drm/i915/guc: Fix doorbell id selection

We are passing parameters in the wrong order to find next zero bit, and
when it doesn't find anything it returns size (offset in the code), which
is always zero.

For reference the function is defined as:
find_next_bit( *addr, size, offset )

The incorrect parameter order was added by commit abddffdf36
("drm/i915/guc: Sanitize GuC client initialization"). Luckily, currently
we only use a single guc client and a single doorbell, which happens to be
zero; therefore it isn't necessary to backport this fix (which would be for
v4.12).

Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170531000546.30762-1-michel.thierry@intel.com
This commit is contained in:
Michel Thierry 2017-05-30 17:05:46 -07:00 committed by Joonas Lahtinen
parent bef8c056fb
commit 7f1ea2ac30

View file

@ -105,7 +105,7 @@ static int __reserve_doorbell(struct i915_guc_client *client)
end += offset;
}
id = find_next_zero_bit(client->guc->doorbell_bitmap, offset, end);
id = find_next_zero_bit(client->guc->doorbell_bitmap, end, offset);
if (id == end)
return -ENOSPC;