lima: wire up anisotropic filtering

v2:
- AF seems to be log2 based, so convert accordingly

v3:
- actually expose AF

v4:
- REALLY expose AF
- remove log2 modifier assert
- use log2 modifier
- rename AF field
- advertise AF support in features

Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37189>

docs/features.txt

@@ -236,7 +236,7 @@ GL 4.6, GLSL 4.60 -- all DONE: radeonsi, virgl, zink, iris, crocus/gen7+, d3d12,
   GL_ARB_shader_draw_parameters                         DONE (freedreno/a6xx+, nvc0, crocus/gen6+, r600/evergreen+)
   GL_ARB_shader_group_vote                              DONE (freedreno/a6xx, nvc0, crocus, r600)
   GL_ARB_spirv_extensions                               DONE (freedreno, r600)
-  GL_ARB_texture_filter_anisotropic                     DONE (etnaviv/HALTI0, freedreno, nv50, nvc0, r600, softpipe, v3d, panfrost/v6+, crocus)
+  GL_ARB_texture_filter_anisotropic                     DONE (etnaviv/HALTI0, freedreno, nv50, nvc0, r600, softpipe, v3d, panfrost/v6+, crocus, lima)
   GL_ARB_transform_feedback_overflow_query              DONE (freedreno/a6xx+, nvc0, softpipe, crocus/gen6+, r600/evergreen+)
   GL_KHR_no_error                                       DONE (all drivers)
 

src/gallium/drivers/lima/genxml/common.xml

@@ -170,7 +170,7 @@
     <field name="Min Lod" start="1:12" size="8" type="ulod"/>
     <field name="Max Lod" start="1:20" size="8" type="ulod"/>
     <field name="Lod Bias" start="1:28" size="9" type="slod"/>
-    <field name="Unknown 3" start="2:5" size="3" type="hex"/>
+    <field name="Max Anisotropy" start="2:5" size="3" type="uint" modifier="log2"/>
     <field name="Has Stride" start="2:8" size="1" type="bool"/>
     <field name="Mipfilter" start="2:9" size="2" type="Mipfilter"/>
     <field name="Min Img Filter Nearest" start="2:11" size="1" type="bool"/>

src/gallium/drivers/lima/genxml/gen_pack.py

@@ -262,8 +262,6 @@ class Group(object):
                 print(f"   assert((values->{field.name} & {mask}) == 0);")
             elif field.modifier[0] == "minus":
                 print(f"   assert(values->{field.name} >= {field.modifier[1]});")
-            elif field.modifier[0] == "log2":
-                print(f"   assert(IS_POT_NONZERO(values->{field.name}));")
 
         for index in range(math.ceil(self.length / 4)):
             # Handle MBZ words

src/gallium/drivers/lima/lima_screen.c

@@ -210,6 +210,7 @@ lima_init_screen_caps(struct pipe_screen *screen)
    caps->max_point_size =
    caps->max_point_size_aa = 100.0f;
 
+   caps->anisotropic_filter = true;
    caps->max_texture_anisotropy = 16.0f;
 
    caps->max_texture_lod_bias = 15.0f;

src/gallium/drivers/lima/lima_texture.c

@@ -179,6 +179,8 @@ lima_update_tex_desc(struct lima_context *ctx, struct lima_sampler_state *sample
       desc.max_lod = max_lod;
       desc.lod_bias = sampler->base.lod_bias;
 
+      desc.max_anisotropy = sampler->base.max_anisotropy;
+
       switch (sampler->base.min_mip_filter) {
          case PIPE_TEX_MIPFILTER_LINEAR:
             desc.mipfilter = LIMA_MIPFILTER_LINEAR;