| Message ID | 20190627122348.5833-2-kraxel@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/bochs: cleanups and framebuffer setup fix. | expand |
Hi Am 27.06.19 um 14:23 schrieb Gerd Hoffmann: > drm clients like the generic framebuffer emulation keep a permanent > vmap active, which in turn has a permanent pin. This pin needs to > be in vram, otherwise we can't display the framebuffer. > > Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> > --- > drivers/gpu/drm/drm_gem_vram_helper.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c > index 4de782ca26b2..c724876c6f2a 100644 > --- a/drivers/gpu/drm/drm_gem_vram_helper.c > +++ b/drivers/gpu/drm/drm_gem_vram_helper.c > @@ -592,7 +592,7 @@ void *drm_gem_vram_driver_gem_prime_vmap(struct drm_gem_object *gem) > int ret; > void *base; > > - ret = drm_gem_vram_pin(gbo, 0); > + ret = drm_gem_vram_pin(gbo, DRM_GEM_VRAM_PL_FLAG_VRAM); I have a patch set that converts ast and mgag200 to generic framebuffer emulation with a shadow FB. The actual BO is mapped by the fbdev code on demand to update its content. Permanently mapping the fb console's BO would consume too much display memory. This requires the pin function's placement flag to be 0, so the BO is mapped in system memory by default. The proposed patch breaks this. Some ideas for solving this: 1) Introduce a default_placement field in struct drm_gem_vram_helper where this flag can be configured. I'd favor this option. 2) Introduce a separate callback function for pinning to vram. The driver would have to set the correct function pointers. 3) Pin the fb console buffer manually from within the bochs driver. Best regards Thomas > if (ret) > return NULL; > base = drm_gem_vram_kmap(gbo, true, NULL); >
Hi, > 1) Introduce a default_placement field in struct drm_gem_vram_helper > where this flag can be configured. I'd favor this option. > 2) Introduce a separate callback function for pinning to vram. The > driver would have to set the correct function pointers. > 3) Pin the fb console buffer manually from within the bochs driver. Hmm. Before calling drm_fbdev_generic_setup() the bo doesn't exist yet and when the function returns it is already vmapped and pinned I think. So (3) isn't easily doable. (1) looks best to me. cheers, Gerd
Hi Am 27.06.19 um 17:16 schrieb Gerd Hoffmann: > Hi, > >> 1) Introduce a default_placement field in struct drm_gem_vram_helper >> where this flag can be configured. I'd favor this option. > >> 2) Introduce a separate callback function for pinning to vram. The >> driver would have to set the correct function pointers. > >> 3) Pin the fb console buffer manually from within the bochs driver. > > Hmm. Before calling drm_fbdev_generic_setup() the bo doesn't exist yet > and when the function returns it is already vmapped and pinned I think. > > So (3) isn't easily doable. (1) looks best to me. For my patches, it's OK to have to BO pinned to VRAM by default. As the BO will be unmapped most of the time, I can change this flag at any time. Best regards Thomas > cheers, > Gerd >
Am 27.06.19 um 17:54 schrieb Thomas Zimmermann: > Hi > > Am 27.06.19 um 17:16 schrieb Gerd Hoffmann: >> Hi, >> >>> 1) Introduce a default_placement field in struct drm_gem_vram_helper >>> where this flag can be configured. I'd favor this option. >> >>> 2) Introduce a separate callback function for pinning to vram. The >>> driver would have to set the correct function pointers. >> >>> 3) Pin the fb console buffer manually from within the bochs driver. >> >> Hmm. Before calling drm_fbdev_generic_setup() the bo doesn't exist yet >> and when the function returns it is already vmapped and pinned I think. >> >> So (3) isn't easily doable. (1) looks best to me. > > For my patches, it's OK to have to BO pinned to VRAM by default. As the > BO will be unmapped most of the time, I can change this flag at any time. So, yeah, option 1 ... > Best regards > Thomas > >> cheers, >> Gerd >> > > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel >
diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c index 4de782ca26b2..c724876c6f2a 100644 --- a/drivers/gpu/drm/drm_gem_vram_helper.c +++ b/drivers/gpu/drm/drm_gem_vram_helper.c @@ -592,7 +592,7 @@ void *drm_gem_vram_driver_gem_prime_vmap(struct drm_gem_object *gem) int ret; void *base; - ret = drm_gem_vram_pin(gbo, 0); + ret = drm_gem_vram_pin(gbo, DRM_GEM_VRAM_PL_FLAG_VRAM); if (ret) return NULL; base = drm_gem_vram_kmap(gbo, true, NULL);
drm clients like the generic framebuffer emulation keep a permanent vmap active, which in turn has a permanent pin. This pin needs to be in vram, otherwise we can't display the framebuffer. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> --- drivers/gpu/drm/drm_gem_vram_helper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)