Merge pull request #2251 from particle-iot/bug/ch68808/low-level-input-output-slow-on-os-2-0-0-rc4

Always inline fastPinGetPinmap to speed pin sets

Author: avtolstoy

user/tests/wiring/no_fixture/fastpin.cpp

@@ -0,0 +1,68 @@
+
+#include "application.h"
+#include "unit-test/unit-test.h"
+
+
+
+test(FASTPIN_01_MaxDuration_PinSet) {
+    // Attempt pinSetFast and pinResetFast numerous times and check speed.
+    // Duration went from about 62 -> 24 ticks per set on Gen2 with this change list
+
+#if HAL_PLATFORM_GEN == 3
+    // expected max ticks of pinSetFast / pinResetFast on Gen3
+    const uint32_t MAX_DURATION_PINSET_TICKS = 61;
+#elif HAL_PLATFORM_GEN == 2
+    // expected max ticks of pinSetFast / pinResetFast on Gen2
+    const uint32_t MAX_DURATION_PINSET_TICKS = 24;
+#else
+#error "No gpio fastpin timing benchmark yet measured for this platform"
+#endif
+
+    const uint32_t NUM_ITERATIONS = 100;
+    uint32_t start, finish;
+
+    ATOMIC_BLOCK()  {
+        start = System.ticks();
+        for (uint32_t i = 0; i < NUM_ITERATIONS; i++) {
+            pinSetFast(D7);
+            //pinResetFast(D7);
+        }
+        finish = System.ticks();
+    }
+    uint32_t duration = finish - start;
+//    Serial.print("Set duration:");
+//    Serial.println(duration);
+    assertLessOrEqual(duration, NUM_ITERATIONS*MAX_DURATION_PINSET_TICKS);
+}
+
+test(FASTPIN_02_MaxDuration_PinReset) {
+    // Attempt pinResetFast numerous times and check speed.
+
+#if HAL_PLATFORM_GEN == 3
+    // expected max ticks of pinResetFast on Gen3
+    const uint32_t MAX_DURATION_PINRESET_TICKS = 60;
+#elif HAL_PLATFORM_GEN == 2
+    // expected max ticks of pinResetFast on Gen2
+    const uint32_t MAX_DURATION_PINRESET_TICKS = 25;
+#else
+#error "No gpio fastpin timing benchmark yet measured for this platform"
+#endif
+
+    const uint32_t NUM_ITERATIONS = 100;
+    uint32_t start, finish;
+
+    ATOMIC_BLOCK()  {
+        start = System.ticks();
+        for (uint32_t i = 0; i < NUM_ITERATIONS; i++) {
+            pinResetFast(D7);
+        }
+        finish = System.ticks();
+    }
+    uint32_t duration = finish - start;
+//    Serial.print("Reset duration:");
+//    Serial.println(duration);
+    assertLessOrEqual(duration, NUM_ITERATIONS*MAX_DURATION_PINRESET_TICKS);
+}
+
+
+

wiring/inc/fast_pin.h

@@ -32,8 +32,8 @@ extern "C" {
  * by @pkourany on PR: https://github.com/spark/firmware/pull/556 */
 #define USE_BIT_BAND 0
 
-inline const Hal_Pin_Info* fastPinGetPinmap() {
-    static Hal_Pin_Info* pinMap = HAL_Pin_Map();
+__attribute__((always_inline)) inline const Hal_Pin_Info* fastPinGetPinmap() {
+    static const Hal_Pin_Info* pinMap = HAL_Pin_Map();
     return pinMap;
 }