include/drm/drm_os_linux.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /**
   3  * \file drm_os_linux.h
   4  * OS abstraction macros.
   5  */
   6
   7 #include <linux/interrupt.h>    /* For task queue support */
   8 #include <linux/sched/signal.h>
   9 #include <linux/delay.h>
  10 #include <linux/io-64-nonatomic-lo-hi.h>
  11
  12 /** Current process ID */
  13 #define DRM_CURRENTPID                  task_pid_nr(current)
  14 #define DRM_UDELAY(d)                   udelay(d)
  15 /** Read a byte from a MMIO region */
  16 #define DRM_READ8(map, offset)          readb(((void __iomem *)(map)->handle) + (offset))
  17 /** Read a word from a MMIO region */
  18 #define DRM_READ16(map, offset)         readw(((void __iomem *)(map)->handle) + (offset))
  19 /** Read a dword from a MMIO region */
  20 #define DRM_READ32(map, offset)         readl(((void __iomem *)(map)->handle) + (offset))
  21 /** Write a byte into a MMIO region */
  22 #define DRM_WRITE8(map, offset, val)    writeb(val, ((void __iomem *)(map)->handle) + (offset))
  23 /** Write a word into a MMIO region */
  24 #define DRM_WRITE16(map, offset, val)   writew(val, ((void __iomem *)(map)->handle) + (offset))
  25 /** Write a dword into a MMIO region */
  26 #define DRM_WRITE32(map, offset, val)   writel(val, ((void __iomem *)(map)->handle) + (offset))
  27
  28 /** Read a qword from a MMIO region - be careful using these unless you really understand them */
  29 #define DRM_READ64(map, offset)         readq(((void __iomem *)(map)->handle) + (offset))
  30 /** Write a qword into a MMIO region */
  31 #define DRM_WRITE64(map, offset, val)   writeq(val, ((void __iomem *)(map)->handle) + (offset))
  32
  33 #define DRM_WAIT_ON( ret, queue, timeout, condition )           \
  34 do {                                                            \
  35         DECLARE_WAITQUEUE(entry, current);                      \
  36         unsigned long end = jiffies + (timeout);                \
  37         add_wait_queue(&(queue), &entry);                       \
  38                                                                 \
  39         for (;;) {                                              \
  40                 __set_current_state(TASK_INTERRUPTIBLE);        \
  41                 if (condition)                                  \
  42                         break;                                  \
  43                 if (time_after_eq(jiffies, end)) {              \
  44                         ret = -EBUSY;                           \
  45                         break;                                  \
  46                 }                                               \
  47                 schedule_timeout((HZ/100 > 1) ? HZ/100 : 1);    \
  48                 if (signal_pending(current)) {                  \
  49                         ret = -EINTR;                           \
  50                         break;                                  \
  51                 }                                               \
  52         }                                                       \
  53         __set_current_state(TASK_RUNNING);                      \
  54         remove_wait_queue(&(queue), &entry);                    \
  55 } while (0)