On Saturday, April 16, 2016 4:42:35 PM PDT Topi Pohjolainen wrote: > Otherwise switch from blorp to compute failes. Note that this now > follows the normal i965 upload logic found in gen7_upload_urb(). > > Effectively vs_size changes from 2 to 1 and vs_start from 2 to 4. > > Signed-off-by: Topi Pohjolainen <topi.pohjolai...@intel.com>
How about this explanation instead?
Previously, we hardcoded "VS URB Starting Address" to 2 (in 8kB chunks),
which meant VS URB data would start at an offset of 16kB.
However, on Haswell GT3 and Gen8+, we allocate the first 32kB for the
push constant region. This means that the PS push constant and VS URB
data regions overlap, which can lead to corruption.
Cc: mesa-sta...@lists.freedesktop.org
> ---
> src/mesa/drivers/dri/i965/gen7_blorp.cpp | 19 ++++++++++++++-----
> 1 file changed, 14 insertions(+), 5 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/gen7_blorp.cpp b/src/mesa/drivers/
dri/i965/gen7_blorp.cpp
> index 4debeb3..c1491ae 100644
> --- a/src/mesa/drivers/dri/i965/gen7_blorp.cpp
> +++ b/src/mesa/drivers/dri/i965/gen7_blorp.cpp
> @@ -47,8 +47,17 @@
> static void
> gen7_blorp_emit_urb_config(struct brw_context *brw)
> {
> + /* URB allocations must be done in 8k chunks. */
> + const unsigned chunk_size_bytes = 8192;
> const unsigned urb_size =
> (brw->gen >= 8 || (brw->is_haswell && brw->gt == 3)) ? 32 : 16;
> + const unsigned push_constant_bytes = 1024 * urb_size;
> + const unsigned push_constant_chunks =
> + push_constant_bytes / chunk_size_bytes;
> + const unsigned vs_size = 1;
Changing vs_size from 2 to 1 seems like a separate change to me, and
I doubt that it's necessary to fix the corruption that you're seeing.
The amount of VBO data we're uploading is 96 bytes (3 vertices * 2
attributes * 4 values * 4 bytes/float). Each size is 512 bits = 64
bytes. So based on the VBO data...a VS size of 2 seems right.
1 actually seems wrong, unless we don't need to account for the VUE
header (at which point it's 48 bytes, and 48 < 64 so it fits in 1.)
Does it still work if you make this "const unsigned vs_size = 2;"?
> + const unsigned vs_start = push_constant_chunks;
> + const unsigned vs_chunks =
> + DIV_ROUND_UP(brw->urb.min_vs_entries * vs_size * 64,
chunk_size_bytes);
>
> gen7_emit_push_constant_state(brw,
> urb_size / 2 /* vs_size */,
> @@ -59,17 +68,17 @@ gen7_blorp_emit_urb_config(struct brw_context *brw)
>
> gen7_emit_urb_state(brw,
> brw->urb.min_vs_entries /* num_vs_entries */,
> - 2 /* vs_size */,
> - 2 /* vs_start */,
> + vs_size,
> + vs_start,
> 0 /* num_hs_entries */,
> 1 /* hs_size */,
> - 2 /* hs_start */,
> + vs_start + vs_chunks /* hs_start */,
> 0 /* num_ds_entries */,
> 1 /* ds_size */,
> - 2 /* ds_start */,
> + vs_start + vs_chunks /* ds_start */,
> 0 /* num_gs_entries */,
> 1 /* gs_size */,
> - 2 /* gs_start */);
> + vs_start + vs_chunks /* gs_start */);
> }
>
>
>
signature.asc
Description: This is a digitally signed message part.
_______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
