arch/ia64/sn/pci/pcibr/pcibr_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) 2001-2004 Silicon Graphics, Inc. All rights reserved.
   7  */
   8
   9 #include <linux/types.h>
  10 #include <linux/pci.h>
  11 #include <asm/sn/sn_sal.h>
  12 #include <asm/sn/geo.h>
  13 #include "xtalk/xwidgetdev.h"
  14 #include "xtalk/hubdev.h"
  15 #include "pci/pcibus_provider_defs.h"
  16 #include "pci/pcidev.h"
  17 #include "pci/tiocp.h"
  18 #include "pci/pic.h"
  19 #include "pci/pcibr_provider.h"
  20 #include "pci/tiocp.h"
  21 #include "tio.h"
  22 #include <asm/sn/addrs.h>
  23
  24 extern int sn_ioif_inited;
  25
  26 /* =====================================================================
  27  *    DMA MANAGEMENT
  28  *
  29  *      The Bridge ASIC provides three methods of doing DMA: via a "direct map"
  30  *      register available in 32-bit PCI space (which selects a contiguous 2G
  31  *      address space on some other widget), via "direct" addressing via 64-bit
  32  *      PCI space (all destination information comes from the PCI address,
  33  *      including transfer attributes), and via a "mapped" region that allows
  34  *      a bunch of different small mappings to be established with the PMU.
  35  *
  36  *      For efficiency, we most prefer to use the 32bit direct mapping facility,
  37  *      since it requires no resource allocations. The advantage of using the
  38  *      PMU over the 64-bit direct is that single-cycle PCI addressing can be
  39  *      used; the advantage of using 64-bit direct over PMU addressing is that
  40  *      we do not have to allocate entries in the PMU.
  41  */
  42
  43 static uint64_t
  44 pcibr_dmamap_ate32(struct pcidev_info *info,
  45                    uint64_t paddr, size_t req_size, uint64_t flags)
  46 {
  47
  48         struct pcidev_info *pcidev_info = info->pdi_host_pcidev_info;
  49         struct pcibus_info *pcibus_info = (struct pcibus_info *)pcidev_info->
  50             pdi_pcibus_info;
  51         uint8_t internal_device = (PCI_SLOT(pcidev_info->pdi_host_pcidev_info->
  52                                             pdi_linux_pcidev->devfn)) - 1;
  53         int ate_count;
  54         int ate_index;
  55         uint64_t ate_flags = flags | PCI32_ATE_V;
  56         uint64_t ate;
  57         uint64_t pci_addr;
  58         uint64_t xio_addr;
  59         uint64_t offset;
  60
  61         /* PIC in PCI-X mode does not supports 32bit PageMap mode */
  62         if (IS_PIC_SOFT(pcibus_info) && IS_PCIX(pcibus_info)) {
  63                 return 0;
  64         }
  65
  66         /* Calculate the number of ATEs needed. */
  67         if (!(MINIMAL_ATE_FLAG(paddr, req_size))) {
  68                 ate_count = IOPG((IOPGSIZE - 1) /* worst case start offset */
  69                                  +req_size      /* max mapping bytes */
  70                                  - 1) + 1;      /* round UP */
  71         } else {                /* assume requested target is page aligned */
  72                 ate_count = IOPG(req_size       /* max mapping bytes */
  73                                  - 1) + 1;      /* round UP */
  74         }
  75
  76         /* Get the number of ATEs required. */
  77         ate_index = pcibr_ate_alloc(pcibus_info, ate_count);
  78         if (ate_index < 0)
  79                 return 0;
  80
  81         /* In PCI-X mode, Prefetch not supported */
  82         if (IS_PCIX(pcibus_info))
  83                 ate_flags &= ~(PCI32_ATE_PREF);
  84
  85         xio_addr =
  86             IS_PIC_SOFT(pcibus_info) ? PHYS_TO_DMA(paddr) :
  87             PHYS_TO_TIODMA(paddr);
  88         offset = IOPGOFF(xio_addr);
  89         ate = ate_flags | (xio_addr - offset);
  90
  91         /* If PIC, put the targetid in the ATE */
  92         if (IS_PIC_SOFT(pcibus_info)) {
  93                 ate |= (pcibus_info->pbi_hub_xid << PIC_ATE_TARGETID_SHFT);
  94         }
  95         ate_write(pcibus_info, ate_index, ate_count, ate);
  96
  97         /*
  98          * Set up the DMA mapped Address.
  99          */
 100         pci_addr = PCI32_MAPPED_BASE + offset + IOPGSIZE * ate_index;
 101
 102         /*
 103          * If swap was set in device in pcibr_endian_set()
 104          * we need to turn swapping on.
 105          */
 106         if (pcibus_info->pbi_devreg[internal_device] & PCIBR_DEV_SWAP_DIR)
 107                 ATE_SWAP_ON(pci_addr);
 108
 109         return pci_addr;
 110 }
 111
 112 static uint64_t
 113 pcibr_dmatrans_direct64(struct pcidev_info * info, uint64_t paddr,
 114                         uint64_t dma_attributes)
 115 {
 116         struct pcibus_info *pcibus_info = (struct pcibus_info *)
 117             ((info->pdi_host_pcidev_info)->pdi_pcibus_info);
 118         uint64_t pci_addr;
 119
 120         /* Translate to Crosstalk View of Physical Address */
 121         pci_addr = (IS_PIC_SOFT(pcibus_info) ? PHYS_TO_DMA(paddr) :
 122                     PHYS_TO_TIODMA(paddr)) | dma_attributes;
 123
 124         /* Handle Bus mode */
 125         if (IS_PCIX(pcibus_info))
 126                 pci_addr &= ~PCI64_ATTR_PREF;
 127
 128         /* Handle Bridge Chipset differences */
 129         if (IS_PIC_SOFT(pcibus_info)) {
 130                 pci_addr |=
 131                     ((uint64_t) pcibus_info->
 132                      pbi_hub_xid << PIC_PCI64_ATTR_TARG_SHFT);
 133         } else
 134                 pci_addr |= TIOCP_PCI64_CMDTYPE_MEM;
 135
 136         /* If PCI mode, func zero uses VCHAN0, every other func uses VCHAN1 */
 137         if (!IS_PCIX(pcibus_info) && PCI_FUNC(info->pdi_linux_pcidev->devfn))
 138                 pci_addr |= PCI64_ATTR_VIRTUAL;
 139
 140         return pci_addr;
 141
 142 }
 143
 144 static uint64_t
 145 pcibr_dmatrans_direct32(struct pcidev_info * info,
 146                         uint64_t paddr, size_t req_size, uint64_t flags)
 147 {
 148
 149         struct pcidev_info *pcidev_info = info->pdi_host_pcidev_info;
 150         struct pcibus_info *pcibus_info = (struct pcibus_info *)pcidev_info->
 151             pdi_pcibus_info;
 152         uint64_t xio_addr;
 153
 154         uint64_t xio_base;
 155         uint64_t offset;
 156         uint64_t endoff;
 157
 158         if (IS_PCIX(pcibus_info)) {
 159                 return 0;
 160         }
 161
 162         xio_addr = IS_PIC_SOFT(pcibus_info) ? PHYS_TO_DMA(paddr) :
 163             PHYS_TO_TIODMA(paddr);
 164
 165         xio_base = pcibus_info->pbi_dir_xbase;
 166         offset = xio_addr - xio_base;
 167         endoff = req_size + offset;
 168         if ((req_size > (1ULL << 31)) ||        /* Too Big */
 169             (xio_addr < xio_base) ||    /* Out of range for mappings */
 170             (endoff > (1ULL << 31))) {  /* Too Big */
 171                 return 0;
 172         }
 173
 174         return PCI32_DIRECT_BASE | offset;
 175
 176 }
 177
 178 /*
 179  * Wrapper routine for free'ing DMA maps
 180  * DMA mappings for Direct 64 and 32 do not have any DMA maps.
 181  */
 182 void
 183 pcibr_dma_unmap(struct pcidev_info *pcidev_info, dma_addr_t dma_handle,
 184                 int direction)
 185 {
 186         struct pcibus_info *pcibus_info = (struct pcibus_info *)pcidev_info->
 187             pdi_pcibus_info;
 188
 189         if (IS_PCI32_MAPPED(dma_handle)) {
 190                 int ate_index;
 191
 192                 ate_index =
 193                     IOPG((ATE_SWAP_OFF(dma_handle) - PCI32_MAPPED_BASE));
 194                 pcibr_ate_free(pcibus_info, ate_index);
 195         }
 196 }
 197
 198 /*
 199  * On SN systems there is a race condition between a PIO read response and
 200  * DMA's.  In rare cases, the read response may beat the DMA, causing the
 201  * driver to think that data in memory is complete and meaningful.  This code
 202  * eliminates that race.  This routine is called by the PIO read routines
 203  * after doing the read.  For PIC this routine then forces a fake interrupt
 204  * on another line, which is logically associated with the slot that the PIO
 205  * is addressed to.  It then spins while watching the memory location that
 206  * the interrupt is targetted to.  When the interrupt response arrives, we
 207  * are sure that the DMA has landed in memory and it is safe for the driver
 208  * to proceed.  For TIOCP use the Device(x) Write Request Buffer Flush
 209  * Bridge register since it ensures the data has entered the coherence domain,
 210  * unlike the PIC Device(x) Write Request Buffer Flush register.
 211  */
 212
 213 void sn_dma_flush(uint64_t addr)
 214 {
 215         nasid_t nasid;
 216         int is_tio;
 217         int wid_num;
 218         int i, j;
 219         int bwin;
 220         uint64_t flags;
 221         struct hubdev_info *hubinfo;
 222         volatile struct sn_flush_device_list *p;
 223         struct sn_flush_nasid_entry *flush_nasid_list;
 224
 225         if (!sn_ioif_inited)
 226                 return;
 227
 228         nasid = NASID_GET(addr);
 229         if (-1 == nasid_to_cnodeid(nasid))
 230                 return;
 231
 232         hubinfo = (NODEPDA(nasid_to_cnodeid(nasid)))->pdinfo;
 233
 234         if (!hubinfo) {
 235                 BUG();
 236         }
 237         is_tio = (nasid & 1);
 238         if (is_tio) {
 239                 wid_num = TIO_SWIN_WIDGETNUM(addr);
 240                 bwin = TIO_BWIN_WINDOWNUM(addr);
 241         } else {
 242                 wid_num = SWIN_WIDGETNUM(addr);
 243                 bwin = BWIN_WINDOWNUM(addr);
 244         }
 245
 246         flush_nasid_list = &hubinfo->hdi_flush_nasid_list;
 247         if (flush_nasid_list->widget_p == NULL)
 248                 return;
 249         if (bwin > 0) {
 250                 uint64_t itte = flush_nasid_list->iio_itte[bwin];
 251
 252                 if (is_tio) {
 253                         wid_num = (itte >> TIO_ITTE_WIDGET_SHIFT) &
 254                             TIO_ITTE_WIDGET_MASK;
 255                 } else {
 256                         wid_num = (itte >> IIO_ITTE_WIDGET_SHIFT) &
 257                             IIO_ITTE_WIDGET_MASK;
 258                 }
 259         }
 260         if (flush_nasid_list->widget_p == NULL)
 261                 return;
 262         if (flush_nasid_list->widget_p[wid_num] == NULL)
 263                 return;
 264         p = &flush_nasid_list->widget_p[wid_num][0];
 265
 266         /* find a matching BAR */
 267         for (i = 0; i < DEV_PER_WIDGET; i++) {
 268                 for (j = 0; j < PCI_ROM_RESOURCE; j++) {
 269                         if (p->sfdl_bar_list[j].start == 0)
 270                                 break;
 271                         if (addr >= p->sfdl_bar_list[j].start
 272                             && addr <= p->sfdl_bar_list[j].end)
 273                                 break;
 274                 }
 275                 if (j < PCI_ROM_RESOURCE && p->sfdl_bar_list[j].start != 0)
 276                         break;
 277                 p++;
 278         }
 279
 280         /* if no matching BAR, return without doing anything. */
 281         if (i == DEV_PER_WIDGET)
 282                 return;
 283
 284         /*
 285          * For TIOCP use the Device(x) Write Request Buffer Flush Bridge
 286          * register since it ensures the data has entered the coherence
 287          * domain, unlike PIC
 288          */
 289         if (is_tio) {
 290                 uint32_t tio_id = REMOTE_HUB_L(nasid, TIO_NODE_ID);
 291                 uint32_t revnum = XWIDGET_PART_REV_NUM(tio_id);
 292
 293                 /* TIOCP BRINGUP WAR (PV907516): Don't write buffer flush reg */
 294                 if ((1 << XWIDGET_PART_REV_NUM_REV(revnum)) & PV907516) {
 295                         return;
 296                 } else {
 297                         pcireg_wrb_flush_get(p->sfdl_pcibus_info,
 298                                              (p->sfdl_slot - 1));
 299                 }
 300         } else {
 301                 spin_lock_irqsave(&((struct sn_flush_device_list *)p)->
 302                                   sfdl_flush_lock, flags);
 303
 304                 p->sfdl_flush_value = 0;
 305
 306                 /* force an interrupt. */
 307                 *(volatile uint32_t *)(p->sfdl_force_int_addr) = 1;
 308
 309                 /* wait for the interrupt to come back. */
 310                 while (*(p->sfdl_flush_addr) != 0x10f) ;
 311
 312                 /* okay, everything is synched up. */
 313                 spin_unlock_irqrestore((spinlock_t *)&p->sfdl_flush_lock, flags);
 314         }
 315         return;
 316 }
 317
 318 /*
 319  * Wrapper DMA interface.  Called from pci_dma.c routines.
 320  */
 321
 322 uint64_t
 323 pcibr_dma_map(struct pcidev_info * pcidev_info, unsigned long phys_addr,
 324               size_t size, unsigned int flags)
 325 {
 326         dma_addr_t dma_handle;
 327         struct pci_dev *pcidev = pcidev_info->pdi_linux_pcidev;
 328
 329         if (flags & SN_PCIDMA_CONSISTENT) {
 330                 /* sn_pci_alloc_consistent interfaces */
 331                 if (pcidev->dev.coherent_dma_mask == ~0UL) {
 332                         dma_handle =
 333                             pcibr_dmatrans_direct64(pcidev_info, phys_addr,
 334                                                     PCI64_ATTR_BAR);
 335                 } else {
 336                         dma_handle =
 337                             (dma_addr_t) pcibr_dmamap_ate32(pcidev_info,
 338                                                             phys_addr, size,
 339                                                             PCI32_ATE_BAR);
 340                 }
 341         } else {
 342                 /* map_sg/map_single interfaces */
 343
 344                 /* SN cannot support DMA addresses smaller than 32 bits. */
 345                 if (pcidev->dma_mask < 0x7fffffff) {
 346                         return 0;
 347                 }
 348
 349                 if (pcidev->dma_mask == ~0UL) {
 350                         /*
 351                          * Handle the most common case: 64 bit cards.  This
 352                          * call should always succeed.
 353                          */
 354
 355                         dma_handle =
 356                             pcibr_dmatrans_direct64(pcidev_info, phys_addr,
 357                                                     PCI64_ATTR_PREF);
 358                 } else {
 359                         /* Handle 32-63 bit cards via direct mapping */
 360                         dma_handle =
 361                             pcibr_dmatrans_direct32(pcidev_info, phys_addr,
 362                                                     size, 0);
 363                         if (!dma_handle) {
 364                                 /*
 365                                  * It is a 32 bit card and we cannot do direct mapping,
 366                                  * so we use an ATE.
 367                                  */
 368
 369                                 dma_handle =
 370                                     pcibr_dmamap_ate32(pcidev_info, phys_addr,
 371                                                        size, PCI32_ATE_PREF);
 372                         }
 373                 }
 374         }
 375
 376         return dma_handle;
 377 }
 378
 379 EXPORT_SYMBOL(sn_dma_flush);