[bazel] Allocate CW310s based on extra resources

WIP requires custom bazel binary.

Signed-off-by: Drew Macrae <drewmacrae@google.com>

.bazelrc

@@ -43,12 +43,8 @@ coverage:coverage_clang --repo_env=BAZEL_LLVM_COV=/usr/bin/llvm-cov
 # cached previously. See https://bazel.build/configure/coverage?hl=en#remote-execution
 coverage:coverage_clang --nocache_test_results
 
-# Verilator is built for 4 cores and can time out if bazel is running more
-# than 1 test per four cores.
-# Until we get the built-in tag "cpu:4" to work for verilator tests, we can run
-# 1 test per 4 cores to avoid verilator performance falloff and timeouts we'd
-# otherwise see on machines with fewer than 40 cores.
-test --local_test_jobs=HOST_CPUS*0.25
+# Allow bazel to allocate tests to 1 cw310 board.
+test --local_extra_resources=cw310=1
 
 # We have verilator tests that take more than an hour to complete
 test --test_timeout=60,300,1500,7200

rules/opentitan_gdb_test.bzl

@@ -237,7 +237,7 @@ def opentitan_gdb_fpga_cw310_test(
     _opentitan_gdb_fpga_cw310_test(
         tags = tags + [
             "cw310",
-            "exclusive",  # Prevent FPGA tests from running concurrently.
+            "resources:cw310:1",  # Prevent FPGA tests from running concurrently.
             "jtag",
         ],
         opentitantool_cw310_uarts = select({

rules/opentitan_test.bzl

@@ -221,7 +221,7 @@ def cw310_params(
     ]
     required_tags = [
         "cw310",
-        "exclusive",
+        "resources:cw310:1",
     ]
     kwargs.update(
         args = default_args + args,

sw/device/silicon_creator/rom/e2e/BUILD

@@ -3455,7 +3455,6 @@ test_suite(
         rom_kind = "Rom",
         tags = [
             "cw310_rom",
-            "exclusive",
             "vivado",
         ] + maybe_skip_in_ci(lc_state_val),
     )