From: Matthew Auld Date: Mon, 26 Jun 2023 17:20:40 +0000 (+0100) Subject: drm/xe/mmio: update gt_count when probing multi-tile X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=356010a1a0c9fbe55d6c7e5dbd273a0fd224469e;p=linux.git drm/xe/mmio: update gt_count when probing multi-tile It looks like the single-tile PVC in CI dies during module load when doing the pcode init. From the logs we try to access the address 0000000000138124 which doesn't map to anything, however 0x138124 also looks to be the PCODE_MAILBOX register. So looks like the per-tile mmio register mapping is NULL. During probe the tile count is potentially trimmed, since we don't know the real count until we actually probe the device. This seems to be the case for single-tile PVC or similar devices. However it looks like the gt_count is never adjusted to respect this updated tile count. As a result when later doing some for_each_gt() loop, like we do for the pcode, we can get back some GT that maps to some non-existent tile which hasn't been properly set up, leading to crashes. Try to fix this by adjusting the gt_count after probing the tiles for real. v2: Fix typo so it actually builds References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/383 Signed-off-by: Matthew Auld Cc: Lucas De Marchi Cc: Matt Roper Reviewed-by: Ofir Bitton Signed-off-by: Rodrigo Vivi --- diff --git a/drivers/gpu/drm/xe/xe_mmio.c b/drivers/gpu/drm/xe/xe_mmio.c index 5effb21db9d4a..779f0a18a815a 100644 --- a/drivers/gpu/drm/xe/xe_mmio.c +++ b/drivers/gpu/drm/xe/xe_mmio.c @@ -335,6 +335,12 @@ static void xe_mmio_probe_tiles(struct xe_device *xe) adj_tile_count = xe->info.tile_count = REG_FIELD_GET(TILE_COUNT, mtcfg) + 1; + /* + * FIXME: Needs some work for standalone media, but should be impossible + * with multi-tile for now. + */ + xe->info.gt_count = xe->info.tile_count; + drm_info(&xe->drm, "tile_count: %d, adj_tile_count %d\n", xe->info.tile_count, adj_tile_count);