[kvm-unit-tests PATCH v2 08/10] arm/arm64: gicv2: add an IPI test

Andrew Jones
2016-06-04T18:16:03Z

Signed-off-by: Andrew Jones <drjones@redhat.com>
---
v2: add more details in the output if a test fails,
report spurious interrupts if we get them
---
arm/Makefile.common | 6 +-
arm/gic.c | 194 ++++++++++++++++++++++++++++++++++++++++++++++++++++
arm/unittests.cfg | 7 ++
3 files changed, 204 insertions(+), 3 deletions(-)
create mode 100644 arm/gic.c

diff --git a/arm/Makefile.common b/arm/Makefile.common
index 0dc9cac241007..c641f6e4f15d3 100644
--- a/arm/Makefile.common
+++ b/arm/Makefile.common
@@ -9,9 +9,9 @@ ifeq ($(LOADADDR),)
LOADADDR = 0x40000000
endif

-tests-common = \
- $(TEST_DIR)/selftest.flat \
- $(TEST_DIR)/spinlock-test.flat
+tests-common = $(TEST_DIR)/selftest.flat
+tests-common += $(TEST_DIR)/spinlock-test.flat
+tests-common += $(TEST_DIR)/gic.flat

all: test_cases

diff --git a/arm/gic.c b/arm/gic.c
new file mode 100644
index 0000000000000..cf7ec1c90413c
--- /dev/null
+++ b/arm/gic.c
@@ -0,0 +1,194 @@
+/*
+ * GIC tests
+ *
+ * GICv2
+ * . test sending/receiving IPIs
+ *
+ * Copyright (C) 2016, Red Hat Inc, Andrew Jones <drjones@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.
+ */
+#include <libcflat.h>
+#include <asm/setup.h>
+#include <asm/processor.h>
+#include <asm/gic.h>
+#include <asm/smp.h>
+#include <asm/barrier.h>
+#include <asm/io.h>
+
+static int gic_version;
+static int acked[NR_CPUS], spurious[NR_CPUS];
+static cpumask_t ready;
+
+static void nr_cpu_check(int nr)
+{
+ if (nr_cpus < nr)
+ report_abort("At least %d cpus required", nr);
+}
+
+static void wait_on_ready(void)
+{
+ cpumask_set_cpu(smp_processor_id(), &ready);
+ while (!cpumask_full(&ready))
+ cpu_relax();
+}
+
+static void check_acked(cpumask_t *mask)
+{
+ int missing = 0, extra = 0, unexpected = 0;
+ int nr_pass, cpu, i;
+
+ /* Wait up to 5s for all interrupts to be delivered */
+ for (i = 0; i < 50; ++i) {
+ mdelay(100);
+ nr_pass = 0;
+ for_each_present_cpu(cpu) {
+ smp_rmb();
+ nr_pass += cpumask_test_cpu(cpu, mask) ?
+ acked[cpu] == 1 : acked[cpu] == 0;
+ }
+ if (nr_pass == nr_cpus) {
+ report("Completed in %d ms", true, ++i * 100);
+ return;
+ }
+ }
+
+ for_each_present_cpu(cpu) {
+ if (cpumask_test_cpu(cpu, mask)) {
+ if (!acked[cpu])
+ ++missing;
+ else if (acked[cpu] > 1)
+ ++extra;
+ } else {
+ if (acked[cpu])
+ ++unexpected;
+ }
+ }
+
+ report("Timed-out (5s). ACKS: missing=%d extra=%d unexpected=%d",
+ false, missing, extra, unexpected);
+}
+
+static void ipi_handler(struct pt_regs *regs __unused)
+{
+ u32 iar = readl(gicv2_cpu_base() + GIC_CPU_INTACK);
+
+ if (iar != GICC_INT_SPURIOUS) {
+ writel(iar, gicv2_cpu_base() + GIC_CPU_EOI);
+ smp_rmb(); /* pairs with wmb in ipi_test functions */
+ ++acked[smp_processor_id()];
+ smp_wmb(); /* pairs with rmb in check_acked */
+ } else {
+ ++spurious[smp_processor_id()];
+ smp_wmb();
+ }
+}
+
+static void ipi_test_self(void)
+{
+ cpumask_t mask;
+
+ report_prefix_push("self");
+ memset(acked, 0, sizeof(acked));
+ smp_wmb();
+ cpumask_clear(&mask);
+ cpumask_set_cpu(0, &mask);
+ writel(2 << 24, gicv2_dist_base() + GIC_DIST_SOFTINT);
+ check_acked(&mask);
+ report_prefix_pop();
+}
+
+static void ipi_test_smp(void)
+{
+ cpumask_t mask;
+ unsigned long tlist;
+
+ report_prefix_push("target-list");
+ memset(acked, 0, sizeof(acked));
+ smp_wmb();
+ tlist = cpumask_bits(&cpu_present_mask)[0] & 0xaa;
+ cpumask_bits(&mask)[0] = tlist;
+ writel((u8)tlist << 16, gicv2_dist_base() + GIC_DIST_SOFTINT);
+ check_acked(&mask);
+ report_prefix_pop();
+
+ report_prefix_push("broadcast");
+ memset(acked, 0, sizeof(acked));
+ smp_wmb();
+ cpumask_copy(&mask, &cpu_present_mask);
+ cpumask_clear_cpu(0, &mask);
+ writel(1 << 24, gicv2_dist_base() + GIC_DIST_SOFTINT);
+ check_acked(&mask);
+ report_prefix_pop();
+}
+
+static void ipi_enable(void)
+{
+ gicv2_enable_defaults();
+#ifdef __arm__
+ install_exception_handler(EXCPTN_IRQ, ipi_handler);
+#else
+ install_irq_handler(EL1H_IRQ, ipi_handler);
+#endif
+ local_irq_enable();
+}
+
+static void ipi_recv(void)
+{
+ ipi_enable();
+ cpumask_set_cpu(smp_processor_id(), &ready);
+ while (1)
+ wfi();
+}
+
+int main(int argc, char **argv)
+{
+ char pfx[8];
+ int cpu;
+
+ gic_version = gic_init();
+ if (!gic_version)
+ report_abort("No gic present!");
+
+ snprintf(pfx, 8, "gicv%d", gic_version);
+ report_prefix_push(pfx);
+
+ if (argc < 2) {
+
+ report_prefix_push("ipi");
+ ipi_enable();
+ ipi_test_self();
+ report_prefix_pop();
+
+ } else if (!strcmp(argv[1], "ipi")) {
+
+ report_prefix_push(argv[1]);
+ nr_cpu_check(2);
+ ipi_enable();
+
+ for_each_present_cpu(cpu) {
+ if (cpu == 0)
+ continue;
+ smp_boot_secondary(cpu, ipi_recv);
+ }
+ wait_on_ready();
+ ipi_test_self();
+ ipi_test_smp();
+
+ smp_rmb();
+ for_each_present_cpu(cpu) {
+ if (spurious[cpu]) {
+ printf("ipi: WARN: cpu%d got %d spurious "
+ "interrupts\n",
+ spurious[cpu], smp_processor_id());
+ }
+ }
+
+ report_prefix_pop();
+
+ } else {
+ report_abort("Unknown subtest '%s'", argv[1]);
+ }
+
+ return report_summary();
+}
diff --git a/arm/unittests.cfg b/arm/unittests.cfg
index ffd12e5794aa0..bb364675043f0 100644
--- a/arm/unittests.cfg
+++ b/arm/unittests.cfg
@@ -51,3 +51,10 @@ file = selftest.flat
smp = $MAX_SMP
extra_params = -append 'smp'
groups = selftest
+
+# Test GIC emulation
+[gicv2-ipi]
+file = gic.flat
+smp = $((($MAX_SMP < 8)?$MAX_SMP:8))
+extra_params = -machine gic-version=2 -append 'ipi'
+groups = gic
--
2.4.11