[Qemu-devel] [kvm-unit-tests PATCH 1/4] arm/arm64: GIC: basic GICv2 MMIO tests

[Andre Przywara]

This adds an MMIO subtest to the GIC test.
It accesses some generic GICv2 registers and does some sanity tests,
like checking for some of them being read-only.

Signed-off-by: Andre Przywara <address@hidden>
---
 arm/gic.c         | 99 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 arm/unittests.cfg |  6 ++++
 lib/arm/asm/gic.h |  2 ++
 3 files changed, 107 insertions(+)

diff --git a/arm/gic.c b/arm/gic.c
index 638b8b1..ba2585b 100644
--- a/arm/gic.c
+++ b/arm/gic.c
@@ -3,6 +3,7 @@
  *
  * GICv2
  *   + test sending/receiving IPIs
+ *   + MMIO access tests
  * GICv3
  *   + test sending/receiving IPIs
  *
@@ -274,6 +275,98 @@ static struct gic gicv3 = {
        },
 };
 
+static bool test_ro_pattern_32(void *address, u32 pattern, u32 orig)
+{
+       u32 reg;
+
+       writel(pattern, address);
+       reg = readl(address);
+
+       if (reg != orig)
+               writel(orig, address);
+
+       return reg == orig;
+}
+
+static bool test_readonly_32(void *address, bool razwi)
+{
+       u32 orig, pattern;
+
+       orig = readl(address);
+       if (razwi && orig)
+               return false;
+
+       pattern = 0xffffffff;
+       if (orig != pattern) {
+               if (!test_ro_pattern_32(address, pattern, orig))
+                       return false;
+       }
+
+       pattern = 0xa5a55a5a;
+       if (orig != pattern) {
+               if (!test_ro_pattern_32(address, pattern, orig))
+                       return false;
+       }
+
+       pattern = 0;
+       if (orig != pattern) {
+               if (!test_ro_pattern_32(address, pattern, orig))
+                       return false;
+       }
+
+       return true;
+}
+
+static bool test_typer_v2(uint32_t reg)
+{
+       int nr_gic_cpus = ((reg >> 5) & 0x7) + 1;
+
+       report("all %d CPUs have interrupts", nr_cpus == nr_gic_cpus,
+              nr_gic_cpus);
+
+       return true;
+}
+
+static int gic_test_mmio(int gic_version)
+{
+       u32 reg;
+       int nr_irqs;
+       void *gic_dist_base, *idreg;
+
+       switch(gic_version) {
+       case 0x2:
+               gic_dist_base = gicv2_dist_base();
+               idreg = gic_dist_base + 0xfe8;
+               break;
+       case 0x3:
+               report_abort("GICv3 MMIO tests NYI");
+               return -1;
+       default:
+               report_abort("GIC version %d not supported", gic_version);
+               return 0;
+       }
+
+       reg = readl(gic_dist_base + GICD_TYPER);
+       nr_irqs = 32 * ((reg & 0x1f) + 1);
+       report("number of implemented SPIs: %d", 1, nr_irqs - 32);
+
+       test_typer_v2(reg);
+
+       report("IIDR: 0x%x", 1, readl(gic_dist_base + GICD_IIDR));
+
+       report("GICD_TYPER is read-only",
+              test_readonly_32(gic_dist_base + GICD_TYPER, false));
+       report("GICD_IIDR is read-only",
+              test_readonly_32(gic_dist_base + GICD_IIDR, false));
+
+       reg = readl(idreg);
+       report("ICPIDR2 is read-only (0x%x)",
+              test_readonly_32(idreg, false),
+              reg);
+
+       return 0;
+}
+
 int main(int argc, char **argv)
 {
        char pfx[8];
@@ -332,6 +425,12 @@ int main(int argc, char **argv)
                }
                ipi_test();
 
+       } else if (!strcmp(argv[1], "mmio")) {
+               report_prefix_push(argv[1]);
+
+               gic_test_mmio(gic_version());
+
+               report_prefix_pop();
        } else {
                report_abort("Unknown subtest '%s'", argv[1]);
        }
diff --git a/arm/unittests.cfg b/arm/unittests.cfg
index c7392c7..0162e5a 100644
--- a/arm/unittests.cfg
+++ b/arm/unittests.cfg
@@ -67,6 +67,12 @@ smp = $((($MAX_SMP < 8)?$MAX_SMP:8))
 extra_params = -machine gic-version=2 -append 'ipi'
 groups = gic
 
+[gicv2-mmio]
+file = gic.flat
+smp = $((($MAX_SMP < 8)?$MAX_SMP:8))
+extra_params = -machine gic-version=2 -append 'mmio'
+groups = gic
+
 [gicv3-ipi]
 file = gic.flat
 smp = $MAX_SMP
diff --git a/lib/arm/asm/gic.h b/lib/arm/asm/gic.h
index c2267b6..cef748d 100644
--- a/lib/arm/asm/gic.h
+++ b/lib/arm/asm/gic.h
@@ -10,10 +10,12 @@
 /* Distributor registers */
 #define GICD_CTLR                      0x0000
 #define GICD_TYPER                     0x0004
+#define GICD_IIDR                      0x0008
 #define GICD_IGROUPR                   0x0080
 #define GICD_ISENABLER                 0x0100
 #define GICD_IPRIORITYR                        0x0400
 #define GICD_SGIR                      0x0f00
+#define GICD_ICPIDR2                   0x0fe8
 
 #define GICD_TYPER_IRQS(typer)         ((((typer) & 0x1f) + 1) * 32)
 #define GICD_INT_EN_SET_SGI            0x0000ffff
-- 
2.9.0