drivers/edac/cell_edac.c

   1 /*
   2  * Cell MIC driver for ECC counting
   3  *
   4  * Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
   5  *                <benh@kernel.crashing.org>
   6  *
   7  * This file may be distributed under the terms of the
   8  * GNU General Public License.
   9  */
  10 #undef DEBUG
  11
  12 #include <linux/edac.h>
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/stop_machine.h>
  17 #include <linux/io.h>
  18 #include <linux/of_address.h>
  19 #include <asm/machdep.h>
  20 #include <asm/cell-regs.h>
  21
  22 #include "edac_core.h"
  23
  24 struct cell_edac_priv
  25 {
  26         struct cbe_mic_tm_regs __iomem  *regs;
  27         int                             node;
  28         int                             chanmask;
  29 #ifdef DEBUG
  30         u64                             prev_fir;
  31 #endif
  32 };
  33
  34 static void cell_edac_count_ce(struct mem_ctl_info *mci, int chan, u64 ar)
  35 {
  36         struct cell_edac_priv           *priv = mci->pvt_info;
  37         struct csrow_info               *csrow = mci->csrows[0];
  38         unsigned long                   address, pfn, offset, syndrome;
  39
  40         dev_dbg(mci->pdev, "ECC CE err on node %d, channel %d, ar = 0x%016llx\n",
  41                 priv->node, chan, ar);
  42
  43         /* Address decoding is likely a bit bogus, to dbl check */
  44         address = (ar & 0xffffffffe0000000ul) >> 29;
  45         if (priv->chanmask == 0x3)
  46                 address = (address << 1) | chan;
  47         pfn = address >> PAGE_SHIFT;
  48         offset = address & ~PAGE_MASK;
  49         syndrome = (ar & 0x000000001fe00000ul) >> 21;
  50
  51         /* TODO: Decoding of the error address */
  52         edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
  53                              csrow->first_page + pfn, offset, syndrome,
  54                              0, chan, -1, "", "");
  55 }
  56
  57 static void cell_edac_count_ue(struct mem_ctl_info *mci, int chan, u64 ar)
  58 {
  59         struct cell_edac_priv           *priv = mci->pvt_info;
  60         struct csrow_info               *csrow = mci->csrows[0];
  61         unsigned long                   address, pfn, offset;
  62
  63         dev_dbg(mci->pdev, "ECC UE err on node %d, channel %d, ar = 0x%016llx\n",
  64                 priv->node, chan, ar);
  65
  66         /* Address decoding is likely a bit bogus, to dbl check */
  67         address = (ar & 0xffffffffe0000000ul) >> 29;
  68         if (priv->chanmask == 0x3)
  69                 address = (address << 1) | chan;
  70         pfn = address >> PAGE_SHIFT;
  71         offset = address & ~PAGE_MASK;
  72
  73         /* TODO: Decoding of the error address */
  74         edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
  75                              csrow->first_page + pfn, offset, 0,
  76                              0, chan, -1, "", "");
  77 }
  78
  79 static void cell_edac_check(struct mem_ctl_info *mci)
  80 {
  81         struct cell_edac_priv           *priv = mci->pvt_info;
  82         u64                             fir, addreg, clear = 0;
  83
  84         fir = in_be64(&priv->regs->mic_fir);
  85 #ifdef DEBUG
  86         if (fir != priv->prev_fir) {
  87                 dev_dbg(mci->pdev, "fir change : 0x%016lx\n", fir);
  88                 priv->prev_fir = fir;
  89         }
  90 #endif
  91         if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_SINGLE_0_ERR)) {
  92                 addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
  93                 clear |= CBE_MIC_FIR_ECC_SINGLE_0_RESET;
  94                 cell_edac_count_ce(mci, 0, addreg);
  95         }
  96         if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_SINGLE_1_ERR)) {
  97                 addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
  98                 clear |= CBE_MIC_FIR_ECC_SINGLE_1_RESET;
  99                 cell_edac_count_ce(mci, 1, addreg);
 100         }
 101         if ((priv->chanmask & 0x1) && (fir & CBE_MIC_FIR_ECC_MULTI_0_ERR)) {
 102                 addreg = in_be64(&priv->regs->mic_df_ecc_address_0);
 103                 clear |= CBE_MIC_FIR_ECC_MULTI_0_RESET;
 104                 cell_edac_count_ue(mci, 0, addreg);
 105         }
 106         if ((priv->chanmask & 0x2) && (fir & CBE_MIC_FIR_ECC_MULTI_1_ERR)) {
 107                 addreg = in_be64(&priv->regs->mic_df_ecc_address_1);
 108                 clear |= CBE_MIC_FIR_ECC_MULTI_1_RESET;
 109                 cell_edac_count_ue(mci, 1, addreg);
 110         }
 111
 112         /* The procedure for clearing FIR bits is a bit ... weird */
 113         if (clear) {
 114                 fir &= ~(CBE_MIC_FIR_ECC_ERR_MASK | CBE_MIC_FIR_ECC_SET_MASK);
 115                 fir |= CBE_MIC_FIR_ECC_RESET_MASK;
 116                 fir &= ~clear;
 117                 out_be64(&priv->regs->mic_fir, fir);
 118                 (void)in_be64(&priv->regs->mic_fir);
 119
 120                 mb();   /* sync up */
 121 #ifdef DEBUG
 122                 fir = in_be64(&priv->regs->mic_fir);
 123                 dev_dbg(mci->pdev, "fir clear  : 0x%016lx\n", fir);
 124 #endif
 125         }
 126 }
 127
 128 static void cell_edac_init_csrows(struct mem_ctl_info *mci)
 129 {
 130         struct csrow_info               *csrow = mci->csrows[0];
 131         struct dimm_info                *dimm;
 132         struct cell_edac_priv           *priv = mci->pvt_info;
 133         struct device_node              *np;
 134         int                             j;
 135         u32                             nr_pages;
 136
 137         for (np = NULL;
 138              (np = of_find_node_by_name(np, "memory")) != NULL;) {
 139                 struct resource r;
 140
 141                 /* We "know" that the Cell firmware only creates one entry
 142                  * in the "memory" nodes. If that changes, this code will
 143                  * need to be adapted.
 144                  */
 145                 if (of_address_to_resource(np, 0, &r))
 146                         continue;
 147                 if (of_node_to_nid(np) != priv->node)
 148                         continue;
 149                 csrow->first_page = r.start >> PAGE_SHIFT;
 150                 nr_pages = resource_size(&r) >> PAGE_SHIFT;
 151                 csrow->last_page = csrow->first_page + nr_pages - 1;
 152
 153                 for (j = 0; j < csrow->nr_channels; j++) {
 154                         dimm = csrow->channels[j]->dimm;
 155                         dimm->mtype = MEM_XDR;
 156                         dimm->edac_mode = EDAC_SECDED;
 157                         dimm->nr_pages = nr_pages / csrow->nr_channels;
 158                 }
 159                 dev_dbg(mci->pdev,
 160                         "Initialized on node %d, chanmask=0x%x,"
 161                         " first_page=0x%lx, nr_pages=0x%x\n",
 162                         priv->node, priv->chanmask,
 163                         csrow->first_page, nr_pages);
 164                 break;
 165         }
 166         of_node_put(np);
 167 }
 168
 169 static int cell_edac_probe(struct platform_device *pdev)
 170 {
 171         struct cbe_mic_tm_regs __iomem  *regs;
 172         struct mem_ctl_info             *mci;
 173         struct edac_mc_layer            layers[2];
 174         struct cell_edac_priv           *priv;
 175         u64                             reg;
 176         int                             rc, chanmask, num_chans;
 177
 178         regs = cbe_get_cpu_mic_tm_regs(cbe_node_to_cpu(pdev->id));
 179         if (regs == NULL)
 180                 return -ENODEV;
 181
 182         edac_op_state = EDAC_OPSTATE_POLL;
 183
 184         /* Get channel population */
 185         reg = in_be64(&regs->mic_mnt_cfg);
 186         dev_dbg(&pdev->dev, "MIC_MNT_CFG = 0x%016llx\n", reg);
 187         chanmask = 0;
 188         if (reg & CBE_MIC_MNT_CFG_CHAN_0_POP)
 189                 chanmask |= 0x1;
 190         if (reg & CBE_MIC_MNT_CFG_CHAN_1_POP)
 191                 chanmask |= 0x2;
 192         if (chanmask == 0) {
 193                 dev_warn(&pdev->dev,
 194                          "Yuck ! No channel populated ? Aborting !\n");
 195                 return -ENODEV;
 196         }
 197         dev_dbg(&pdev->dev, "Initial FIR = 0x%016llx\n",
 198                 in_be64(&regs->mic_fir));
 199
 200         /* Allocate & init EDAC MC data structure */
 201         num_chans = chanmask == 3 ? 2 : 1;
 202
 203         layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
 204         layers[0].size = 1;
 205         layers[0].is_virt_csrow = true;
 206         layers[1].type = EDAC_MC_LAYER_CHANNEL;
 207         layers[1].size = num_chans;
 208         layers[1].is_virt_csrow = false;
 209         mci = edac_mc_alloc(pdev->id, ARRAY_SIZE(layers), layers,
 210                             sizeof(struct cell_edac_priv));
 211         if (mci == NULL)
 212                 return -ENOMEM;
 213         priv = mci->pvt_info;
 214         priv->regs = regs;
 215         priv->node = pdev->id;
 216         priv->chanmask = chanmask;
 217         mci->pdev = &pdev->dev;
 218         mci->mtype_cap = MEM_FLAG_XDR;
 219         mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
 220         mci->edac_cap = EDAC_FLAG_EC | EDAC_FLAG_SECDED;
 221         mci->mod_name = "cell_edac";
 222         mci->ctl_name = "MIC";
 223         mci->dev_name = dev_name(&pdev->dev);
 224         mci->edac_check = cell_edac_check;
 225         cell_edac_init_csrows(mci);
 226
 227         /* Register with EDAC core */
 228         rc = edac_mc_add_mc(mci);
 229         if (rc) {
 230                 dev_err(&pdev->dev, "failed to register with EDAC core\n");
 231                 edac_mc_free(mci);
 232                 return rc;
 233         }
 234
 235         return 0;
 236 }
 237
 238 static int cell_edac_remove(struct platform_device *pdev)
 239 {
 240         struct mem_ctl_info *mci = edac_mc_del_mc(&pdev->dev);
 241         if (mci)
 242                 edac_mc_free(mci);
 243         return 0;
 244 }
 245
 246 static struct platform_driver cell_edac_driver = {
 247         .driver         = {
 248                 .name   = "cbe-mic",
 249                 .owner  = THIS_MODULE,
 250         },
 251         .probe          = cell_edac_probe,
 252         .remove         = cell_edac_remove,
 253 };
 254
 255 static int __init cell_edac_init(void)
 256 {
 257         /* Sanity check registers data structure */
 258         BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
 259                               mic_df_ecc_address_0) != 0xf8);
 260         BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
 261                               mic_df_ecc_address_1) != 0x1b8);
 262         BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
 263                               mic_df_config) != 0x218);
 264         BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
 265                               mic_fir) != 0x230);
 266         BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
 267                               mic_mnt_cfg) != 0x210);
 268         BUILD_BUG_ON(offsetof(struct cbe_mic_tm_regs,
 269                               mic_exc) != 0x208);
 270
 271         return platform_driver_register(&cell_edac_driver);
 272 }
 273
 274 static void __exit cell_edac_exit(void)
 275 {
 276         platform_driver_unregister(&cell_edac_driver);
 277 }
 278
 279 module_init(cell_edac_init);
 280 module_exit(cell_edac_exit);
 281
 282 MODULE_LICENSE("GPL");
 283 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
 284 MODULE_DESCRIPTION("ECC counting for Cell MIC");