diff options
Diffstat (limited to 'kernel/gsp_display_engine.c')
| -rw-r--r-- | kernel/gsp_display_engine.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/kernel/gsp_display_engine.c b/kernel/gsp_display_engine.c index 98f85fe..c522a93 100644 --- a/kernel/gsp_display_engine.c +++ b/kernel/gsp_display_engine.c @@ -1419,6 +1419,30 @@ void gsp_disp_engine_pump(struct nv_vgpu_device *vgpu) 0xffc; /* + * Ring wrap / reset resync (eng4, 2026-11-12). nvEvoMakeRoom + * resets the driver's push pointer to the ring base when it + * wraps (writes a JUMP at the head, sets putOffset = 0), so the + * channel's PUT steps BACKWARD below our consumed. gsp_disp_run + * deliberately only publishes a GET that reached PUT exactly + * (see its r1630 comment), so a stale consumed left AHEAD of PUT + * can never resync: the parse from the old consumed hits the + * wrapped tail and never lands on the new PUT, GET stays past + * PUT forever, and nvidia-modeset's nvEvoMakeRoom / + * nvEvoPollForEmptyChannel spin (they break only on GET == + * put_offset). Seen live as core c57d PUT=0xcc8 GET=0xcd8 held + * for minutes with Xorg 100% in-kernel (nvkms_yield) and xdpyinfo + * unanswered. Re-seed consumed to the ring base and republish + * GET so the wrapped pushes are parsed from 0 (the driver's + * authoritative write pointer is PUT). + */ + if (put < s->consumed) { + s->consumed = 0; + s->last_put = 0; + gsp_disp_bar0_write(vgpu, + s->ctl_off + GSP_DISP_REG_GET, 0); + } + + /* * Raster line for the window channels: NVC57E_GET_LINE at * 0x208. Bit 15 set = blanking, 14:0 = line. A free-running * 1080p60 counter is enough for the driver's scanline/vblank |