1 /* 2 * Support PCI IO workaround 3 * 4 * Copyright (C) 2006 Benjamin Herrenschmidt <benh@kernel.crashing.org> 5 * IBM, Corp. 6 * (C) Copyright 2007-2008 TOSHIBA CORPORATION 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 #undef DEBUG 13 14 #include <linux/kernel.h> 15 #include <linux/sched.h> /* for init_mm */ 16 17 #include <asm/io.h> 18 #include <asm/machdep.h> 19 #include <asm/pgtable.h> 20 #include <asm/ppc-pci.h> 21 #include <asm/io-workarounds.h> 22 23 #define IOWA_MAX_BUS 8 24 25 static struct iowa_bus iowa_busses[IOWA_MAX_BUS]; 26 static unsigned int iowa_bus_count; 27 28 static struct iowa_bus *iowa_pci_find(unsigned long vaddr, unsigned long paddr) 29 { 30 int i, j; 31 struct resource *res; 32 unsigned long vstart, vend; 33 34 for (i = 0; i < iowa_bus_count; i++) { 35 struct iowa_bus *bus = &iowa_busses[i]; 36 struct pci_controller *phb = bus->phb; 37 38 if (vaddr) { 39 vstart = (unsigned long)phb->io_base_virt; 40 vend = vstart + phb->pci_io_size - 1; 41 if ((vaddr >= vstart) && (vaddr <= vend)) 42 return bus; 43 } 44 45 if (paddr) 46 for (j = 0; j < 3; j++) { 47 res = &phb->mem_resources[j]; 48 if (paddr >= res->start && paddr <= res->end) 49 return bus; 50 } 51 } 52 53 return NULL; 54 } 55 56 struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr) 57 { 58 unsigned hugepage_shift; 59 struct iowa_bus *bus; 60 int token; 61 62 token = PCI_GET_ADDR_TOKEN(addr); 63 64 if (token && token <= iowa_bus_count) 65 bus = &iowa_busses[token - 1]; 66 else { 67 unsigned long vaddr, paddr; 68 pte_t *ptep; 69 70 vaddr = (unsigned long)PCI_FIX_ADDR(addr); 71 if (vaddr < PHB_IO_BASE || vaddr >= PHB_IO_END) 72 return NULL; 73 74 ptep = find_linux_pte_or_hugepte(init_mm.pgd, vaddr, 75 &hugepage_shift); 76 if (ptep == NULL) 77 paddr = 0; 78 else { 79 /* 80 * we don't have hugepages backing iomem 81 */ 82 WARN_ON(hugepage_shift); 83 paddr = pte_pfn(*ptep) << PAGE_SHIFT; 84 } 85 bus = iowa_pci_find(vaddr, paddr); 86 87 if (bus == NULL) 88 return NULL; 89 } 90 91 return bus; 92 } 93 94 struct iowa_bus *iowa_pio_find_bus(unsigned long port) 95 { 96 unsigned long vaddr = (unsigned long)pci_io_base + port; 97 return iowa_pci_find(vaddr, 0); 98 } 99 100 101 #define DEF_PCI_AC_RET(name, ret, at, al, space, aa) \ 102 static ret iowa_##name at \ 103 { \ 104 struct iowa_bus *bus; \ 105 bus = iowa_##space##_find_bus(aa); \ 106 if (bus && bus->ops && bus->ops->name) \ 107 return bus->ops->name al; \ 108 return __do_##name al; \ 109 } 110 111 #define DEF_PCI_AC_NORET(name, at, al, space, aa) \ 112 static void iowa_##name at \ 113 { \ 114 struct iowa_bus *bus; \ 115 bus = iowa_##space##_find_bus(aa); \ 116 if (bus && bus->ops && bus->ops->name) { \ 117 bus->ops->name al; \ 118 return; \ 119 } \ 120 __do_##name al; \ 121 } 122 123 #include <asm/io-defs.h> 124 125 #undef DEF_PCI_AC_RET 126 #undef DEF_PCI_AC_NORET 127 128 static const struct ppc_pci_io iowa_pci_io = { 129 130 #define DEF_PCI_AC_RET(name, ret, at, al, space, aa) .name = iowa_##name, 131 #define DEF_PCI_AC_NORET(name, at, al, space, aa) .name = iowa_##name, 132 133 #include <asm/io-defs.h> 134 135 #undef DEF_PCI_AC_RET 136 #undef DEF_PCI_AC_NORET 137 138 }; 139 140 static void __iomem *iowa_ioremap(phys_addr_t addr, unsigned long size, 141 unsigned long flags, void *caller) 142 { 143 struct iowa_bus *bus; 144 void __iomem *res = __ioremap_caller(addr, size, flags, caller); 145 int busno; 146 147 bus = iowa_pci_find(0, (unsigned long)addr); 148 if (bus != NULL) { 149 busno = bus - iowa_busses; 150 PCI_SET_ADDR_TOKEN(res, busno + 1); 151 } 152 return res; 153 } 154 155 /* Enable IO workaround */ 156 static void io_workaround_init(void) 157 { 158 static int io_workaround_inited; 159 160 if (io_workaround_inited) 161 return; 162 ppc_pci_io = iowa_pci_io; 163 ppc_md.ioremap = iowa_ioremap; 164 io_workaround_inited = 1; 165 } 166 167 /* Register new bus to support workaround */ 168 void iowa_register_bus(struct pci_controller *phb, struct ppc_pci_io *ops, 169 int (*initfunc)(struct iowa_bus *, void *), void *data) 170 { 171 struct iowa_bus *bus; 172 struct device_node *np = phb->dn; 173 174 io_workaround_init(); 175 176 if (iowa_bus_count >= IOWA_MAX_BUS) { 177 pr_err("IOWA:Too many pci bridges, " 178 "workarounds disabled for %s\n", np->full_name); 179 return; 180 } 181 182 bus = &iowa_busses[iowa_bus_count]; 183 bus->phb = phb; 184 bus->ops = ops; 185 bus->private = data; 186 187 if (initfunc) 188 if ((*initfunc)(bus, data)) 189 return; 190 191 iowa_bus_count++; 192 193 pr_debug("IOWA:[%d]Add bus, %s.\n", iowa_bus_count-1, np->full_name); 194 } 195 196