drivers/gpu/drm/drm_print.c - third_party/linux - Git at Google

 /*
  * Copyright (C) 2016 Red Hat
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  * OTHER DEALINGS IN THE SOFTWARE.
  *
  * Authors:
  * Rob Clark <robdclark@gmail.com>
  */

 #define DEBUG /* for pr_debug() */

 #include <stdarg.h>

 #include <linux/io.h>
 #include <linux/moduleparam.h>
 #include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/trace.h>

 #include <drm/drm.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_print.h>

 /*
  * __drm_debug_syslog: Enable debug output to system logs
  * Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
  */
 unsigned int __drm_debug_syslog;
 EXPORT_SYMBOL(__drm_debug_syslog);

 /*
  * __drm_debug_trace: Enable debug output in drm tracing instance.
  * Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
  */
 unsigned int __drm_debug_trace;
 EXPORT_SYMBOL(__drm_debug_trace);

 #define DEBUG_PARM_DESC(dst) \
 "Enable debug output to " dst ", where each bit enables a debug category.\n" \
 "\t\tBit 0 (0x01)  will enable CORE messages (drm core code)\n" \
 "\t\tBit 1 (0x02)  will enable DRIVER messages (drm controller code)\n" \
 "\t\tBit 2 (0x04)  will enable KMS messages (modesetting code)\n" \
 "\t\tBit 3 (0x08)  will enable PRIME messages (prime code)\n" \
 "\t\tBit 4 (0x10)  will enable ATOMIC messages (atomic code)\n" \
 "\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n" \
 "\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n" \
 "\t\tBit 8 (0x100) will enable DP messages (displayport code)"

 MODULE_PARM_DESC(debug, DEBUG_PARM_DESC("syslog"));
 module_param_named(debug, __drm_debug_syslog, int, 0600);

 MODULE_PARM_DESC(trace, DEBUG_PARM_DESC("tracefs"));
 module_param_named(trace, __drm_debug_trace, int, 0600);

 #ifdef CONFIG_TRACING
 struct trace_array *trace_arr;
 #endif

 void __drm_puts_coredump(struct drm_printer *p, const char *str)
 {
 	struct drm_print_iterator *iterator = p->arg;
 	ssize_t len;

 	if (!iterator->remain)
 		return;

 	if (iterator->offset < iterator->start) {
 		ssize_t copy;

 		len = strlen(str);

 		if (iterator->offset + len <= iterator->start) {
 			iterator->offset += len;
 			return;
 		}

 		copy = len - (iterator->start - iterator->offset);

 		if (copy > iterator->remain)
 			copy = iterator->remain;

 		/* Copy out the bit of the string that we need */
 		memcpy(iterator->data,
 			str + (iterator->start - iterator->offset), copy);

 		iterator->offset = iterator->start + copy;
 		iterator->remain -= copy;
 	} else {
 		ssize_t pos = iterator->offset - iterator->start;

 		len = min_t(ssize_t, strlen(str), iterator->remain);

 		memcpy(iterator->data + pos, str, len);

 		iterator->offset += len;
 		iterator->remain -= len;
 	}
 }
 EXPORT_SYMBOL(__drm_puts_coredump);

 void __drm_printfn_coredump(struct drm_printer *p, struct va_format *vaf)
 {
 	struct drm_print_iterator *iterator = p->arg;
 	size_t len;
 	char *buf;

 	if (!iterator->remain)
 		return;

 	/* Figure out how big the string will be */
 	len = snprintf(NULL, 0, "%pV", vaf);

 	/* This is the easiest path, we've already advanced beyond the offset */
 	if (iterator->offset + len <= iterator->start) {
 		iterator->offset += len;
 		return;
 	}

 	/* Then check if we can directly copy into the target buffer */
 	if ((iterator->offset >= iterator->start) && (len < iterator->remain)) {
 		ssize_t pos = iterator->offset - iterator->start;

 		snprintf(((char *) iterator->data) + pos,
 			iterator->remain, "%pV", vaf);

 		iterator->offset += len;
 		iterator->remain -= len;

 		return;
 	}

 	/*
 	 * Finally, hit the slow path and make a temporary string to copy over
 	 * using _drm_puts_coredump
 	 */
 	buf = kmalloc(len + 1, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
 	if (!buf)
 		return;

 	snprintf(buf, len + 1, "%pV", vaf);
 	__drm_puts_coredump(p, (const char *) buf);

 	kfree(buf);
 }
 EXPORT_SYMBOL(__drm_printfn_coredump);

 void __drm_puts_seq_file(struct drm_printer *p, const char *str)
 {
 	seq_puts(p->arg, str);
 }
 EXPORT_SYMBOL(__drm_puts_seq_file);

 void __drm_printfn_seq_file(struct drm_printer *p, struct va_format *vaf)
 {
 	seq_printf(p->arg, "%pV", vaf);
 }
 EXPORT_SYMBOL(__drm_printfn_seq_file);

 void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf)
 {
 	dev_info(p->arg, "[" DRM_NAME "] %pV", vaf);
 }
 EXPORT_SYMBOL(__drm_printfn_info);

 void __drm_printfn_debug_syslog(struct drm_printer *p, struct va_format *vaf)
 {
 	pr_debug("%s %pV", p->prefix, vaf);
 }
 EXPORT_SYMBOL(__drm_printfn_debug_syslog);

 void __drm_printfn_trace(struct drm_printer *p, struct va_format *vaf)
 {
 	drm_trace_printf("%s %pV", p->prefix, vaf);
 }
 EXPORT_SYMBOL(__drm_printfn_trace);

 void __drm_printfn_debug_syslog_and_trace(struct drm_printer *p,
 					   struct va_format *vaf)
 {
 	pr_debug("%s %pV", p->prefix, vaf);
 	drm_trace_printf("%s %pV", p->prefix, vaf);
 }
 EXPORT_SYMBOL(__drm_printfn_debug_syslog_and_trace);

 void __drm_printfn_err(struct drm_printer *p, struct va_format *vaf)
 {
 	pr_err("*ERROR* %s %pV", p->prefix, vaf);
 }
 EXPORT_SYMBOL(__drm_printfn_err);

 void __drm_printfn_noop(struct drm_printer *p, struct va_format *vaf)
 {
 }
 EXPORT_SYMBOL(__drm_printfn_noop);

 /**
  * drm_puts - print a const string to a &drm_printer stream
  * @p: the &drm printer
  * @str: const string
  *
  * Allow &drm_printer types that have a constant string
  * option to use it.
  */
 void drm_puts(struct drm_printer *p, const char *str)
 {
 	if (p->puts)
 		p->puts(p, str);
 	else
 		drm_printf(p, "%s", str);
 }
 EXPORT_SYMBOL(drm_puts);

 /**
  * drm_printf - print to a &drm_printer stream
  * @p: the &drm_printer
  * @f: format string
  */
 void drm_printf(struct drm_printer *p, const char *f, ...)
 {
 	va_list args;

 	va_start(args, f);
 	drm_vprintf(p, f, &args);
 	va_end(args);
 }
 EXPORT_SYMBOL(drm_printf);

 void drm_dev_printk(const struct device *dev, const char *level,
 		    const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;

 	va_start(args, format);
 	vaf.fmt = format;
 	vaf.va = &args;
 	drm_trace_printf("%s%s[" DRM_NAME ":%ps] %pV",
 			 dev ? dev_name(dev) : "", dev ? " " : "",
 			 __builtin_return_address(0), &vaf);
 	va_end(args);

 	va_start(args, format);
 	vaf.fmt = format;
 	vaf.va = &args;

 	if (dev)
 		dev_printk(level, dev, "[" DRM_NAME ":%ps] %pV",
 			   __builtin_return_address(0), &vaf);
 	else
 		printk("%s" "[" DRM_NAME ":%ps] %pV",
 		       level, __builtin_return_address(0), &vaf);

 	va_end(args);
 }
 EXPORT_SYMBOL(drm_dev_printk);

 void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
 		 const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;

 	if (drm_debug_syslog_enabled(category)) {
 		va_start(args, format);
 		vaf.fmt = format;
 		vaf.va = &args;

 		if (dev)
 			dev_printk(KERN_DEBUG, dev, "[" DRM_NAME ":%ps] %pV",
 				__builtin_return_address(0), &vaf);
 		else
 			printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
 			__builtin_return_address(0), &vaf);

 		va_end(args);
 	}

 	if (drm_debug_trace_enabled(category)) {
 		va_start(args, format);
 		vaf.fmt = format;
 		vaf.va = &args;
 		drm_trace_printf("%s%s[" DRM_NAME ":%ps] %pV",
 				 dev ? dev_name(dev) : "", dev ? " " : "",
 				 __builtin_return_address(0), &vaf);
 		va_end(args);
 	}
 }
 EXPORT_SYMBOL(drm_dev_dbg);

 void __drm_dbg(enum drm_debug_category category, const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;

 	if (drm_debug_syslog_enabled(category)) {
 		va_start(args, format);
 		vaf.fmt = format;
 		vaf.va = &args;

 		printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
 		__builtin_return_address(0), &vaf);

 		va_end(args);
 	}

 	if (drm_debug_trace_enabled(category)) {
 		va_start(args, format);
 		vaf.fmt = format;
 		vaf.va = &args;
 		drm_trace_printf("[" DRM_NAME ":%ps] %pV",
 				 __builtin_return_address(0), &vaf);
 		va_end(args);
 	}
 }
 EXPORT_SYMBOL(__drm_dbg);

 void __drm_err(const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;

 	va_start(args, format);
 	vaf.fmt = format;
 	vaf.va = &args;

 	printk(KERN_ERR "[" DRM_NAME ":%ps] *ERROR* %pV",
 	       __builtin_return_address(0), &vaf);

 	va_end(args);
 }
 EXPORT_SYMBOL(__drm_err);

 /**
  * drm_print_regset32 - print the contents of registers to a
  * &drm_printer stream.
  *
  * @p: the &drm printer
  * @regset: the list of registers to print.
  *
  * Often in driver debug, it's useful to be able to either capture the
  * contents of registers in the steady state using debugfs or at
  * specific points during operation.  This lets the driver have a
  * single list of registers for both.
  */
 void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset)
 {
 	int namelen = 0;
 	int i;

 	for (i = 0; i < regset->nregs; i++)
 		namelen = max(namelen, (int)strlen(regset->regs[i].name));

 	for (i = 0; i < regset->nregs; i++) {
 		drm_printf(p, "%*s = 0x%08x\n",
 			   namelen, regset->regs[i].name,
 			   readl(regset->base + regset->regs[i].offset));
 	}
 }
 EXPORT_SYMBOL(drm_print_regset32);


 /**
  * DOC: DRM Tracing
  *
  * *tl;dr* DRM tracing is a lightweight alternative to traditional DRM debug
  * logging.
  *
  * While DRM logging is quite convenient when reproducing a specific issue, it
  * doesn't help when something goes wrong unexpectedly. There are a couple
  * reasons why one does not want to enable DRM logging at all times:
  *
  * 1. We don't want to overwhelm syslog with drm spam, others have to use it too
  * 2. Console logging is slow
  *
  * DRM tracing aims to solve both these problems.
  *
  * To use DRM tracing, set the drm.trace module parameter (via cmdline or sysfs)
  * to a DRM debug category mask (this is a bitmask of &drm_debug_category
  * values):
  * ::
  *
  *    eg: echo 0x106 > /sys/module/drm/parameters/trace
  *
  * Once active, all log messages in the specified categories will be written to
  * the DRM trace. Once at capacity, the trace will overwrite old messages with
  * new ones. At any point, one can read the trace file to extract the previous N
  * DRM messages:
  * ::
  *
  *    eg: cat /sys/kernel/tracing/instances/drm/trace
  *
  * Considerations
  * **************
  * The trace is subsystem wide, so if you have multiple devices active, they
  * will be adding logs to the same trace.
  *
  * The contents of the DRM Trace are **not** considered UABI. **DO NOT depend on
  * the values of these traces in your userspace.** These traces are intended for
  * entertainment purposes only. The contents of these logs carry no warranty,
  * expressed or implied.
  */


 #ifdef CONFIG_TRACING

 /**
  * drm_trace_init - initializes the drm trace array
  *
  * This function fetches (or creates) the drm trace array. This should be called
  * once on drm subsystem creation and matched with drm_trace_cleanup().
  */
 void drm_trace_init(void)
 {
 	int ret;

 	trace_arr = trace_array_get_by_name("drm", "");
 	if (!trace_arr)
 		return;

 	ret = trace_array_init_printk(trace_arr);
 	if (ret)
 		drm_trace_cleanup();
 }
 EXPORT_SYMBOL(drm_trace_init);

 /**
  * drm_trace_printf - adds an entry to the drm tracefs instance
  * @format: printf format of the message to add to the trace
  *
  * This function adds a new entry in the drm tracefs instance
  */
 void drm_trace_printf(const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;

 	if (!trace_arr)
 		return;

 	va_start(args, format);
 	vaf.fmt = format;
 	vaf.va = &args;
 	trace_array_printk(trace_arr, _THIS_IP_, "%pV", &vaf);
 	va_end(args);
 }

 /**
  * drm_trace_cleanup - destroys the drm trace array
  *
  * This function destroys the drm trace array created with drm_trace_init. This
  * should be called once on drm subsystem close and matched with
  * drm_trace_init().
  */
 void drm_trace_cleanup(void)
 {
 	if (trace_arr) {
 		trace_array_put(trace_arr);
 		trace_array_destroy(trace_arr);
 		trace_arr = NULL;
 	}
 }
 EXPORT_SYMBOL(drm_trace_cleanup);
 #endif
	/*
	* Copyright (C) 2016 Red Hat
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	* and/or sell copies of the Software, and to permit persons to whom the
	* Software is furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
	* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
	* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
	* OTHER DEALINGS IN THE SOFTWARE.
	*
	* Authors:
	* Rob Clark <robdclark@gmail.com>
	*/

	#define DEBUG /* for pr_debug() */

	#include <stdarg.h>

	#include <linux/io.h>
	#include <linux/moduleparam.h>
	#include <linux/seq_file.h>
	#include <linux/slab.h>
	#include <linux/trace.h>

	#include <drm/drm.h>
	#include <drm/drm_drv.h>
	#include <drm/drm_print.h>

	/*
	* __drm_debug_syslog: Enable debug output to system logs
	* Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
	*/
	unsigned int __drm_debug_syslog;
	EXPORT_SYMBOL(__drm_debug_syslog);

	/*
	* __drm_debug_trace: Enable debug output in drm tracing instance.
	* Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
	*/
	unsigned int __drm_debug_trace;
	EXPORT_SYMBOL(__drm_debug_trace);

	#define DEBUG_PARM_DESC(dst) \
	"Enable debug output to " dst ", where each bit enables a debug category.\n" \
	"\t\tBit 0 (0x01) will enable CORE messages (drm core code)\n" \
	"\t\tBit 1 (0x02) will enable DRIVER messages (drm controller code)\n" \
	"\t\tBit 2 (0x04) will enable KMS messages (modesetting code)\n" \
	"\t\tBit 3 (0x08) will enable PRIME messages (prime code)\n" \
	"\t\tBit 4 (0x10) will enable ATOMIC messages (atomic code)\n" \
	"\t\tBit 5 (0x20) will enable VBL messages (vblank code)\n" \
	"\t\tBit 7 (0x80) will enable LEASE messages (leasing code)\n" \
	"\t\tBit 8 (0x100) will enable DP messages (displayport code)"

	MODULE_PARM_DESC(debug, DEBUG_PARM_DESC("syslog"));
	module_param_named(debug, __drm_debug_syslog, int, 0600);

	MODULE_PARM_DESC(trace, DEBUG_PARM_DESC("tracefs"));
	module_param_named(trace, __drm_debug_trace, int, 0600);

	#ifdef CONFIG_TRACING
	struct trace_array *trace_arr;
	#endif

	void __drm_puts_coredump(struct drm_printer p, const char str)
	{
	struct drm_print_iterator *iterator = p->arg;
	ssize_t len;

	if (!iterator->remain)
	return;

	if (iterator->offset < iterator->start) {
	ssize_t copy;

	len = strlen(str);

	if (iterator->offset + len <= iterator->start) {
	iterator->offset += len;
	return;
	}

	copy = len - (iterator->start - iterator->offset);

	if (copy > iterator->remain)
	copy = iterator->remain;

	/* Copy out the bit of the string that we need */
	memcpy(iterator->data,
	str + (iterator->start - iterator->offset), copy);

	iterator->offset = iterator->start + copy;
	iterator->remain -= copy;
	} else {
	ssize_t pos = iterator->offset - iterator->start;

	len = min_t(ssize_t, strlen(str), iterator->remain);

	memcpy(iterator->data + pos, str, len);

	iterator->offset += len;
	iterator->remain -= len;
	}
	}
	EXPORT_SYMBOL(__drm_puts_coredump);

	void __drm_printfn_coredump(struct drm_printer p, struct va_format vaf)
	{
	struct drm_print_iterator *iterator = p->arg;
	size_t len;
	char *buf;

	if (!iterator->remain)
	return;

	/* Figure out how big the string will be */
	len = snprintf(NULL, 0, "%pV", vaf);

	/* This is the easiest path, we've already advanced beyond the offset */
	if (iterator->offset + len <= iterator->start) {
	iterator->offset += len;
	return;
	}

	/* Then check if we can directly copy into the target buffer */
	if ((iterator->offset >= iterator->start) && (len < iterator->remain)) {
	ssize_t pos = iterator->offset - iterator->start;

	snprintf(((char *) iterator->data) + pos,
	iterator->remain, "%pV", vaf);

	iterator->offset += len;
	iterator->remain -= len;

	return;
	}

	/*
	* Finally, hit the slow path and make a temporary string to copy over
	* using _drm_puts_coredump
	*/
	buf = kmalloc(len + 1, GFP_KERNEL \| __GFP_NOWARN \| __GFP_NORETRY);
	if (!buf)
	return;

	snprintf(buf, len + 1, "%pV", vaf);
	__drm_puts_coredump(p, (const char *) buf);

	kfree(buf);
	}
	EXPORT_SYMBOL(__drm_printfn_coredump);

	void __drm_puts_seq_file(struct drm_printer p, const char str)
	{
	seq_puts(p->arg, str);
	}
	EXPORT_SYMBOL(__drm_puts_seq_file);

	void __drm_printfn_seq_file(struct drm_printer p, struct va_format vaf)
	{
	seq_printf(p->arg, "%pV", vaf);
	}
	EXPORT_SYMBOL(__drm_printfn_seq_file);

	void __drm_printfn_info(struct drm_printer p, struct va_format vaf)
	{
	dev_info(p->arg, "[" DRM_NAME "] %pV", vaf);
	}
	EXPORT_SYMBOL(__drm_printfn_info);

	void __drm_printfn_debug_syslog(struct drm_printer p, struct va_format vaf)
	{
	pr_debug("%s %pV", p->prefix, vaf);
	}
	EXPORT_SYMBOL(__drm_printfn_debug_syslog);

	void __drm_printfn_trace(struct drm_printer p, struct va_format vaf)
	{
	drm_trace_printf("%s %pV", p->prefix, vaf);
	}
	EXPORT_SYMBOL(__drm_printfn_trace);

	void __drm_printfn_debug_syslog_and_trace(struct drm_printer *p,
	struct va_format *vaf)
	{
	pr_debug("%s %pV", p->prefix, vaf);
	drm_trace_printf("%s %pV", p->prefix, vaf);
	}
	EXPORT_SYMBOL(__drm_printfn_debug_syslog_and_trace);

	void __drm_printfn_err(struct drm_printer p, struct va_format vaf)
	{
	pr_err("ERROR %s %pV", p->prefix, vaf);
	}
	EXPORT_SYMBOL(__drm_printfn_err);

	void __drm_printfn_noop(struct drm_printer p, struct va_format vaf)
	{
	}
	EXPORT_SYMBOL(__drm_printfn_noop);

	/**
	* drm_puts - print a const string to a &drm_printer stream
	* @p: the &drm printer
	* @str: const string
	*
	* Allow &drm_printer types that have a constant string
	* option to use it.
	*/
	void drm_puts(struct drm_printer p, const char str)
	{
	if (p->puts)
	p->puts(p, str);
	else
	drm_printf(p, "%s", str);
	}
	EXPORT_SYMBOL(drm_puts);

	/**
	* drm_printf - print to a &drm_printer stream
	* @p: the &drm_printer
	* @f: format string
	*/
	void drm_printf(struct drm_printer p, const char f, ...)
	{
	va_list args;

	va_start(args, f);
	drm_vprintf(p, f, &args);
	va_end(args);
	}
	EXPORT_SYMBOL(drm_printf);

	void drm_dev_printk(const struct device dev, const char level,
	const char *format, ...)
	{
	struct va_format vaf;
	va_list args;

	va_start(args, format);
	vaf.fmt = format;
	vaf.va = &args;
	drm_trace_printf("%s%s[" DRM_NAME ":%ps] %pV",
	dev ? dev_name(dev) : "", dev ? " " : "",
	__builtin_return_address(0), &vaf);
	va_end(args);

	va_start(args, format);
	vaf.fmt = format;
	vaf.va = &args;

	if (dev)
	dev_printk(level, dev, "[" DRM_NAME ":%ps] %pV",
	__builtin_return_address(0), &vaf);
	else
	printk("%s" "[" DRM_NAME ":%ps] %pV",
	level, __builtin_return_address(0), &vaf);

	va_end(args);
	}
	EXPORT_SYMBOL(drm_dev_printk);

	void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
	const char *format, ...)
	{
	struct va_format vaf;
	va_list args;

	if (drm_debug_syslog_enabled(category)) {
	va_start(args, format);
	vaf.fmt = format;
	vaf.va = &args;

	if (dev)
	dev_printk(KERN_DEBUG, dev, "[" DRM_NAME ":%ps] %pV",
	__builtin_return_address(0), &vaf);
	else
	printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
	__builtin_return_address(0), &vaf);

	va_end(args);
	}

	if (drm_debug_trace_enabled(category)) {
	va_start(args, format);
	vaf.fmt = format;
	vaf.va = &args;
	drm_trace_printf("%s%s[" DRM_NAME ":%ps] %pV",
	dev ? dev_name(dev) : "", dev ? " " : "",
	__builtin_return_address(0), &vaf);
	va_end(args);
	}
	}
	EXPORT_SYMBOL(drm_dev_dbg);

	void __drm_dbg(enum drm_debug_category category, const char *format, ...)
	{
	struct va_format vaf;
	va_list args;

	if (drm_debug_syslog_enabled(category)) {
	va_start(args, format);
	vaf.fmt = format;
	vaf.va = &args;

	printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
	__builtin_return_address(0), &vaf);

	va_end(args);
	}

	if (drm_debug_trace_enabled(category)) {
	va_start(args, format);
	vaf.fmt = format;
	vaf.va = &args;
	drm_trace_printf("[" DRM_NAME ":%ps] %pV",
	__builtin_return_address(0), &vaf);
	va_end(args);
	}
	}
	EXPORT_SYMBOL(__drm_dbg);

	void __drm_err(const char *format, ...)
	{
	struct va_format vaf;
	va_list args;

	va_start(args, format);
	vaf.fmt = format;
	vaf.va = &args;

	printk(KERN_ERR "[" DRM_NAME ":%ps] ERROR %pV",
	__builtin_return_address(0), &vaf);

	va_end(args);
	}
	EXPORT_SYMBOL(__drm_err);

	/**
	* drm_print_regset32 - print the contents of registers to a
	* &drm_printer stream.
	*
	* @p: the &drm printer
	* @regset: the list of registers to print.
	*
	* Often in driver debug, it's useful to be able to either capture the
	* contents of registers in the steady state using debugfs or at
	* specific points during operation. This lets the driver have a
	* single list of registers for both.
	*/
	void drm_print_regset32(struct drm_printer p, struct debugfs_regset32 regset)
	{
	int namelen = 0;
	int i;

	for (i = 0; i < regset->nregs; i++)
	namelen = max(namelen, (int)strlen(regset->regs[i].name));

	for (i = 0; i < regset->nregs; i++) {
	drm_printf(p, "%*s = 0x%08x\n",
	namelen, regset->regs[i].name,
	readl(regset->base + regset->regs[i].offset));
	}
	}
	EXPORT_SYMBOL(drm_print_regset32);


	/**
	* DOC: DRM Tracing
	*
	* tl;dr DRM tracing is a lightweight alternative to traditional DRM debug
	* logging.
	*
	* While DRM logging is quite convenient when reproducing a specific issue, it
	* doesn't help when something goes wrong unexpectedly. There are a couple
	* reasons why one does not want to enable DRM logging at all times:
	*
	* 1. We don't want to overwhelm syslog with drm spam, others have to use it too
	* 2. Console logging is slow
	*
	* DRM tracing aims to solve both these problems.
	*
	* To use DRM tracing, set the drm.trace module parameter (via cmdline or sysfs)
	* to a DRM debug category mask (this is a bitmask of &drm_debug_category
	* values):
	* ::
	*
	* eg: echo 0x106 > /sys/module/drm/parameters/trace
	*
	* Once active, all log messages in the specified categories will be written to
	* the DRM trace. Once at capacity, the trace will overwrite old messages with
	* new ones. At any point, one can read the trace file to extract the previous N
	* DRM messages:
	* ::
	*
	* eg: cat /sys/kernel/tracing/instances/drm/trace
	*
	* Considerations
	* **************
	* The trace is subsystem wide, so if you have multiple devices active, they
	* will be adding logs to the same trace.
	*
	* The contents of the DRM Trace are not considered UABI. **DO NOT depend on
	* the values of these traces in your userspace.** These traces are intended for
	* entertainment purposes only. The contents of these logs carry no warranty,
	* expressed or implied.
	*/


	#ifdef CONFIG_TRACING

	/**
	* drm_trace_init - initializes the drm trace array
	*
	* This function fetches (or creates) the drm trace array. This should be called
	* once on drm subsystem creation and matched with drm_trace_cleanup().
	*/
	void drm_trace_init(void)
	{
	int ret;

	trace_arr = trace_array_get_by_name("drm", "");
	if (!trace_arr)
	return;

	ret = trace_array_init_printk(trace_arr);
	if (ret)
	drm_trace_cleanup();
	}
	EXPORT_SYMBOL(drm_trace_init);

	/**
	* drm_trace_printf - adds an entry to the drm tracefs instance
	* @format: printf format of the message to add to the trace
	*
	* This function adds a new entry in the drm tracefs instance
	*/
	void drm_trace_printf(const char *format, ...)
	{
	struct va_format vaf;
	va_list args;

	if (!trace_arr)
	return;

	va_start(args, format);
	vaf.fmt = format;
	vaf.va = &args;
	trace_array_printk(trace_arr, _THIS_IP_, "%pV", &vaf);
	va_end(args);
	}

	/**
	* drm_trace_cleanup - destroys the drm trace array
	*
	* This function destroys the drm trace array created with drm_trace_init. This
	* should be called once on drm subsystem close and matched with
	* drm_trace_init().
	*/
	void drm_trace_cleanup(void)
	{
	if (trace_arr) {
	trace_array_put(trace_arr);
	trace_array_destroy(trace_arr);
	trace_arr = NULL;
	}
	}
	EXPORT_SYMBOL(drm_trace_cleanup);
	#endif