From 5b0eaac30badd5225a944accb6491f8015534a46 Mon Sep 17 00:00:00 2001
From: Max Prokhorov <prokhorov.max@outlook.com>
Date: Mon, 29 Apr 2019 10:28:47 +0300
Subject: [PATCH] ESP8266 / ESP32: Place ISR in IRAM

---
 Encoder.cpp |   2 -
 Encoder.h   | 553 ++++++++++++++++++++++++++--------------------------
 2 files changed, 281 insertions(+), 274 deletions(-)

diff --git a/Encoder.cpp b/Encoder.cpp
index 6911b4f..b2d33d6 100644
--- a/Encoder.cpp
+++ b/Encoder.cpp
@@ -5,6 +5,4 @@
 // configure options with #define (before they include it), and
 // to facilitate some crafty optimizations!
 
-Encoder_internal_state_t * Encoder::interruptArgs[];
-
 
diff --git a/Encoder.h b/Encoder.h
index 6e0a2c3..147f932 100644
--- a/Encoder.h
+++ b/Encoder.h
@@ -51,6 +51,14 @@
 #define ENCODER_ARGLIST_SIZE 0
 #endif
 
+// We need to manually place interrupt handlers in RAM for these platforms
+#if defined(ESP8266) || defined(ESP32)
+#ifndef IRAM_ATTR
+#define IRAM_ATTR ICACHE_RAM_ATTR
+#endif
+#else
+#define IRAM_ATTR
+#endif
 
 
 // All the data needed by interrupts is consolidated into this ugly struct
@@ -66,92 +74,9 @@ typedef struct {
 	int32_t                position;
 } Encoder_internal_state_t;
 
-class Encoder
-{
-public:
-	Encoder(uint8_t pin1, uint8_t pin2) {
-		#ifdef INPUT_PULLUP
-		pinMode(pin1, INPUT_PULLUP);
-		pinMode(pin2, INPUT_PULLUP);
-		#else
-		pinMode(pin1, INPUT);
-		digitalWrite(pin1, HIGH);
-		pinMode(pin2, INPUT);
-		digitalWrite(pin2, HIGH);
-		#endif
-		encoder.pin1_register = PIN_TO_BASEREG(pin1);
-		encoder.pin1_bitmask = PIN_TO_BITMASK(pin1);
-		encoder.pin2_register = PIN_TO_BASEREG(pin2);
-		encoder.pin2_bitmask = PIN_TO_BITMASK(pin2);
-		encoder.position = 0;
-		// allow time for a passive R-C filter to charge
-		// through the pullup resistors, before reading
-		// the initial state
-		delayMicroseconds(2000);
-		uint8_t s = 0;
-		if (DIRECT_PIN_READ(encoder.pin1_register, encoder.pin1_bitmask)) s |= 1;
-		if (DIRECT_PIN_READ(encoder.pin2_register, encoder.pin2_bitmask)) s |= 2;
-		encoder.state = s;
-#ifdef ENCODER_USE_INTERRUPTS
-		interrupts_in_use = attach_interrupt(pin1, &encoder);
-		interrupts_in_use += attach_interrupt(pin2, &encoder);
-#endif
-		//update_finishup();  // to force linker to include the code (does not work)
-	}
+static Encoder_internal_state_t * interruptArgs[ENCODER_ARGLIST_SIZE];
 
 
-#ifdef ENCODER_USE_INTERRUPTS
-	inline int32_t read() {
-		if (interrupts_in_use < 2) {
-			noInterrupts();
-			update(&encoder);
-		} else {
-			noInterrupts();
-		}
-		int32_t ret = encoder.position;
-		interrupts();
-		return ret;
-	}
-	inline int32_t readAndReset() {
-		if (interrupts_in_use < 2) {
-			noInterrupts();
-			update(&encoder);
-		} else {
-			noInterrupts();
-		}
-		int32_t ret = encoder.position;
-		encoder.position = 0;
-		interrupts();
-		return ret;
-	}
-	inline void write(int32_t p) {
-		noInterrupts();
-		encoder.position = p;
-		interrupts();
-	}
-#else
-	inline int32_t read() {
-		update(&encoder);
-		return encoder.position;
-	}
-	inline int32_t readAndReset() {
-		update(&encoder);
-		int32_t ret = encoder.position;
-		encoder.position = 0;
-		return ret;
-	}
-	inline void write(int32_t p) {
-		encoder.position = p;
-	}
-#endif
-private:
-	Encoder_internal_state_t encoder;
-#ifdef ENCODER_USE_INTERRUPTS
-	uint8_t interrupts_in_use;
-#endif
-public:
-	static Encoder_internal_state_t * interruptArgs[ENCODER_ARGLIST_SIZE];
-
 //                           _______         _______       
 //               Pin1 ______|       |_______|       |______ Pin1
 // negative <---         _______         _______         __      --> positive
@@ -199,11 +124,10 @@ class Encoder
 	}
 */
 
-public:
-	// update() is not meant to be called from outside Encoder,
-	// but it is public to allow static interrupt routines.
-	// DO NOT call update() directly from sketches.
-	static void update(Encoder_internal_state_t *arg) {
+// update() is not meant to be called from outside Encoder,
+// but it is public to allow static interrupt routines.
+// DO NOT call update() directly from sketches.
+static void IRAM_ATTR update(Encoder_internal_state_t *arg) {
 #if defined(__AVR__)
 		// The compiler believes this is just 1 line of code, so
 		// it will inline this function into each interrupt
@@ -311,6 +235,274 @@ class Encoder
 		}
 #endif
 	}
+
+#if defined(ENCODER_USE_INTERRUPTS) && !defined(ENCODER_OPTIMIZE_INTERRUPTS)
+	#ifdef CORE_INT0_PIN
+	static void IRAM_ATTR isr0(void) { update(interruptArgs[0]); }
+	#endif
+	#ifdef CORE_INT1_PIN
+	static void IRAM_ATTR isr1(void) { update(interruptArgs[1]); }
+	#endif
+	#ifdef CORE_INT2_PIN
+	static void IRAM_ATTR isr2(void) { update(interruptArgs[2]); }
+	#endif
+	#ifdef CORE_INT3_PIN
+	static void IRAM_ATTR isr3(void) { update(interruptArgs[3]); }
+	#endif
+	#ifdef CORE_INT4_PIN
+	static void IRAM_ATTR isr4(void) { update(interruptArgs[4]); }
+	#endif
+	#ifdef CORE_INT5_PIN
+	static void IRAM_ATTR isr5(void) { update(interruptArgs[5]); }
+	#endif
+	#ifdef CORE_INT6_PIN
+	static void IRAM_ATTR isr6(void) { update(interruptArgs[6]); }
+	#endif
+	#ifdef CORE_INT7_PIN
+	static void IRAM_ATTR isr7(void) { update(interruptArgs[7]); }
+	#endif
+	#ifdef CORE_INT8_PIN
+	static void IRAM_ATTR isr8(void) { update(interruptArgs[8]); }
+	#endif
+	#ifdef CORE_INT9_PIN
+	static void IRAM_ATTR isr9(void) { update(interruptArgs[9]); }
+	#endif
+	#ifdef CORE_INT10_PIN
+	static void IRAM_ATTR isr10(void) { update(interruptArgs[10]); }
+	#endif
+	#ifdef CORE_INT11_PIN
+	static void IRAM_ATTR isr11(void) { update(interruptArgs[11]); }
+	#endif
+	#ifdef CORE_INT12_PIN
+	static void IRAM_ATTR isr12(void) { update(interruptArgs[12]); }
+	#endif
+	#ifdef CORE_INT13_PIN
+	static void IRAM_ATTR isr13(void) { update(interruptArgs[13]); }
+	#endif
+	#ifdef CORE_INT14_PIN
+	static void IRAM_ATTR isr14(void) { update(interruptArgs[14]); }
+	#endif
+	#ifdef CORE_INT15_PIN
+	static void IRAM_ATTR isr15(void) { update(interruptArgs[15]); }
+	#endif
+	#ifdef CORE_INT16_PIN
+	static void IRAM_ATTR isr16(void) { update(interruptArgs[16]); }
+	#endif
+	#ifdef CORE_INT17_PIN
+	static void IRAM_ATTR isr17(void) { update(interruptArgs[17]); }
+	#endif
+	#ifdef CORE_INT18_PIN
+	static void IRAM_ATTR isr18(void) { update(interruptArgs[18]); }
+	#endif
+	#ifdef CORE_INT19_PIN
+	static void IRAM_ATTR isr19(void) { update(interruptArgs[19]); }
+	#endif
+	#ifdef CORE_INT20_PIN
+	static void IRAM_ATTR isr20(void) { update(interruptArgs[20]); }
+	#endif
+	#ifdef CORE_INT21_PIN
+	static void IRAM_ATTR isr21(void) { update(interruptArgs[21]); }
+	#endif
+	#ifdef CORE_INT22_PIN
+	static void IRAM_ATTR isr22(void) { update(interruptArgs[22]); }
+	#endif
+	#ifdef CORE_INT23_PIN
+	static void IRAM_ATTR isr23(void) { update(interruptArgs[23]); }
+	#endif
+	#ifdef CORE_INT24_PIN
+	static void IRAM_ATTR isr24(void) { update(interruptArgs[24]); }
+	#endif
+	#ifdef CORE_INT25_PIN
+	static void IRAM_ATTR isr25(void) { update(interruptArgs[25]); }
+	#endif
+	#ifdef CORE_INT26_PIN
+	static void IRAM_ATTR isr26(void) { update(interruptArgs[26]); }
+	#endif
+	#ifdef CORE_INT27_PIN
+	static void IRAM_ATTR isr27(void) { update(interruptArgs[27]); }
+	#endif
+	#ifdef CORE_INT28_PIN
+	static void IRAM_ATTR isr28(void) { update(interruptArgs[28]); }
+	#endif
+	#ifdef CORE_INT29_PIN
+	static void IRAM_ATTR isr29(void) { update(interruptArgs[29]); }
+	#endif
+	#ifdef CORE_INT30_PIN
+	static void IRAM_ATTR isr30(void) { update(interruptArgs[30]); }
+	#endif
+	#ifdef CORE_INT31_PIN
+	static void IRAM_ATTR isr31(void) { update(interruptArgs[31]); }
+	#endif
+	#ifdef CORE_INT32_PIN
+	static void IRAM_ATTR isr32(void) { update(interruptArgs[32]); }
+	#endif
+	#ifdef CORE_INT33_PIN
+	static void IRAM_ATTR isr33(void) { update(interruptArgs[33]); }
+	#endif
+	#ifdef CORE_INT34_PIN
+	static void IRAM_ATTR isr34(void) { update(interruptArgs[34]); }
+	#endif
+	#ifdef CORE_INT35_PIN
+	static void IRAM_ATTR isr35(void) { update(interruptArgs[35]); }
+	#endif
+	#ifdef CORE_INT36_PIN
+	static void IRAM_ATTR isr36(void) { update(interruptArgs[36]); }
+	#endif
+	#ifdef CORE_INT37_PIN
+	static void IRAM_ATTR isr37(void) { update(interruptArgs[37]); }
+	#endif
+	#ifdef CORE_INT38_PIN
+	static void IRAM_ATTR isr38(void) { update(interruptArgs[38]); }
+	#endif
+	#ifdef CORE_INT39_PIN
+	static void IRAM_ATTR isr39(void) { update(interruptArgs[39]); }
+	#endif
+	#ifdef CORE_INT40_PIN
+	static void IRAM_ATTR isr40(void) { update(interruptArgs[40]); }
+	#endif
+	#ifdef CORE_INT41_PIN
+	static void IRAM_ATTR isr41(void) { update(interruptArgs[41]); }
+	#endif
+	#ifdef CORE_INT42_PIN
+	static void IRAM_ATTR isr42(void) { update(interruptArgs[42]); }
+	#endif
+	#ifdef CORE_INT43_PIN
+	static void IRAM_ATTR isr43(void) { update(interruptArgs[43]); }
+	#endif
+	#ifdef CORE_INT44_PIN
+	static void IRAM_ATTR isr44(void) { update(interruptArgs[44]); }
+	#endif
+	#ifdef CORE_INT45_PIN
+	static void IRAM_ATTR isr45(void) { update(interruptArgs[45]); }
+	#endif
+	#ifdef CORE_INT46_PIN
+	static void IRAM_ATTR isr46(void) { update(interruptArgs[46]); }
+	#endif
+	#ifdef CORE_INT47_PIN
+	static void IRAM_ATTR isr47(void) { update(interruptArgs[47]); }
+	#endif
+	#ifdef CORE_INT48_PIN
+	static void IRAM_ATTR isr48(void) { update(interruptArgs[48]); }
+	#endif
+	#ifdef CORE_INT49_PIN
+	static void IRAM_ATTR isr49(void) { update(interruptArgs[49]); }
+	#endif
+	#ifdef CORE_INT50_PIN
+	static void IRAM_ATTR isr50(void) { update(interruptArgs[50]); }
+	#endif
+	#ifdef CORE_INT51_PIN
+	static void IRAM_ATTR isr51(void) { update(interruptArgs[51]); }
+	#endif
+	#ifdef CORE_INT52_PIN
+	static void IRAM_ATTR isr52(void) { update(interruptArgs[52]); }
+	#endif
+	#ifdef CORE_INT53_PIN
+	static void IRAM_ATTR isr53(void) { update(interruptArgs[53]); }
+	#endif
+	#ifdef CORE_INT54_PIN
+	static void IRAM_ATTR isr54(void) { update(interruptArgs[54]); }
+	#endif
+	#ifdef CORE_INT55_PIN
+	static void IRAM_ATTR isr55(void) { update(interruptArgs[55]); }
+	#endif
+	#ifdef CORE_INT56_PIN
+	static void IRAM_ATTR isr56(void) { update(interruptArgs[56]); }
+	#endif
+	#ifdef CORE_INT57_PIN
+	static void IRAM_ATTR isr57(void) { update(interruptArgs[57]); }
+	#endif
+	#ifdef CORE_INT58_PIN
+	static void IRAM_ATTR isr58(void) { update(interruptArgs[58]); }
+	#endif
+	#ifdef CORE_INT59_PIN
+	static void IRAM_ATTR isr59(void) { update(interruptArgs[59]); }
+	#endif
+#endif
+
+class Encoder
+{
+public:
+	Encoder(uint8_t pin1, uint8_t pin2) {
+		#ifdef INPUT_PULLUP
+		pinMode(pin1, INPUT_PULLUP);
+		pinMode(pin2, INPUT_PULLUP);
+		#else
+		pinMode(pin1, INPUT);
+		digitalWrite(pin1, HIGH);
+		pinMode(pin2, INPUT);
+		digitalWrite(pin2, HIGH);
+		#endif
+		encoder.pin1_register = PIN_TO_BASEREG(pin1);
+		encoder.pin1_bitmask = PIN_TO_BITMASK(pin1);
+		encoder.pin2_register = PIN_TO_BASEREG(pin2);
+		encoder.pin2_bitmask = PIN_TO_BITMASK(pin2);
+		encoder.position = 0;
+		// allow time for a passive R-C filter to charge
+		// through the pullup resistors, before reading
+		// the initial state
+		delayMicroseconds(2000);
+		uint8_t s = 0;
+		if (DIRECT_PIN_READ(encoder.pin1_register, encoder.pin1_bitmask)) s |= 1;
+		if (DIRECT_PIN_READ(encoder.pin2_register, encoder.pin2_bitmask)) s |= 2;
+		encoder.state = s;
+#ifdef ENCODER_USE_INTERRUPTS
+		interrupts_in_use = attach_interrupt(pin1, &encoder);
+		interrupts_in_use += attach_interrupt(pin2, &encoder);
+#endif
+		//update_finishup();  // to force linker to include the code (does not work)
+	}
+
+
+#ifdef ENCODER_USE_INTERRUPTS
+	inline int32_t read() {
+		if (interrupts_in_use < 2) {
+			noInterrupts();
+			update(&encoder);
+		} else {
+			noInterrupts();
+		}
+		int32_t ret = encoder.position;
+		interrupts();
+		return ret;
+	}
+	inline int32_t readAndReset() {
+		if (interrupts_in_use < 2) {
+			noInterrupts();
+			update(&encoder);
+		} else {
+			noInterrupts();
+		}
+		int32_t ret = encoder.position;
+		encoder.position = 0;
+		interrupts();
+		return ret;
+	}
+	inline void write(int32_t p) {
+		noInterrupts();
+		encoder.position = p;
+		interrupts();
+	}
+#else
+	inline int32_t read() {
+		update(&encoder);
+		return encoder.position;
+	}
+	inline int32_t readAndReset() {
+		update(&encoder);
+		int32_t ret = encoder.position;
+		encoder.position = 0;
+		return ret;
+	}
+	inline void write(int32_t p) {
+		encoder.position = p;
+	}
+#endif
+private:
+	Encoder_internal_state_t encoder;
+#ifdef ENCODER_USE_INTERRUPTS
+	uint8_t interrupts_in_use;
+#endif
+
 private:
 /*
 #if defined(__AVR__)
@@ -746,189 +938,6 @@ class Encoder
 	}
 #endif // ENCODER_USE_INTERRUPTS
 
-
-#if defined(ENCODER_USE_INTERRUPTS) && !defined(ENCODER_OPTIMIZE_INTERRUPTS)
-	#ifdef CORE_INT0_PIN
-	static void isr0(void) { update(interruptArgs[0]); }
-	#endif
-	#ifdef CORE_INT1_PIN
-	static void isr1(void) { update(interruptArgs[1]); }
-	#endif
-	#ifdef CORE_INT2_PIN
-	static void isr2(void) { update(interruptArgs[2]); }
-	#endif
-	#ifdef CORE_INT3_PIN
-	static void isr3(void) { update(interruptArgs[3]); }
-	#endif
-	#ifdef CORE_INT4_PIN
-	static void isr4(void) { update(interruptArgs[4]); }
-	#endif
-	#ifdef CORE_INT5_PIN
-	static void isr5(void) { update(interruptArgs[5]); }
-	#endif
-	#ifdef CORE_INT6_PIN
-	static void isr6(void) { update(interruptArgs[6]); }
-	#endif
-	#ifdef CORE_INT7_PIN
-	static void isr7(void) { update(interruptArgs[7]); }
-	#endif
-	#ifdef CORE_INT8_PIN
-	static void isr8(void) { update(interruptArgs[8]); }
-	#endif
-	#ifdef CORE_INT9_PIN
-	static void isr9(void) { update(interruptArgs[9]); }
-	#endif
-	#ifdef CORE_INT10_PIN
-	static void isr10(void) { update(interruptArgs[10]); }
-	#endif
-	#ifdef CORE_INT11_PIN
-	static void isr11(void) { update(interruptArgs[11]); }
-	#endif
-	#ifdef CORE_INT12_PIN
-	static void isr12(void) { update(interruptArgs[12]); }
-	#endif
-	#ifdef CORE_INT13_PIN
-	static void isr13(void) { update(interruptArgs[13]); }
-	#endif
-	#ifdef CORE_INT14_PIN
-	static void isr14(void) { update(interruptArgs[14]); }
-	#endif
-	#ifdef CORE_INT15_PIN
-	static void isr15(void) { update(interruptArgs[15]); }
-	#endif
-	#ifdef CORE_INT16_PIN
-	static void isr16(void) { update(interruptArgs[16]); }
-	#endif
-	#ifdef CORE_INT17_PIN
-	static void isr17(void) { update(interruptArgs[17]); }
-	#endif
-	#ifdef CORE_INT18_PIN
-	static void isr18(void) { update(interruptArgs[18]); }
-	#endif
-	#ifdef CORE_INT19_PIN
-	static void isr19(void) { update(interruptArgs[19]); }
-	#endif
-	#ifdef CORE_INT20_PIN
-	static void isr20(void) { update(interruptArgs[20]); }
-	#endif
-	#ifdef CORE_INT21_PIN
-	static void isr21(void) { update(interruptArgs[21]); }
-	#endif
-	#ifdef CORE_INT22_PIN
-	static void isr22(void) { update(interruptArgs[22]); }
-	#endif
-	#ifdef CORE_INT23_PIN
-	static void isr23(void) { update(interruptArgs[23]); }
-	#endif
-	#ifdef CORE_INT24_PIN
-	static void isr24(void) { update(interruptArgs[24]); }
-	#endif
-	#ifdef CORE_INT25_PIN
-	static void isr25(void) { update(interruptArgs[25]); }
-	#endif
-	#ifdef CORE_INT26_PIN
-	static void isr26(void) { update(interruptArgs[26]); }
-	#endif
-	#ifdef CORE_INT27_PIN
-	static void isr27(void) { update(interruptArgs[27]); }
-	#endif
-	#ifdef CORE_INT28_PIN
-	static void isr28(void) { update(interruptArgs[28]); }
-	#endif
-	#ifdef CORE_INT29_PIN
-	static void isr29(void) { update(interruptArgs[29]); }
-	#endif
-	#ifdef CORE_INT30_PIN
-	static void isr30(void) { update(interruptArgs[30]); }
-	#endif
-	#ifdef CORE_INT31_PIN
-	static void isr31(void) { update(interruptArgs[31]); }
-	#endif
-	#ifdef CORE_INT32_PIN
-	static void isr32(void) { update(interruptArgs[32]); }
-	#endif
-	#ifdef CORE_INT33_PIN
-	static void isr33(void) { update(interruptArgs[33]); }
-	#endif
-	#ifdef CORE_INT34_PIN
-	static void isr34(void) { update(interruptArgs[34]); }
-	#endif
-	#ifdef CORE_INT35_PIN
-	static void isr35(void) { update(interruptArgs[35]); }
-	#endif
-	#ifdef CORE_INT36_PIN
-	static void isr36(void) { update(interruptArgs[36]); }
-	#endif
-	#ifdef CORE_INT37_PIN
-	static void isr37(void) { update(interruptArgs[37]); }
-	#endif
-	#ifdef CORE_INT38_PIN
-	static void isr38(void) { update(interruptArgs[38]); }
-	#endif
-	#ifdef CORE_INT39_PIN
-	static void isr39(void) { update(interruptArgs[39]); }
-	#endif
-	#ifdef CORE_INT40_PIN
-	static void isr40(void) { update(interruptArgs[40]); }
-	#endif
-	#ifdef CORE_INT41_PIN
-	static void isr41(void) { update(interruptArgs[41]); }
-	#endif
-	#ifdef CORE_INT42_PIN
-	static void isr42(void) { update(interruptArgs[42]); }
-	#endif
-	#ifdef CORE_INT43_PIN
-	static void isr43(void) { update(interruptArgs[43]); }
-	#endif
-	#ifdef CORE_INT44_PIN
-	static void isr44(void) { update(interruptArgs[44]); }
-	#endif
-	#ifdef CORE_INT45_PIN
-	static void isr45(void) { update(interruptArgs[45]); }
-	#endif
-	#ifdef CORE_INT46_PIN
-	static void isr46(void) { update(interruptArgs[46]); }
-	#endif
-	#ifdef CORE_INT47_PIN
-	static void isr47(void) { update(interruptArgs[47]); }
-	#endif
-	#ifdef CORE_INT48_PIN
-	static void isr48(void) { update(interruptArgs[48]); }
-	#endif
-	#ifdef CORE_INT49_PIN
-	static void isr49(void) { update(interruptArgs[49]); }
-	#endif
-	#ifdef CORE_INT50_PIN
-	static void isr50(void) { update(interruptArgs[50]); }
-	#endif
-	#ifdef CORE_INT51_PIN
-	static void isr51(void) { update(interruptArgs[51]); }
-	#endif
-	#ifdef CORE_INT52_PIN
-	static void isr52(void) { update(interruptArgs[52]); }
-	#endif
-	#ifdef CORE_INT53_PIN
-	static void isr53(void) { update(interruptArgs[53]); }
-	#endif
-	#ifdef CORE_INT54_PIN
-	static void isr54(void) { update(interruptArgs[54]); }
-	#endif
-	#ifdef CORE_INT55_PIN
-	static void isr55(void) { update(interruptArgs[55]); }
-	#endif
-	#ifdef CORE_INT56_PIN
-	static void isr56(void) { update(interruptArgs[56]); }
-	#endif
-	#ifdef CORE_INT57_PIN
-	static void isr57(void) { update(interruptArgs[57]); }
-	#endif
-	#ifdef CORE_INT58_PIN
-	static void isr58(void) { update(interruptArgs[58]); }
-	#endif
-	#ifdef CORE_INT59_PIN
-	static void isr59(void) { update(interruptArgs[59]); }
-	#endif
-#endif
 };
 
 #if defined(ENCODER_USE_INTERRUPTS) && defined(ENCODER_OPTIMIZE_INTERRUPTS)