drivers/hwtracing/coresight/coresight-tmc.c

   1 /* Copyright (c) 2012, The Linux Foundation. All rights reserved.
   2  *
   3  * Description: CoreSight Trace Memory Controller driver
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 and
   7  * only version 2 as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/init.h>
  17 #include <linux/types.h>
  18 #include <linux/device.h>
  19 #include <linux/io.h>
  20 #include <linux/err.h>
  21 #include <linux/fs.h>
  22 #include <linux/miscdevice.h>
  23 #include <linux/uaccess.h>
  24 #include <linux/slab.h>
  25 #include <linux/dma-mapping.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/pm_runtime.h>
  28 #include <linux/of.h>
  29 #include <linux/coresight.h>
  30 #include <linux/amba/bus.h>
  31
  32 #include "coresight-priv.h"
  33 #include "coresight-tmc.h"
  34
  35 void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata)
  36 {
  37         /* Ensure formatter, unformatter and hardware fifo are empty */
  38         if (coresight_timeout(drvdata->base,
  39                               TMC_STS, TMC_STS_TMCREADY_BIT, 1)) {
  40                 dev_err(drvdata->dev,
  41                         "timeout observed when probing at offset %#x\n",
  42                         TMC_STS);
  43         }
  44 }
  45
  46 void tmc_flush_and_stop(struct tmc_drvdata *drvdata)
  47 {
  48         u32 ffcr;
  49
  50         ffcr = readl_relaxed(drvdata->base + TMC_FFCR);
  51         ffcr |= TMC_FFCR_STOP_ON_FLUSH;
  52         writel_relaxed(ffcr, drvdata->base + TMC_FFCR);
  53         ffcr |= BIT(TMC_FFCR_FLUSHMAN_BIT);
  54         writel_relaxed(ffcr, drvdata->base + TMC_FFCR);
  55         /* Ensure flush completes */
  56         if (coresight_timeout(drvdata->base,
  57                               TMC_FFCR, TMC_FFCR_FLUSHMAN_BIT, 0)) {
  58                 dev_err(drvdata->dev,
  59                         "timeout observed when probing at offset %#x\n",
  60                         TMC_FFCR);
  61         }
  62
  63         tmc_wait_for_tmcready(drvdata);
  64 }
  65
  66 void tmc_enable_hw(struct tmc_drvdata *drvdata)
  67 {
  68         writel_relaxed(TMC_CTL_CAPT_EN, drvdata->base + TMC_CTL);
  69 }
  70
  71 void tmc_disable_hw(struct tmc_drvdata *drvdata)
  72 {
  73         writel_relaxed(0x0, drvdata->base + TMC_CTL);
  74 }
  75
  76 static int tmc_read_prepare(struct tmc_drvdata *drvdata)
  77 {
  78         int ret = 0;
  79
  80         switch (drvdata->config_type) {
  81         case TMC_CONFIG_TYPE_ETB:
  82         case TMC_CONFIG_TYPE_ETF:
  83                 ret = tmc_read_prepare_etb(drvdata);
  84                 break;
  85         case TMC_CONFIG_TYPE_ETR:
  86                 ret = tmc_read_prepare_etr(drvdata);
  87                 break;
  88         default:
  89                 ret = -EINVAL;
  90         }
  91
  92         if (!ret)
  93                 dev_info(drvdata->dev, "TMC read start\n");
  94
  95         return ret;
  96 }
  97
  98 static void tmc_read_unprepare(struct tmc_drvdata *drvdata)
  99 {
 100         int ret = 0;
 101
 102         switch (drvdata->config_type) {
 103         case TMC_CONFIG_TYPE_ETB:
 104         case TMC_CONFIG_TYPE_ETF:
 105                 ret = tmc_read_unprepare_etb(drvdata);
 106                 break;
 107         case TMC_CONFIG_TYPE_ETR:
 108                 ret = tmc_read_unprepare_etr(drvdata);
 109                 break;
 110         default:
 111                 ret = -EINVAL;
 112         }
 113
 114         if (!ret)
 115                 dev_info(drvdata->dev, "TMC read end\n");
 116 }
 117
 118 static int tmc_open(struct inode *inode, struct file *file)
 119 {
 120         struct tmc_drvdata *drvdata = container_of(file->private_data,
 121                                                    struct tmc_drvdata, miscdev);
 122         int ret = 0;
 123
 124         if (drvdata->read_count++)
 125                 goto out;
 126
 127         ret = tmc_read_prepare(drvdata);
 128         if (ret)
 129                 return ret;
 130 out:
 131         nonseekable_open(inode, file);
 132
 133         dev_dbg(drvdata->dev, "%s: successfully opened\n", __func__);
 134         return 0;
 135 }
 136
 137 static ssize_t tmc_read(struct file *file, char __user *data, size_t len,
 138                         loff_t *ppos)
 139 {
 140         struct tmc_drvdata *drvdata = container_of(file->private_data,
 141                                                    struct tmc_drvdata, miscdev);
 142         char *bufp = drvdata->buf + *ppos;
 143
 144         if (*ppos + len > drvdata->size)
 145                 len = drvdata->size - *ppos;
 146
 147         if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) {
 148                 if (bufp == (char *)(drvdata->vaddr + drvdata->size))
 149                         bufp = drvdata->vaddr;
 150                 else if (bufp > (char *)(drvdata->vaddr + drvdata->size))
 151                         bufp -= drvdata->size;
 152                 if ((bufp + len) > (char *)(drvdata->vaddr + drvdata->size))
 153                         len = (char *)(drvdata->vaddr + drvdata->size) - bufp;
 154         }
 155
 156         if (copy_to_user(data, bufp, len)) {
 157                 dev_dbg(drvdata->dev, "%s: copy_to_user failed\n", __func__);
 158                 return -EFAULT;
 159         }
 160
 161         *ppos += len;
 162
 163         dev_dbg(drvdata->dev, "%s: %zu bytes copied, %d bytes left\n",
 164                 __func__, len, (int)(drvdata->size - *ppos));
 165         return len;
 166 }
 167
 168 static int tmc_release(struct inode *inode, struct file *file)
 169 {
 170         struct tmc_drvdata *drvdata = container_of(file->private_data,
 171                                                    struct tmc_drvdata, miscdev);
 172
 173         if (--drvdata->read_count) {
 174                 if (drvdata->read_count < 0) {
 175                         dev_err(drvdata->dev, "mismatched close\n");
 176                         drvdata->read_count = 0;
 177                 }
 178                 goto out;
 179         }
 180
 181         tmc_read_unprepare(drvdata);
 182 out:
 183         dev_dbg(drvdata->dev, "%s: released\n", __func__);
 184         return 0;
 185 }
 186
 187 static const struct file_operations tmc_fops = {
 188         .owner          = THIS_MODULE,
 189         .open           = tmc_open,
 190         .read           = tmc_read,
 191         .release        = tmc_release,
 192         .llseek         = no_llseek,
 193 };
 194
 195 #define coresight_tmc_simple_func(name, offset)                 \
 196         coresight_simple_func(struct tmc_drvdata, name, offset)
 197
 198 coresight_tmc_simple_func(rsz, TMC_RSZ);
 199 coresight_tmc_simple_func(sts, TMC_STS);
 200 coresight_tmc_simple_func(rrp, TMC_RRP);
 201 coresight_tmc_simple_func(rwp, TMC_RWP);
 202 coresight_tmc_simple_func(trg, TMC_TRG);
 203 coresight_tmc_simple_func(ctl, TMC_CTL);
 204 coresight_tmc_simple_func(ffsr, TMC_FFSR);
 205 coresight_tmc_simple_func(ffcr, TMC_FFCR);
 206 coresight_tmc_simple_func(mode, TMC_MODE);
 207 coresight_tmc_simple_func(pscr, TMC_PSCR);
 208 coresight_tmc_simple_func(devid, CORESIGHT_DEVID);
 209
 210 static struct attribute *coresight_tmc_mgmt_attrs[] = {
 211         &dev_attr_rsz.attr,
 212         &dev_attr_sts.attr,
 213         &dev_attr_rrp.attr,
 214         &dev_attr_rwp.attr,
 215         &dev_attr_trg.attr,
 216         &dev_attr_ctl.attr,
 217         &dev_attr_ffsr.attr,
 218         &dev_attr_ffcr.attr,
 219         &dev_attr_mode.attr,
 220         &dev_attr_pscr.attr,
 221         &dev_attr_devid.attr,
 222         NULL,
 223 };
 224
 225 ssize_t trigger_cntr_show(struct device *dev,
 226                           struct device_attribute *attr, char *buf)
 227 {
 228         struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
 229         unsigned long val = drvdata->trigger_cntr;
 230
 231         return sprintf(buf, "%#lx\n", val);
 232 }
 233
 234 static ssize_t trigger_cntr_store(struct device *dev,
 235                              struct device_attribute *attr,
 236                              const char *buf, size_t size)
 237 {
 238         int ret;
 239         unsigned long val;
 240         struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
 241
 242         ret = kstrtoul(buf, 16, &val);
 243         if (ret)
 244                 return ret;
 245
 246         drvdata->trigger_cntr = val;
 247         return size;
 248 }
 249 static DEVICE_ATTR_RW(trigger_cntr);
 250
 251 static struct attribute *coresight_tmc_attrs[] = {
 252         &dev_attr_trigger_cntr.attr,
 253         NULL,
 254 };
 255
 256 static const struct attribute_group coresight_tmc_group = {
 257         .attrs = coresight_tmc_attrs,
 258 };
 259
 260 static const struct attribute_group coresight_tmc_mgmt_group = {
 261         .attrs = coresight_tmc_mgmt_attrs,
 262         .name = "mgmt",
 263 };
 264
 265 const struct attribute_group *coresight_tmc_groups[] = {
 266         &coresight_tmc_group,
 267         &coresight_tmc_mgmt_group,
 268         NULL,
 269 };
 270
 271 static int tmc_probe(struct amba_device *adev, const struct amba_id *id)
 272 {
 273         int ret = 0;
 274         u32 devid;
 275         void __iomem *base;
 276         struct device *dev = &adev->dev;
 277         struct coresight_platform_data *pdata = NULL;
 278         struct tmc_drvdata *drvdata;
 279         struct resource *res = &adev->res;
 280         struct coresight_desc *desc;
 281         struct device_node *np = adev->dev.of_node;
 282
 283         if (np) {
 284                 pdata = of_get_coresight_platform_data(dev, np);
 285                 if (IS_ERR(pdata))
 286                         return PTR_ERR(pdata);
 287                 adev->dev.platform_data = pdata;
 288         }
 289
 290         drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
 291         if (!drvdata)
 292                 return -ENOMEM;
 293
 294         drvdata->dev = &adev->dev;
 295         dev_set_drvdata(dev, drvdata);
 296
 297         /* Validity for the resource is already checked by the AMBA core */
 298         base = devm_ioremap_resource(dev, res);
 299         if (IS_ERR(base))
 300                 return PTR_ERR(base);
 301
 302         drvdata->base = base;
 303
 304         spin_lock_init(&drvdata->spinlock);
 305
 306         devid = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
 307         drvdata->config_type = BMVAL(devid, 6, 7);
 308
 309         if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) {
 310                 if (np)
 311                         ret = of_property_read_u32(np,
 312                                                    "arm,buffer-size",
 313                                                    &drvdata->size);
 314                 if (ret)
 315                         drvdata->size = SZ_1M;
 316         } else {
 317                 drvdata->size = readl_relaxed(drvdata->base + TMC_RSZ) * 4;
 318         }
 319
 320         pm_runtime_put(&adev->dev);
 321
 322         if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) {
 323                 drvdata->vaddr = dma_alloc_coherent(dev, drvdata->size,
 324                                                 &drvdata->paddr, GFP_KERNEL);
 325                 if (!drvdata->vaddr)
 326                         return -ENOMEM;
 327
 328                 memset(drvdata->vaddr, 0, drvdata->size);
 329                 drvdata->buf = drvdata->vaddr;
 330         } else {
 331                 drvdata->buf = devm_kzalloc(dev, drvdata->size, GFP_KERNEL);
 332                 if (!drvdata->buf)
 333                         return -ENOMEM;
 334         }
 335
 336         desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
 337         if (!desc) {
 338                 ret = -ENOMEM;
 339                 goto err_devm_kzalloc;
 340         }
 341
 342         desc->pdata = pdata;
 343         desc->dev = dev;
 344         desc->subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER;
 345         desc->groups = coresight_tmc_groups;
 346
 347         if (drvdata->config_type == TMC_CONFIG_TYPE_ETB) {
 348                 desc->type = CORESIGHT_DEV_TYPE_SINK;
 349                 desc->ops = &tmc_etb_cs_ops;
 350         } else if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) {
 351                 desc->type = CORESIGHT_DEV_TYPE_SINK;
 352                 desc->ops = &tmc_etr_cs_ops;
 353         } else {
 354                 desc->type = CORESIGHT_DEV_TYPE_LINKSINK;
 355                 desc->subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_FIFO;
 356                 desc->ops = &tmc_etf_cs_ops;
 357         }
 358
 359         drvdata->csdev = coresight_register(desc);
 360         if (IS_ERR(drvdata->csdev)) {
 361                 ret = PTR_ERR(drvdata->csdev);
 362                 goto err_devm_kzalloc;
 363         }
 364
 365         drvdata->miscdev.name = pdata->name;
 366         drvdata->miscdev.minor = MISC_DYNAMIC_MINOR;
 367         drvdata->miscdev.fops = &tmc_fops;
 368         ret = misc_register(&drvdata->miscdev);
 369         if (ret)
 370                 goto err_misc_register;
 371
 372         return 0;
 373
 374 err_misc_register:
 375         coresight_unregister(drvdata->csdev);
 376 err_devm_kzalloc:
 377         if (drvdata->config_type == TMC_CONFIG_TYPE_ETR)
 378                 dma_free_coherent(dev, drvdata->size,
 379                                 drvdata->vaddr, drvdata->paddr);
 380         return ret;
 381 }
 382
 383 static struct amba_id tmc_ids[] = {
 384         {
 385                 .id     = 0x0003b961,
 386                 .mask   = 0x0003ffff,
 387         },
 388         { 0, 0},
 389 };
 390
 391 static struct amba_driver tmc_driver = {
 392         .drv = {
 393                 .name   = "coresight-tmc",
 394                 .owner  = THIS_MODULE,
 395                 .suppress_bind_attrs = true,
 396         },
 397         .probe          = tmc_probe,
 398         .id_table       = tmc_ids,
 399 };
 400 builtin_amba_driver(tmc_driver);