arch/s390/pci/pci_clp.c

   1 /*
   2  * Copyright IBM Corp. 2012
   3  *
   4  * Author(s):
   5  *   Jan Glauber <[email protected]>
   6  */
   7
   8 #define COMPONENT "zPCI"
   9 #define pr_fmt(fmt) COMPONENT ": " fmt
  10
  11 #include <linux/kernel.h>
  12 #include <linux/slab.h>
  13 #include <linux/err.h>
  14 #include <linux/delay.h>
  15 #include <linux/pci.h>
  16 #include <asm/pci_clp.h>
  17
  18 /*
  19  * Call Logical Processor
  20  * Retry logic is handled by the caller.
  21  */
  22 static inline u8 clp_instr(void *data)
  23 {
  24         struct { u8 _[CLP_BLK_SIZE]; } *req = data;
  25         u64 ignored;
  26         u8 cc;
  27
  28         asm volatile (
  29                 "       .insn   rrf,0xb9a00000,%[ign],%[req],0x0,0x2\n"
  30                 "       ipm     %[cc]\n"
  31                 "       srl     %[cc],28\n"
  32                 : [cc] "=d" (cc), [ign] "=d" (ignored), "+m" (*req)
  33                 : [req] "a" (req)
  34                 : "cc");
  35         return cc;
  36 }
  37
  38 static void *clp_alloc_block(void)
  39 {
  40         return (void *) __get_free_pages(GFP_KERNEL, get_order(CLP_BLK_SIZE));
  41 }
  42
  43 static void clp_free_block(void *ptr)
  44 {
  45         free_pages((unsigned long) ptr, get_order(CLP_BLK_SIZE));
  46 }
  47
  48 static void clp_store_query_pci_fngrp(struct zpci_dev *zdev,
  49                                       struct clp_rsp_query_pci_grp *response)
  50 {
  51         zdev->tlb_refresh = response->refresh;
  52         zdev->dma_mask = response->dasm;
  53         zdev->msi_addr = response->msia;
  54         zdev->fmb_update = response->mui;
  55
  56         pr_debug("Supported number of MSI vectors: %u\n", response->noi);
  57         switch (response->version) {
  58         case 1:
  59                 zdev->max_bus_speed = PCIE_SPEED_5_0GT;
  60                 break;
  61         default:
  62                 zdev->max_bus_speed = PCI_SPEED_UNKNOWN;
  63                 break;
  64         }
  65 }
  66
  67 static int clp_query_pci_fngrp(struct zpci_dev *zdev, u8 pfgid)
  68 {
  69         struct clp_req_rsp_query_pci_grp *rrb;
  70         int rc;
  71
  72         rrb = clp_alloc_block();
  73         if (!rrb)
  74                 return -ENOMEM;
  75
  76         memset(rrb, 0, sizeof(*rrb));
  77         rrb->request.hdr.len = sizeof(rrb->request);
  78         rrb->request.hdr.cmd = CLP_QUERY_PCI_FNGRP;
  79         rrb->response.hdr.len = sizeof(rrb->response);
  80         rrb->request.pfgid = pfgid;
  81
  82         rc = clp_instr(rrb);
  83         if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
  84                 clp_store_query_pci_fngrp(zdev, &rrb->response);
  85         else {
  86                 pr_err("Query PCI FNGRP failed with response: %x  cc: %d\n",
  87                         rrb->response.hdr.rsp, rc);
  88                 rc = -EIO;
  89         }
  90         clp_free_block(rrb);
  91         return rc;
  92 }
  93
  94 static int clp_store_query_pci_fn(struct zpci_dev *zdev,
  95                                   struct clp_rsp_query_pci *response)
  96 {
  97         int i;
  98
  99         for (i = 0; i < PCI_BAR_COUNT; i++) {
 100                 zdev->bars[i].val = le32_to_cpu(response->bar[i]);
 101                 zdev->bars[i].size = response->bar_size[i];
 102         }
 103         zdev->start_dma = response->sdma;
 104         zdev->end_dma = response->edma;
 105         zdev->pchid = response->pchid;
 106         zdev->pfgid = response->pfgid;
 107         return 0;
 108 }
 109
 110 static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh)
 111 {
 112         struct clp_req_rsp_query_pci *rrb;
 113         int rc;
 114
 115         rrb = clp_alloc_block();
 116         if (!rrb)
 117                 return -ENOMEM;
 118
 119         memset(rrb, 0, sizeof(*rrb));
 120         rrb->request.hdr.len = sizeof(rrb->request);
 121         rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;
 122         rrb->response.hdr.len = sizeof(rrb->response);
 123         rrb->request.fh = fh;
 124
 125         rc = clp_instr(rrb);
 126         if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
 127                 rc = clp_store_query_pci_fn(zdev, &rrb->response);
 128                 if (rc)
 129                         goto out;
 130                 if (rrb->response.pfgid)
 131                         rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
 132         } else {
 133                 pr_err("Query PCI failed with response: %x  cc: %d\n",
 134                          rrb->response.hdr.rsp, rc);
 135                 rc = -EIO;
 136         }
 137 out:
 138         clp_free_block(rrb);
 139         return rc;
 140 }
 141
 142 int clp_add_pci_device(u32 fid, u32 fh, int configured)
 143 {
 144         struct zpci_dev *zdev;
 145         int rc;
 146
 147         zdev = zpci_alloc_device();
 148         if (IS_ERR(zdev))
 149                 return PTR_ERR(zdev);
 150
 151         zdev->fh = fh;
 152         zdev->fid = fid;
 153
 154         /* Query function properties and update zdev */
 155         rc = clp_query_pci_fn(zdev, fh);
 156         if (rc)
 157                 goto error;
 158
 159         if (configured)
 160                 zdev->state = ZPCI_FN_STATE_CONFIGURED;
 161         else
 162                 zdev->state = ZPCI_FN_STATE_STANDBY;
 163
 164         rc = zpci_create_device(zdev);
 165         if (rc)
 166                 goto error;
 167         return 0;
 168
 169 error:
 170         zpci_free_device(zdev);
 171         return rc;
 172 }
 173
 174 /*
 175  * Enable/Disable a given PCI function defined by its function handle.
 176  */
 177 static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
 178 {
 179         struct clp_req_rsp_set_pci *rrb;
 180         int rc, retries = 1000;
 181
 182         rrb = clp_alloc_block();
 183         if (!rrb)
 184                 return -ENOMEM;
 185
 186         do {
 187                 memset(rrb, 0, sizeof(*rrb));
 188                 rrb->request.hdr.len = sizeof(rrb->request);
 189                 rrb->request.hdr.cmd = CLP_SET_PCI_FN;
 190                 rrb->response.hdr.len = sizeof(rrb->response);
 191                 rrb->request.fh = *fh;
 192                 rrb->request.oc = command;
 193                 rrb->request.ndas = nr_dma_as;
 194
 195                 rc = clp_instr(rrb);
 196                 if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
 197                         retries--;
 198                         if (retries < 0)
 199                                 break;
 200                         msleep(1);
 201                 }
 202         } while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
 203
 204         if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
 205                 *fh = rrb->response.fh;
 206         else {
 207                 pr_err("Set PCI FN failed with response: %x  cc: %d\n",
 208                         rrb->response.hdr.rsp, rc);
 209                 rc = -EIO;
 210         }
 211         clp_free_block(rrb);
 212         return rc;
 213 }
 214
 215 int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
 216 {
 217         u32 fh = zdev->fh;
 218         int rc;
 219
 220         rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
 221         if (!rc)
 222                 /* Success -> store enabled handle in zdev */
 223                 zdev->fh = fh;
 224         return rc;
 225 }
 226
 227 int clp_disable_fh(struct zpci_dev *zdev)
 228 {
 229         u32 fh = zdev->fh;
 230         int rc;
 231
 232         if (!zdev_enabled(zdev))
 233                 return 0;
 234
 235         dev_info(&zdev->pdev->dev, "disabling fn handle: 0x%x\n", fh);
 236         rc = clp_set_pci_fn(&fh, 0, CLP_SET_DISABLE_PCI_FN);
 237         if (!rc)
 238                 /* Success -> store disabled handle in zdev */
 239                 zdev->fh = fh;
 240         else
 241                 dev_err(&zdev->pdev->dev,
 242                         "Failed to disable fn handle: 0x%x\n", fh);
 243         return rc;
 244 }
 245
 246 static void clp_check_pcifn_entry(struct clp_fh_list_entry *entry)
 247 {
 248         int present, rc;
 249
 250         if (!entry->vendor_id)
 251                 return;
 252
 253         /* TODO: be a little bit more scalable */
 254         present = zpci_fid_present(entry->fid);
 255
 256         if (present)
 257                 pr_debug("%s: device %x already present\n", __func__, entry->fid);
 258
 259         /* skip already used functions */
 260         if (present && entry->config_state)
 261                 return;
 262
 263         /* aev 306: function moved to stand-by state */
 264         if (present && !entry->config_state) {
 265                 /*
 266                  * The handle is already disabled, that means no iota/irq freeing via
 267                  * the firmware interfaces anymore. Need to free resources manually
 268                  * (DMA memory, debug, sysfs)...
 269                  */
 270                 zpci_stop_device(get_zdev_by_fid(entry->fid));
 271                 return;
 272         }
 273
 274         rc = clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
 275         if (rc)
 276                 pr_err("Failed to add fid: 0x%x\n", entry->fid);
 277 }
 278
 279 int clp_find_pci_devices(void)
 280 {
 281         struct clp_req_rsp_list_pci *rrb;
 282         u64 resume_token = 0;
 283         int entries, i, rc;
 284
 285         rrb = clp_alloc_block();
 286         if (!rrb)
 287                 return -ENOMEM;
 288
 289         do {
 290                 memset(rrb, 0, sizeof(*rrb));
 291                 rrb->request.hdr.len = sizeof(rrb->request);
 292                 rrb->request.hdr.cmd = CLP_LIST_PCI;
 293                 /* store as many entries as possible */
 294                 rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
 295                 rrb->request.resume_token = resume_token;
 296
 297                 /* Get PCI function handle list */
 298                 rc = clp_instr(rrb);
 299                 if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
 300                         pr_err("List PCI failed with response: 0x%x  cc: %d\n",
 301                                 rrb->response.hdr.rsp, rc);
 302                         rc = -EIO;
 303                         goto out;
 304                 }
 305
 306                 WARN_ON_ONCE(rrb->response.entry_size !=
 307                         sizeof(struct clp_fh_list_entry));
 308
 309                 entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
 310                         rrb->response.entry_size;
 311                 pr_info("Detected number of PCI functions: %u\n", entries);
 312
 313                 /* Store the returned resume token as input for the next call */
 314                 resume_token = rrb->response.resume_token;
 315
 316                 for (i = 0; i < entries; i++)
 317                         clp_check_pcifn_entry(&rrb->response.fh_list[i]);
 318         } while (resume_token);
 319
 320         pr_debug("Maximum number of supported PCI functions: %u\n",
 321                 rrb->response.max_fn);
 322 out:
 323         clp_free_block(rrb);
 324         return rc;
 325 }