1 /* 2 * arch/x86/pci/sta2x11-fixup.c 3 * glue code for lib/swiotlb.c and DMA translation between STA2x11 4 * AMBA memory mapping and the X86 memory mapping 5 * 6 * ST Microelectronics ConneXt (STA2X11/STA2X10) 7 * 8 * Copyright (c) 2010-2011 Wind River Systems, Inc. 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 17 * See the GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 22 * 23 */ 24 25 #include <linux/pci.h> 26 #include <linux/pci_ids.h> 27 #include <linux/export.h> 28 #include <linux/list.h> 29 30 #define STA2X11_SWIOTLB_SIZE (4*1024*1024) 31 extern int swiotlb_late_init_with_default_size(size_t default_size); 32 33 /* 34 * We build a list of bus numbers that are under the ConneXt. The 35 * main bridge hosts 4 busses, which are the 4 endpoints, in order. 36 */ 37 #define STA2X11_NR_EP 4 /* 0..3 included */ 38 #define STA2X11_NR_FUNCS 8 /* 0..7 included */ 39 #define STA2X11_AMBA_SIZE (512 << 20) 40 41 struct sta2x11_ahb_regs { /* saved during suspend */ 42 u32 base, pexlbase, pexhbase, crw; 43 }; 44 45 struct sta2x11_mapping { 46 u32 amba_base; 47 int is_suspended; 48 struct sta2x11_ahb_regs regs[STA2X11_NR_FUNCS]; 49 }; 50 51 struct sta2x11_instance { 52 struct list_head list; 53 int bus0; 54 struct sta2x11_mapping map[STA2X11_NR_EP]; 55 }; 56 57 static LIST_HEAD(sta2x11_instance_list); 58 59 /* At probe time, record new instances of this bridge (likely one only) */ 60 static void sta2x11_new_instance(struct pci_dev *pdev) 61 { 62 struct sta2x11_instance *instance; 63 64 instance = kzalloc(sizeof(*instance), GFP_ATOMIC); 65 if (!instance) 66 return; 67 /* This has a subordinate bridge, with 4 more-subordinate ones */ 68 instance->bus0 = pdev->subordinate->number + 1; 69 70 if (list_empty(&sta2x11_instance_list)) { 71 int size = STA2X11_SWIOTLB_SIZE; 72 /* First instance: register your own swiotlb area */ 73 dev_info(&pdev->dev, "Using SWIOTLB (size %i)\n", size); 74 if (swiotlb_late_init_with_default_size(size)) 75 dev_emerg(&pdev->dev, "init swiotlb failed\n"); 76 } 77 list_add(&instance->list, &sta2x11_instance_list); 78 } 79 DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, 0xcc17, sta2x11_new_instance); 80 81 /* 82 * Utility functions used in this file from below 83 */ 84 static struct sta2x11_instance *sta2x11_pdev_to_instance(struct pci_dev *pdev) 85 { 86 struct sta2x11_instance *instance; 87 int ep; 88 89 list_for_each_entry(instance, &sta2x11_instance_list, list) { 90 ep = pdev->bus->number - instance->bus0; 91 if (ep >= 0 && ep < STA2X11_NR_EP) 92 return instance; 93 } 94 return NULL; 95 } 96 97 static int sta2x11_pdev_to_ep(struct pci_dev *pdev) 98 { 99 struct sta2x11_instance *instance; 100 101 instance = sta2x11_pdev_to_instance(pdev); 102 if (!instance) 103 return -1; 104 105 return pdev->bus->number - instance->bus0; 106 } 107 108 static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev) 109 { 110 struct sta2x11_instance *instance; 111 int ep; 112 113 instance = sta2x11_pdev_to_instance(pdev); 114 if (!instance) 115 return NULL; 116 ep = sta2x11_pdev_to_ep(pdev); 117 return instance->map + ep; 118 } 119 120 /* This is exported, as some devices need to access the MFD registers */ 121 struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev) 122 { 123 return sta2x11_pdev_to_instance(pdev); 124 } 125 EXPORT_SYMBOL(sta2x11_get_instance); 126 127 128 /** 129 * p2a - Translate physical address to STA2x11 AMBA address, 130 * used for DMA transfers to STA2x11 131 * @p: Physical address 132 * @pdev: PCI device (must be hosted within the connext) 133 */ 134 static dma_addr_t p2a(dma_addr_t p, struct pci_dev *pdev) 135 { 136 struct sta2x11_mapping *map; 137 dma_addr_t a; 138 139 map = sta2x11_pdev_to_mapping(pdev); 140 a = p + map->amba_base; 141 return a; 142 } 143 144 /** 145 * a2p - Translate STA2x11 AMBA address to physical address 146 * used for DMA transfers from STA2x11 147 * @a: STA2x11 AMBA address 148 * @pdev: PCI device (must be hosted within the connext) 149 */ 150 static dma_addr_t a2p(dma_addr_t a, struct pci_dev *pdev) 151 { 152 struct sta2x11_mapping *map; 153 dma_addr_t p; 154 155 map = sta2x11_pdev_to_mapping(pdev); 156 p = a - map->amba_base; 157 return p; 158 } 159 160 /** 161 * sta2x11_swiotlb_alloc_coherent - Allocate swiotlb bounce buffers 162 * returns virtual address. This is the only "special" function here. 163 * @dev: PCI device 164 * @size: Size of the buffer 165 * @dma_handle: DMA address 166 * @flags: memory flags 167 */ 168 static void *sta2x11_swiotlb_alloc_coherent(struct device *dev, 169 size_t size, 170 dma_addr_t *dma_handle, 171 gfp_t flags, 172 unsigned long attrs) 173 { 174 void *vaddr; 175 176 vaddr = x86_swiotlb_alloc_coherent(dev, size, dma_handle, flags, attrs); 177 *dma_handle = p2a(*dma_handle, to_pci_dev(dev)); 178 return vaddr; 179 } 180 181 /* We have our own dma_ops: the same as swiotlb but from alloc (above) */ 182 static struct dma_map_ops sta2x11_dma_ops = { 183 .alloc = sta2x11_swiotlb_alloc_coherent, 184 .free = x86_swiotlb_free_coherent, 185 .map_page = swiotlb_map_page, 186 .unmap_page = swiotlb_unmap_page, 187 .map_sg = swiotlb_map_sg_attrs, 188 .unmap_sg = swiotlb_unmap_sg_attrs, 189 .sync_single_for_cpu = swiotlb_sync_single_for_cpu, 190 .sync_single_for_device = swiotlb_sync_single_for_device, 191 .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu, 192 .sync_sg_for_device = swiotlb_sync_sg_for_device, 193 .mapping_error = swiotlb_dma_mapping_error, 194 .dma_supported = NULL, /* FIXME: we should use this instead! */ 195 }; 196 197 /* At setup time, we use our own ops if the device is a ConneXt one */ 198 static void sta2x11_setup_pdev(struct pci_dev *pdev) 199 { 200 struct sta2x11_instance *instance = sta2x11_pdev_to_instance(pdev); 201 202 if (!instance) /* either a sta2x11 bridge or another ST device */ 203 return; 204 pci_set_consistent_dma_mask(pdev, STA2X11_AMBA_SIZE - 1); 205 pci_set_dma_mask(pdev, STA2X11_AMBA_SIZE - 1); 206 pdev->dev.archdata.dma_ops = &sta2x11_dma_ops; 207 208 /* We must enable all devices as master, for audio DMA to work */ 209 pci_set_master(pdev); 210 } 211 DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_setup_pdev); 212 213 /* 214 * The following three functions are exported (used in swiotlb: FIXME) 215 */ 216 /** 217 * dma_capable - Check if device can manage DMA transfers (FIXME: kill it) 218 * @dev: device for a PCI device 219 * @addr: DMA address 220 * @size: DMA size 221 */ 222 bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) 223 { 224 struct sta2x11_mapping *map; 225 226 if (dev->archdata.dma_ops != &sta2x11_dma_ops) { 227 if (!dev->dma_mask) 228 return false; 229 return addr + size - 1 <= *dev->dma_mask; 230 } 231 232 map = sta2x11_pdev_to_mapping(to_pci_dev(dev)); 233 234 if (!map || (addr < map->amba_base)) 235 return false; 236 if (addr + size >= map->amba_base + STA2X11_AMBA_SIZE) { 237 return false; 238 } 239 240 return true; 241 } 242 243 /** 244 * phys_to_dma - Return the DMA AMBA address used for this STA2x11 device 245 * @dev: device for a PCI device 246 * @paddr: Physical address 247 */ 248 dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) 249 { 250 if (dev->archdata.dma_ops != &sta2x11_dma_ops) 251 return paddr; 252 return p2a(paddr, to_pci_dev(dev)); 253 } 254 255 /** 256 * dma_to_phys - Return the physical address used for this STA2x11 DMA address 257 * @dev: device for a PCI device 258 * @daddr: STA2x11 AMBA DMA address 259 */ 260 phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr) 261 { 262 if (dev->archdata.dma_ops != &sta2x11_dma_ops) 263 return daddr; 264 return a2p(daddr, to_pci_dev(dev)); 265 } 266 267 268 /* 269 * At boot we must set up the mappings for the pcie-to-amba bridge. 270 * It involves device access, and the same happens at suspend/resume time 271 */ 272 273 #define AHB_MAPB 0xCA4 274 #define AHB_CRW(i) (AHB_MAPB + 0 + (i) * 0x10) 275 #define AHB_CRW_SZMASK 0xfffffc00UL 276 #define AHB_CRW_ENABLE (1 << 0) 277 #define AHB_CRW_WTYPE_MEM (2 << 1) 278 #define AHB_CRW_ROE (1UL << 3) /* Relax Order Ena */ 279 #define AHB_CRW_NSE (1UL << 4) /* No Snoop Enable */ 280 #define AHB_BASE(i) (AHB_MAPB + 4 + (i) * 0x10) 281 #define AHB_PEXLBASE(i) (AHB_MAPB + 8 + (i) * 0x10) 282 #define AHB_PEXHBASE(i) (AHB_MAPB + 12 + (i) * 0x10) 283 284 /* At probe time, enable mapping for each endpoint, using the pdev */ 285 static void sta2x11_map_ep(struct pci_dev *pdev) 286 { 287 struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev); 288 int i; 289 290 if (!map) 291 return; 292 pci_read_config_dword(pdev, AHB_BASE(0), &map->amba_base); 293 294 /* Configure AHB mapping */ 295 pci_write_config_dword(pdev, AHB_PEXLBASE(0), 0); 296 pci_write_config_dword(pdev, AHB_PEXHBASE(0), 0); 297 pci_write_config_dword(pdev, AHB_CRW(0), STA2X11_AMBA_SIZE | 298 AHB_CRW_WTYPE_MEM | AHB_CRW_ENABLE); 299 300 /* Disable all the other windows */ 301 for (i = 1; i < STA2X11_NR_FUNCS; i++) 302 pci_write_config_dword(pdev, AHB_CRW(i), 0); 303 304 dev_info(&pdev->dev, 305 "sta2x11: Map EP %i: AMBA address %#8x-%#8x\n", 306 sta2x11_pdev_to_ep(pdev), map->amba_base, 307 map->amba_base + STA2X11_AMBA_SIZE - 1); 308 } 309 DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_map_ep); 310 311 #ifdef CONFIG_PM /* Some register values must be saved and restored */ 312 313 static void suspend_mapping(struct pci_dev *pdev) 314 { 315 struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev); 316 int i; 317 318 if (!map) 319 return; 320 321 if (map->is_suspended) 322 return; 323 map->is_suspended = 1; 324 325 /* Save all window configs */ 326 for (i = 0; i < STA2X11_NR_FUNCS; i++) { 327 struct sta2x11_ahb_regs *regs = map->regs + i; 328 329 pci_read_config_dword(pdev, AHB_BASE(i), ®s->base); 330 pci_read_config_dword(pdev, AHB_PEXLBASE(i), ®s->pexlbase); 331 pci_read_config_dword(pdev, AHB_PEXHBASE(i), ®s->pexhbase); 332 pci_read_config_dword(pdev, AHB_CRW(i), ®s->crw); 333 } 334 } 335 DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, suspend_mapping); 336 337 static void resume_mapping(struct pci_dev *pdev) 338 { 339 struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev); 340 int i; 341 342 if (!map) 343 return; 344 345 346 if (!map->is_suspended) 347 goto out; 348 map->is_suspended = 0; 349 350 /* Restore all window configs */ 351 for (i = 0; i < STA2X11_NR_FUNCS; i++) { 352 struct sta2x11_ahb_regs *regs = map->regs + i; 353 354 pci_write_config_dword(pdev, AHB_BASE(i), regs->base); 355 pci_write_config_dword(pdev, AHB_PEXLBASE(i), regs->pexlbase); 356 pci_write_config_dword(pdev, AHB_PEXHBASE(i), regs->pexhbase); 357 pci_write_config_dword(pdev, AHB_CRW(i), regs->crw); 358 } 359 out: 360 pci_set_master(pdev); /* Like at boot, enable master on all devices */ 361 } 362 DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, resume_mapping); 363 364 #endif /* CONFIG_PM */ 365