[igt-dev] [Intel-gfx] [PATCH i-g-t] tests: Add exercise for fbdev

[Chris Wilson]

Quoting Ville Syrjälä (2019-11-14 12:18:01)
> On Wed, Nov 13, 2019 at 07:28:54PM +0000, Chris Wilson wrote:
> > I broke fb_mmap() proving that we need a test in CI!
> > 
> > References: https://bugs.freedesktop.org/show_bug.cgi?id=112256
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > ---
> >  tests/Makefile.sources                |  1 +
> >  tests/fbdev.c                         | 69 +++++++++++++++++++++++++++
> >  tests/intel-ci/fast-feedback.testlist |  1 +
> >  tests/meson.build                     |  1 +
> >  4 files changed, 72 insertions(+)
> >  create mode 100644 tests/fbdev.c
> > 
> > diff --git a/tests/Makefile.sources b/tests/Makefile.sources
> > index abf1e2fc1..6b1d4cb22 100644
> > --- a/tests/Makefile.sources
> > +++ b/tests/Makefile.sources
> > @@ -24,6 +24,7 @@ TESTS_progs = \
> >       drm_import_export \
> >       drm_mm \
> >       drm_read \
> > +     fbdev \
> >       kms_3d \
> >       kms_addfb_basic \
> >       kms_atomic \
> > diff --git a/tests/fbdev.c b/tests/fbdev.c
> > new file mode 100644
> > index 000000000..170f5dd52
> > --- /dev/null
> > +++ b/tests/fbdev.c
> > @@ -0,0 +1,69 @@
> > +/*
> > + * Copyright © 2019 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 "config.h"
> > +
> > +#include "igt.h"
> > +
> > +#include <fcntl.h>
> > +#include <string.h>
> > +#include <sys/ioctl.h>
> > +#include <sys/mman.h>
> > +#include <sys/stat.h>
> > +#include <sys/types.h>
> > +#include <unistd.h>
> > +
> > +#include <linux/fb.h>
> > +
> > +#include "igt.h"
> > +
> > +igt_main
> > +{
> > +     struct fb_var_screeninfo var_info;
> > +     struct fb_fix_screeninfo fix_info;
> > +     int fd = -1;
> > +
> > +     igt_fixture {
> > +             fd = open("/dev/fb0", O_RDWR);
> > +             igt_require_f(fd != -1, "/dev/fb0\n");
> 
> I suppose we may want to iterate over all the devices eventually.

Yup, pencil that in after multi-device support for igt lands :)
Or at least dynamic subtests.

> > +
> > +             igt_require(ioctl(fd, FBIOGET_VSCREENINFO, &var_info) == 0);
> > +             igt_require(ioctl(fd, FBIOGET_FSCREENINFO, &fix_info) == 0);
> > +     }
> > +
> > +     igt_subtest("mmap") {
> > +             unsigned long size;
> > +             void *map;
> > +
> > +             size = var_info.yres * fix_info.line_length;
> 
> Or maybe just fix.smem_len?

That sounds sensible, as that is the limit of the mappable area and not
just the screen. I cheated and just copied what ply-image was doing,
which had the desired effect of exploding.
 
> Either way
> Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> > +             map = mmap(NULL, size, PROT_WRITE, MAP_SHARED, fd, 0);
> > +             igt_assert(map != MAP_FAILED);
> > +
> > +             memset(map, 0, size);
> > +             munmap(map, size);
> 
> Another future idea would be to do a crc check to make sure we're
> actually affecting the screen contents when we poke at the thing.

And we probably want to check all the other bits and bobs of the fbdev
API -- at least the bare minimum as we must keep working for plymouth.
-Chris