util/cbfstool: Decouple elogtool from vboot_ref flashrom code

Currently elogtool sub-proccesses flashrom as calling libflashrom
requires a missing function from the previous flashrom release.
Pending a new release of flashrom we must continue to use subprocess.

However the current subprocess wrapper implementation lives in
vboot_reference which is a git sub-module of coreboot. This causes
all sorts of grief keeping a subprocess ABI stable from vboot_reference
when the rest of vboot_reference builds of HEAD of the flashrom tree
(i.e., using unreleased libflashrom functions). In order to not keep
finding ourseleves in a bind between the two separately moving trees
with different build environments, decouple elogtool with its own
mini copy of flashrom subprocess wrapping logic.

Squash in,
 util/cbfstool/elogtool.c: Convert args into struct in flashrom helper

  vboot signatures for flashrom r/w helpers changed in the upstream
  commit bd2971326ee94fc5. Reflect the change here to allow vboot ref
  and coreboot to realign.

BUG=b:207808292,b:231152447
TEST=builds with vboot_ref uprev.

Change-Id: I04925e4d9a44b52e4a6fb6f9cec332cab2c7c725
Signed-off-by: Edward O'Callaghan <quasisec@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/65055
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/util/cbfstool/flashrom.h b/util/cbfstool/flashrom.h
new file mode 100644
index 0000000000..0db2194973
--- /dev/null
+++ b/util/cbfstool/flashrom.h
@@ -0,0 +1,33 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Host utilities to execute flashrom command.
+ */
+
+#include <stdint.h>
+#include "common.h" /* from cbfstool for buffer API. */
+
+/**
+ * Read using flashrom into an allocated buffer.
+ *
+ * @param buffer	The parameter that contains the buffer to use
+ *			in the read operation.
+ * @param region	The name of the fmap region to read, or NULL to
+ *			read the entire flash chip.
+ *
+ * @return 0 on success, or < 0 on error.
+ */
+int flashrom_host_read(struct buffer *buffer, const char *region);
+
+/**
+ * Write using flashrom from a buffer.
+ *
+ * @param buffer	The parameter that contains the buffer to use
+ *			in the write operation.
+ * @param regions	The name of the fmap region to write, or NULL to
+ *			write the entire flash chip.
+ *
+ * @return 0 on success, or < 0 on error.
+ */
+int flashrom_host_write(struct buffer *buffer, const char *region);