arch/ia64/sn/pci/pci_dma.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2000,2002-2005 Silicon Graphics, Inc. All rights reserved.
   7  *
   8  * Routines for PCI DMA mapping.  See Documentation/DMA-API.txt for
   9  * a description of how these routines should be used.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <asm/dma.h>
  14 #include <asm/sn/intr.h>
  15 #include <asm/sn/pcibus_provider_defs.h>
  16 #include <asm/sn/pcidev.h>
  17 #include <asm/sn/sn_sal.h>
  18
  19 #define SG_ENT_VIRT_ADDRESS(sg) (page_address((sg)->page) + (sg)->offset)
  20 #define SG_ENT_PHYS_ADDRESS(SG) virt_to_phys(SG_ENT_VIRT_ADDRESS(SG))
  21
  22 /**
  23  * sn_dma_supported - test a DMA mask
  24  * @dev: device to test
  25  * @mask: DMA mask to test
  26  *
  27  * Return whether the given PCI device DMA address mask can be supported
  28  * properly.  For example, if your device can only drive the low 24-bits
  29  * during PCI bus mastering, then you would pass 0x00ffffff as the mask to
  30  * this function.  Of course, SN only supports devices that have 32 or more
  31  * address bits when using the PMU.
  32  */
  33 int sn_dma_supported(struct device *dev, u64 mask)
  34 {
  35         BUG_ON(dev->bus != &pci_bus_type);
  36
  37         if (mask < 0x7fffffff)
  38                 return 0;
  39         return 1;
  40 }
  41 EXPORT_SYMBOL(sn_dma_supported);
  42
  43 /**
  44  * sn_dma_set_mask - set the DMA mask
  45  * @dev: device to set
  46  * @dma_mask: new mask
  47  *
  48  * Set @dev's DMA mask if the hw supports it.
  49  */
  50 int sn_dma_set_mask(struct device *dev, u64 dma_mask)
  51 {
  52         BUG_ON(dev->bus != &pci_bus_type);
  53
  54         if (!sn_dma_supported(dev, dma_mask))
  55                 return 0;
  56
  57         *dev->dma_mask = dma_mask;
  58         return 1;
  59 }
  60 EXPORT_SYMBOL(sn_dma_set_mask);
  61
  62 /**
  63  * sn_dma_alloc_coherent - allocate memory for coherent DMA
  64  * @dev: device to allocate for
  65  * @size: size of the region
  66  * @dma_handle: DMA (bus) address
  67  * @flags: memory allocation flags
  68  *
  69  * dma_alloc_coherent() returns a pointer to a memory region suitable for
  70  * coherent DMA traffic to/from a PCI device.  On SN platforms, this means
  71  * that @dma_handle will have the %PCIIO_DMA_CMD flag set.
  72  *
  73  * This interface is usually used for "command" streams (e.g. the command
  74  * queue for a SCSI controller).  See Documentation/DMA-API.txt for
  75  * more information.
  76  */
  77 void *sn_dma_alloc_coherent(struct device *dev, size_t size,
  78                             dma_addr_t * dma_handle, gfp_t flags)
  79 {
  80         void *cpuaddr;
  81         unsigned long phys_addr;
  82         int node;
  83         struct pci_dev *pdev = to_pci_dev(dev);
  84         struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
  85
  86         BUG_ON(dev->bus != &pci_bus_type);
  87
  88         /*
  89          * Allocate the memory.
  90          */
  91         node = pcibus_to_node(pdev->bus);
  92         if (likely(node >=0)) {
  93                 struct page *p = alloc_pages_node(node, flags, get_order(size));
  94
  95                 if (likely(p))
  96                         cpuaddr = page_address(p);
  97                 else
  98                         return NULL;
  99         } else
 100                 cpuaddr = (void *)__get_free_pages(flags, get_order(size));
 101
 102         if (unlikely(!cpuaddr))
 103                 return NULL;
 104
 105         memset(cpuaddr, 0x0, size);
 106
 107         /* physical addr. of the memory we just got */
 108         phys_addr = __pa(cpuaddr);
 109
 110         /*
 111          * 64 bit address translations should never fail.
 112          * 32 bit translations can fail if there are insufficient mapping
 113          * resources.
 114          */
 115
 116         *dma_handle = provider->dma_map_consistent(pdev, phys_addr, size,
 117                                                    SN_DMA_ADDR_PHYS);
 118         if (!*dma_handle) {
 119                 printk(KERN_ERR "%s: out of ATEs\n", __FUNCTION__);
 120                 free_pages((unsigned long)cpuaddr, get_order(size));
 121                 return NULL;
 122         }
 123
 124         return cpuaddr;
 125 }
 126 EXPORT_SYMBOL(sn_dma_alloc_coherent);
 127
 128 /**
 129  * sn_pci_free_coherent - free memory associated with coherent DMAable region
 130  * @dev: device to free for
 131  * @size: size to free
 132  * @cpu_addr: kernel virtual address to free
 133  * @dma_handle: DMA address associated with this region
 134  *
 135  * Frees the memory allocated by dma_alloc_coherent(), potentially unmapping
 136  * any associated IOMMU mappings.
 137  */
 138 void sn_dma_free_coherent(struct device *dev, size_t size, void *cpu_addr,
 139                           dma_addr_t dma_handle)
 140 {
 141         struct pci_dev *pdev = to_pci_dev(dev);
 142         struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
 143
 144         BUG_ON(dev->bus != &pci_bus_type);
 145
 146         provider->dma_unmap(pdev, dma_handle, 0);
 147         free_pages((unsigned long)cpu_addr, get_order(size));
 148 }
 149 EXPORT_SYMBOL(sn_dma_free_coherent);
 150
 151 /**
 152  * sn_dma_map_single - map a single page for DMA
 153  * @dev: device to map for
 154  * @cpu_addr: kernel virtual address of the region to map
 155  * @size: size of the region
 156  * @direction: DMA direction
 157  *
 158  * Map the region pointed to by @cpu_addr for DMA and return the
 159  * DMA address.
 160  *
 161  * We map this to the one step pcibr_dmamap_trans interface rather than
 162  * the two step pcibr_dmamap_alloc/pcibr_dmamap_addr because we have
 163  * no way of saving the dmamap handle from the alloc to later free
 164  * (which is pretty much unacceptable).
 165  *
 166  * TODO: simplify our interface;
 167  *       figure out how to save dmamap handle so can use two step.
 168  */
 169 dma_addr_t sn_dma_map_single(struct device *dev, void *cpu_addr, size_t size,
 170                              int direction)
 171 {
 172         dma_addr_t dma_addr;
 173         unsigned long phys_addr;
 174         struct pci_dev *pdev = to_pci_dev(dev);
 175         struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
 176
 177         BUG_ON(dev->bus != &pci_bus_type);
 178
 179         phys_addr = __pa(cpu_addr);
 180         dma_addr = provider->dma_map(pdev, phys_addr, size, SN_DMA_ADDR_PHYS);
 181         if (!dma_addr) {
 182                 printk(KERN_ERR "%s: out of ATEs\n", __FUNCTION__);
 183                 return 0;
 184         }
 185         return dma_addr;
 186 }
 187 EXPORT_SYMBOL(sn_dma_map_single);
 188
 189 /**
 190  * sn_dma_unmap_single - unamp a DMA mapped page
 191  * @dev: device to sync
 192  * @dma_addr: DMA address to sync
 193  * @size: size of region
 194  * @direction: DMA direction
 195  *
 196  * This routine is supposed to sync the DMA region specified
 197  * by @dma_handle into the coherence domain.  On SN, we're always cache
 198  * coherent, so we just need to free any ATEs associated with this mapping.
 199  */
 200 void sn_dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
 201                          int direction)
 202 {
 203         struct pci_dev *pdev = to_pci_dev(dev);
 204         struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
 205
 206         BUG_ON(dev->bus != &pci_bus_type);
 207
 208         provider->dma_unmap(pdev, dma_addr, direction);
 209 }
 210 EXPORT_SYMBOL(sn_dma_unmap_single);
 211
 212 /**
 213  * sn_dma_unmap_sg - unmap a DMA scatterlist
 214  * @dev: device to unmap
 215  * @sg: scatterlist to unmap
 216  * @nhwentries: number of scatterlist entries
 217  * @direction: DMA direction
 218  *
 219  * Unmap a set of streaming mode DMA translations.
 220  */
 221 void sn_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 222                      int nhwentries, int direction)
 223 {
 224         int i;
 225         struct pci_dev *pdev = to_pci_dev(dev);
 226         struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
 227
 228         BUG_ON(dev->bus != &pci_bus_type);
 229
 230         for (i = 0; i < nhwentries; i++, sg++) {
 231                 provider->dma_unmap(pdev, sg->dma_address, direction);
 232                 sg->dma_address = (dma_addr_t) NULL;
 233                 sg->dma_length = 0;
 234         }
 235 }
 236 EXPORT_SYMBOL(sn_dma_unmap_sg);
 237
 238 /**
 239  * sn_dma_map_sg - map a scatterlist for DMA
 240  * @dev: device to map for
 241  * @sg: scatterlist to map
 242  * @nhwentries: number of entries
 243  * @direction: direction of the DMA transaction
 244  *
 245  * Maps each entry of @sg for DMA.
 246  */
 247 int sn_dma_map_sg(struct device *dev, struct scatterlist *sg, int nhwentries,
 248                   int direction)
 249 {
 250         unsigned long phys_addr;
 251         struct scatterlist *saved_sg = sg;
 252         struct pci_dev *pdev = to_pci_dev(dev);
 253         struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
 254         int i;
 255
 256         BUG_ON(dev->bus != &pci_bus_type);
 257
 258         /*
 259          * Setup a DMA address for each entry in the scatterlist.
 260          */
 261         for (i = 0; i < nhwentries; i++, sg++) {
 262                 phys_addr = SG_ENT_PHYS_ADDRESS(sg);
 263                 sg->dma_address = provider->dma_map(pdev,
 264                                                     phys_addr, sg->length,
 265                                                     SN_DMA_ADDR_PHYS);
 266
 267                 if (!sg->dma_address) {
 268                         printk(KERN_ERR "%s: out of ATEs\n", __FUNCTION__);
 269
 270                         /*
 271                          * Free any successfully allocated entries.
 272                          */
 273                         if (i > 0)
 274                                 sn_dma_unmap_sg(dev, saved_sg, i, direction);
 275                         return 0;
 276                 }
 277
 278                 sg->dma_length = sg->length;
 279         }
 280
 281         return nhwentries;
 282 }
 283 EXPORT_SYMBOL(sn_dma_map_sg);
 284
 285 void sn_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
 286                                 size_t size, int direction)
 287 {
 288         BUG_ON(dev->bus != &pci_bus_type);
 289 }
 290 EXPORT_SYMBOL(sn_dma_sync_single_for_cpu);
 291
 292 void sn_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle,
 293                                    size_t size, int direction)
 294 {
 295         BUG_ON(dev->bus != &pci_bus_type);
 296 }
 297 EXPORT_SYMBOL(sn_dma_sync_single_for_device);
 298
 299 void sn_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
 300                             int nelems, int direction)
 301 {
 302         BUG_ON(dev->bus != &pci_bus_type);
 303 }
 304 EXPORT_SYMBOL(sn_dma_sync_sg_for_cpu);
 305
 306 void sn_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
 307                                int nelems, int direction)
 308 {
 309         BUG_ON(dev->bus != &pci_bus_type);
 310 }
 311 EXPORT_SYMBOL(sn_dma_sync_sg_for_device);
 312
 313 int sn_dma_mapping_error(dma_addr_t dma_addr)
 314 {
 315         return 0;
 316 }
 317 EXPORT_SYMBOL(sn_dma_mapping_error);
 318
 319 char *sn_pci_get_legacy_mem(struct pci_bus *bus)
 320 {
 321         if (!SN_PCIBUS_BUSSOFT(bus))
 322                 return ERR_PTR(-ENODEV);
 323
 324         return (char *)(SN_PCIBUS_BUSSOFT(bus)->bs_legacy_mem | __IA64_UNCACHED_OFFSET);
 325 }
 326
 327 int sn_pci_legacy_read(struct pci_bus *bus, u16 port, u32 *val, u8 size)
 328 {
 329         unsigned long addr;
 330         int ret;
 331         struct ia64_sal_retval isrv;
 332
 333         /*
 334          * First, try the SN_SAL_IOIF_PCI_SAFE SAL call which can work
 335          * around hw issues at the pci bus level.  SGI proms older than
 336          * 4.10 don't implement this.
 337          */
 338
 339         SAL_CALL(isrv, SN_SAL_IOIF_PCI_SAFE,
 340                  pci_domain_nr(bus), bus->number,
 341                  0, /* io */
 342                  0, /* read */
 343                  port, size, __pa(val));
 344
 345         if (isrv.status == 0)
 346                 return size;
 347
 348         /*
 349          * If the above failed, retry using the SAL_PROBE call which should
 350          * be present in all proms (but which cannot work round PCI chipset
 351          * bugs).  This code is retained for compatibility with old
 352          * pre-4.10 proms, and should be removed at some point in the future.
 353          */
 354
 355         if (!SN_PCIBUS_BUSSOFT(bus))
 356                 return -ENODEV;
 357
 358         addr = SN_PCIBUS_BUSSOFT(bus)->bs_legacy_io | __IA64_UNCACHED_OFFSET;
 359         addr += port;
 360
 361         ret = ia64_sn_probe_mem(addr, (long)size, (void *)val);
 362
 363         if (ret == 2)
 364                 return -EINVAL;
 365
 366         if (ret == 1)
 367                 *val = -1;
 368
 369         return size;
 370 }
 371
 372 int sn_pci_legacy_write(struct pci_bus *bus, u16 port, u32 val, u8 size)
 373 {
 374         int ret = size;
 375         unsigned long paddr;
 376         unsigned long *addr;
 377         struct ia64_sal_retval isrv;
 378
 379         /*
 380          * First, try the SN_SAL_IOIF_PCI_SAFE SAL call which can work
 381          * around hw issues at the pci bus level.  SGI proms older than
 382          * 4.10 don't implement this.
 383          */
 384
 385         SAL_CALL(isrv, SN_SAL_IOIF_PCI_SAFE,
 386                  pci_domain_nr(bus), bus->number,
 387                  0, /* io */
 388                  1, /* write */
 389                  port, size, __pa(&val));
 390
 391         if (isrv.status == 0)
 392                 return size;
 393
 394         /*
 395          * If the above failed, retry using the SAL_PROBE call which should
 396          * be present in all proms (but which cannot work round PCI chipset
 397          * bugs).  This code is retained for compatibility with old
 398          * pre-4.10 proms, and should be removed at some point in the future.
 399          */
 400
 401         if (!SN_PCIBUS_BUSSOFT(bus)) {
 402                 ret = -ENODEV;
 403                 goto out;
 404         }
 405
 406         /* Put the phys addr in uncached space */
 407         paddr = SN_PCIBUS_BUSSOFT(bus)->bs_legacy_io | __IA64_UNCACHED_OFFSET;
 408         paddr += port;
 409         addr = (unsigned long *)paddr;
 410
 411         switch (size) {
 412         case 1:
 413                 *(volatile u8 *)(addr) = (u8)(val);
 414                 break;
 415         case 2:
 416                 *(volatile u16 *)(addr) = (u16)(val);
 417                 break;
 418         case 4:
 419                 *(volatile u32 *)(addr) = (u32)(val);
 420                 break;
 421         default:
 422                 ret = -EINVAL;
 423                 break;
 424         }
 425  out:
 426         return ret;
 427 }