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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 | // SPDX-License-Identifier: GPL-2.0 /* * Copyright 2016 Broadcom */ #include <linux/device.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/pci.h> #include <linux/pci-ecam.h> #include <linux/slab.h> /* * On 64-bit systems, we do a single ioremap for the whole config space * since we have enough virtual address range available. On 32-bit, we * ioremap the config space for each bus individually. */ static const bool per_bus_mapping = !IS_ENABLED(CONFIG_64BIT); /* * Create a PCI config space window * - reserve mem region * - alloc struct pci_config_window with space for all mappings * - ioremap the config space */ struct pci_config_window *pci_ecam_create(struct device *dev, struct resource *cfgres, struct resource *busr, struct pci_ecam_ops *ops) { struct pci_config_window *cfg; unsigned int bus_range, bus_range_max, bsz; struct resource *conflict; int i, err; if (busr->start > busr->end) return ERR_PTR(-EINVAL); cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); if (!cfg) return ERR_PTR(-ENOMEM); cfg->parent = dev; cfg->ops = ops; cfg->busr.start = busr->start; cfg->busr.end = busr->end; cfg->busr.flags = IORESOURCE_BUS; bus_range = resource_size(&cfg->busr); bus_range_max = resource_size(cfgres) >> ops->bus_shift; if (bus_range > bus_range_max) { bus_range = bus_range_max; cfg->busr.end = busr->start + bus_range - 1; dev_warn(dev, "ECAM area %pR can only accommodate %pR (reduced from %pR desired)\n", cfgres, &cfg->busr, busr); } bsz = 1 << ops->bus_shift; cfg->res.start = cfgres->start; cfg->res.end = cfgres->end; cfg->res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; cfg->res.name = "PCI ECAM"; conflict = request_resource_conflict(&iomem_resource, &cfg->res); if (conflict) { err = -EBUSY; dev_err(dev, "can't claim ECAM area %pR: address conflict with %s %pR\n", &cfg->res, conflict->name, conflict); goto err_exit; } if (per_bus_mapping) { cfg->winp = kcalloc(bus_range, sizeof(*cfg->winp), GFP_KERNEL); if (!cfg->winp) goto err_exit_malloc; for (i = 0; i < bus_range; i++) { cfg->winp[i] = pci_remap_cfgspace(cfgres->start + i * bsz, bsz); if (!cfg->winp[i]) goto err_exit_iomap; } } else { cfg->win = pci_remap_cfgspace(cfgres->start, bus_range * bsz); if (!cfg->win) goto err_exit_iomap; } if (ops->init) { err = ops->init(cfg); if (err) goto err_exit; } dev_info(dev, "ECAM at %pR for %pR\n", &cfg->res, &cfg->busr); return cfg; err_exit_iomap: dev_err(dev, "ECAM ioremap failed\n"); err_exit_malloc: err = -ENOMEM; err_exit: pci_ecam_free(cfg); return ERR_PTR(err); } void pci_ecam_free(struct pci_config_window *cfg) { int i; if (per_bus_mapping) { if (cfg->winp) { for (i = 0; i < resource_size(&cfg->busr); i++) if (cfg->winp[i]) iounmap(cfg->winp[i]); kfree(cfg->winp); } } else { if (cfg->win) iounmap(cfg->win); } if (cfg->res.parent) release_resource(&cfg->res); kfree(cfg); } /* * Function to implement the pci_ops ->map_bus method */ void __iomem *pci_ecam_map_bus(struct pci_bus *bus, unsigned int devfn, int where) { struct pci_config_window *cfg = bus->sysdata; unsigned int devfn_shift = cfg->ops->bus_shift - 8; unsigned int busn = bus->number; void __iomem *base; if (busn < cfg->busr.start || busn > cfg->busr.end) return NULL; busn -= cfg->busr.start; if (per_bus_mapping) base = cfg->winp[busn]; else base = cfg->win + (busn << cfg->ops->bus_shift); return base + (devfn << devfn_shift) + where; } /* ECAM ops */ struct pci_ecam_ops pci_generic_ecam_ops = { .bus_shift = 20, .pci_ops = { .map_bus = pci_ecam_map_bus, .read = pci_generic_config_read, .write = pci_generic_config_write, } }; #if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS) /* ECAM ops for 32-bit access only (non-compliant) */ struct pci_ecam_ops pci_32b_ops = { .bus_shift = 20, .pci_ops = { .map_bus = pci_ecam_map_bus, .read = pci_generic_config_read32, .write = pci_generic_config_write32, } }; #endif |