Support neopixel primitives on Zephyr (rpi_pico)

platforms/Zephyr/boards/rpi_pico.overlay

@@ -1,6 +1,11 @@
 #include "../app.overlay"
+#include <zephyr/dt-bindings/led/led.h>
 
 / {
+    aliases {
+        led-strip = &ws2812;
+    };
+
     zephyr,user {
         warduino-gpios =
             <&gpio0 0 0>,
@@ -34,4 +39,39 @@
             <&gpio0 28 0>,
             <&gpio0 29 0>;
      };
-}; 
+};
+
+&pio1 {
+    status = "okay";
+
+    /*
+	 * Need to put this on PIO1 as having this on PIO0 causes the GPIO hog to
+	 * not work.
+	 */
+    pio-ws2812 {
+        compatible = "worldsemi,ws2812-rpi_pico-pio";
+        status = "okay";
+        pinctrl-0 = <&ws2812_pio1_default>;
+        pinctrl-names = "default";
+        bit-waveform = <3>, <3>, <4>;
+
+        ws2812: ws2812 {
+            status = "okay";
+            gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
+            chain-length = <64>;
+            color-mapping = <LED_COLOR_ID_GREEN
+                             LED_COLOR_ID_RED
+                             LED_COLOR_ID_BLUE>;
+            reset-delay = <280>;
+            frequency = <800000>;
+        };
+    };
+};
+
+&pinctrl {
+    ws2812_pio1_default: ws2812_pio1_default {
+        ws2812 {
+            pinmux = <PIO1_P12>;
+        };
+    };
+};

platforms/Zephyr/prj.conf

@@ -30,3 +30,7 @@ CONFIG_CONSOLE_PUTCHAR_BUFSIZE=4096
 
 CONFIG_POSIX_API=y
 CONFIG_MAIN_STACK_SIZE=8192
+
+CONFIG_LOG=y
+CONFIG_LED_STRIP=y
+CONFIG_LED_STRIP_LOG_LEVEL_DBG=n

src/Primitives/zephyr.cpp

@@ -20,6 +20,7 @@
 #include <zephyr/drivers/uart.h>
 #include <zephyr/dt-bindings/gpio/gpio.h>
 #include <zephyr/kernel.h>
+#include <zephyr/drivers/led_strip.h>
 
 #include <chrono>
 #include <cmath>
@@ -32,7 +33,7 @@
 #include "../Utils/util.h"
 #include "primitives.h"
 
-#define ALL_PRIMITIVES 5
+#define ALL_PRIMITIVES 7
 
 // Global index for installing primitives
 int prim_index = 0;
@@ -262,6 +263,86 @@ def_prim(print_int, oneToNoneU32) {
     return true;
 }
 
+static const device *const strip = DEVICE_DT_GET(DT_ALIAS(led_strip));
+const size_t strip_length = 64;//led_strip_length(device);
+led_rgb pixels[strip_length] = {0};
+led_rgb pixels_shown[strip_length] = {0};
+
+def_prim(show_pixels, NoneToNoneU32) {
+    memcpy(pixels_shown, pixels, strip_length * sizeof(led_rgb));
+    int rc = led_strip_update_rgb(strip, pixels_shown, strip_length);
+    if (rc) {
+        printf("couldn't update strip: %d", rc);
+    }
+    return true;
+}
+
+def_prim_serialize(show_pixels) {
+    for (int i = 0; i < strip_length; i++) {
+        auto *state = new IOStateElement();
+        state->key = "n" + std::to_string(i);
+        state->output = true;
+        state->value = pixels_shown[i].r << 16 | pixels_shown[i].g << 8 | pixels_shown[i].b;
+        external_state.push_back(state);
+    }
+}
+
+def_prim_reverse(show_pixels) {
+    for (IOStateElement state : external_state) {
+        if (!state.output) {
+            continue;
+        }
+
+        if (state.key[0] == 'n') {
+            int index = stoi(state.key.substr(1));
+            pixels_shown[index].r = ((uint32_t) state.value >> 16) & 0xff;
+            pixels_shown[index].g = ((uint32_t) state.value >> 8) & 0xff;
+            pixels_shown[index].b = state.value & 0xff;
+            int rc = led_strip_update_rgb(strip, pixels_shown, strip_length);
+    		if (rc) {
+        		printf("couldn't update strip: %d", rc);
+    		}
+        }
+    }
+}
+
+def_prim(set_pixel_color, fourToOneU32) {
+    uint8_t blue = arg0.uint32;
+    uint8_t green = arg1.uint32;
+    uint8_t red = arg2.uint32;
+    uint8_t index = arg3.uint32;
+
+    led_rgb color = {.r = red, .g = green, .b= blue};
+    memcpy(&pixels[index], &color, sizeof(struct led_rgb));
+    pop_args(4);
+    return true;
+}
+
+def_prim_serialize(set_pixel_color) {
+    for (int i = 0; i < strip_length; i++) {
+        auto *state = new IOStateElement();
+        state->key = "b" + std::to_string(i);
+        state->output = true;
+        state->value = pixels[i].r << 16 | pixels[i].g << 8 | pixels[i].b;
+        external_state.push_back(state);
+    }
+}
+
+def_prim_reverse(set_pixel_color) {
+    for (IOStateElement state : external_state) {
+        if (!state.output) {
+            continue;
+        }
+
+        if (state.key[0] == 'b') {
+            int index = stoi(state.key.substr(1));
+            pixels[index].r = ((uint32_t) state.value >> 16) & 0xff;
+            pixels[index].g = ((uint32_t) state.value >> 8) & 0xff;
+            pixels[index].b = state.value & 0xff;
+        }
+    }
+}
+
 //------------------------------------------------------
 // Installing all the primitives
 //------------------------------------------------------
@@ -272,6 +353,10 @@ void install_primitives() {
     install_primitive(chip_digital_write);
     install_primitive(chip_digital_read);
     install_primitive(print_int);
+    install_primitive(set_pixel_color);
+    install_primitive_reverse(set_pixel_color);
+    install_primitive(show_pixels);
+    install_primitive_reverse(show_pixels);
 }
 
 //------------------------------------------------------
@@ -317,25 +402,12 @@ bool resolve_external_memory(char *symbol, Memory **val) {
 //------------------------------------------------------
 void restore_external_state(Module *m,
                             const std::vector<IOStateElement> &external_state) {
-    uint8_t opcode = *m->pc_ptr;
-    // TODO: Maybe primitives can also be called using the other call
-    // instructions such as call_indirect
-    //  maybe there should just be a function that checks if a certain function
-    //  is being called that handles all these cases?
-    if (opcode == 0x10) {  // call opcode
-        uint8_t *pc_copy = m->pc_ptr + 1;
-        uint32_t fidx = read_LEB_32(&pc_copy);
-        if (fidx < m->import_count) {
-            for (auto &primitive : primitives) {
-                if (!strcmp(primitive.name, m->functions[fidx].import_field)) {
-                    if (primitive.f_reverse) {
-                        debug("Reversing action for primitive %s\n",
-                              primitive.name);
-                        primitive.f_reverse(m, external_state);
-                    }
-                    return;
-                }
-            }
+    for (int i = 0; i < ALL_PRIMITIVES; i++) {
+        auto primitive = primitives[i];
+        if (primitive.f_reverse) {
+            debug("Reversing action for primitive %s\n",
+                  primitive.name);
+            primitive.f_reverse(m, external_state);
         }
     }
 }