From: Marek Olšák <marek.ol...@amd.com>
Cc: 17.1 <mesa-sta...@lists.freedesktop.org>
---
src/gallium/drivers/radeonsi/si_state.c | 35 ++++++++++++++++++++++++++++++++-
1 file changed, 34 insertions(+), 1 deletion(-)
diff --git a/src/gallium/drivers/radeonsi/si_state.c
b/src/gallium/drivers/radeonsi/si_state.c
index a55f024..8a8705f 100644
--- a/src/gallium/drivers/radeonsi/si_state.c
+++ b/src/gallium/drivers/radeonsi/si_state.c
@@ -2969,21 +2969,54 @@ si_make_buffer_descriptor(struct si_screen *screen,
struct r600_resource *buf,
desc = util_format_description(format);
first_non_void = util_format_get_first_non_void_channel(format);
stride = desc->block.bits / 8;
num_format = si_translate_buffer_numformat(&screen->b.b, desc,
first_non_void);
data_format = si_translate_buffer_dataformat(&screen->b.b, desc,
first_non_void);
num_records = size / stride;
num_records = MIN2(num_records, (buf->b.b.width0 - offset) / stride);
- if (screen->b.chip_class == VI)
+ /* The NUM_RECORDS field has a different meaning depending on the chip,
+ * instruction type, STRIDE, and SWIZZLE_ENABLE.
+ *
+ * SI-CIK:
+ * - If STRIDE == 0, it's in byte units.
+ * - If STRIDE != 0, it's in units of STRIDE, used with inst.IDXEN.
+ *
+ * VI:
+ * - For SMEM and STRIDE == 0, it's in byte units.
+ * - For SMEM and STRIDE != 0, it's in units of STRIDE.
+ * - For VMEM and STRIDE == 0 or SWIZZLE_ENABLE == 0, it's in byte
units.
+ * - For VMEM and STRIDE != 0 and SWIZZLE_ENABLE == 1, it's in units of
STRIDE.
+ * NOTE: There is incompatibility between VMEM and SMEM opcodes due to
SWIZZLE_-
+ * ENABLE. The workaround is to set STRIDE = 0 if SWIZZLE_ENABLE
== 0 when
+ * using SMEM. This can be done in the shader by clearing STRIDE
with s_and.
+ * That way the same descriptor can be used by both SMEM and VMEM.
+ *
+ * GFX9:
+ * - For SMEM and STRIDE == 0, it's in byte units.
+ * - For SMEM and STRIDE != 0, it's in units of STRIDE.
+ * - For VMEM and inst.IDXEN == 0 or STRIDE == 0, it's in byte units.
+ * - For VMEM and inst.IDXEN == 1 and STRIDE != 0, it's in units of
STRIDE.
+ */
+ if (screen->b.chip_class >= GFX9)
+ /* When vindex == 0, LLVM sets IDXEN = 0, thus changing units
+ * from STRIDE to bytes. This works around it by setting
+ * NUM_RECORDS to at least the size of one element, so that
+ * the first element is readable when IDXEN == 0.
+ *
+ * TODO: Fix this in LLVM, but do we need a new intrinsic where
+ * IDXEN is enforced?
+ */
+ num_records = num_records ? MAX2(num_records, stride) : 0;
+ else if (screen->b.chip_class == VI)
num_records *= stride;
state[4] = 0;
state[5] = S_008F04_STRIDE(stride);
state[6] = num_records;
state[7] = S_008F0C_DST_SEL_X(si_map_swizzle(desc->swizzle[0])) |
S_008F0C_DST_SEL_Y(si_map_swizzle(desc->swizzle[1])) |
S_008F0C_DST_SEL_Z(si_map_swizzle(desc->swizzle[2])) |
S_008F0C_DST_SEL_W(si_map_swizzle(desc->swizzle[3])) |
S_008F0C_NUM_FORMAT(num_format) |
--
2.7.4
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/mesa-dev
