1 files changed, 131 insertions, 0 deletions
diff --git a/tests/qtest/cmsdk-apb-watchdog-test.c b/tests/qtest/cmsdk-apb-watchdog-test.c
new file mode 100644
index 0000000..2710cb1
--- /dev/null
+++ b/tests/qtest/cmsdk-apb-watchdog-test.c
@@ -0,0 +1,131 @@
+/*
+ * QTest testcase for the CMSDK APB watchdog device
+ *
+ * Copyright (c) 2021 Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/bitops.h"
+#include "libqtest-single.h"
+
+/*
+ * lm3s811evb watchdog; at board startup this runs at 200MHz / 16 == 12.5MHz,
+ * which is 80ns per tick.
+ */
+#define WDOG_BASE 0x40000000
+
+#define WDOGLOAD 0
+#define WDOGVALUE 4
+#define WDOGCONTROL 8
+#define WDOGINTCLR 0xc
+#define WDOGRIS 0x10
+#define WDOGMIS 0x14
+#define WDOGLOCK 0xc00
+
+#define SSYS_BASE 0x400fe000
+#define RCC 0x60
+#define SYSDIV_SHIFT 23
+#define SYSDIV_LENGTH 4
+
+static void test_watchdog(void)
+{
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 0);
+
+    writel(WDOG_BASE + WDOGCONTROL, 1);
+    writel(WDOG_BASE + WDOGLOAD, 1000);
+
+    /* Step to just past the 500th tick */
+    clock_step(500 * 80 + 1);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 0);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 500);
+
+    /* Just past the 1000th tick: timer should have fired */
+    clock_step(500 * 80);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 1);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 0);
+
+    /* VALUE reloads at following tick */
+    clock_step(80);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 1000);
+
+    /* Writing any value to WDOGINTCLR clears the interrupt and reloads */
+    clock_step(500 * 80);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 500);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 1);
+    writel(WDOG_BASE + WDOGINTCLR, 0);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 1000);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 0);
+}
+
+static void test_clock_change(void)
+{
+    uint32_t rcc;
+
+    /*
+     * Test that writing to the stellaris board's RCC register to
+     * change the system clock frequency causes the watchdog
+     * to change the speed it counts at.
+     */
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 0);
+
+    writel(WDOG_BASE + WDOGCONTROL, 1);
+    writel(WDOG_BASE + WDOGLOAD, 1000);
+
+    /* Step to just past the 500th tick */
+    clock_step(80 * 500 + 1);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 0);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 500);
+
+    /* Rewrite RCC.SYSDIV from 16 to 8, so the clock is now 40ns per tick */
+    rcc = readl(SSYS_BASE + RCC);
+    g_assert_cmpuint(extract32(rcc, SYSDIV_SHIFT, SYSDIV_LENGTH), ==, 0xf);
+    rcc = deposit32(rcc, SYSDIV_SHIFT, SYSDIV_LENGTH, 7);
+    writel(SSYS_BASE + RCC, rcc);
+
+    /* Just past the 1000th tick: timer should have fired */
+    clock_step(40 * 500);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 1);
+
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 0);
+
+    /* VALUE reloads at following tick */
+    clock_step(41);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 1000);
+
+    /* Writing any value to WDOGINTCLR clears the interrupt and reloads */
+    clock_step(40 * 500);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 500);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 1);
+    writel(WDOG_BASE + WDOGINTCLR, 0);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGVALUE), ==, 1000);
+    g_assert_cmpuint(readl(WDOG_BASE + WDOGRIS), ==, 0);
+}
+
+int main(int argc, char **argv)
+{
+    int r;
+
+    g_test_init(&argc, &argv, NULL);
+
+    qtest_start("-machine lm3s811evb");
+
+    qtest_add_func("/cmsdk-apb-watchdog/watchdog", test_watchdog);
+    qtest_add_func("/cmsdk-apb-watchdog/watchdog_clock_change",
+                   test_clock_change);
+
+    r = g_test_run();
+
+    qtest_end();
+
+    return r;
+}