add circuitpython code

1 files changed, 40 insertions, 0 deletions

diff --git a/circuitpython/supervisor/shared/cpu.c b/circuitpython/supervisor/shared/cpu.c
new file mode 100644
index 0000000..d1e4114
--- /dev/null
+++ b/circuitpython/supervisor/shared/cpu.c
@@ -0,0 +1,40 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2021 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <stdint.h>
+
+#include "supervisor/shared/cpu.h"
+
+bool cpu_interrupt_active(void) {
+    #if defined(__ARM_ARCH) && (__ARM_ARCH >= 6) && defined(__ARM_ARCH_PROFILE) && (__ARM_ARCH_PROFILE == 'M')
+    // Check VECTACTIVE in ICSR. We don't need to disable interrupts because if
+    // one occurs after we read, we won't continue until it is resolved.
+    return (*((volatile uint32_t *)0xE000ED04) & 0x1ff) != 0;
+    #else
+    // We don't know.
+    return false;
+    #endif
+}