git.librecmc.org Git - oweals/openwrt.git/blob

   1 From cfdf39199781b73840dfdfb7d1281b398c1334cf Mon Sep 17 00:00:00 2001
   2 From: popcornmix <popcornmix@gmail.com>
   3 Date: Fri, 28 Oct 2016 15:36:43 +0100
   4 Subject: [PATCH] vc_mem: Add vc_mem driver for querying firmware
   5  memory addresses
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 Signed-off-by: popcornmix <popcornmix@gmail.com>
  11
  12 BCM270x: Move vc_mem
  13
  14 Make the vc_mem module available for ARCH_BCM2835 by moving it.
  15
  16 Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
  17 ---
  18  drivers/char/broadcom/Kconfig   |  18 ++
  19  drivers/char/broadcom/Makefile  |   1 +
  20  drivers/char/broadcom/vc_mem.c  | 422 ++++++++++++++++++++++++++++++++
  21  include/linux/broadcom/vc_mem.h |  35 +++
  22  4 files changed, 476 insertions(+)
  23  create mode 100644 drivers/char/broadcom/Kconfig
  24  create mode 100644 drivers/char/broadcom/Makefile
  25  create mode 100644 drivers/char/broadcom/vc_mem.c
  26  create mode 100644 include/linux/broadcom/vc_mem.h
  27
  28 --- /dev/null
  29 +++ b/drivers/char/broadcom/Kconfig
  30 @@ -0,0 +1,18 @@
  31 +#
  32 +# Broadcom char driver config
  33 +#
  34 +
  35 +menuconfig BRCM_CHAR_DRIVERS
  36 +       bool "Broadcom Char Drivers"
  37 +       help
  38 +         Broadcom's char drivers
  39 +
  40 +if BRCM_CHAR_DRIVERS
  41 +
  42 +config BCM2708_VCMEM
  43 +       bool "Videocore Memory"
  44 +        default y
  45 +        help
  46 +          Helper for videocore memory access and total size allocation.
  47 +
  48 +endif
  49 --- /dev/null
  50 +++ b/drivers/char/broadcom/Makefile
  51 @@ -0,0 +1 @@
  52 +obj-$(CONFIG_BCM2708_VCMEM)    += vc_mem.o
  53 --- /dev/null
  54 +++ b/drivers/char/broadcom/vc_mem.c
  55 @@ -0,0 +1,422 @@
  56 +/*****************************************************************************
  57 +* Copyright 2010 - 2011 Broadcom Corporation.  All rights reserved.
  58 +*
  59 +* Unless you and Broadcom execute a separate written software license
  60 +* agreement governing use of this software, this software is licensed to you
  61 +* under the terms of the GNU General Public License version 2, available at
  62 +* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
  63 +*
  64 +* Notwithstanding the above, under no circumstances may you combine this
  65 +* software in any way with any other Broadcom software provided under a
  66 +* license other than the GPL, without Broadcom's express prior written
  67 +* consent.
  68 +*****************************************************************************/
  69 +
  70 +#include <linux/kernel.h>
  71 +#include <linux/module.h>
  72 +#include <linux/fs.h>
  73 +#include <linux/device.h>
  74 +#include <linux/cdev.h>
  75 +#include <linux/mm.h>
  76 +#include <linux/slab.h>
  77 +#include <linux/debugfs.h>
  78 +#include <linux/uaccess.h>
  79 +#include <linux/dma-mapping.h>
  80 +#include <linux/broadcom/vc_mem.h>
  81 +
  82 +#define DRIVER_NAME  "vc-mem"
  83 +
  84 +// Device (/dev) related variables
  85 +static dev_t vc_mem_devnum = 0;
  86 +static struct class *vc_mem_class = NULL;
  87 +static struct cdev vc_mem_cdev;
  88 +static int vc_mem_inited = 0;
  89 +
  90 +#ifdef CONFIG_DEBUG_FS
  91 +static struct dentry *vc_mem_debugfs_entry;
  92 +#endif
  93 +
  94 +/*
  95 + * Videocore memory addresses and size
  96 + *
  97 + * Drivers that wish to know the videocore memory addresses and sizes should
  98 + * use these variables instead of the MM_IO_BASE and MM_ADDR_IO defines in
  99 + * headers. This allows the other drivers to not be tied down to a a certain
 100 + * address/size at compile time.
 101 + *
 102 + * In the future, the goal is to have the videocore memory virtual address and
 103 + * size be calculated at boot time rather than at compile time. The decision of
 104 + * where the videocore memory resides and its size would be in the hands of the
 105 + * bootloader (and/or kernel). When that happens, the values of these variables
 106 + * would be calculated and assigned in the init function.
 107 + */
 108 +// in the 2835 VC in mapped above ARM, but ARM has full access to VC space
 109 +unsigned long mm_vc_mem_phys_addr = 0x00000000;
 110 +unsigned int mm_vc_mem_size = 0;
 111 +unsigned int mm_vc_mem_base = 0;
 112 +
 113 +EXPORT_SYMBOL(mm_vc_mem_phys_addr);
 114 +EXPORT_SYMBOL(mm_vc_mem_size);
 115 +EXPORT_SYMBOL(mm_vc_mem_base);
 116 +
 117 +static uint phys_addr = 0;
 118 +static uint mem_size = 0;
 119 +static uint mem_base = 0;
 120 +
 121 +
 122 +/****************************************************************************
 123 +*
 124 +*   vc_mem_open
 125 +*
 126 +***************************************************************************/
 127 +
 128 +static int
 129 +vc_mem_open(struct inode *inode, struct file *file)
 130 +{
 131 +       (void) inode;
 132 +       (void) file;
 133 +
 134 +       pr_debug("%s: called file = 0x%p\n", __func__, file);
 135 +
 136 +       return 0;
 137 +}
 138 +
 139 +/****************************************************************************
 140 +*
 141 +*   vc_mem_release
 142 +*
 143 +***************************************************************************/
 144 +
 145 +static int
 146 +vc_mem_release(struct inode *inode, struct file *file)
 147 +{
 148 +       (void) inode;
 149 +       (void) file;
 150 +
 151 +       pr_debug("%s: called file = 0x%p\n", __func__, file);
 152 +
 153 +       return 0;
 154 +}
 155 +
 156 +/****************************************************************************
 157 +*
 158 +*   vc_mem_get_size
 159 +*
 160 +***************************************************************************/
 161 +
 162 +static void
 163 +vc_mem_get_size(void)
 164 +{
 165 +}
 166 +
 167 +/****************************************************************************
 168 +*
 169 +*   vc_mem_get_base
 170 +*
 171 +***************************************************************************/
 172 +
 173 +static void
 174 +vc_mem_get_base(void)
 175 +{
 176 +}
 177 +
 178 +/****************************************************************************
 179 +*
 180 +*   vc_mem_get_current_size
 181 +*
 182 +***************************************************************************/
 183 +
 184 +int
 185 +vc_mem_get_current_size(void)
 186 +{
 187 +       return mm_vc_mem_size;
 188 +}
 189 +
 190 +EXPORT_SYMBOL_GPL(vc_mem_get_current_size);
 191 +
 192 +/****************************************************************************
 193 +*
 194 +*   vc_mem_ioctl
 195 +*
 196 +***************************************************************************/
 197 +
 198 +static long
 199 +vc_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 200 +{
 201 +       int rc = 0;
 202 +
 203 +       (void) cmd;
 204 +       (void) arg;
 205 +
 206 +       pr_debug("%s: called file = 0x%p\n", __func__, file);
 207 +
 208 +       switch (cmd) {
 209 +       case VC_MEM_IOC_MEM_PHYS_ADDR:
 210 +               {
 211 +                       pr_debug("%s: VC_MEM_IOC_MEM_PHYS_ADDR=0x%p\n",
 212 +                               __func__, (void *) mm_vc_mem_phys_addr);
 213 +
 214 +                       if (copy_to_user((void *) arg, &mm_vc_mem_phys_addr,
 215 +                                        sizeof (mm_vc_mem_phys_addr)) != 0) {
 216 +                               rc = -EFAULT;
 217 +                       }
 218 +                       break;
 219 +               }
 220 +       case VC_MEM_IOC_MEM_SIZE:
 221 +               {
 222 +                       // Get the videocore memory size first
 223 +                       vc_mem_get_size();
 224 +
 225 +                       pr_debug("%s: VC_MEM_IOC_MEM_SIZE=%u\n", __func__,
 226 +                               mm_vc_mem_size);
 227 +
 228 +                       if (copy_to_user((void *) arg, &mm_vc_mem_size,
 229 +                                        sizeof (mm_vc_mem_size)) != 0) {
 230 +                               rc = -EFAULT;
 231 +                       }
 232 +                       break;
 233 +               }
 234 +       case VC_MEM_IOC_MEM_BASE:
 235 +               {
 236 +                       // Get the videocore memory base
 237 +                       vc_mem_get_base();
 238 +
 239 +                       pr_debug("%s: VC_MEM_IOC_MEM_BASE=%u\n", __func__,
 240 +                               mm_vc_mem_base);
 241 +
 242 +                       if (copy_to_user((void *) arg, &mm_vc_mem_base,
 243 +                                        sizeof (mm_vc_mem_base)) != 0) {
 244 +                               rc = -EFAULT;
 245 +                       }
 246 +                       break;
 247 +               }
 248 +       case VC_MEM_IOC_MEM_LOAD:
 249 +               {
 250 +                       // Get the videocore memory base
 251 +                       vc_mem_get_base();
 252 +
 253 +                       pr_debug("%s: VC_MEM_IOC_MEM_LOAD=%u\n", __func__,
 254 +                               mm_vc_mem_base);
 255 +
 256 +                       if (copy_to_user((void *) arg, &mm_vc_mem_base,
 257 +                                        sizeof (mm_vc_mem_base)) != 0) {
 258 +                               rc = -EFAULT;
 259 +                       }
 260 +                       break;
 261 +               }
 262 +       default:
 263 +               {
 264 +                       return -ENOTTY;
 265 +               }
 266 +       }
 267 +       pr_debug("%s: file = 0x%p returning %d\n", __func__, file, rc);
 268 +
 269 +       return rc;
 270 +}
 271 +
 272 +/****************************************************************************
 273 +*
 274 +*   vc_mem_mmap
 275 +*
 276 +***************************************************************************/
 277 +
 278 +static int
 279 +vc_mem_mmap(struct file *filp, struct vm_area_struct *vma)
 280 +{
 281 +       int rc = 0;
 282 +       unsigned long length = vma->vm_end - vma->vm_start;
 283 +       unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
 284 +
 285 +       pr_debug("%s: vm_start = 0x%08lx vm_end = 0x%08lx vm_pgoff = 0x%08lx\n",
 286 +               __func__, (long) vma->vm_start, (long) vma->vm_end,
 287 +               (long) vma->vm_pgoff);
 288 +
 289 +       if (offset + length > mm_vc_mem_size) {
 290 +               pr_err("%s: length %ld is too big\n", __func__, length);
 291 +               return -EINVAL;
 292 +       }
 293 +       // Do not cache the memory map
 294 +       vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 295 +
 296 +       rc = remap_pfn_range(vma, vma->vm_start,
 297 +                            (mm_vc_mem_phys_addr >> PAGE_SHIFT) +
 298 +                            vma->vm_pgoff, length, vma->vm_page_prot);
 299 +       if (rc != 0) {
 300 +               pr_err("%s: remap_pfn_range failed (rc=%d)\n", __func__, rc);
 301 +       }
 302 +
 303 +       return rc;
 304 +}
 305 +
 306 +/****************************************************************************
 307 +*
 308 +*   File Operations for the driver.
 309 +*
 310 +***************************************************************************/
 311 +
 312 +static const struct file_operations vc_mem_fops = {
 313 +       .owner = THIS_MODULE,
 314 +       .open = vc_mem_open,
 315 +       .release = vc_mem_release,
 316 +       .unlocked_ioctl = vc_mem_ioctl,
 317 +       .mmap = vc_mem_mmap,
 318 +};
 319 +
 320 +#ifdef CONFIG_DEBUG_FS
 321 +static void vc_mem_debugfs_deinit(void)
 322 +{
 323 +       debugfs_remove_recursive(vc_mem_debugfs_entry);
 324 +       vc_mem_debugfs_entry = NULL;
 325 +}
 326 +
 327 +
 328 +static int vc_mem_debugfs_init(
 329 +       struct device *dev)
 330 +{
 331 +       vc_mem_debugfs_entry = debugfs_create_dir(DRIVER_NAME, NULL);
 332 +       if (!vc_mem_debugfs_entry) {
 333 +               dev_warn(dev, "could not create debugfs entry\n");
 334 +               return -EFAULT;
 335 +       }
 336 +
 337 +       if (!debugfs_create_x32("vc_mem_phys_addr",
 338 +                               0444,
 339 +                               vc_mem_debugfs_entry,
 340 +                               (u32 *)&mm_vc_mem_phys_addr)) {
 341 +               dev_warn(dev, "%s:could not create vc_mem_phys entry\n",
 342 +                       __func__);
 343 +               goto fail;
 344 +       }
 345 +
 346 +       if (!debugfs_create_x32("vc_mem_size",
 347 +                               0444,
 348 +                               vc_mem_debugfs_entry,
 349 +                               (u32 *)&mm_vc_mem_size)) {
 350 +               dev_warn(dev, "%s:could not create vc_mem_size entry\n",
 351 +                       __func__);
 352 +               goto fail;
 353 +       }
 354 +
 355 +       if (!debugfs_create_x32("vc_mem_base",
 356 +                               0444,
 357 +                               vc_mem_debugfs_entry,
 358 +                               (u32 *)&mm_vc_mem_base)) {
 359 +               dev_warn(dev, "%s:could not create vc_mem_base entry\n",
 360 +                        __func__);
 361 +               goto fail;
 362 +       }
 363 +
 364 +       return 0;
 365 +
 366 +fail:
 367 +       vc_mem_debugfs_deinit();
 368 +       return -EFAULT;
 369 +}
 370 +
 371 +#endif /* CONFIG_DEBUG_FS */
 372 +
 373 +
 374 +/****************************************************************************
 375 +*
 376 +*   vc_mem_init
 377 +*
 378 +***************************************************************************/
 379 +
 380 +static int __init
 381 +vc_mem_init(void)
 382 +{
 383 +       int rc = -EFAULT;
 384 +       struct device *dev;
 385 +
 386 +       pr_debug("%s: called\n", __func__);
 387 +
 388 +       mm_vc_mem_phys_addr = phys_addr;
 389 +       mm_vc_mem_size = mem_size;
 390 +       mm_vc_mem_base = mem_base;
 391 +
 392 +       vc_mem_get_size();
 393 +
 394 +       pr_info("vc-mem: phys_addr:0x%08lx mem_base=0x%08x mem_size:0x%08x(%u MiB)\n",
 395 +               mm_vc_mem_phys_addr, mm_vc_mem_base, mm_vc_mem_size, mm_vc_mem_size / (1024 * 1024));
 396 +
 397 +       if ((rc = alloc_chrdev_region(&vc_mem_devnum, 0, 1, DRIVER_NAME)) < 0) {
 398 +               pr_err("%s: alloc_chrdev_region failed (rc=%d)\n",
 399 +                      __func__, rc);
 400 +               goto out_err;
 401 +       }
 402 +
 403 +       cdev_init(&vc_mem_cdev, &vc_mem_fops);
 404 +       if ((rc = cdev_add(&vc_mem_cdev, vc_mem_devnum, 1)) != 0) {
 405 +               pr_err("%s: cdev_add failed (rc=%d)\n", __func__, rc);
 406 +               goto out_unregister;
 407 +       }
 408 +
 409 +       vc_mem_class = class_create(THIS_MODULE, DRIVER_NAME);
 410 +       if (IS_ERR(vc_mem_class)) {
 411 +               rc = PTR_ERR(vc_mem_class);
 412 +               pr_err("%s: class_create failed (rc=%d)\n", __func__, rc);
 413 +               goto out_cdev_del;
 414 +       }
 415 +
 416 +       dev = device_create(vc_mem_class, NULL, vc_mem_devnum, NULL,
 417 +                           DRIVER_NAME);
 418 +       if (IS_ERR(dev)) {
 419 +               rc = PTR_ERR(dev);
 420 +               pr_err("%s: device_create failed (rc=%d)\n", __func__, rc);
 421 +               goto out_class_destroy;
 422 +       }
 423 +
 424 +#ifdef CONFIG_DEBUG_FS
 425 +       /* don't fail if the debug entries cannot be created */
 426 +       vc_mem_debugfs_init(dev);
 427 +#endif
 428 +
 429 +       vc_mem_inited = 1;
 430 +       return 0;
 431 +
 432 +       device_destroy(vc_mem_class, vc_mem_devnum);
 433 +
 434 +      out_class_destroy:
 435 +       class_destroy(vc_mem_class);
 436 +       vc_mem_class = NULL;
 437 +
 438 +      out_cdev_del:
 439 +       cdev_del(&vc_mem_cdev);
 440 +
 441 +      out_unregister:
 442 +       unregister_chrdev_region(vc_mem_devnum, 1);
 443 +
 444 +      out_err:
 445 +       return -1;
 446 +}
 447 +
 448 +/****************************************************************************
 449 +*
 450 +*   vc_mem_exit
 451 +*
 452 +***************************************************************************/
 453 +
 454 +static void __exit
 455 +vc_mem_exit(void)
 456 +{
 457 +       pr_debug("%s: called\n", __func__);
 458 +
 459 +       if (vc_mem_inited) {
 460 +#if CONFIG_DEBUG_FS
 461 +               vc_mem_debugfs_deinit();
 462 +#endif
 463 +               device_destroy(vc_mem_class, vc_mem_devnum);
 464 +               class_destroy(vc_mem_class);
 465 +               cdev_del(&vc_mem_cdev);
 466 +               unregister_chrdev_region(vc_mem_devnum, 1);
 467 +       }
 468 +}
 469 +
 470 +module_init(vc_mem_init);
 471 +module_exit(vc_mem_exit);
 472 +MODULE_LICENSE("GPL");
 473 +MODULE_AUTHOR("Broadcom Corporation");
 474 +
 475 +module_param(phys_addr, uint, 0644);
 476 +module_param(mem_size, uint, 0644);
 477 +module_param(mem_base, uint, 0644);
 478 --- /dev/null
 479 +++ b/include/linux/broadcom/vc_mem.h
 480 @@ -0,0 +1,35 @@
 481 +/*****************************************************************************
 482 +* Copyright 2010 - 2011 Broadcom Corporation.  All rights reserved.
 483 +*
 484 +* Unless you and Broadcom execute a separate written software license
 485 +* agreement governing use of this software, this software is licensed to you
 486 +* under the terms of the GNU General Public License version 2, available at
 487 +* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
 488 +*
 489 +* Notwithstanding the above, under no circumstances may you combine this
 490 +* software in any way with any other Broadcom software provided under a
 491 +* license other than the GPL, without Broadcom's express prior written
 492 +* consent.
 493 +*****************************************************************************/
 494 +
 495 +#ifndef _VC_MEM_H
 496 +#define _VC_MEM_H
 497 +
 498 +#include <linux/ioctl.h>
 499 +
 500 +#define VC_MEM_IOC_MAGIC  'v'
 501 +
 502 +#define VC_MEM_IOC_MEM_PHYS_ADDR    _IOR( VC_MEM_IOC_MAGIC, 0, unsigned long )
 503 +#define VC_MEM_IOC_MEM_SIZE         _IOR( VC_MEM_IOC_MAGIC, 1, unsigned int )
 504 +#define VC_MEM_IOC_MEM_BASE         _IOR( VC_MEM_IOC_MAGIC, 2, unsigned int )
 505 +#define VC_MEM_IOC_MEM_LOAD         _IOR( VC_MEM_IOC_MAGIC, 3, unsigned int )
 506 +
 507 +#if defined( __KERNEL__ )
 508 +#define VC_MEM_TO_ARM_ADDR_MASK 0x3FFFFFFF
 509 +
 510 +extern unsigned long mm_vc_mem_phys_addr;
 511 +extern unsigned int  mm_vc_mem_size;
 512 +extern int vc_mem_get_current_size( void );
 513 +#endif
 514 +
 515 +#endif  /* _VC_MEM_H */