NFC: fix MFC timings (#2719)

* digital signal: add optimization
* nfc test: more restrict tests
* digital signal: build as separate library
* digital signal: remove unused flags, format sources
* digital signal: fix cflag name
* target: fix build for f18 target

Co-authored-by: あく <alleteam@gmail.com>

applications/debug/unit_tests/nfc/nfc_test.c

@@ -27,6 +27,12 @@ static const uint32_t nfc_test_file_version = 1;
 #define NFC_TEST_DATA_MAX_LEN 18
 #define NFC_TETS_TIMINGS_MAX_LEN 1350
 
+// Maximum allowed time for buffer preparation to fit 500us nt message timeout
+#define NFC_TEST_4_BYTE_BUILD_BUFFER_TIM_MAX (150)
+#define NFC_TEST_16_BYTE_BUILD_BUFFER_TIM_MAX (640)
+#define NFC_TEST_4_BYTE_BUILD_SIGNAL_TIM_MAX (110)
+#define NFC_TEST_16_BYTE_BUILD_SIGNAL_TIM_MAX (440)
+
 typedef struct {
     Storage* storage;
     NfcaSignal* signal;
@@ -89,13 +95,13 @@ static bool nfc_test_read_signal_from_file(const char* file_name) {
 
 static bool nfc_test_digital_signal_test_encode(
     const char* file_name,
-    uint32_t encode_max_time,
+    uint32_t build_signal_max_time_us,
+    uint32_t build_buffer_max_time_us,
     uint32_t timing_tolerance,
     uint32_t timings_sum_tolerance) {
     furi_assert(nfc_test);
 
     bool success = false;
-    uint32_t time = 0;
     uint32_t dut_timings_sum = 0;
     uint32_t ref_timings_sum = 0;
     uint8_t parity[10] = {};
@@ -109,17 +115,37 @@ static bool nfc_test_digital_signal_test_encode(
 
         // Encode signal
         FURI_CRITICAL_ENTER();
-        time = DWT->CYCCNT;
+        uint32_t time_start = DWT->CYCCNT;
+
         nfca_signal_encode(
             nfc_test->signal, nfc_test->test_data, nfc_test->test_data_len * 8, parity);
+
+        uint32_t time_signal =
+            (DWT->CYCCNT - time_start) / furi_hal_cortex_instructions_per_microsecond();
+
+        time_start = DWT->CYCCNT;
+
         digital_signal_prepare_arr(nfc_test->signal->tx_signal);
-        time = (DWT->CYCCNT - time) / furi_hal_cortex_instructions_per_microsecond();
+
+        uint32_t time_buffer =
+            (DWT->CYCCNT - time_start) / furi_hal_cortex_instructions_per_microsecond();
         FURI_CRITICAL_EXIT();
 
         // Check timings
-        if(time > encode_max_time) {
+        if(time_signal > build_signal_max_time_us) {
             FURI_LOG_E(
-                TAG, "Encoding time: %ld us while accepted value: %ld us", time, encode_max_time);
+                TAG,
+                "Build signal time: %ld us while accepted value: %ld us",
+                time_signal,
+                build_signal_max_time_us);
+            break;
+        }
+        if(time_buffer > build_buffer_max_time_us) {
+            FURI_LOG_E(
+                TAG,
+                "Build buffer time: %ld us while accepted value: %ld us",
+                time_buffer,
+                build_buffer_max_time_us);
             break;
         }
 
@@ -156,7 +182,16 @@ static bool nfc_test_digital_signal_test_encode(
             break;
         }
 
-        FURI_LOG_I(TAG, "Encoding time: %ld us. Acceptable time: %ld us", time, encode_max_time);
+        FURI_LOG_I(
+            TAG,
+            "Build signal time: %ld us. Acceptable time: %ld us",
+            time_signal,
+            build_signal_max_time_us);
+        FURI_LOG_I(
+            TAG,
+            "Build buffer time: %ld us. Acceptable time: %ld us",
+            time_buffer,
+            build_buffer_max_time_us);
         FURI_LOG_I(
             TAG,
             "Timings sum difference: %ld [1/64MHZ]. Acceptable difference: %ld [1/64MHz]",
@@ -171,11 +206,19 @@ static bool nfc_test_digital_signal_test_encode(
 MU_TEST(nfc_digital_signal_test) {
     mu_assert(
         nfc_test_digital_signal_test_encode(
-            NFC_TEST_RESOURCES_DIR NFC_TEST_SIGNAL_SHORT_FILE, 500, 1, 37),
+            NFC_TEST_RESOURCES_DIR NFC_TEST_SIGNAL_SHORT_FILE,
+            NFC_TEST_4_BYTE_BUILD_SIGNAL_TIM_MAX,
+            NFC_TEST_4_BYTE_BUILD_BUFFER_TIM_MAX,
+            1,
+            37),
         "NFC short digital signal test failed\r\n");
     mu_assert(
         nfc_test_digital_signal_test_encode(
-            NFC_TEST_RESOURCES_DIR NFC_TEST_SIGNAL_LONG_FILE, 2000, 1, 37),
+            NFC_TEST_RESOURCES_DIR NFC_TEST_SIGNAL_LONG_FILE,
+            NFC_TEST_16_BYTE_BUILD_SIGNAL_TIM_MAX,
+            NFC_TEST_16_BYTE_BUILD_BUFFER_TIM_MAX,
+            1,
+            37),
         "NFC long digital signal test failed\r\n");
 }
 

firmware/targets/f18/api_symbols.csv

@@ -1,5 +1,5 @@
 entry,status,name,type,params
-Version,+,28.1,,
+Version,+,28.2,,
 Header,+,applications/services/bt/bt_service/bt.h,,
 Header,+,applications/services/cli/cli.h,,
 Header,+,applications/services/cli/cli_vcp.h,,
@@ -80,6 +80,7 @@ Header,+,firmware/targets/furi_hal_include/furi_hal_usb_hid.h,,
 Header,+,firmware/targets/furi_hal_include/furi_hal_usb_hid_u2f.h,,
 Header,+,firmware/targets/furi_hal_include/furi_hal_version.h,,
 Header,+,firmware/targets/furi_hal_include/furi_hal_vibro.h,,
+Header,+,lib/digital_signal/digital_signal.h,,
 Header,+,lib/flipper_application/api_hashtable/api_hashtable.h,,
 Header,+,lib/flipper_application/api_hashtable/compilesort.hpp,,
 Header,+,lib/flipper_application/flipper_application.h,,
@@ -617,6 +618,24 @@ Function,+,dialog_message_set_text,void,"DialogMessage*, const char*, uint8_t, u
 Function,+,dialog_message_show,DialogMessageButton,"DialogsApp*, const DialogMessage*"
 Function,+,dialog_message_show_storage_error,void,"DialogsApp*, const char*"
 Function,-,difftime,double,"time_t, time_t"
+Function,-,digital_sequence_add,void,"DigitalSequence*, uint8_t"
+Function,-,digital_sequence_alloc,DigitalSequence*,"uint32_t, const GpioPin*"
+Function,-,digital_sequence_clear,void,DigitalSequence*
+Function,-,digital_sequence_free,void,DigitalSequence*
+Function,-,digital_sequence_send,_Bool,DigitalSequence*
+Function,-,digital_sequence_set_sendtime,void,"DigitalSequence*, uint32_t"
+Function,-,digital_sequence_set_signal,void,"DigitalSequence*, uint8_t, DigitalSignal*"
+Function,-,digital_sequence_timebase_correction,void,"DigitalSequence*, float"
+Function,-,digital_signal_add,void,"DigitalSignal*, uint32_t"
+Function,-,digital_signal_add_pulse,void,"DigitalSignal*, uint32_t, _Bool"
+Function,-,digital_signal_alloc,DigitalSignal*,uint32_t
+Function,-,digital_signal_append,_Bool,"DigitalSignal*, DigitalSignal*"
+Function,-,digital_signal_free,void,DigitalSignal*
+Function,-,digital_signal_get_edge,uint32_t,"DigitalSignal*, uint32_t"
+Function,-,digital_signal_get_edges_cnt,uint32_t,DigitalSignal*
+Function,-,digital_signal_get_start_level,_Bool,DigitalSignal*
+Function,-,digital_signal_prepare_arr,void,DigitalSignal*
+Function,-,digital_signal_send,void,"DigitalSignal*, const GpioPin*"
 Function,-,diprintf,int,"int, const char*, ..."
 Function,+,dir_walk_alloc,DirWalk*,Storage*
 Function,+,dir_walk_close,void,DirWalk*

firmware/targets/f7/api_symbols.csv

@@ -1,5 +1,5 @@
 entry,status,name,type,params
-Version,+,28.1,,
+Version,+,28.2,,
 Header,+,applications/services/bt/bt_service/bt.h,,
 Header,+,applications/services/cli/cli.h,,
 Header,+,applications/services/cli/cli_vcp.h,,
@@ -86,6 +86,7 @@ Header,+,firmware/targets/furi_hal_include/furi_hal_usb_hid.h,,
 Header,+,firmware/targets/furi_hal_include/furi_hal_usb_hid_u2f.h,,
 Header,+,firmware/targets/furi_hal_include/furi_hal_version.h,,
 Header,+,firmware/targets/furi_hal_include/furi_hal_vibro.h,,
+Header,+,lib/digital_signal/digital_signal.h,,
 Header,+,lib/flipper_application/api_hashtable/api_hashtable.h,,
 Header,+,lib/flipper_application/api_hashtable/compilesort.hpp,,
 Header,+,lib/flipper_application/flipper_application.h,,

firmware/targets/f7/target.json

@@ -28,6 +28,7 @@
         "flipperformat",
         "toolbox",
         "nfc",
+        "digital_signal",
         "pulse_reader",
         "microtar",
         "usb_stm32",

lib/ReadMe.md

@@ -27,6 +27,7 @@
 - `nfc`                 - NFC library, used by NFC application
 - `one_wire`            - OneWire library, used by iButton application
 - `print`               - Tiny printf implementation
+- `digital_signal`      - Digital Signal library used by NFC for software implemented protocols
 - `pulse_reader`        - Pulse Reader library used by NFC for software implemented protocols
 - `qrcode`              - QR-Code library
 - `stm32wb_cmsis`       - STM32WB series CMSIS headers, extends CMSIS Core

lib/SConscript

@@ -15,7 +15,6 @@ env.Append(
         Dir("u8g2"),
         Dir("update_util"),
         Dir("print"),
-        Dir("pulse_reader"),
     ],
 )
 
@@ -95,6 +94,7 @@ libs = env.BuildModules(
         "mbedtls",
         "subghz",
         "nfc",
+        "digital_signal",
         "pulse_reader",
         "appframe",
         "misc",

lib/digital_signal/SConscript

@@ -0,0 +1,20 @@
+Import("env")
+
+env.Append(
+    CPPPATH=[
+        "#/lib/digital_signal",
+    ],
+    SDK_HEADERS=[
+        File("digital_signal.h"),
+    ],
+)
+
+libenv = env.Clone(FW_LIB_NAME="digital_signal")
+libenv.ApplyLibFlags()
+libenv.Append(CCFLAGS=["-O3", "-funroll-loops", "-Ofast"])
+
+sources = libenv.GlobRecursive("*.c*")
+
+lib = libenv.StaticLibrary("${FW_LIB_NAME}", sources)
+libenv.Install("${LIB_DIST_DIR}", lib)
+Return("lib")

lib/digital_signal/digital_signal.c

@@ -212,8 +212,7 @@ void digital_signal_prepare_arr(DigitalSignal* signal) {
     internals->reload_reg_entries = 0;
 
     for(size_t pos = 0; pos < signal->edge_cnt; pos++) {
-        uint32_t edge_scaled = (internals->factor * signal->edge_timings[pos]) / (1024 * 1024);
+        uint32_t pulse_duration = signal->edge_timings[pos] + internals->reload_reg_remainder;
-        uint32_t pulse_duration = edge_scaled + internals->reload_reg_remainder;
         if(pulse_duration < 10 || pulse_duration > 10000000) {
             FURI_LOG_D(
                 TAG,

lib/misc.scons

@@ -4,7 +4,6 @@ Import("env")
 
 env.Append(
     CPPPATH=[
-        "#/lib/digital_signal",
         "#/lib/fnv1a_hash",
         "#/lib/heatshrink",
         "#/lib/micro-ecc",
@@ -26,7 +25,6 @@ libenv.ApplyLibFlags()
 sources = []
 
 libs_recurse = [
-    "digital_signal",
     "micro-ecc",
     "u8g2",
     "update_util",