diff options
author | Kenneth Graunke <kenneth@whitecape.org> | 2017-03-02 18:27:32 -0800 |
---|---|---|
committer | Emil Velikov <emil.l.velikov@gmail.com> | 2017-04-12 11:32:28 +0100 |
commit | 05eb1c7f5935733ffc24e373e8ad9d94c14a737a (patch) | |
tree | 89cd07e92ff3f0958726b2389a07b0a575bcf0ce | |
parent | e7f872f7b8a897e188cf7b0462867c8f0b5d9397 (diff) |
i965: Skip register write detection when possible.
Detecting register write support by trial and error introduces a
stall at screen creation time, which it would be nice to avoid.
Certain command parser versions guarantee this will work (see the
giant comment in intelInitScreen2 below, or a few commits ago):
- Ivybridge: version >= 1 (kernel v3.16)
- Baytrail: version >= 2 (kernel v3.19)
- Haswell: version >= 7 (kernel v4.8)
For simplicity, we don't bother with version 1 in this patch.
This assumes that the user hasn't disabled aliasing PPGTT via a kernel
command line parameter. Don't do that - you're only breaking things.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
(cherry picked from commit 5e29af5f772c1e1b02a4cc46d2f7d3b5d2151ad8)
-rw-r--r-- | src/mesa/drivers/dri/i965/intel_screen.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/src/mesa/drivers/dri/i965/intel_screen.c b/src/mesa/drivers/dri/i965/intel_screen.c index 61b001e4439..5d1c7682e4d 100644 --- a/src/mesa/drivers/dri/i965/intel_screen.c +++ b/src/mesa/drivers/dri/i965/intel_screen.c @@ -1346,13 +1346,19 @@ err: static bool intel_detect_pipelined_so(struct intel_screen *screen) { + const struct gen_device_info *devinfo = &screen->devinfo; + /* Supposedly, Broadwell just works. */ - if (screen->devinfo.gen >= 8) + if (devinfo->gen >= 8) return true; - if (screen->devinfo.gen <= 6) + if (devinfo->gen <= 6) return false; + /* See the big explanation about command parser versions below */ + if (screen->cmd_parser_version >= (devinfo->is_haswell ? 7 : 2)) + return true; + /* We use SO_WRITE_OFFSET0 since you're supposed to write it (unlike the * statistics registers), and we already reset it to zero before using it. */ |