[Qemu-devel] [PATCH v3 01/11] hw/intc/exynos4210_gic: Fix GIC memory mappings for secondary CPU

[Krzysztof Kozlowski <krzk@kernel.org>]

Recent Linux kernel (tested next-20170224) was complaining about missing
GIC mask and was unable to bring up secondary CPU:

    [    0.000000] NR_IRQS:16 nr_irqs:16 16
    [    0.000000] GIC CPU mask not found - kernel will fail to boot.
    ...
    [    0.400492] smp: Bringing up secondary CPUs ...
    [    1.413184] CPU1: failed to boot: -110
    [    1.423981] smp: Brought up 1 node, 1 CPU

In its instance_init() call, the Exynos GIC driver was setting GIC
memory mappings for each CPU, from 1 up to "num-cpu" property.  The
Exynos4210 machine init call on the other hand, first created Exynos GIC
device and then set the "num-cpu" property which was too late.  The init
already happened with default "num-cpu" value of 1 thus GIC mappings
were created only for the first CPU.

Split the Exynos GIC init code into realize function so the code will
see updated "num-cpu" property.  This fixes the warning and brings
second CPU:
    [    0.435780] CPU1: thread -1, cpu 1, socket 9, mpidr 80000901
    [    0.451838] smp: Brought up 1 node, 2 CPUs

Additionally this fixes missing Software Generated Interrupts (except
CPU wakeup, non of SGIs are coming) which are needed for example for IRQ
work.  Lack of IRQ work causes kernel to hang during system power off
because cpufreq_dbs_governor_stop() waits for completion with
irq_work_sync().

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
---
 hw/intc/exynos4210_gic.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/hw/intc/exynos4210_gic.c b/hw/intc/exynos4210_gic.c
index 2a55817b7660..222cfd6c6387 100644
--- a/hw/intc/exynos4210_gic.c
+++ b/hw/intc/exynos4210_gic.c
@@ -283,9 +283,20 @@ static void exynos4210_gic_set_irq(void *opaque, int irq, int level)
 
 static void exynos4210_gic_init(Object *obj)
 {
-    DeviceState *dev = DEVICE(obj);
     Exynos4210GicState *s = EXYNOS4210_GIC(obj);
-    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+
+    memory_region_init(&s->cpu_container, obj, "exynos4210-cpu-container",
+            EXYNOS4210_EXT_GIC_CPU_REGION_SIZE);
+    memory_region_init(&s->dist_container, obj, "exynos4210-dist-container",
+            EXYNOS4210_EXT_GIC_DIST_REGION_SIZE);
+
+}
+
+static void exynos4210_gic_realize(DeviceState *dev, Error **errp)
+{
+    Exynos4210GicState *s = EXYNOS4210_GIC(dev);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+    Object *obj = OBJECT(dev);
     uint32_t i;
     const char cpu_prefix[] = "exynos4210-gic-alias_cpu";
     const char dist_prefix[] = "exynos4210-gic-alias_dist";
@@ -306,11 +317,6 @@ static void exynos4210_gic_init(Object *obj)
     qdev_init_gpio_in(dev, exynos4210_gic_set_irq,
                       EXYNOS4210_GIC_NIRQ - 32);
 
-    memory_region_init(&s->cpu_container, obj, "exynos4210-cpu-container",
-            EXYNOS4210_EXT_GIC_CPU_REGION_SIZE);
-    memory_region_init(&s->dist_container, obj, "exynos4210-dist-container",
-            EXYNOS4210_EXT_GIC_DIST_REGION_SIZE);
-
     for (i = 0; i < s->num_cpu; i++) {
         /* Map CPU interface per SMP Core */
         sprintf(cpu_alias_name, "%s%x", cpu_prefix, i);
@@ -346,6 +352,7 @@ static void exynos4210_gic_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
 
+    dc->realize = exynos4210_gic_realize;
     dc->props = exynos4210_gic_properties;
 }
 
-- 
2.9.3