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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/pci/controller/pci-thunder-pem.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/controller/pci-thunder-pem.c')
-rw-r--r--drivers/pci/controller/pci-thunder-pem.c474
1 files changed, 474 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 000000000..1650ec2c3
--- /dev/null
+++ b/drivers/pci/controller/pci-thunder-pem.c
@@ -0,0 +1,474 @@
+// 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 <linux/io-64-nonatomic-lo-hi.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] = lower_32_bits(bar4_start) | 2;
+ pem_pci->ea_entry[1] = lower_32_bits(res_pem->end - bar4_start) & ~3u;
+ pem_pci->ea_entry[2] = upper_32_bits(bar4_start);
+
+ cfg->priv = pem_pci;
+ return 0;
+}
+
+#if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
+
+#define PEM_RES_BASE 0x87e0c0000000ULL
+#define PEM_NODE_MASK GENMASK_ULL(45, 44)
+#define PEM_INDX_MASK GENMASK_ULL(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