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|
/*
* Copyright © 2013 Intel Corporation
*
* 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 (including the next
* paragraph) 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 AUTHORS OR COPYRIGHT HOLDERS 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.
*
*/
#include <inttypes.h>
#include <sys/stat.h>
#include <sys/mount.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <i915_drm.h>
#include "drmtest.h"
#include "igt_aux.h"
#include "igt_kms.h"
#include "igt_debugfs.h"
/**
* SECTION:igt_debugfs
* @short_description: Support code for debugfs features
* @title: debugfs
* @include: igt.h
*
* This library provides helpers to access debugfs features. On top of some
* basic functions to access debugfs files with e.g. igt_debugfs_open() it also
* provides higher-level wrappers for some debugfs features
*
* # Pipe CRC Support
*
* This library wraps up the kernel's support for capturing pipe CRCs into a
* neat and tidy package. For the detailed usage see all the functions which
* work on #igt_pipe_crc_t. This is supported on all platforms and outputs.
*
* Actually using pipe CRCs to write modeset tests is a bit tricky though, so
* there is no way to directly check a CRC: Both the details of the plane
* blending, color correction and other hardware and how exactly the CRC is
* computed at each tap point vary by hardware generation and are not disclosed.
*
* The only way to use #igt_crc_t CRCs therefore is to compare CRCs among each
* another either for equality or difference. Otherwise CRCs must be treated as
* completely opaque values. Note that not even CRCs from different pipes or tap
* points on the same platform can be compared. Hence only use
* igt_assert_crc_equal() to inspect CRC values captured by the same
* #igt_pipe_crc_t object.
*
* # Other debugfs interface wrappers
*
* This covers the miscellaneous debugfs interface wrappers:
*
* - drm/i915 supports interfaces to evict certain classes of gem buffer
* objects, see igt_drop_caches_set().
*
* - drm/i915 supports an interface to disable prefaulting, useful to test
* slow paths in ioctls. See igt_disable_prefault().
*/
/*
* General debugfs helpers
*/
typedef struct {
char root[128];
char dri_path[128];
} igt_debugfs_t;
static bool __igt_debugfs_init(igt_debugfs_t *debugfs)
{
const char *path = "/sys/kernel/debug";
struct stat st;
int n;
if (stat("/debug/dri", &st) == 0) {
path = "/debug/dri";
goto find_minor;
}
if (stat("/sys/kernel/debug/dri", &st) == 0)
goto find_minor;
igt_assert(stat("/sys/kernel/debug", &st) == 0);
mount("debug", "/sys/kernel/debug", "debugfs", 0, 0);
find_minor:
strcpy(debugfs->root, path);
for (n = 0; n < 16; n++) {
int len = sprintf(debugfs->dri_path, "%s/dri/%d", path, n);
sprintf(debugfs->dri_path + len, "/i915_error_state");
if (stat(debugfs->dri_path, &st) == 0) {
debugfs->dri_path[len] = '\0';
return true;
}
}
debugfs->dri_path[0] = '\0';
return false;
}
static igt_debugfs_t *__igt_debugfs_singleton(void)
{
static igt_debugfs_t singleton;
static bool init_done = false;
if (init_done)
return &singleton;
if (__igt_debugfs_init(&singleton)) {
init_done = true;
return &singleton;
} else {
return NULL;
}
}
/**
* igt_debugfs_open:
* @filename: name of the debugfs node to open
* @mode: mode bits as used by open()
*
* This opens a debugfs file as a Unix file descriptor. The filename should be
* relative to the drm device's root, i.e. without "drm/<minor>".
*
* Returns:
* The Unix file descriptor for the debugfs file or -1 if that didn't work out.
*/
int igt_debugfs_open(const char *filename, int mode)
{
char buf[1024];
igt_debugfs_t *debugfs = __igt_debugfs_singleton();
if (!debugfs)
return -1;
sprintf(buf, "%s/%s", debugfs->dri_path, filename);
return open(buf, mode);
}
/**
* igt_debugfs_fopen:
* @filename: name of the debugfs node to open
* @mode: mode string as used by fopen()
*
* This opens a debugfs file as a libc FILE. The filename should be
* relative to the drm device's root, i.e. without "drm/<minor>".
*
* Returns:
* The libc FILE pointer for the debugfs file or NULL if that didn't work out.
*/
FILE *igt_debugfs_fopen(const char *filename,
const char *mode)
{
char buf[1024];
igt_debugfs_t *debugfs = __igt_debugfs_singleton();
if (!debugfs)
return NULL;
sprintf(buf, "%s/%s", debugfs->dri_path, filename);
return fopen(buf, mode);
}
/**
* __igt_debugfs_read:
* @filename: file name
* @buf: buffer where the contents will be stored, allocated by the caller
* @buf_size: size of the buffer
*
* This function opens the debugfs file, reads it, stores the content in the
* provided buffer, then closes the file. Users should make sure that the buffer
* provided is big enough to fit the whole file, plus one byte.
*/
void __igt_debugfs_read(const char *filename, char *buf, int buf_size)
{
FILE *file;
size_t n_read;
file = igt_debugfs_fopen(filename, "r");
igt_assert(file);
n_read = fread(buf, 1, buf_size - 1, file);
igt_assert(n_read > 0);
igt_assert(feof(file));
buf[n_read] = '\0';
igt_assert(fclose(file) == 0);
}
/**
* igt_debugfs_search:
* @filename: file name
* @substring: string to search for in @filename
*
* Searches each line in @filename for the substring specified in @substring.
*
* Returns: True if the @substring is found to occur in @filename
*/
bool igt_debugfs_search(const char *filename, const char *substring)
{
FILE *file;
size_t n = 0;
char *line = NULL;
bool matched = false;
file = igt_debugfs_fopen(filename, O_RDONLY);
igt_assert(file);
while (getline(&line, &n, file) >= 0) {
matched = (strstr(line, substring) != NULL);
if (matched)
break;
}
free(line);
fclose(file);
return matched;
}
/*
* Pipe CRC
*/
/**
* igt_assert_crc_equal:
* @a: first pipe CRC value
* @b: second pipe CRC value
*
* Compares two CRC values and fails the testcase if they don't match with
* igt_fail(). Note that due to CRC collisions CRC based testcase can only
* assert that CRCs match, never that they are different. Otherwise there might
* be random testcase failures when different screen contents end up with the
* same CRC by chance.
*/
void igt_assert_crc_equal(igt_crc_t *a, igt_crc_t *b)
{
int i;
for (i = 0; i < a->n_words; i++)
igt_assert_eq_u32(a->crc[i], b->crc[i]);
}
/**
* igt_crc_to_string:
* @crc: pipe CRC value to print
*
* This formats @crc into a string buffer which is owned by igt_crc_to_string().
* The next call will override the buffer again, which makes this multithreading
* unsafe.
*
* This should only ever be used for diagnostic debug output.
*/
char *igt_crc_to_string(igt_crc_t *crc)
{
char buf[128];
if (crc->n_words == 5)
sprintf(buf, "%08x %08x %08x %08x %08x", crc->crc[0],
crc->crc[1], crc->crc[2], crc->crc[3], crc->crc[4]);
else
igt_assert(0);
return strdup(buf);
}
/* (6 fields, 8 chars each, space separated (5) + '\n') */
#define PIPE_CRC_LINE_LEN (6 * 8 + 5 + 1)
/* account for \'0' */
#define PIPE_CRC_BUFFER_LEN (PIPE_CRC_LINE_LEN + 1)
struct _igt_pipe_crc {
int ctl_fd;
int crc_fd;
int line_len;
int buffer_len;
enum pipe pipe;
enum intel_pipe_crc_source source;
};
static const char *pipe_crc_sources[] = {
"none",
"plane1",
"plane2",
"pf",
"pipe",
"TV",
"DP-B",
"DP-C",
"DP-D",
"auto"
};
static const char *pipe_crc_source_name(enum intel_pipe_crc_source source)
{
return pipe_crc_sources[source];
}
static bool igt_pipe_crc_do_start(igt_pipe_crc_t *pipe_crc)
{
char buf[64];
/* Stop first just to make sure we don't have lingering state left. */
igt_pipe_crc_stop(pipe_crc);
sprintf(buf, "pipe %s %s", kmstest_pipe_name(pipe_crc->pipe),
pipe_crc_source_name(pipe_crc->source));
errno = 0;
igt_assert_eq(write(pipe_crc->ctl_fd, buf, strlen(buf)), strlen(buf));
if (errno != 0)
return false;
return true;
}
static void igt_pipe_crc_pipe_off(int fd, enum pipe pipe)
{
char buf[32];
sprintf(buf, "pipe %s none", kmstest_pipe_name(pipe));
igt_assert_eq(write(fd, buf, strlen(buf)), strlen(buf));
}
static void igt_pipe_crc_reset(void)
{
int fd;
fd = igt_debugfs_open("i915_display_crc_ctl", O_WRONLY);
igt_pipe_crc_pipe_off(fd, PIPE_A);
igt_pipe_crc_pipe_off(fd, PIPE_B);
igt_pipe_crc_pipe_off(fd, PIPE_C);
close(fd);
}
static void pipe_crc_exit_handler(int sig)
{
igt_pipe_crc_reset();
}
/**
* igt_require_pipe_crc:
*
* Convenience helper to check whether pipe CRC capturing is supported by the
* kernel. Uses igt_skip to automatically skip the test/subtest if this isn't
* the case.
*/
void igt_require_pipe_crc(void)
{
const char *cmd = "pipe A none";
FILE *ctl;
size_t written;
int ret;
ctl = igt_debugfs_fopen("i915_display_crc_ctl", "r+");
igt_require_f(ctl,
"No display_crc_ctl found, kernel too old\n");
written = fwrite(cmd, 1, strlen(cmd), ctl);
ret = fflush(ctl);
igt_require_f((written == strlen(cmd) && ret == 0) || errno != ENODEV,
"CRCs not supported on this platform\n");
fclose(ctl);
}
/**
* igt_pipe_crc_new:
* @pipe: display pipe to use as source
* @source: CRC tap point to use as source
*
* This sets up a new pipe CRC capture object for the given @pipe and @source.
*
* Returns: A pipe CRC object if the given @pipe and @source. The library
* assumes that the source is always available since recent kernels support at
* least INTEL_PIPE_CRC_SOURCE_AUTO everywhere.
*/
igt_pipe_crc_t *
igt_pipe_crc_new(enum pipe pipe, enum intel_pipe_crc_source source)
{
igt_pipe_crc_t *pipe_crc;
char buf[128];
igt_install_exit_handler(pipe_crc_exit_handler);
pipe_crc = calloc(1, sizeof(struct _igt_pipe_crc));
pipe_crc->ctl_fd = igt_debugfs_open("i915_display_crc_ctl", O_WRONLY);
igt_assert(pipe_crc->ctl_fd != -1);
sprintf(buf, "i915_pipe_%s_crc", kmstest_pipe_name(pipe));
pipe_crc->crc_fd = igt_debugfs_open(buf, O_RDONLY);
igt_assert(pipe_crc->crc_fd != -1);
pipe_crc->line_len = PIPE_CRC_LINE_LEN;
pipe_crc->buffer_len = PIPE_CRC_BUFFER_LEN;
pipe_crc->pipe = pipe;
pipe_crc->source = source;
return pipe_crc;
}
/**
* igt_pipe_crc_free:
* @pipe_crc: pipe CRC object
*
* Frees all resources associated with @pipe_crc.
*/
void igt_pipe_crc_free(igt_pipe_crc_t *pipe_crc)
{
if (!pipe_crc)
return;
close(pipe_crc->ctl_fd);
close(pipe_crc->crc_fd);
free(pipe_crc);
}
/**
* igt_pipe_crc_start:
* @pipe_crc: pipe CRC object
*
* Starts the CRC capture process on @pipe_crc.
*/
void igt_pipe_crc_start(igt_pipe_crc_t *pipe_crc)
{
igt_crc_t *crcs = NULL;
igt_assert(igt_pipe_crc_do_start(pipe_crc));
/*
* For some no yet identified reason, the first CRC is bonkers. So
* let's just wait for the next vblank and read out the buggy result.
*
* On CHV sometimes the second CRC is bonkers as well, so don't trust
* that one either.
*/
igt_pipe_crc_get_crcs(pipe_crc, 2, &crcs);
free(crcs);
}
/**
* igt_pipe_crc_stop:
* @pipe_crc: pipe CRC object
*
* Stops the CRC capture process on @pipe_crc.
*/
void igt_pipe_crc_stop(igt_pipe_crc_t *pipe_crc)
{
char buf[32];
sprintf(buf, "pipe %s none", kmstest_pipe_name(pipe_crc->pipe));
igt_assert_eq(write(pipe_crc->ctl_fd, buf, strlen(buf)), strlen(buf));
}
static bool pipe_crc_init_from_string(igt_crc_t *crc, const char *line)
{
int n;
crc->n_words = 5;
n = sscanf(line, "%8u %8x %8x %8x %8x %8x", &crc->frame, &crc->crc[0],
&crc->crc[1], &crc->crc[2], &crc->crc[3], &crc->crc[4]);
return n == 6;
}
static bool read_one_crc(igt_pipe_crc_t *pipe_crc, igt_crc_t *out)
{
ssize_t bytes_read;
char buf[pipe_crc->buffer_len];
igt_set_timeout(5, "CRC reading");
bytes_read = read(pipe_crc->crc_fd, &buf, pipe_crc->line_len);
igt_reset_timeout();
igt_assert_eq(bytes_read, pipe_crc->line_len);
buf[bytes_read] = '\0';
if (!pipe_crc_init_from_string(out, buf))
return false;
return true;
}
/**
* igt_pipe_crc_get_crcs:
* @pipe_crc: pipe CRC object
* @n_crcs: number of CRCs to capture
* @out_crcs: buffer pointer for the captured CRC values
*
* Read @n_crcs from @pipe_crc. This function blocks until @n_crcs are
* retrieved. @out_crcs is alloced by this function and must be released with
* free() by the caller.
*
* Callers must start and stop the capturing themselves by calling
* igt_pipe_crc_start() and igt_pipe_crc_stop().
*/
void
igt_pipe_crc_get_crcs(igt_pipe_crc_t *pipe_crc, int n_crcs,
igt_crc_t **out_crcs)
{
igt_crc_t *crcs;
int n = 0;
crcs = calloc(n_crcs, sizeof(igt_crc_t));
do {
igt_crc_t *crc = &crcs[n];
if (!read_one_crc(pipe_crc, crc))
continue;
n++;
} while (n < n_crcs);
*out_crcs = crcs;
}
static void crc_sanity_checks(igt_crc_t *crc)
{
int i;
bool all_zero = true;
for (i = 0; i < crc->n_words; i++) {
igt_warn_on_f(crc->crc[i] == 0xffffffff,
"Suspicious CRC: it looks like the CRC "
"read back was from a register in a powered "
"down well\n");
if (crc->crc[i])
all_zero = false;
}
igt_warn_on_f(all_zero, "Suspicious CRC: All values are 0.\n");
}
/**
* igt_pipe_crc_collect_crc:
* @pipe_crc: pipe CRC object
* @out_crc: buffer for the captured CRC values
*
* Read a single CRC from @pipe_crc. This function blocks until the CRC is
* retrieved. @out_crc must be allocated by the caller.
*
* This function takes care of the pipe_crc book-keeping, it will start/stop
* the collection of the CRC.
*
* This function also calls the interactive debug with the "crc" domain, so you
* can make use of this feature to actually see the screen that is being CRC'd.
*/
void igt_pipe_crc_collect_crc(igt_pipe_crc_t *pipe_crc, igt_crc_t *out_crc)
{
igt_debug_wait_for_keypress("crc");
igt_pipe_crc_start(pipe_crc);
read_one_crc(pipe_crc, out_crc);
igt_pipe_crc_stop(pipe_crc);
crc_sanity_checks(out_crc);
}
/*
* Drop caches
*/
/**
* igt_drop_caches_set:
* @val: bitmask for DROP_* values
*
* This calls the debugfs interface the drm/i915 GEM driver exposes to drop or
* evict certain classes of gem buffer objects.
*/
void igt_drop_caches_set(uint64_t val)
{
int fd;
char data[19];
size_t nbytes;
sprintf(data, "0x%" PRIx64, val);
fd = igt_debugfs_open("i915_gem_drop_caches", O_WRONLY);
igt_assert(fd >= 0);
do {
nbytes = write(fd, data, strlen(data) + 1);
} while (nbytes == -1 && (errno == EINTR || errno == EAGAIN));
igt_assert(nbytes == strlen(data) + 1);
close(fd);
}
/*
* Prefault control
*/
#define PREFAULT_DEBUGFS "/sys/module/i915/parameters/prefault_disable"
static void igt_prefault_control(bool enable)
{
const char *name = PREFAULT_DEBUGFS;
int fd;
char buf[2] = {'Y', 'N'};
int index;
fd = open(name, O_RDWR);
igt_require(fd >= 0);
if (enable)
index = 1;
else
index = 0;
igt_require(write(fd, &buf[index], 1) == 1);
close(fd);
}
static void enable_prefault_at_exit(int sig)
{
igt_enable_prefault();
}
/**
* igt_disable_prefault:
*
* Disable prefaulting in certain gem ioctls through the debugfs interface. As
* usual this installs an exit handler to clean up and re-enable prefaulting
* even when the test exited abnormally.
*
* igt_enable_prefault() will enable normale operation again.
*/
void igt_disable_prefault(void)
{
igt_prefault_control(false);
igt_install_exit_handler(enable_prefault_at_exit);
}
/**
* igt_enable_prefault:
*
* Enable prefault (again) through the debugfs interface.
*/
void igt_enable_prefault(void)
{
igt_prefault_control(true);
}
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