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 #include <linux/dma-direct.h> 30 #include <asm/iommu.h> 31 32 #define STA2X11_SWIOTLB_SIZE (4*1024*1024) 33 extern int swiotlb_late_init_with_default_size(size_t default_size); 34 35 /* 36 * We build a list of bus numbers that are under the ConneXt. The 37 * main bridge hosts 4 busses, which are the 4 endpoints, in order. 38 */ 39 #define STA2X11_NR_EP 4 /* 0..3 included */ 40 #define STA2X11_NR_FUNCS 8 /* 0..7 included */ 41 #define STA2X11_AMBA_SIZE (512 << 20) 42 43 struct sta2x11_ahb_regs { /* saved during suspend */ 44 u32 base, pexlbase, pexhbase, crw; 45 }; 46 47 struct sta2x11_mapping { 48 u32 amba_base; 49 int is_suspended; 50 struct sta2x11_ahb_regs regs[STA2X11_NR_FUNCS]; 51 }; 52 53 struct sta2x11_instance { 54 struct list_head list; 55 int bus0; 56 struct sta2x11_mapping map[STA2X11_NR_EP]; 57 }; 58 59 static LIST_HEAD(sta2x11_instance_list); 60 61 /* At probe time, record new instances of this bridge (likely one only) */ 62 static void sta2x11_new_instance(struct pci_dev *pdev) 63 { 64 struct sta2x11_instance *instance; 65 66 instance = kzalloc(sizeof(*instance), GFP_ATOMIC); 67 if (!instance) 68 return; 69 /* This has a subordinate bridge, with 4 more-subordinate ones */ 70 instance->bus0 = pdev->subordinate->number + 1; 71 72 if (list_empty(&sta2x11_instance_list)) { 73 int size = STA2X11_SWIOTLB_SIZE; 74 /* First instance: register your own swiotlb area */ 75 dev_info(&pdev->dev, "Using SWIOTLB (size %i)\n", size); 76 if (swiotlb_late_init_with_default_size(size)) 77 dev_emerg(&pdev->dev, "init swiotlb failed\n"); 78 } 79 list_add(&instance->list, &sta2x11_instance_list); 80 } 81 DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, 0xcc17, sta2x11_new_instance); 82 83 /* 84 * Utility functions used in this file from below 85 */ 86 static struct sta2x11_instance *sta2x11_pdev_to_instance(struct pci_dev *pdev) 87 { 88 struct sta2x11_instance *instance; 89 int ep; 90 91 list_for_each_entry(instance, &sta2x11_instance_list, list) { 92 ep = pdev->bus->number - instance->bus0; 93 if (ep >= 0 && ep < STA2X11_NR_EP) 94 return instance; 95 } 96 return NULL; 97 } 98 99 static int sta2x11_pdev_to_ep(struct pci_dev *pdev) 100 { 101 struct sta2x11_instance *instance; 102 103 instance = sta2x11_pdev_to_instance(pdev); 104 if (!instance) 105 return -1; 106 107 return pdev->bus->number - instance->bus0; 108 } 109 110 static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev) 111 { 112 struct sta2x11_instance *instance; 113 int ep; 114 115 instance = sta2x11_pdev_to_instance(pdev); 116 if (!instance) 117 return NULL; 118 ep = sta2x11_pdev_to_ep(pdev); 119 return instance->map + ep; 120 } 121 122 /* This is exported, as some devices need to access the MFD registers */ 123 struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev) 124 { 125 return sta2x11_pdev_to_instance(pdev); 126 } 127 EXPORT_SYMBOL(sta2x11_get_instance); 128 129 130 /** 131 * p2a - Translate physical address to STA2x11 AMBA address, 132 * used for DMA transfers to STA2x11 133 * @p: Physical address 134 * @pdev: PCI device (must be hosted within the connext) 135 */ 136 static dma_addr_t p2a(dma_addr_t p, struct pci_dev *pdev) 137 { 138 struct sta2x11_mapping *map; 139 dma_addr_t a; 140 141 map = sta2x11_pdev_to_mapping(pdev); 142 a = p + map->amba_base; 143 return a; 144 } 145 146 /** 147 * a2p - Translate STA2x11 AMBA address to physical address 148 * used for DMA transfers from STA2x11 149 * @a: STA2x11 AMBA address 150 * @pdev: PCI device (must be hosted within the connext) 151 */ 152 static dma_addr_t a2p(dma_addr_t a, struct pci_dev *pdev) 153 { 154 struct sta2x11_mapping *map; 155 dma_addr_t p; 156 157 map = sta2x11_pdev_to_mapping(pdev); 158 p = a - map->amba_base; 159 return p; 160 } 161 162 /* At setup time, we use our own ops if the device is a ConneXt one */ 163 static void sta2x11_setup_pdev(struct pci_dev *pdev) 164 { 165 struct sta2x11_instance *instance = sta2x11_pdev_to_instance(pdev); 166 167 if (!instance) /* either a sta2x11 bridge or another ST device */ 168 return; 169 pci_set_consistent_dma_mask(pdev, STA2X11_AMBA_SIZE - 1); 170 pci_set_dma_mask(pdev, STA2X11_AMBA_SIZE - 1); 171 pdev->dev.dma_ops = &swiotlb_dma_ops; 172 pdev->dev.archdata.is_sta2x11 = true; 173 174 /* We must enable all devices as master, for audio DMA to work */ 175 pci_set_master(pdev); 176 } 177 DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_setup_pdev); 178 179 /* 180 * The following three functions are exported (used in swiotlb: FIXME) 181 */ 182 /** 183 * dma_capable - Check if device can manage DMA transfers (FIXME: kill it) 184 * @dev: device for a PCI device 185 * @addr: DMA address 186 * @size: DMA size 187 */ 188 bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) 189 { 190 struct sta2x11_mapping *map; 191 192 if (!dev->archdata.is_sta2x11) { 193 if (!dev->dma_mask) 194 return false; 195 return addr + size - 1 <= *dev->dma_mask; 196 } 197 198 map = sta2x11_pdev_to_mapping(to_pci_dev(dev)); 199 200 if (!map || (addr < map->amba_base)) 201 return false; 202 if (addr + size >= map->amba_base + STA2X11_AMBA_SIZE) { 203 return false; 204 } 205 206 return true; 207 } 208 209 /** 210 * __phys_to_dma - Return the DMA AMBA address used for this STA2x11 device 211 * @dev: device for a PCI device 212 * @paddr: Physical address 213 */ 214 dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr) 215 { 216 if (!dev->archdata.is_sta2x11) 217 return paddr; 218 return p2a(paddr, to_pci_dev(dev)); 219 } 220 221 /** 222 * dma_to_phys - Return the physical address used for this STA2x11 DMA address 223 * @dev: device for a PCI device 224 * @daddr: STA2x11 AMBA DMA address 225 */ 226 phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr) 227 { 228 if (!dev->archdata.is_sta2x11) 229 return daddr; 230 return a2p(daddr, to_pci_dev(dev)); 231 } 232 233 234 /* 235 * At boot we must set up the mappings for the pcie-to-amba bridge. 236 * It involves device access, and the same happens at suspend/resume time 237 */ 238 239 #define AHB_MAPB 0xCA4 240 #define AHB_CRW(i) (AHB_MAPB + 0 + (i) * 0x10) 241 #define AHB_CRW_SZMASK 0xfffffc00UL 242 #define AHB_CRW_ENABLE (1 << 0) 243 #define AHB_CRW_WTYPE_MEM (2 << 1) 244 #define AHB_CRW_ROE (1UL << 3) /* Relax Order Ena */ 245 #define AHB_CRW_NSE (1UL << 4) /* No Snoop Enable */ 246 #define AHB_BASE(i) (AHB_MAPB + 4 + (i) * 0x10) 247 #define AHB_PEXLBASE(i) (AHB_MAPB + 8 + (i) * 0x10) 248 #define AHB_PEXHBASE(i) (AHB_MAPB + 12 + (i) * 0x10) 249 250 /* At probe time, enable mapping for each endpoint, using the pdev */ 251 static void sta2x11_map_ep(struct pci_dev *pdev) 252 { 253 struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev); 254 int i; 255 256 if (!map) 257 return; 258 pci_read_config_dword(pdev, AHB_BASE(0), &map->amba_base); 259 260 /* Configure AHB mapping */ 261 pci_write_config_dword(pdev, AHB_PEXLBASE(0), 0); 262 pci_write_config_dword(pdev, AHB_PEXHBASE(0), 0); 263 pci_write_config_dword(pdev, AHB_CRW(0), STA2X11_AMBA_SIZE | 264 AHB_CRW_WTYPE_MEM | AHB_CRW_ENABLE); 265 266 /* Disable all the other windows */ 267 for (i = 1; i < STA2X11_NR_FUNCS; i++) 268 pci_write_config_dword(pdev, AHB_CRW(i), 0); 269 270 dev_info(&pdev->dev, 271 "sta2x11: Map EP %i: AMBA address %#8x-%#8x\n", 272 sta2x11_pdev_to_ep(pdev), map->amba_base, 273 map->amba_base + STA2X11_AMBA_SIZE - 1); 274 } 275 DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_map_ep); 276 277 #ifdef CONFIG_PM /* Some register values must be saved and restored */ 278 279 static void suspend_mapping(struct pci_dev *pdev) 280 { 281 struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev); 282 int i; 283 284 if (!map) 285 return; 286 287 if (map->is_suspended) 288 return; 289 map->is_suspended = 1; 290 291 /* Save all window configs */ 292 for (i = 0; i < STA2X11_NR_FUNCS; i++) { 293 struct sta2x11_ahb_regs *regs = map->regs + i; 294 295 pci_read_config_dword(pdev, AHB_BASE(i), ®s->base); 296 pci_read_config_dword(pdev, AHB_PEXLBASE(i), ®s->pexlbase); 297 pci_read_config_dword(pdev, AHB_PEXHBASE(i), ®s->pexhbase); 298 pci_read_config_dword(pdev, AHB_CRW(i), ®s->crw); 299 } 300 } 301 DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, suspend_mapping); 302 303 static void resume_mapping(struct pci_dev *pdev) 304 { 305 struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev); 306 int i; 307 308 if (!map) 309 return; 310 311 312 if (!map->is_suspended) 313 goto out; 314 map->is_suspended = 0; 315 316 /* Restore all window configs */ 317 for (i = 0; i < STA2X11_NR_FUNCS; i++) { 318 struct sta2x11_ahb_regs *regs = map->regs + i; 319 320 pci_write_config_dword(pdev, AHB_BASE(i), regs->base); 321 pci_write_config_dword(pdev, AHB_PEXLBASE(i), regs->pexlbase); 322 pci_write_config_dword(pdev, AHB_PEXHBASE(i), regs->pexhbase); 323 pci_write_config_dword(pdev, AHB_CRW(i), regs->crw); 324 } 325 out: 326 pci_set_master(pdev); /* Like at boot, enable master on all devices */ 327 } 328 DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, resume_mapping); 329 330 #endif /* CONFIG_PM */ 331