[manuf] make OTP image consts a link-time dep

This updates the structure of the auto-generated OTP image key-value
contants header file (making it a C file now), and the `individualize_preop`
provisioning library to inject such contants as link-time dependency to
allow for easily adding (future) OTP SW configuration constants for
future OpenTitan SKUs.

Signed-off-by: Tim Trippel <[email protected]>

hw/ip/otp_ctrl/data/otp_ctrl_img.h.tpl → hw/ip/otp_ctrl/data/otp_ctrl_img.c.tpl

@@ -6,18 +6,12 @@ ${fileheader}
 // AUTOGENERATED. Do not edit this file by hand.
 // See the hw/ip/otp_ctrl/data README for details.
 
-#ifndef ${include_guard}
-#define ${include_guard}
+#include <stddef.h>
 
-// See the following include file for details on the types used in this header
-// file.
+// See the following include file for details on the types used in this file.
 #include "sw/device/silicon_creator/manuf/lib/otp_img_types.h"
 
-#include "otp_ctrl_regs.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif  // __cplusplus
+#include "otp_ctrl_regs.h"  // Generated.
 
 <%
   def ToPascalCase(in_str):
@@ -123,7 +117,8 @@ ${ConstTypeDefinition(item, data[partition_name]["alignment"])}
   alignment = data[partition_name]["alignment"]
 %>
 // Partition ${partition_name}
-static otp_kv_t ${"kOtpKv" + ToPascalCase(partition_name)}[] = {
+const size_t ${"kOtpKv" + ToPascalCase(partition_name) + "Size"} = ${len(data[partition_name]["items"])};
+const otp_kv_t ${"kOtpKv" + ToPascalCase(partition_name)}[] = {
   % for item in data[partition_name]["items"]:
   {
     .type = ${ToOtpValType(alignment)},
@@ -134,11 +129,3 @@ static otp_kv_t ${"kOtpKv" + ToPascalCase(partition_name)}[] = {
   % endfor
 };
 % endfor
-
-
-#ifdef __cplusplus
-}  // extern "C"
-#endif  // __cplusplus
-
-#endif  // ${include_guard}
-

hw/ip/otp_ctrl/data/sku_earlgrey_a0/BUILD

@@ -2,7 +2,7 @@
 # Licensed under the Apache License, Version 2.0, see LICENSE for details.
 # SPDX-License-Identifier: Apache-2.0
 
-load("//rules:otp.bzl", "otp_image_header", "otp_json")
+load("//rules:otp.bzl", "otp_image_consts", "otp_json")
 
 package(default_visibility = ["//visibility:public"])
 
@@ -12,12 +12,21 @@ otp_json(
     seed = "94259314771464387",
 )
 
-otp_image_header(
-    name = "otp_img_sku_earlgrey_a0_stage_individualize",
+otp_image_consts(
+    name = "otp_img_consts_c_file",
     src = ":otp_json_baseline",
     overlays = [
         "//hw/ip/otp_ctrl/data:otp_json_creator_sw_cfg",
         "//hw/ip/otp_ctrl/data:otp_json_owner_sw_cfg",
         "//hw/ip/otp_ctrl/data:otp_json_alert_digest_cfg",
     ],
 )
+
+cc_library(
+    name = "otp_img_consts",
+    srcs = [":otp_img_consts_c_file"],
+    deps = [
+        "//hw/ip/otp_ctrl/data:otp_ctrl_regs",
+        "//sw/device/silicon_creator/manuf/lib:otp_img_types",
+    ],
+)

rules/otp.bzl

@@ -39,7 +39,7 @@ format expected by the image generation tool.
 load("@bazel_skylib//rules:common_settings.bzl", "BuildSettingInfo")
 load("@bazel_skylib//lib:new_sets.bzl", "sets")
 load("//rules:host.bzl", "host_tools_transition")
-load("//rules:const.bzl", "CONST", "hex", "hex_digits")
+load("//rules:const.bzl", "CONST", "hex")
 
 def get_otp_images():
     """Returns a list of (otp_name, img_target) tuples.
@@ -246,8 +246,8 @@ otp_image = rule(
     },
 )
 
-def _otp_image_header(ctx):
-    output = ctx.actions.declare_file(ctx.attr.name + ".h")
+def _otp_image_consts_impl(ctx):
+    output = ctx.actions.declare_file(ctx.attr.name + ".c")
     args = ctx.actions.args()
     if not ctx.attr.verbose:
         args.add("--quiet")
@@ -257,34 +257,26 @@ def _otp_image_header(ctx):
     args.add("--lc-seed", ctx.attr.lc_seed[BuildSettingInfo].value)
     args.add("--otp-seed", ctx.attr.otp_seed[BuildSettingInfo].value)
     args.add("--img-cfg", ctx.file.src)
-    args.add("--header-template", ctx.file.header_template)
-    args.add("--header-out", "{}/{}.h".format(output.dirname, ctx.attr.name))
+    args.add("--c-template", ctx.file.c_template)
+    args.add("--c-out", "{}/{}.c".format(output.dirname, ctx.attr.name))
     args.add_all(ctx.files.overlays, before_each = "--add-cfg")
     ctx.actions.run(
         outputs = [output],
         inputs = [
             ctx.file.src,
-            ctx.file.header_template,
+            ctx.file.c_template,
             ctx.file.lc_state_def,
             ctx.file.mmap_def,
         ] + ctx.files.overlays,
         arguments = [args],
         executable = ctx.executable._tool,
     )
     return [
-        CcInfo(compilation_context = cc_common.create_compilation_context(
-            includes = depset([output.dirname]),
-            headers = depset([output]),
-            defines = depset(["RULE_NAME=\"{}\"".format(ctx.label.name)]),
-        )),
         DefaultInfo(files = depset([output]), runfiles = ctx.runfiles(files = [output])),
-        OutputGroupInfo(
-            header = depset([output]),
-        ),
     ]
 
-otp_image_header = rule(
-    implementation = _otp_image_header,
+otp_image_consts = rule(
+    implementation = _otp_image_consts_impl,
     attrs = {
         "src": attr.label(
             allow_single_file = [".json", ".hjson"],
@@ -316,9 +308,9 @@ otp_image_header = rule(
             default = "//hw/ip/otp_ctrl/data:otp_seed",
             doc = "Configuration override seed used to randomize OTP netlist constants.",
         ),
-        "header_template": attr.label(
+        "c_template": attr.label(
             allow_single_file = True,
-            default = "//hw/ip/otp_ctrl/data:otp_ctrl_img.h.tpl",
+            default = "//hw/ip/otp_ctrl/data:otp_ctrl_img.c.tpl",
             doc = "OTP image header template.",
         ),
         "verbose": attr.bool(

sw/device/silicon_creator/manuf/lib/BUILD

@@ -106,21 +106,31 @@ opentitan_functest(
 )
 
 cc_library(
-    name = "individualize_preop",
-    srcs = ["individualize_preop.c"],
-    hdrs = [
+    name = "individualize_preop_generic",
+    srcs = [
+        "individualize_preop.c",
         "individualize_preop.h",
     ],
     deps = [
         ":otp_img",
-        "//hw/ip/otp_ctrl/data/sku_earlgrey_a0:otp_img_sku_earlgrey_a0_stage_individualize",
+        ":otp_img_types",
         "//sw/device/lib/base:status",
         "//sw/device/lib/dif:otp_ctrl",
         "//sw/device/lib/testing:lc_ctrl_testutils",
         "//sw/device/lib/testing:otp_ctrl_testutils",
     ],
 )
 
+# As more SKUs are created with different OTP software configuration partitions,
+# libraries can be added accordingly.
+cc_library(
+    name = "individualize_preop_sku_earlgrey_a0",
+    deps = [
+        ":individualize_preop_generic",
+        "//hw/ip/otp_ctrl/data/sku_earlgrey_a0:otp_img_consts",
+    ],
+)
+
 opentitan_functest(
     name = "individualize_preop_functest",
     srcs = ["individualize_preop_functest.c"],
@@ -132,7 +142,7 @@ opentitan_functest(
         "cw310_rom_with_fake_keys",
     ],
     deps = [
-        ":individualize_preop",
+        ":individualize_preop_sku_earlgrey_a0",
         "//hw/ip/otp_ctrl/data:otp_ctrl_regs",
         "//hw/top_earlgrey/sw/autogen:top_earlgrey",
         "//sw/device/lib/base:status",

sw/device/silicon_creator/manuf/lib/individualize_preop.c

@@ -4,14 +4,14 @@
 
 #include "sw/device/silicon_creator/manuf/lib/individualize_preop.h"
 
-#include "otp_img_sku_earlgrey_a0_stage_individualize.h"  // Generated.
 #include "sw/device/lib/dif/dif_otp_ctrl.h"
 #include "sw/device/silicon_creator/manuf/lib/otp_img.h"
+#include "sw/device/silicon_creator/manuf/lib/otp_img_types.h"
 
 status_t manuf_individualize_device_sw_cfg(const dif_otp_ctrl_t *otp_ctrl) {
   TRY(otp_img_write(otp_ctrl, kDifOtpCtrlPartitionCreatorSwCfg,
-                    kOtpKvCreatorSwCfg, ARRAYSIZE(kOtpKvCreatorSwCfg)));
+                    kOtpKvCreatorSwCfg, kOtpKvCreatorSwCfgSize));
   TRY(otp_img_write(otp_ctrl, kDifOtpCtrlPartitionOwnerSwCfg, kOtpKvOwnerSwCfg,
-                    ARRAYSIZE(kOtpKvOwnerSwCfg)));
+                    kOtpKvOwnerSwCfgSize));
   return OK_STATUS();
 }

sw/device/silicon_creator/manuf/lib/individualize_preop.h

@@ -7,6 +7,19 @@
 
 #include "sw/device/lib/base/status.h"
 #include "sw/device/lib/dif/dif_otp_ctrl.h"
+#include "sw/device/silicon_creator/manuf/lib/otp_img.h"
+
+/**
+ * OTP Creator Software Configuration Partition.
+ */
+extern const size_t kOtpKvCreatorSwCfgSize;
+extern const otp_kv_t kOtpKvCreatorSwCfg[];
+
+/**
+ * OTP Owner Software Configuration Partition.
+ */
+extern const size_t kOtpKvOwnerSwCfgSize;
+extern const otp_kv_t kOtpKvOwnerSwCfg[];
 
 /**
  * Configures the CREATOR_SW_CFG and OWNER_SW_CFG OTP partitions.

sw/device/silicon_creator/manuf/tests/BUILD

@@ -311,7 +311,7 @@ opentitan_ram_binary(
         "//sw/device/lib/testing:pinmux_testutils",
         "//sw/device/lib/testing/test_framework:check",
         "//sw/device/lib/testing/test_framework:status",
-        "//sw/device/silicon_creator/manuf/lib:individualize_preop",
+        "//sw/device/silicon_creator/manuf/lib:individualize_preop_sku_earlgrey_a0",
         "//sw/device/silicon_creator/manuf/lib:isolated_flash_partition",
         "//sw/device/silicon_creator/manuf/lib:sram_program_linker_script",
         "//sw/device/silicon_creator/manuf/lib:sram_start",

util/design/gen-otp-img.py

@@ -207,18 +207,18 @@ def main():
                         The mapping must be bijective - otherwise this will generate
                         an error.
                         ''')
-    parser.add_argument('--header-template',
+    parser.add_argument('--c-template',
                         type=Path,
                         metavar='<path>',
                         help='''
-                        Template file used to generate C header version of the OTP image.
-                        This flag is only required when --header-out is set.
+                        Template file used to generate C version of the OTP image.
+                        This flag is only required when --c-out is set.
                         ''')
-    parser.add_argument('--header-out',
+    parser.add_argument('--c-out',
                         type=Path,
                         metavar='<path>',
                         help='''
-                        C header output path. Requires the --header-template flag to be
+                        C output path. Requires the --c-template flag to be
                         set. The --out flag is ignored when this flag is set.
                         ''')
 
@@ -280,12 +280,10 @@ def main():
     file_header = '// Generated on {} with\n// $ gen-otp-img.py {}\n//\n'.format(
         dtstr, argstr)
 
-    if args.header_out:
-        log.info(f'Generating header file: {args.header_out}')
-        file_body = otp_mem_img.generate_headerfile(args.header_out,
-                                                    file_header,
-                                                    args.header_template)
-        with open(args.header_out, 'wb') as outfile:
+    if args.c_out:
+        log.info(f'Generating C file: {args.c_out}')
+        file_body = otp_mem_img.generate_c_file(file_header, args.c_template)
+        with open(args.c_out, 'wb') as outfile:
             outfile.write(file_body.encode('utf-8'))
         exit(0)
 

util/design/lib/OtpMemImg.py

@@ -529,12 +529,10 @@ def streamout_memfile(self) -> Tuple[str, int]:
         return _to_memfile_with_ecc(data, annotation, self.lc_state.config,
                                     self.data_perm)
 
-    def generate_headerfile(self, outfile: str, fileheader: str,
-                            templatefile: Path) -> str:
-        '''Generates header file with provided `header` and `templatefile`.
+    def generate_c_file(self, fileheader: str, templatefile: Path) -> str:
+        '''Generates C file with provided `header` and `templatefile`.
 
         Args:
-            outfile: Output file path. Used to generate include guards.
             fileheader: Header to be appended to autogenerated file.
             templatefile: Mako template used to generate header file.
         Returns:
@@ -573,12 +571,8 @@ def generate_headerfile(self, outfile: str, fileheader: str,
                 'items': items,
             }
 
-        include_guard = common.path_to_include_guard(outfile)
-
         with open(templatefile, 'r') as tplfile:
             tpl = Template(tplfile.read())
-            result = tpl.render(include_guard=include_guard,
-                                fileheader=fileheader,
-                                data=data)
+            result = tpl.render(fileheader=fileheader, data=data)
 
         return result