|  | // 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 |