ir3/a6xx,freedreno: account for resinfo return size dependency on IBO_0_FMT

On a6xx resinfo returns size in bytes divided by IBO_0_FMT format size
(not just size in dwords), we have to shift it back to NIR meaning which
is size in bytes.

Make freedreno use 16b buffers when they are supported in order to be
able to depend on hardware capabilities when lowering ssbo size.

Fixes: ce1a381e57 "turnip: enable VK_KHR_16bit_storage on A650"

Fixes cts tests:
    dEQP-VK.ssbo.unsized_array_length.float_offset_explicit_size
    dEQP-VK.ssbo.unsized_array_length.float_no_offset_whole_size
    dEQP-VK.compute.basic.write_multiple_unsized_arr_single_invocation
and many more

Signed-off-by: Danylo Piliaiev <dpiliaiev@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12485>

src/freedreno/ir3/ir3_compiler.c

@@ -126,6 +126,9 @@ ir3_compiler_create(struct fd_device *dev, const struct fd_dev_id *dev_id,
 
       compiler->tess_use_shared =
             fd_dev_info(compiler->dev_id)->a6xx.tess_use_shared;
+
+      compiler->storage_16bit =
+            fd_dev_info(compiler->dev_id)->a6xx.storage_16bit;
    } else {
       compiler->max_const_pipeline = 512;
       compiler->max_const_geom = 512;

src/freedreno/ir3/ir3_compiler.h

@@ -156,6 +156,9 @@ struct ir3_compiler {
 
    /* Whether private memory is supported */
    bool has_pvtmem;
+
+   /* True if 16-bit descriptors are used for both 16-bit and 32-bit access. */
+   bool storage_16bit;
 };
 
 void ir3_compiler_destroy(struct ir3_compiler *compiler);

src/freedreno/ir3/ir3_nir.c

@@ -303,20 +303,23 @@ ir3_nir_lower_ssbo_size_filter(const nir_instr *instr, const void *data)
 static nir_ssa_def *
 ir3_nir_lower_ssbo_size_instr(nir_builder *b, nir_instr *instr, void *data)
 {
+   uint8_t ssbo_size_to_bytes_shift = *(uint8_t *) data;
    nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
-   return nir_ishl(b, &intr->dest.ssa, nir_imm_int(b, 2));
+   return nir_ishl(b, &intr->dest.ssa, nir_imm_int(b, ssbo_size_to_bytes_shift));
 }
 
 /**
- * The resinfo opcode we have for getting the SSBO size on a6xx returns a number
- * of dwords, while the NIR intrinsic coming in is a number of bytes.  Switch
- * things so the NIR intrinsic in our backend means dwords.
+ * The resinfo opcode we have for getting the SSBO size on a6xx returns a byte
+ * length divided by IBO_0_FMT, while the NIR intrinsic coming in is a number of
+ * bytes. Switch things so the NIR intrinsic in our backend means dwords.
  */
 static bool
-ir3_nir_lower_ssbo_size(nir_shader *s)
+ir3_nir_lower_ssbo_size(nir_shader *s, bool storage_16bit)
 {
+   uint8_t ssbo_size_to_bytes_shift = storage_16bit ? 1 : 2;
    return nir_shader_lower_instructions(s, ir3_nir_lower_ssbo_size_filter,
-                                        ir3_nir_lower_ssbo_size_instr, NULL);
+                                        ir3_nir_lower_ssbo_size_instr,
+                                        &ssbo_size_to_bytes_shift);
 }
 
 void
@@ -563,7 +566,7 @@ ir3_nir_post_finalize(struct ir3_compiler *compiler, nir_shader *s)
    NIR_PASS_V(s, nir_lower_idiv, &idiv_options); /* idiv generated by cube lowering */
 
    if (compiler->gen >= 6)
-      OPT_V(s, ir3_nir_lower_ssbo_size);
+      OPT_V(s, ir3_nir_lower_ssbo_size, compiler->storage_16bit);
 
    ir3_optimize_loop(compiler, s);
 }

src/gallium/drivers/freedreno/a6xx/fd6_image.c

@@ -135,7 +135,6 @@ translate_image(struct fd6_image *img, const struct pipe_image_view *pimg)
 static void
 translate_buf(struct fd6_image *img, const struct pipe_shader_buffer *pimg)
 {
-   enum pipe_format format = PIPE_FORMAT_R32_UINT;
    struct pipe_resource *prsc = pimg->buffer;
    struct fd_resource *rsc = fd_resource(prsc);
 
@@ -144,6 +143,11 @@ translate_buf(struct fd6_image *img, const struct pipe_shader_buffer *pimg)
       return;
    }
 
+   const struct fd_dev_info *dev_info = fd_screen(prsc->screen)->info;
+   enum pipe_format format = dev_info->a6xx.storage_16bit
+                                ? PIPE_FORMAT_R16_UINT
+                                : PIPE_FORMAT_R32_UINT;
+
    img->prsc = prsc;
    img->pfmt = format;
    img->type = fd6_tex_type(prsc->target);
@@ -161,7 +165,7 @@ translate_buf(struct fd6_image *img, const struct pipe_shader_buffer *pimg)
    /* size is encoded with low 15b in WIDTH and high bits in HEIGHT,
     * in units of elements:
     */
-   unsigned sz = pimg->buffer_size / 4;
+   unsigned sz = pimg->buffer_size / (dev_info->a6xx.storage_16bit ? 2 : 4);
    img->width = sz & MASK(15);
    img->height = sz >> 15;
    img->depth = 0;