fpsensor: Build fpsensor source file with C++

This change removes abs() since this change also makes the fingerprint
firmware link against the toolchain's C standard library, which already
provides an implementation. Note that abs() is not actually used by the
FPC matching algorithm even though it links against it.

BRANCH=none
BUG=b:236025198, b:234181908
TEST=On dragonclaw v0.2 with servo_micro and J-Trace attached:
     ./util/flash_jlink.py -b bloonchipper -i ./build/bloonchipper/ec.bin
     > fpenroll
     > fpmatch
TEST=On dragonclaw v0.2 with servo_micro and J-Trace attached:
     ./test/run_device_tests.py --board bloonchipper
     Test "aes": PASSED
     Test "cec": PASSED
     Test "cortexm_fpu": PASSED
     Test "crc": PASSED
     Test "flash_physical": PASSED
     Test "flash_write_protect": PASSED
     Test "fpsensor_hw": PASSED
     Test "fpsensor_spi_ro": PASSED
     Test "fpsensor_spi_rw": PASSED
     Test "fpsensor_uart_ro": PASSED
     Test "fpsensor_uart_rw": PASSED
     Test "mpu_ro": PASSED
     Test "mpu_rw": PASSED
     Test "mutex": PASSED
     Test "pingpong": PASSED
     Test "printf": PASSED
     Test "queue": PASSED
     Test "rollback_region0": PASSED
     Test "rollback_region1": PASSED
     Test "rollback_entropy": PASSED
     Test "rtc": PASSED
     Test "sha256": PASSED
     Test "sha256_unrolled": PASSED
     Test "static_if": PASSED
     Test "stdlib": PASSED
     Test "system_is_locked_wp_on": PASSED
     Test "system_is_locked_wp_off": PASSED
     Test "timer_dos": PASSED
     Test "utils": PASSED
     Test "utils_str": PASSED
     Test "stm32f_rtc": PASSED
     Test "panic_data_bloonchipper_v2.0.4277": PASSED
     Test "panic_data_bloonchipper_v2.0.5938": PASSED
TEST=On icetower v0.1 with servo_micro and J-Trace attached:
     ./util/flash_jlink.py -b dartmonkey -i ./build/dartmonkey/ec.bin
     > fpenroll
     > fpmatch
TEST=On icetower v0.1 with servo_micro and J-Trace attached:
     ./test/run_device_tests.py --board dartmonkey
     Test "aes": PASSED
     Test "cec": PASSED
     Test "cortexm_fpu": PASSED
     Test "crc": PASSED
     Test "flash_physical": PASSED
     Test "flash_write_protect": PASSED
     Test "fpsensor_hw": PASSED
     Test "fpsensor_spi_ro": PASSED
     Test "fpsensor_spi_rw": PASSED
     Test "fpsensor_uart_ro": PASSED
     Test "fpsensor_uart_rw": PASSED
     Test "mpu_ro": PASSED
     Test "mpu_rw": PASSED
     Test "mutex": PASSED
     Test "pingpong": PASSED
     Test "printf": PASSED
     Test "queue": PASSED
     Test "rollback_region0": PASSED
     Test "rollback_region1": PASSED
     Test "rollback_entropy": PASSED
     Test "rtc": PASSED
     Test "sha256": PASSED
     Test "sha256_unrolled": PASSED
     Test "static_if": PASSED
     Test "stdlib": PASSED
     Test "system_is_locked_wp_on": PASSED
     Test "system_is_locked_wp_off": PASSED
     Test "timer_dos": PASSED
     Test "utils": PASSED
     Test "utils_str": PASSED
     Test "panic_data_dartmonkey_v2.0.2887": PASSED
     Test "panic_data_nocturne_fp_v2.2.64": PASSED
     Test "panic_data_nami_fp_v2.2.144": PASSED

Signed-off-by: Tom Hughes <tomhughes@chromium.org>
Change-Id: Iab0de3355cbe928c7b7132263ea6d32c1e9f3a6e
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3551682
Reviewed-by: Bobby Casey <bobbycasey@google.com>
Code-Coverage: Zoss <zoss-cl-coverage@prod.google.com>
Reviewed-by: Andrea Grandi <agrandi@google.com>

1 files changed, 20 insertions, 9 deletions

diff --git a/common/fpsensor/fpsensor.c b/common/fpsensor/fpsensor.cc
index 3e97741705..a4a6eefaa9 100644
--- a/common/fpsensor/fpsensor.c
+++ b/common/fpsensor/fpsensor.cc
@@ -3,6 +3,9 @@
  * found in the LICENSE file.
  */
 
+#include "compile_time_macros.h"
+
+extern "C" {
 #include "atomic.h"
 #include "clock.h"
 #include "common.h"
@@ -25,6 +28,7 @@
 #include "trng.h"
 #include "util.h"
 #include "watchdog.h"
+}
 
 #if !defined(CONFIG_RNG)
 #error "fpsensor requires RNG"
@@ -231,7 +235,7 @@ static void fp_process_finger(void)
 }
 #endif /* HAVE_FP_PRIVATE_DRIVER */
 
-void fp_task(void)
+extern "C" void fp_task(void)
 {
 	int timeout_us = -1;
 
@@ -336,8 +340,9 @@ void fp_task(void)
 
 static enum ec_status fp_command_passthru(struct host_cmd_handler_args *args)
 {
-	const struct ec_params_fp_passthru *params = args->params;
-	void *out = args->response;
+	const struct ec_params_fp_passthru *params =
+		static_cast<const ec_params_fp_passthru *>(args->params);
+	uint8_t *out = static_cast<uint8_t *>(args->response);
 	int rc;
 	enum ec_status ret = EC_RES_SUCCESS;
 
@@ -369,7 +374,8 @@ DECLARE_HOST_COMMAND(EC_CMD_FP_PASSTHRU, fp_command_passthru, EC_VER_MASK(0));
 
 static enum ec_status fp_command_info(struct host_cmd_handler_args *args)
 {
-	struct ec_response_fp_info *r = args->response;
+	struct ec_response_fp_info *r =
+		static_cast<ec_response_fp_info *>(args->response);
 
 #ifdef HAVE_FP_PRIVATE_DRIVER
 	if (fp_sensor_get_info(r) < 0)
@@ -409,7 +415,8 @@ int validate_fp_buffer_offset(const uint32_t buffer_size, const uint32_t offset,
 
 static enum ec_status fp_command_frame(struct host_cmd_handler_args *args)
 {
-	const struct ec_params_fp_frame *params = args->params;
+	const struct ec_params_fp_frame *params =
+		static_cast<const struct ec_params_fp_frame *>(args->params);
 	void *out = args->response;
 	uint32_t idx = FP_FRAME_GET_BUFFER_INDEX(params->offset);
 	uint32_t offset = params->offset & FP_FRAME_OFFSET_MASK;
@@ -473,7 +480,8 @@ static enum ec_status fp_command_frame(struct host_cmd_handler_args *args)
 		 * The beginning of the buffer contains nonce, encryption_salt
 		 * and tag.
 		 */
-		enc_info = (void *)fp_enc_buffer;
+		enc_info = (struct ec_fp_template_encryption_metadata
+				    *)(fp_enc_buffer);
 		enc_info->struct_version = FP_TEMPLATE_FORMAT_VERSION;
 		trng_init();
 		trng_rand_bytes(enc_info->nonce, FP_CONTEXT_NONCE_BYTES);
@@ -534,7 +542,8 @@ DECLARE_HOST_COMMAND(EC_CMD_FP_FRAME, fp_command_frame, EC_VER_MASK(0));
 
 static enum ec_status fp_command_stats(struct host_cmd_handler_args *args)
 {
-	struct ec_response_fp_stats *r = args->response;
+	struct ec_response_fp_stats *r =
+		static_cast<struct ec_response_fp_stats *>(args->response);
 
 	r->capture_time_us = capture_time_us;
 	r->matching_time_us = matching_time_us;
@@ -575,7 +584,8 @@ validate_template_format(struct ec_fp_template_encryption_metadata *enc_info)
 
 static enum ec_status fp_command_template(struct host_cmd_handler_args *args)
 {
-	const struct ec_params_fp_template *params = args->params;
+	const struct ec_params_fp_template *params =
+		static_cast<const struct ec_params_fp_template *>(args->params);
 	uint32_t size = params->size & ~FP_TEMPLATE_COMMIT;
 	int xfer_complete = params->size & FP_TEMPLATE_COMMIT;
 	uint32_t offset = params->offset;
@@ -614,7 +624,8 @@ static enum ec_status fp_command_template(struct host_cmd_handler_args *args)
 		 * The beginning of the buffer contains nonce, encryption_salt
 		 * and tag.
 		 */
-		enc_info = (void *)fp_enc_buffer;
+		enc_info = (struct ec_fp_template_encryption_metadata *)
+			fp_enc_buffer;
 		ret = validate_template_format(enc_info);
 		if (ret != EC_RES_SUCCESS) {
 			CPRINTS("fgr%d: Template format not supported", idx);