linux/drivers/gpu/drm/drm_print.c
Eric Anholt 5f513cc89e drm: Add a helper function for printing a debugfs_regset32.
The debugfs_regset32 is nice to use for reducing boilerplate in
dumping a bunch of regs in debugfs, but we also want to be able to
print to dmesg them at runtime for driver debugging.  drm_printer lets
us format debugfs and the printk the same way.

v2: Add some kerneldoc for the function (requested by danvet)

Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190220210343.28157-1-eric@anholt.net
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com> (v1)
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2019-04-01 10:44:34 -07:00

284 lines
6.7 KiB
C

/*
* 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/seq_file.h>
#include <drm/drmP.h>
#include <drm/drm_print.h>
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(struct drm_printer *p, struct va_format *vaf)
{
pr_debug("%s %pV", p->prefix, vaf);
}
EXPORT_SYMBOL(__drm_printfn_debug);
/**
* 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;
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, unsigned int category,
const char *format, ...)
{
struct va_format vaf;
va_list args;
if (!(drm_debug & category))
return;
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);
}
EXPORT_SYMBOL(drm_dev_dbg);
void drm_dbg(unsigned int category, const char *format, ...)
{
struct va_format vaf;
va_list args;
if (!(drm_debug & category))
return;
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);
}
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);