tests/qtest/sse-timer-test: Add simple test of the SSE counter

Add a simple qtest to exercise the new system counter device in the
SSE-300.

We'll add tests of the system timer device here too, so this includes
scaffolding (register definitions, etc) for those.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210219144617.4782-45-peter.maydell@linaro.org

1 files changed, 117 insertions, 0 deletions

diff --git a/tests/qtest/sse-timer-test.c b/tests/qtest/sse-timer-test.c
new file mode 100644
index 0000000..5b86ef6
--- /dev/null
+++ b/tests/qtest/sse-timer-test.c
@@ -0,0 +1,117 @@
+/*
+ * QTest testcase for the SSE timer 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 "libqtest-single.h"
+
+/*
+ * SSE-123/SSE-300 timer in the mps3-an547 board, where it is driven
+ * at 32MHz, so 31.25ns per tick.
+ */
+#define TIMER_BASE 0x48000000
+
+/* PERIPHNSPPC0 register in the SSE-300 Secure Access Configuration block */
+#define PERIPHNSPPC0 (0x50080000 + 0x70)
+
+/* Base of the System Counter control frame */
+#define COUNTER_BASE 0x58100000
+
+/* SSE counter register offsets in the control frame */
+#define CNTCR 0
+#define CNTSR 0x4
+#define CNTCV_LO 0x8
+#define CNTCV_HI 0xc
+#define CNTSCR 0x10
+
+/* SSE timer register offsets */
+#define CNTPCT_LO 0
+#define CNTPCT_HI 4
+#define CNTFRQ 0x10
+#define CNTP_CVAL_LO 0x20
+#define CNTP_CVAL_HI 0x24
+#define CNTP_TVAL 0x28
+#define CNTP_CTL 0x2c
+#define CNTP_AIVAL_LO 0x40
+#define CNTP_AIVAL_HI 0x44
+#define CNTP_AIVAL_RELOAD 0x48
+#define CNTP_AIVAL_CTL 0x4c
+
+/* 4 ticks in nanoseconds (so we can work in integers) */
+#define FOUR_TICKS 125
+
+static void clock_step_ticks(uint64_t ticks)
+{
+    /*
+     * Advance the qtest clock by however many nanoseconds we
+     * need to move the timer forward the specified number of ticks.
+     * ticks must be a multiple of 4, so we get a whole number of ns.
+     */
+    assert(!(ticks & 3));
+    clock_step(FOUR_TICKS * (ticks >> 2));
+}
+
+static void reset_counter_and_timer(void)
+{
+    /*
+     * Reset the system counter and the timer between tests. This
+     * isn't a full reset, but it's sufficient for what the tests check.
+     */
+    writel(COUNTER_BASE + CNTCR, 0);
+    writel(TIMER_BASE + CNTP_CTL, 0);
+    writel(TIMER_BASE + CNTP_AIVAL_CTL, 0);
+    writel(COUNTER_BASE + CNTCV_LO, 0);
+    writel(COUNTER_BASE + CNTCV_HI, 0);
+}
+
+static void test_counter(void)
+{
+    /* Basic counter functionality test */
+
+    reset_counter_and_timer();
+    /* The counter should start disabled: check that it doesn't move */
+    clock_step_ticks(100);
+    g_assert_cmpuint(readl(COUNTER_BASE + CNTCV_LO), ==, 0);
+    g_assert_cmpuint(readl(COUNTER_BASE + CNTCV_HI), ==, 0);
+    /* Now enable it and check that it does count */
+    writel(COUNTER_BASE + CNTCR, 1);
+    clock_step_ticks(100);
+    g_assert_cmpuint(readl(COUNTER_BASE + CNTCV_LO), ==, 100);
+    g_assert_cmpuint(readl(COUNTER_BASE + CNTCV_HI), ==, 0);
+    /* Check the counter scaling functionality */
+    writel(COUNTER_BASE + CNTCR, 0);
+    writel(COUNTER_BASE + CNTSCR, 0x00100000); /* 1/16th normal speed */
+    writel(COUNTER_BASE + CNTCR, 5); /* EN, SCEN */
+    clock_step_ticks(160);
+    g_assert_cmpuint(readl(COUNTER_BASE + CNTCV_LO), ==, 110);
+    g_assert_cmpuint(readl(COUNTER_BASE + CNTCV_HI), ==, 0);
+}
+
+int main(int argc, char **argv)
+{
+    int r;
+
+    g_test_init(&argc, &argv, NULL);
+
+    qtest_start("-machine mps3-an547");
+
+    qtest_add_func("/sse-timer/counter", test_counter);
+
+    r = g_test_run();
+
+    qtest_end();
+
+    return r;
+}