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 struct iowa_bus *bus; 59 int token; 60 61 token = PCI_GET_ADDR_TOKEN(addr); 62 63 if (token && token <= iowa_bus_count) 64 bus = &iowa_busses[token - 1]; 65 else { 66 unsigned long vaddr, paddr; 67 pte_t *ptep; 68 69 vaddr = (unsigned long)PCI_FIX_ADDR(addr); 70 if (vaddr < PHB_IO_BASE || vaddr >= PHB_IO_END) 71 return NULL; 72 73 ptep = find_linux_pte(init_mm.pgd, vaddr); 74 if (ptep == NULL) 75 paddr = 0; 76 else 77 paddr = pte_pfn(*ptep) << PAGE_SHIFT; 78 bus = iowa_pci_find(vaddr, paddr); 79 80 if (bus == NULL) 81 return NULL; 82 } 83 84 return bus; 85 } 86 87 struct iowa_bus *iowa_pio_find_bus(unsigned long port) 88 { 89 unsigned long vaddr = (unsigned long)pci_io_base + port; 90 return iowa_pci_find(vaddr, 0); 91 } 92 93 94 #define DEF_PCI_AC_RET(name, ret, at, al, space, aa) \ 95 static ret iowa_##name at \ 96 { \ 97 struct iowa_bus *bus; \ 98 bus = iowa_##space##_find_bus(aa); \ 99 if (bus && bus->ops && bus->ops->name) \ 100 return bus->ops->name al; \ 101 return __do_##name al; \ 102 } 103 104 #define DEF_PCI_AC_NORET(name, at, al, space, aa) \ 105 static void iowa_##name at \ 106 { \ 107 struct iowa_bus *bus; \ 108 bus = iowa_##space##_find_bus(aa); \ 109 if (bus && bus->ops && bus->ops->name) { \ 110 bus->ops->name al; \ 111 return; \ 112 } \ 113 __do_##name al; \ 114 } 115 116 #include <asm/io-defs.h> 117 118 #undef DEF_PCI_AC_RET 119 #undef DEF_PCI_AC_NORET 120 121 static const struct ppc_pci_io iowa_pci_io = { 122 123 #define DEF_PCI_AC_RET(name, ret, at, al, space, aa) .name = iowa_##name, 124 #define DEF_PCI_AC_NORET(name, at, al, space, aa) .name = iowa_##name, 125 126 #include <asm/io-defs.h> 127 128 #undef DEF_PCI_AC_RET 129 #undef DEF_PCI_AC_NORET 130 131 }; 132 133 static void __iomem *iowa_ioremap(phys_addr_t addr, unsigned long size, 134 unsigned long flags, void *caller) 135 { 136 struct iowa_bus *bus; 137 void __iomem *res = __ioremap_caller(addr, size, flags, caller); 138 int busno; 139 140 bus = iowa_pci_find(0, (unsigned long)addr); 141 if (bus != NULL) { 142 busno = bus - iowa_busses; 143 PCI_SET_ADDR_TOKEN(res, busno + 1); 144 } 145 return res; 146 } 147 148 /* Enable IO workaround */ 149 static void io_workaround_init(void) 150 { 151 static int io_workaround_inited; 152 153 if (io_workaround_inited) 154 return; 155 ppc_pci_io = iowa_pci_io; 156 ppc_md.ioremap = iowa_ioremap; 157 io_workaround_inited = 1; 158 } 159 160 /* Register new bus to support workaround */ 161 void iowa_register_bus(struct pci_controller *phb, struct ppc_pci_io *ops, 162 int (*initfunc)(struct iowa_bus *, void *), void *data) 163 { 164 struct iowa_bus *bus; 165 struct device_node *np = phb->dn; 166 167 io_workaround_init(); 168 169 if (iowa_bus_count >= IOWA_MAX_BUS) { 170 pr_err("IOWA:Too many pci bridges, " 171 "workarounds disabled for %s\n", np->full_name); 172 return; 173 } 174 175 bus = &iowa_busses[iowa_bus_count]; 176 bus->phb = phb; 177 bus->ops = ops; 178 bus->private = data; 179 180 if (initfunc) 181 if ((*initfunc)(bus, data)) 182 return; 183 184 iowa_bus_count++; 185 186 pr_debug("IOWA:[%d]Add bus, %s.\n", iowa_bus_count-1, np->full_name); 187 } 188 189