Commit c43c5a88 authored by Jani Nikula's avatar Jani Nikula
Browse files

drm/i915/params: add i915 parameters to debugfs 



Add a debugfs subdirectory i915_params with all the i915 module
parameters. This is a first step, with lots of boilerplate, and not much
benefit yet.

This will result in a new device specific debugfs directory at
/sys/kernel/debug/dri/<N>/i915_params duplicating the module specific
sysfs directory at /sys/module/i915/parameters/. Going forward, all
users of the parameters should use the debugfs, with the module
parameters being phased out.

Add debugfs permissions to I915_PARAMS_FOR_EACH(). This duplicates the
mode with module parameter sysfs, but the goal is to make the module
parameters read-only initial values for device specific parameters.

0 mode will bypass debugfs creation. Use it for verbose_state_checks
which will need special attention in follow-up work.

Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/600101c8433e7caf9303663fc85a9972fa1f05e7.1575560168.git.jani.nikula@intel.com
parent f22fd334

drivers/gpu/drm/i915/Makefile

+4 −1
Original line number Diff line number Diff line
@@ -66,7 +66,10 @@ i915-y += \ 
	i915_user_extensions.o



i915-$(CONFIG_COMPAT)   += i915_ioc32.o

i915-$(CONFIG_DEBUG_FS) += i915_debugfs.o display/intel_pipe_crc.o

i915-$(CONFIG_DEBUG_FS) += \

	i915_debugfs.o \

	i915_debugfs_params.o \

	display/intel_pipe_crc.o

i915-$(CONFIG_PERF_EVENTS) += i915_pmu.o



# "Graphics Technology" (aka we talk to the gpu)

drivers/gpu/drm/i915/i915_debugfs.c

+3 −1
Original line number Diff line number Diff line
@@ -48,6 +48,7 @@ 
#include "gt/uc/intel_guc_submission.h"



#include "i915_debugfs.h"

#include "i915_debugfs_params.h"

#include "i915_irq.h"

#include "i915_trace.h"

#include "intel_csr.h"
@@ -4311,9 +4312,10 @@ int i915_debugfs_register(struct drm_i915_private *dev_priv) 
	struct drm_minor *minor = dev_priv->drm.primary;

	int i;



	i915_debugfs_params(dev_priv);



	debugfs_create_file("i915_forcewake_user", S_IRUSR, minor->debugfs_root,

			    to_i915(minor->dev), &i915_forcewake_fops);



	for (i = 0; i < ARRAY_SIZE(i915_debugfs_files); i++) {

		debugfs_create_file(i915_debugfs_files[i].name,

				    S_IRUGO | S_IWUSR,

drivers/gpu/drm/i915/i915_debugfs_params.c

0 → 100644
+233 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: MIT

/*

 * Copyright © 2019 Intel Corporation

 */



#include <linux/kernel.h>



#include "i915_drv.h"

#include "i915_params.h"



/* int param */

static int i915_param_int_show(struct seq_file *m, void *data)

{

	int *value = m->private;



	seq_printf(m, "%d\n", *value);



	return 0;

}



static int i915_param_int_open(struct inode *inode, struct file *file)

{

	return single_open(file, i915_param_int_show, inode->i_private);

}



static ssize_t i915_param_int_write(struct file *file,

				    const char __user *ubuf, size_t len,

				    loff_t *offp)

{

	struct seq_file *m = file->private_data;

	int *value = m->private;

	int ret;



	ret = kstrtoint_from_user(ubuf, len, 0, value);



	return ret ?: len;

}



static const struct file_operations i915_param_int_fops = {

	.owner = THIS_MODULE,

	.open = i915_param_int_open,

	.read = seq_read,

	.write = i915_param_int_write,

	.llseek = default_llseek,

	.release = single_release,

};



static const struct file_operations i915_param_int_fops_ro = {

	.owner = THIS_MODULE,

	.open = i915_param_int_open,

	.read = seq_read,

	.llseek = default_llseek,

	.release = single_release,

};



/* unsigned int param */

static int i915_param_uint_show(struct seq_file *m, void *data)

{

	unsigned int *value = m->private;



	seq_printf(m, "%u\n", *value);



	return 0;

}



static int i915_param_uint_open(struct inode *inode, struct file *file)

{

	return single_open(file, i915_param_uint_show, inode->i_private);

}



static ssize_t i915_param_uint_write(struct file *file,

				     const char __user *ubuf, size_t len,

				     loff_t *offp)

{

	struct seq_file *m = file->private_data;

	unsigned int *value = m->private;

	int ret;



	ret = kstrtouint_from_user(ubuf, len, 0, value);



	return ret ?: len;

}



static const struct file_operations i915_param_uint_fops = {

	.owner = THIS_MODULE,

	.open = i915_param_uint_open,

	.read = seq_read,

	.write = i915_param_uint_write,

	.llseek = default_llseek,

	.release = single_release,

};



static const struct file_operations i915_param_uint_fops_ro = {

	.owner = THIS_MODULE,

	.open = i915_param_uint_open,

	.read = seq_read,

	.llseek = default_llseek,

	.release = single_release,

};



/* char * param */

static int i915_param_charp_show(struct seq_file *m, void *data)

{

	const char **s = m->private;



	seq_printf(m, "%s\n", *s);



	return 0;

}



static int i915_param_charp_open(struct inode *inode, struct file *file)

{

	return single_open(file, i915_param_charp_show, inode->i_private);

}



static ssize_t i915_param_charp_write(struct file *file,

				      const char __user *ubuf, size_t len,

				      loff_t *offp)

{

	struct seq_file *m = file->private_data;

	char **s = m->private;

	char *new, *old;



	/* FIXME: remove locking after params aren't the module params */

	kernel_param_lock(THIS_MODULE);



	old = *s;

	new = strndup_user(ubuf, PAGE_SIZE);

	if (IS_ERR(new)) {

		len = PTR_ERR(new);

		goto out;

	}



	*s = new;



	kfree(old);

out:

	kernel_param_unlock(THIS_MODULE);



	return len;

}



static const struct file_operations i915_param_charp_fops = {

	.owner = THIS_MODULE,

	.open = i915_param_charp_open,

	.read = seq_read,

	.write = i915_param_charp_write,

	.llseek = default_llseek,

	.release = single_release,

};



static const struct file_operations i915_param_charp_fops_ro = {

	.owner = THIS_MODULE,

	.open = i915_param_charp_open,

	.read = seq_read,

	.llseek = default_llseek,

	.release = single_release,

};



#define RO(mode) (((mode) & 0222) == 0)



static struct dentry *

i915_debugfs_create_int(const char *name, umode_t mode,

			struct dentry *parent, int *value)

{

	return debugfs_create_file_unsafe(name, mode, parent, value,

					  RO(mode) ? &i915_param_int_fops_ro :

					  &i915_param_int_fops);

}



static struct dentry *

i915_debugfs_create_uint(const char *name, umode_t mode,

			 struct dentry *parent, unsigned int *value)

{

	return debugfs_create_file_unsafe(name, mode, parent, value,

					  RO(mode) ? &i915_param_uint_fops_ro :

					  &i915_param_uint_fops);

}



static struct dentry *

i915_debugfs_create_charp(const char *name, umode_t mode,

			  struct dentry *parent, char **value)

{

	return debugfs_create_file(name, mode, parent, value,

				   RO(mode) ? &i915_param_charp_fops_ro :

				   &i915_param_charp_fops);

}



static __always_inline void

_i915_param_create_file(struct dentry *parent, const char *name,

			const char *type, int mode, void *value)

{

	if (!mode)

		return;



	if (!__builtin_strcmp(type, "bool"))

		debugfs_create_bool(name, mode, parent, value);

	else if (!__builtin_strcmp(type, "int"))

		i915_debugfs_create_int(name, mode, parent, value);

	else if (!__builtin_strcmp(type, "unsigned int"))

		i915_debugfs_create_uint(name, mode, parent, value);

	else if (!__builtin_strcmp(type, "unsigned long"))

		debugfs_create_ulong(name, mode, parent, value);

	else if (!__builtin_strcmp(type, "char *"))

		i915_debugfs_create_charp(name, mode, parent, value);

	else

		WARN(1, "no debugfs fops defined for param type %s (i915.%s)\n",

		     type, name);

}



/* add a subdirectory with files for each i915 param */

struct dentry *i915_debugfs_params(struct drm_i915_private *i915)

{

	struct drm_minor *minor = i915->drm.primary;

	struct i915_params *params = &i915_modparams;

	struct dentry *dir;



	dir = debugfs_create_dir("i915_params", minor->debugfs_root);

	if (IS_ERR(dir))

		return dir;



	/*

	 * Note: We could create files for params needing special handling

	 * here. Set mode in params to 0 to skip the generic create file, or

	 * just let the generic create file fail silently with -EEXIST.

	 */



#define REGISTER(T, x, unused, mode, ...) _i915_param_create_file(dir, #x, #T, mode, &params->x);

	I915_PARAMS_FOR_EACH(REGISTER);

#undef REGISTER



	return dir;

}

drivers/gpu/drm/i915/i915_debugfs_params.h

0 → 100644
+14 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: MIT */

/*

 * Copyright © 2019 Intel Corporation

 */



#ifndef __I915_DEBUGFS_PARAMS__

#define __I915_DEBUGFS_PARAMS__



struct dentry;

struct drm_i915_private;



struct dentry *i915_debugfs_params(struct drm_i915_private *i915);



#endif /* __I915_DEBUGFS_PARAMS__ */

drivers/gpu/drm/i915/i915_params.c

+1 −1
Original line number Diff line number Diff line
@@ -35,7 +35,7 @@ 
	MODULE_PARM_DESC(name, desc)



struct i915_params i915_modparams __read_mostly = {

#define MEMBER(T, member, value) .member = (value),

#define MEMBER(T, member, value, ...) .member = (value),

	I915_PARAMS_FOR_EACH(MEMBER)

#undef MEMBER

};

CRA Git | Maintained and supported by SUSTech CRA and CCSE