1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * ioport.c: Simple io mapping allocator. 4 * 5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) 6 * Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx) 7 * 8 * 1996: sparc_free_io, 1999: ioremap()/iounmap() by Pete Zaitcev. 9 * 10 * 2000/01/29 11 * <rth> zait: as long as pci_alloc_consistent produces something addressable, 12 * things are ok. 13 * <zaitcev> rth: no, it is relevant, because get_free_pages returns you a 14 * pointer into the big page mapping 15 * <rth> zait: so what? 16 * <rth> zait: remap_it_my_way(virt_to_phys(get_free_page())) 17 * <zaitcev> Hmm 18 * <zaitcev> Suppose I did this remap_it_my_way(virt_to_phys(get_free_page())). 19 * So far so good. 20 * <zaitcev> Now, driver calls pci_free_consistent(with result of 21 * remap_it_my_way()). 22 * <zaitcev> How do you find the address to pass to free_pages()? 23 * <rth> zait: walk the page tables? It's only two or three level after all. 24 * <rth> zait: you have to walk them anyway to remove the mapping. 25 * <zaitcev> Hmm 26 * <zaitcev> Sounds reasonable 27 */ 28 29 #include <linux/module.h> 30 #include <linux/sched.h> 31 #include <linux/kernel.h> 32 #include <linux/errno.h> 33 #include <linux/types.h> 34 #include <linux/ioport.h> 35 #include <linux/mm.h> 36 #include <linux/slab.h> 37 #include <linux/pci.h> /* struct pci_dev */ 38 #include <linux/proc_fs.h> 39 #include <linux/seq_file.h> 40 #include <linux/scatterlist.h> 41 #include <linux/dma-map-ops.h> 42 #include <linux/of_device.h> 43 44 #include <asm/io.h> 45 #include <asm/vaddrs.h> 46 #include <asm/oplib.h> 47 #include <asm/prom.h> 48 #include <asm/page.h> 49 #include <asm/pgalloc.h> 50 #include <asm/dma.h> 51 #include <asm/iommu.h> 52 #include <asm/io-unit.h> 53 #include <asm/leon.h> 54 55 static void __iomem *_sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz); 56 static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys, 57 unsigned long size, char *name); 58 static void _sparc_free_io(struct resource *res); 59 60 static void register_proc_sparc_ioport(void); 61 62 /* This points to the next to use virtual memory for DVMA mappings */ 63 static struct resource _sparc_dvma = { 64 .name = "sparc_dvma", .start = DVMA_VADDR, .end = DVMA_END - 1 65 }; 66 /* This points to the start of I/O mappings, cluable from outside. */ 67 /*ext*/ struct resource sparc_iomap = { 68 .name = "sparc_iomap", .start = IOBASE_VADDR, .end = IOBASE_END - 1 69 }; 70 71 /* 72 * Our mini-allocator... 73 * Boy this is gross! We need it because we must map I/O for 74 * timers and interrupt controller before the kmalloc is available. 75 */ 76 77 #define XNMLN 15 78 #define XNRES 10 /* SS-10 uses 8 */ 79 80 struct xresource { 81 struct resource xres; /* Must be first */ 82 int xflag; /* 1 == used */ 83 char xname[XNMLN+1]; 84 }; 85 86 static struct xresource xresv[XNRES]; 87 88 static struct xresource *xres_alloc(void) { 89 struct xresource *xrp; 90 int n; 91 92 xrp = xresv; 93 for (n = 0; n < XNRES; n++) { 94 if (xrp->xflag == 0) { 95 xrp->xflag = 1; 96 return xrp; 97 } 98 xrp++; 99 } 100 return NULL; 101 } 102 103 static void xres_free(struct xresource *xrp) { 104 xrp->xflag = 0; 105 } 106 107 /* 108 * These are typically used in PCI drivers 109 * which are trying to be cross-platform. 110 * 111 * Bus type is always zero on IIep. 112 */ 113 void __iomem *ioremap(phys_addr_t offset, size_t size) 114 { 115 char name[14]; 116 117 sprintf(name, "phys_%08x", (u32)offset); 118 return _sparc_alloc_io(0, (unsigned long)offset, size, name); 119 } 120 EXPORT_SYMBOL(ioremap); 121 122 /* 123 * Complementary to ioremap(). 124 */ 125 void iounmap(volatile void __iomem *virtual) 126 { 127 unsigned long vaddr = (unsigned long) virtual & PAGE_MASK; 128 struct resource *res; 129 130 /* 131 * XXX Too slow. Can have 8192 DVMA pages on sun4m in the worst case. 132 * This probably warrants some sort of hashing. 133 */ 134 if ((res = lookup_resource(&sparc_iomap, vaddr)) == NULL) { 135 printk("free_io/iounmap: cannot free %lx\n", vaddr); 136 return; 137 } 138 _sparc_free_io(res); 139 140 if ((char *)res >= (char*)xresv && (char *)res < (char *)&xresv[XNRES]) { 141 xres_free((struct xresource *)res); 142 } else { 143 kfree(res); 144 } 145 } 146 EXPORT_SYMBOL(iounmap); 147 148 void __iomem *of_ioremap(struct resource *res, unsigned long offset, 149 unsigned long size, char *name) 150 { 151 return _sparc_alloc_io(res->flags & 0xF, 152 res->start + offset, 153 size, name); 154 } 155 EXPORT_SYMBOL(of_ioremap); 156 157 void of_iounmap(struct resource *res, void __iomem *base, unsigned long size) 158 { 159 iounmap(base); 160 } 161 EXPORT_SYMBOL(of_iounmap); 162 163 /* 164 * Meat of mapping 165 */ 166 static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys, 167 unsigned long size, char *name) 168 { 169 static int printed_full; 170 struct xresource *xres; 171 struct resource *res; 172 char *tack; 173 int tlen; 174 void __iomem *va; /* P3 diag */ 175 176 if (name == NULL) name = "???"; 177 178 if ((xres = xres_alloc()) != NULL) { 179 tack = xres->xname; 180 res = &xres->xres; 181 } else { 182 if (!printed_full) { 183 printk("ioremap: done with statics, switching to malloc\n"); 184 printed_full = 1; 185 } 186 tlen = strlen(name); 187 tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL); 188 if (tack == NULL) return NULL; 189 memset(tack, 0, sizeof(struct resource)); 190 res = (struct resource *) tack; 191 tack += sizeof (struct resource); 192 } 193 194 strlcpy(tack, name, XNMLN+1); 195 res->name = tack; 196 197 va = _sparc_ioremap(res, busno, phys, size); 198 /* printk("ioremap(0x%x:%08lx[0x%lx])=%p\n", busno, phys, size, va); */ /* P3 diag */ 199 return va; 200 } 201 202 /* 203 */ 204 static void __iomem * 205 _sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz) 206 { 207 unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK); 208 209 if (allocate_resource(&sparc_iomap, res, 210 (offset + sz + PAGE_SIZE-1) & PAGE_MASK, 211 sparc_iomap.start, sparc_iomap.end, PAGE_SIZE, NULL, NULL) != 0) { 212 /* Usually we cannot see printks in this case. */ 213 prom_printf("alloc_io_res(%s): cannot occupy\n", 214 (res->name != NULL)? res->name: "???"); 215 prom_halt(); 216 } 217 218 pa &= PAGE_MASK; 219 srmmu_mapiorange(bus, pa, res->start, resource_size(res)); 220 221 return (void __iomem *)(unsigned long)(res->start + offset); 222 } 223 224 /* 225 * Complementary to _sparc_ioremap(). 226 */ 227 static void _sparc_free_io(struct resource *res) 228 { 229 unsigned long plen; 230 231 plen = resource_size(res); 232 BUG_ON((plen & (PAGE_SIZE-1)) != 0); 233 srmmu_unmapiorange(res->start, plen); 234 release_resource(res); 235 } 236 237 unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len) 238 { 239 struct resource *res; 240 241 res = kzalloc(sizeof(*res), GFP_KERNEL); 242 if (!res) 243 return 0; 244 res->name = dev->of_node->full_name; 245 246 if (allocate_resource(&_sparc_dvma, res, len, _sparc_dvma.start, 247 _sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) { 248 printk("%s: cannot occupy 0x%zx", __func__, len); 249 kfree(res); 250 return 0; 251 } 252 253 return res->start; 254 } 255 256 bool sparc_dma_free_resource(void *cpu_addr, size_t size) 257 { 258 unsigned long addr = (unsigned long)cpu_addr; 259 struct resource *res; 260 261 res = lookup_resource(&_sparc_dvma, addr); 262 if (!res) { 263 printk("%s: cannot free %p\n", __func__, cpu_addr); 264 return false; 265 } 266 267 if ((addr & (PAGE_SIZE - 1)) != 0) { 268 printk("%s: unaligned va %p\n", __func__, cpu_addr); 269 return false; 270 } 271 272 size = PAGE_ALIGN(size); 273 if (resource_size(res) != size) { 274 printk("%s: region 0x%lx asked 0x%zx\n", 275 __func__, (long)resource_size(res), size); 276 return false; 277 } 278 279 release_resource(res); 280 kfree(res); 281 return true; 282 } 283 284 #ifdef CONFIG_SBUS 285 286 void sbus_set_sbus64(struct device *dev, int x) 287 { 288 printk("sbus_set_sbus64: unsupported\n"); 289 } 290 EXPORT_SYMBOL(sbus_set_sbus64); 291 292 static int __init sparc_register_ioport(void) 293 { 294 register_proc_sparc_ioport(); 295 296 return 0; 297 } 298 299 arch_initcall(sparc_register_ioport); 300 301 #endif /* CONFIG_SBUS */ 302 303 /* 304 * IIep is write-through, not flushing on cpu to device transfer. 305 * 306 * On LEON systems without cache snooping, the entire D-CACHE must be flushed to 307 * make DMA to cacheable memory coherent. 308 */ 309 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, 310 enum dma_data_direction dir) 311 { 312 if (dir != PCI_DMA_TODEVICE && 313 sparc_cpu_model == sparc_leon && 314 !sparc_leon3_snooping_enabled()) 315 leon_flush_dcache_all(); 316 } 317 318 #ifdef CONFIG_PROC_FS 319 320 static int sparc_io_proc_show(struct seq_file *m, void *v) 321 { 322 struct resource *root = m->private, *r; 323 const char *nm; 324 325 for (r = root->child; r != NULL; r = r->sibling) { 326 if ((nm = r->name) == NULL) nm = "???"; 327 seq_printf(m, "%016llx-%016llx: %s\n", 328 (unsigned long long)r->start, 329 (unsigned long long)r->end, nm); 330 } 331 332 return 0; 333 } 334 #endif /* CONFIG_PROC_FS */ 335 336 static void register_proc_sparc_ioport(void) 337 { 338 #ifdef CONFIG_PROC_FS 339 proc_create_single_data("io_map", 0, NULL, sparc_io_proc_show, 340 &sparc_iomap); 341 proc_create_single_data("dvma_map", 0, NULL, sparc_io_proc_show, 342 &_sparc_dvma); 343 #endif 344 } 345