nouveau/headers: Add Rust bindings for texture headers

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27397>

src/nouveau/headers/meson.build

@@ -77,6 +77,16 @@ if with_nouveau_vk
                  '--out-rs', '@OUTPUT0@'],
       depend_files: nvk_cl_header_depend_files,
     )
+
+    if cl.endswith('97')
+      cl_rs_generated += custom_target(
+        'nvh_' + cl + 'tex.rs',
+        input : ['struct_parser.py', 'nvidia/classes/'+cl+'tex.h'],
+        output : ['nvh_'+cl+'_tex.rs'],
+        command : [prog_python, '@INPUT0@', '--in-h', '@INPUT1@',
+                   '--out-rs', '@OUTPUT0@']
+      )
+    endif
   endforeach
 
   _nvidia_headers_lib_rs = custom_target(

src/nouveau/headers/struct_parser.py

@@ -0,0 +1,149 @@
+#! /usr/bin/env python3
+#
+# Copyright © 2024 Collabora Ltd. and Red Hat Inc.
+# SPDX-License-Identifier: MIT
+
+import argparse
+import os.path
+import re
+import sys
+
+from collections import namedtuple
+from mako.template import Template
+
+TEMPLATE_RS = Template("""\
+// Copyright © 2024 Collabora Ltd. and Red Hat Inc.
+// SPDX-License-Identifier: MIT
+
+// This file is generated by struct_parser.py. DO NOT EDIT!
+
+use std::ops::Range;
+
+% for s in structs:
+    % for f in s.fields:
+pub const ${s.name}_${f.name}: Range<usize> = ${f.lo}..${f.hi + 1};
+        % for e in f.enums:
+pub const ${s.name}_${f.name}_${e.name}: u32 = ${e.value};
+        % endfor
+    % endfor
+% endfor
+""")
+
+STRUCTS = [
+    'TEXHEADV2',
+    'TEXHEADV3',
+    'TEXHEAD_BL',
+    'TEXHEAD_1D',
+    'TEXHEAD_PITCH',
+    # This one goes last because it's a substring of the others
+    'TEXHEAD',
+    'TEXSAMP',
+]
+
+Enum = namedtuple('Enum', ['name', 'value'])
+
+class Field(object):
+    def __init__(self, name, lo, hi):
+        self.name = name
+        self.lo = lo
+        self.hi = hi
+        self.enums = []
+
+    def add_enum(self, name, value):
+        self.enums.append(Enum(name, value))
+
+class Struct(object):
+    def __init__(self, name):
+        self.name = name
+        self.fields = []
+
+    def add_field(self, name, lo, hi):
+        self.fields.append(Field(name, lo, hi))
+
+DRF_RE = re.compile(r'(?P<hi>[0-9]+):(?P<lo>[0-9]+)')
+FIELD_NAME_RE = re.compile(r'_?(?P<dw>[0-9]+)?_?(?P<name>.*)')
+MW_RE = re.compile(r'MW\((?P<hi>[0-9]+):(?P<lo>[0-9]+)\)')
+
+def parse_header(nvcl, file):
+    structs = {}
+    for line in file:
+        line = line.strip().split()
+        if not line:
+            continue
+
+        if line[0] != '#define':
+            continue
+
+        if not line[1].startswith(nvcl):
+            continue
+
+        name = line[1][(len(nvcl)+1):]
+
+        struct = None
+        for s in STRUCTS:
+            if name.startswith(s):
+                if s not in structs:
+                    structs[s] = Struct(s)
+                struct = structs[s]
+                name = name[len(s):]
+                break
+
+        if struct is None:
+            continue
+
+        name_m = FIELD_NAME_RE.match(name)
+        name = name_m.group('name')
+
+        drf = DRF_RE.match(line[2])
+        mw = MW_RE.match(line[2])
+        if drf:
+            dw = int(name_m.group('dw'))
+            lo = int(drf.group('lo')) + dw * 32
+            hi = int(drf.group('hi')) + dw * 32
+            struct.add_field(name, lo, hi)
+        elif mw:
+            lo = int(mw.group('lo'))
+            hi = int(mw.group('hi'))
+            struct.add_field(name, lo, hi)
+        else:
+            for f in struct.fields:
+                if name.startswith(f.name + '_'):
+                    name = name[(len(f.name)+1):]
+                    f.add_enum(name, line[2])
+
+    return list(structs.values())
+
+NVCL_RE = re.compile(r'cl(?P<clsver>[0-9a-f]{4}).*')
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--out-rs', required=True, help='Output Rust file.')
+    parser.add_argument('--in-h',
+                        help='Input class header file.',
+                        required=True)
+    args = parser.parse_args()
+
+    clheader = os.path.basename(args.in_h)
+    nvcl = NVCL_RE.match(clheader).group('clsver')
+    nvcl = nvcl.upper()
+    nvcl = "NV" + nvcl
+
+    with open(args.in_h, 'r', encoding='utf-8') as f:
+        structs = parse_header(nvcl, f)
+
+    try:
+        with open(args.out_rs, 'w', encoding='utf-8') as f:
+            f.write(TEMPLATE_RS.render(structs=structs))
+
+    except Exception:
+        # In the event there's an error, this imports some helpers from mako
+        # to print a useful stack trace and prints it, then exits with
+        # status 1, if python is run with debug; otherwise it just raises
+        # the exception
+        import sys
+        from mako import exceptions
+        print(exceptions.text_error_template().render(), file=sys.stderr)
+        sys.exit(1)
+
+if __name__ == '__main__':
+    main()