Try adding w5500-test, though it doesn't fit

flake.lock

@@ -10,11 +10,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1699827895,
-        "narHash": "sha256-Fzjd9h3TDPXORNl6pek+e79eFjbmSaU4Hi/MUpjSRz4=",
+        "lastModified": 1699858083,
+        "narHash": "sha256-EXmVoYDYszdWlaxRzedQ3Q7ehbqIGfbe9EaHSBD4cgQ=",
         "ref": "refs/heads/canon",
-        "rev": "763d83f15705ab6c6b033e445f96d40bc4f10eb4",
-        "revCount": 9,
+        "rev": "453af715eebd7102131d2cc6846dd23d49f853ac",
+        "revCount": 12,
         "type": "git",
         "url": "https://git.mildlyfunctional.gay/artemist/packages.git"
       },

flake.nix

@@ -19,12 +19,8 @@
                 arm-zephyr-eabi
                 riscv64-zephyr-elf
               ];
-            zephyrSrc = pkgs.fetchFromGitHub {
-              owner = "zephyrproject-rtos";
-              repo = "zephyr";
-              rev = "v3.5.0";
-              hash = "sha256-72QFsKOWkF6BiP4XgZAXXSBcN4t6yvhAeXCpgCYrhe8=";
-            };
+            modules = with artemist-packages.packages.${system}.zephyr.modules;
+              [ mbedtls ];
           };
         formatter = pkgs.nixfmt;
       });

zephyr/.gitignore

@@ -1 +1,2 @@
 build/
+.cache/

zephyr/w5500-test/CMakeLists.txt

@@ -0,0 +1,5 @@
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+
+project(w5500-test)
+target_sources(app PRIVATE src/main.c)

zephyr/w5500-test/boards/sparkfun_red_v_things_plus.overlay

@@ -0,0 +1,10 @@
+&spi1 {
+	cs-gpios = <&gpio0 9 GPIO_ACTIVE_LOW>;
+	
+	w5500@0 {
+		compatible = "wiznet,w5500";
+		reg = <0>;
+		int-gpios = <&gpio0 10 GPIO_ACTIVE_LOW>;
+		spi-max-frequency = <10000000>;
+	};
+};

zephyr/w5500-test/prj.conf

@@ -0,0 +1,11 @@
+CONFIG_NET_L2_ETHERNET=y
+CONFIG_ETH_DRIVER=y
+CONFIG_ETH_W5500=y
+
+CONFIG_NETWORKING=y
+CONFIG_NET_IPV6=y
+CONFIG_NET_TCP=y
+
+CONFIG_NET_SOCKETS=y
+CONFIG_NET_SOCKETS_POSIX_NAMES=y
+CONFIG_NET_SOCKETS_POLL_MAX=4

zephyr/w5500-test/src/main.c

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2016 Intel Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/kernel.h>
+#include <zephyr/drivers/gpio.h>
+
+/* 1000 msec = 1 sec */
+#define SLEEP_TIME_MS   1000
+
+/* The devicetree node identifier for the "led0" alias. */
+#define LED0_NODE DT_ALIAS(led0)
+
+/*
+ * A build error on this line means your board is unsupported.
+ * See the sample documentation for information on how to fix this.
+ */
+static const struct gpio_dt_spec led = GPIO_DT_SPEC_GET(LED0_NODE, gpios);
+
+int main(void)
+{
+	int ret;
+
+	if (!gpio_is_ready_dt(&led)) {
+		return 0;
+	}
+
+	ret = gpio_pin_configure_dt(&led, GPIO_OUTPUT_ACTIVE);
+	if (ret < 0) {
+		return 0;
+	}
+
+	while (1) {
+		ret = gpio_pin_toggle_dt(&led);
+		if (ret < 0) {
+			return 0;
+		}
+		k_msleep(SLEEP_TIME_MS);
+	}
+	return 0;
+}
+