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 )		\
34do {								\
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)