tests: interrupt: Add tests for shared irqs

Add test case of shared interrupts. This tests
that IRQs are shared when IRQ_CONNECT is called
multiple times on the same IRQ with different
ISR handlers.

Signed-off-by: Sam Hurst <sbh1187@gmail.com>

tests/kernel/interrupt/CMakeLists.txt

@@ -15,5 +15,6 @@ target_sources(app PRIVATE
     src/nested_irq.c
     )
 
+target_sources_ifdef(CONFIG_ISR_SHARE_IRQ app PRIVATE src/shared_irq.c)
 target_sources_ifdef(CONFIG_DYNAMIC_INTERRUPTS app PRIVATE src/dynamic_isr.c)
 target_sources_ifdef(CONFIG_X86 app PRIVATE src/regular_isr.c)

tests/kernel/interrupt/src/shared_irq.c

@@ -0,0 +1,122 @@
+/*
+ * Copyright 2022 The Chromium OS Authors
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/ztest.h>
+#include <zephyr/interrupt_util.h>
+
+#define DURATION        5
+
+#if defined(CONFIG_GIC)
+#define ISR0_OFFSET	10
+#define ISR1_2_OFFSET	11
+#define ISR3_4_5_OFFSET	12
+#define ISR6_OFFSET	13
+#else
+/* Offset for the interrupt used in this test. */
+#define ISR0_OFFSET     (CONFIG_NUM_IRQS - 7)
+#define ISR1_2_OFFSET   (CONFIG_NUM_IRQS - 6)
+#define ISR3_4_5_OFFSET (CONFIG_NUM_IRQS - 5)
+#define ISR6_OFFSET     (CONFIG_NUM_IRQS - 4)
+#endif
+
+#define MAX_ISR_TESTS 7
+
+static volatile int test_flag[MAX_ISR_TESTS] = {0};
+
+static void isr0(void *arg)
+{
+	int value = POINTER_TO_INT(arg);
+
+	test_flag[0] = value;
+}
+
+static void share_isr1(void *arg)
+{
+	int value = POINTER_TO_INT(arg);
+
+	test_flag[1] = value;
+}
+
+static void share_isr2(void *arg)
+{
+	int value = POINTER_TO_INT(arg);
+
+	test_flag[2] = value;
+}
+
+static void share_isr3(void *arg)
+{
+	int value = POINTER_TO_INT(arg);
+
+	test_flag[3] = value;
+}
+
+static void share_isr4(void *arg)
+{
+	int value = POINTER_TO_INT(arg);
+
+	test_flag[4] = value;
+}
+
+static void share_isr5(void *arg)
+{
+	int value = POINTER_TO_INT(arg);
+
+	test_flag[5] = value;
+}
+
+static void isr6(void *arg)
+{
+	int value = POINTER_TO_INT(arg);
+
+	test_flag[6] = value;
+}
+
+/**
+ * @brief Test shared interrupt
+ *
+ * @details Validate that shared interrupts work as expected.
+ * - Register two regular interrupt at build time.
+ * - Two shared interrupts at build time.
+ * - Three shared interrupts at build time.
+ * - Trigger interrupts and check if isrs handler are executed or not.
+ *
+ * @ingroup kernel_interrupt_tests
+ */
+ZTEST(interrupt_feature, test_shared_irq)
+{
+	/* Ensure the IRQ is disabled before enabling it at run time */
+	irq_disable(ISR0_OFFSET);
+	irq_disable(ISR1_2_OFFSET);
+	irq_disable(ISR3_4_5_OFFSET);
+	irq_disable(ISR6_OFFSET);
+
+	/* Place the non-direct shared interrupts */
+	IRQ_CONNECT(ISR0_OFFSET,     0, isr0,       (void *)1, 0);
+	IRQ_CONNECT(ISR1_2_OFFSET,   0, share_isr1, (void *)2, 0);
+	IRQ_CONNECT(ISR1_2_OFFSET,   0, share_isr2, (void *)3, 0);
+	IRQ_CONNECT(ISR3_4_5_OFFSET, 0, share_isr3, (void *)4, 0);
+	IRQ_CONNECT(ISR3_4_5_OFFSET, 0, share_isr4, (void *)5, 0);
+	IRQ_CONNECT(ISR3_4_5_OFFSET, 0, share_isr5, (void *)6, 0);
+	IRQ_CONNECT(ISR6_OFFSET,     0, isr6,       (void *)7, 0);
+
+	/* Enable and pend the interrupts */
+	irq_enable(ISR0_OFFSET);
+	irq_enable(ISR1_2_OFFSET);
+	irq_enable(ISR3_4_5_OFFSET);
+	irq_enable(ISR6_OFFSET);
+
+	/* Trigger the interrupts */
+	trigger_irq(ISR0_OFFSET);
+	trigger_irq(ISR1_2_OFFSET);
+	trigger_irq(ISR3_4_5_OFFSET);
+	trigger_irq(ISR6_OFFSET);
+	k_busy_wait(MS_TO_US(DURATION));
+
+	for (int i = 0; i < MAX_ISR_TESTS; i++) {
+		zassert_true(test_flag[i] == i + 1, "Test flag not set by ISR%d\n", i);
+	}
+}

tests/kernel/interrupt/testcase.yaml

@@ -11,3 +11,10 @@ tests:
     filter: not CONFIG_TRUSTED_EXECUTION_NONSECURE
     extra_configs:
       - CONFIG_CMAKE_LINKER_GENERATOR=y
+
+  arch.interrupt.isr_share_irq:
+    platform_allow: qemu_cortex_m0 qemu_cortex_m3 qemu_cortex_a9 qemu_cortex_a53 qemu_cortex_a53_smp
+    tags: kernel interrupt isr_share_irq
+    filter: not CONFIG_TRUSTED_EXECUTION_NONSECURE
+    extra_configs:
+      - CONFIG_ISR_SHARE_IRQ=y