
+#define PEM_MAX_DOM_IN_NODE	10
+
+static void thunder_pem_reserve_range(struct device *dev, int seg,
+				      struct resource *r)
+{
+	resource_size_t start = r->start, end = r->end;
+	struct resource *res;
+	const char *regionid;
+
+	regionid = kasprintf(GFP_KERNEL, "PEM RC:%d", seg);
+	if (!regionid)
+		return;
+
+	res = request_mem_region(start, end - start + 1, regionid);
+	if (res)
+		res->flags &= ~IORESOURCE_BUSY;
+	else
+		kfree(regionid);
+
+	dev_info(dev, "%pR %s reserved\n", r,
+		 res ? "has been" : "could not be");
+}
+
+static void thunder_pem_legacy_fw(struct acpi_pci_root *root,
+				 struct resource *res_pem)
+{
+	int node = acpi_get_node(root->device->handle);
+	int index;
+
+	if (node == NUMA_NO_NODE)
+		node = 0;
+
+	index = root->segment - PEM_MIN_DOM_IN_NODE;
+	index -= node * PEM_MAX_DOM_IN_NODE;
+	res_pem->start = PEM_RES_BASE | FIELD_PREP(PEM_NODE_MASK, node) |
+					FIELD_PREP(PEM_INDX_MASK, index);
+	res_pem->flags = IORESOURCE_MEM;
+}
+
+static int thunder_pem_acpi_init(struct pci_config_window *cfg)
+{
+	struct device *dev = cfg->parent;
+	struct acpi_device *adev = to_acpi_device(dev);
+	struct acpi_pci_root *root = acpi_driver_data(adev);
+	struct resource *res_pem;
+	int ret;
+
+	res_pem = devm_kzalloc(&adev->dev, sizeof(*res_pem), GFP_KERNEL);
+	if (!res_pem)
+		return -ENOMEM;
+
+	ret = acpi_get_rc_resources(dev, "CAVA02B", root->segment, res_pem);
+
+	/*
+	 * If we fail to gather resources it means that we run with old
+	 * FW where we need to calculate PEM-specific resources manually.
+	 */
+	if (ret) {
+		thunder_pem_legacy_fw(root, res_pem);
+		/*
+		 * Reserve 64K size PEM specific resources. The full 16M range
+		 * size is required for thunder_pem_init() call.
+		 */
+		res_pem->end = res_pem->start + SZ_64K - 1;
+		thunder_pem_reserve_range(dev, root->segment, res_pem);
+		res_pem->end = res_pem->start + SZ_16M - 1;
+
+		/* Reserve PCI configuration space as well. */
+		thunder_pem_reserve_range(dev, root->segment, &cfg->res);
+	}
+
+	return thunder_pem_init(dev, cfg, res_pem);
+}
+
+struct pci_ecam_ops thunder_pem_ecam_ops = {
+	.bus_shift	= 24,
+	.init		= thunder_pem_acpi_init,
+	.pci_ops	= {
+		.map_bus	= pci_ecam_map_bus,
+		.read		= thunder_pem_config_read,
+		.write		= thunder_pem_config_write,
+	}
+};
+
+#endif
+
+#ifdef CONFIG_PCI_HOST_THUNDER_PEM
+
+static int thunder_pem_platform_init(struct pci_config_window *cfg)
+{
+	struct device *dev = cfg->parent;
+	struct platform_device *pdev = to_platform_device(dev);
+	struct resource *res_pem;
+
+	if (!dev->of_node)
+		return -EINVAL;
+
+	/*
+	 * The second register range is the PEM bridge to the PCIe
+	 * bus.  It has a different config access method than those
+	 * devices behind the bridge.
+	 */
+	res_pem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!res_pem) {
+		dev_err(dev, "missing \"reg[1]\"property\n");
+		return -EINVAL;
+	}
+
+	return thunder_pem_init(dev, cfg, res_pem);
+}
+
+static struct pci_ecam_ops pci_thunder_pem_ops = {
+	.bus_shift	= 24,
+	.init		= thunder_pem_platform_init,
+	.pci_ops	= {
+		.map_bus	= pci_ecam_map_bus,
+		.read		= thunder_pem_config_read,
+		.write		= thunder_pem_config_write,
+	}
+};
+
+static const struct of_device_id thunder_pem_of_match[] = {
+	{ .compatible = "cavium,pci-host-thunder-pem" },
+	{ },
+};
+
+static int thunder_pem_probe(struct platform_device *pdev)
+{
+	return pci_host_common_probe(pdev, &pci_thunder_pem_ops);
+}
+
+static struct platform_driver thunder_pem_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.of_match_table = thunder_pem_of_match,
+		.suppress_bind_attrs = true,
+	},
+	.probe = thunder_pem_probe,
+};
+builtin_platform_driver(thunder_pem_driver);
+
+#endif
+#endif