drivers/fmc/fmc-sdb.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2012 CERN (www.cern.ch)
   4  * Author: Alessandro Rubini <rubini@gnudd.com>
   5  *
   6  * This work is part of the White Rabbit project, a research effort led
   7  * by CERN, the European Institute for Nuclear Research.
   8  */
   9 #include <linux/module.h>
  10 #include <linux/slab.h>
  11 #include <linux/fmc.h>
  12 #include <linux/sdb.h>
  13 #include <linux/err.h>
  14 #include <linux/fmc-sdb.h>
  15 #include <asm/byteorder.h>
  16
  17 static uint32_t __sdb_rd(struct fmc_device *fmc, unsigned long address,
  18                         int convert)
  19 {
  20         uint32_t res = fmc_readl(fmc, address);
  21         if (convert)
  22                 return __be32_to_cpu(res);
  23         return res;
  24 }
  25
  26 static struct sdb_array *__fmc_scan_sdb_tree(struct fmc_device *fmc,
  27                                              unsigned long sdb_addr,
  28                                              unsigned long reg_base, int level)
  29 {
  30         uint32_t onew;
  31         int i, j, n, convert = 0;
  32         struct sdb_array *arr, *sub;
  33
  34         onew = fmc_readl(fmc, sdb_addr);
  35         if (onew == SDB_MAGIC) {
  36                 /* Uh! If we are little-endian, we must convert */
  37                 if (SDB_MAGIC != __be32_to_cpu(SDB_MAGIC))
  38                         convert = 1;
  39         } else if (onew == __be32_to_cpu(SDB_MAGIC)) {
  40                 /* ok, don't convert */
  41         } else {
  42                 return ERR_PTR(-ENOENT);
  43         }
  44         /* So, the magic was there: get the count from offset 4*/
  45         onew = __sdb_rd(fmc, sdb_addr + 4, convert);
  46         n = __be16_to_cpu(*(uint16_t *)&onew);
  47         arr = kzalloc(sizeof(*arr), GFP_KERNEL);
  48         if (!arr)
  49                 return ERR_PTR(-ENOMEM);
  50         arr->record = kcalloc(n, sizeof(arr->record[0]), GFP_KERNEL);
  51         arr->subtree = kcalloc(n, sizeof(arr->subtree[0]), GFP_KERNEL);
  52         if (!arr->record || !arr->subtree) {
  53                 kfree(arr->record);
  54                 kfree(arr->subtree);
  55                 kfree(arr);
  56                 return ERR_PTR(-ENOMEM);
  57         }
  58
  59         arr->len = n;
  60         arr->level = level;
  61         arr->fmc = fmc;
  62         for (i = 0; i < n; i++) {
  63                 union  sdb_record *r;
  64
  65                 for (j = 0; j < sizeof(arr->record[0]); j += 4) {
  66                         *(uint32_t *)((void *)(arr->record + i) + j) =
  67                                 __sdb_rd(fmc, sdb_addr + (i * 64) + j, convert);
  68                 }
  69                 r = &arr->record[i];
  70                 arr->subtree[i] = ERR_PTR(-ENODEV);
  71                 if (r->empty.record_type == sdb_type_bridge) {
  72                         struct sdb_component *c = &r->bridge.sdb_component;
  73                         uint64_t subaddr = __be64_to_cpu(r->bridge.sdb_child);
  74                         uint64_t newbase = __be64_to_cpu(c->addr_first);
  75
  76                         subaddr += reg_base;
  77                         newbase += reg_base;
  78                         sub = __fmc_scan_sdb_tree(fmc, subaddr, newbase,
  79                                                   level + 1);
  80                         arr->subtree[i] = sub; /* may be error */
  81                         if (IS_ERR(sub))
  82                                 continue;
  83                         sub->parent = arr;
  84                         sub->baseaddr = newbase;
  85                 }
  86         }
  87         return arr;
  88 }
  89
  90 int fmc_scan_sdb_tree(struct fmc_device *fmc, unsigned long address)
  91 {
  92         struct sdb_array *ret;
  93         if (fmc->sdb)
  94                 return -EBUSY;
  95         ret = __fmc_scan_sdb_tree(fmc, address, 0 /* regs */, 0);
  96         if (IS_ERR(ret))
  97                 return PTR_ERR(ret);
  98         fmc->sdb = ret;
  99         return 0;
 100 }
 101 EXPORT_SYMBOL(fmc_scan_sdb_tree);
 102
 103 static void __fmc_sdb_free(struct sdb_array *arr)
 104 {
 105         int i, n;
 106
 107         if (!arr)
 108                 return;
 109         n = arr->len;
 110         for (i = 0; i < n; i++) {
 111                 if (IS_ERR(arr->subtree[i]))
 112                         continue;
 113                 __fmc_sdb_free(arr->subtree[i]);
 114         }
 115         kfree(arr->record);
 116         kfree(arr->subtree);
 117         kfree(arr);
 118 }
 119
 120 int fmc_free_sdb_tree(struct fmc_device *fmc)
 121 {
 122         __fmc_sdb_free(fmc->sdb);
 123         fmc->sdb = NULL;
 124         return 0;
 125 }
 126 EXPORT_SYMBOL(fmc_free_sdb_tree);
 127
 128 /* This helper calls reprogram and inizialized sdb as well */
 129 int fmc_reprogram_raw(struct fmc_device *fmc, struct fmc_driver *d,
 130                       void *gw, unsigned long len, int sdb_entry)
 131 {
 132         int ret;
 133
 134         ret = fmc->op->reprogram_raw(fmc, d, gw, len);
 135         if (ret < 0)
 136                 return ret;
 137         if (sdb_entry < 0)
 138                 return ret;
 139
 140         /* We are required to find SDB at a given offset */
 141         ret = fmc_scan_sdb_tree(fmc, sdb_entry);
 142         if (ret < 0) {
 143                 dev_err(&fmc->dev, "Can't find SDB at address 0x%x\n",
 144                         sdb_entry);
 145                 return -ENODEV;
 146         }
 147
 148         return 0;
 149 }
 150 EXPORT_SYMBOL(fmc_reprogram_raw);
 151
 152 /* This helper calls reprogram and inizialized sdb as well */
 153 int fmc_reprogram(struct fmc_device *fmc, struct fmc_driver *d, char *gw,
 154                          int sdb_entry)
 155 {
 156         int ret;
 157
 158         ret = fmc->op->reprogram(fmc, d, gw);
 159         if (ret < 0)
 160                 return ret;
 161         if (sdb_entry < 0)
 162                 return ret;
 163
 164         /* We are required to find SDB at a given offset */
 165         ret = fmc_scan_sdb_tree(fmc, sdb_entry);
 166         if (ret < 0) {
 167                 dev_err(&fmc->dev, "Can't find SDB at address 0x%x\n",
 168                         sdb_entry);
 169                 return -ENODEV;
 170         }
 171
 172         return 0;
 173 }
 174 EXPORT_SYMBOL(fmc_reprogram);
 175
 176 void fmc_show_sdb_tree(const struct fmc_device *fmc)
 177 {
 178         pr_err("%s: not supported anymore, use debugfs to dump SDB\n",
 179                 __func__);
 180 }
 181 EXPORT_SYMBOL(fmc_show_sdb_tree);
 182
 183 signed long fmc_find_sdb_device(struct sdb_array *tree,
 184                                 uint64_t vid, uint32_t did, unsigned long *sz)
 185 {
 186         signed long res = -ENODEV;
 187         union  sdb_record *r;
 188         struct sdb_product *p;
 189         struct sdb_component *c;
 190         int i, n = tree->len;
 191         uint64_t last, first;
 192
 193         /* FIXME: what if the first interconnect is not at zero? */
 194         for (i = 0; i < n; i++) {
 195                 r = &tree->record[i];
 196                 c = &r->dev.sdb_component;
 197                 p = &c->product;
 198
 199                 if (!IS_ERR(tree->subtree[i]))
 200                         res = fmc_find_sdb_device(tree->subtree[i],
 201                                                   vid, did, sz);
 202                 if (res >= 0)
 203                         return res + tree->baseaddr;
 204                 if (r->empty.record_type != sdb_type_device)
 205                         continue;
 206                 if (__be64_to_cpu(p->vendor_id) != vid)
 207                         continue;
 208                 if (__be32_to_cpu(p->device_id) != did)
 209                         continue;
 210                 /* found */
 211                 last = __be64_to_cpu(c->addr_last);
 212                 first = __be64_to_cpu(c->addr_first);
 213                 if (sz)
 214                         *sz = (typeof(*sz))(last + 1 - first);
 215                 return first + tree->baseaddr;
 216         }
 217         return res;
 218 }
 219 EXPORT_SYMBOL(fmc_find_sdb_device);