diff options
| -rw-r--r-- | hw/arm/armv7m.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/hw/arm/armv7m.c b/hw/arm/armv7m.c index ceb76df3cd..41cfca0f22 100644 --- a/hw/arm/armv7m.c +++ b/hw/arm/armv7m.c @@ -284,6 +284,12 @@ static void armv7m_realize(DeviceState *dev, Error **errp) return; } + /* cpuclk must be connected; refclk is optional */ + if (!clock_has_source(s->cpuclk)) { + error_setg(errp, "armv7m: cpuclk must be connected"); + return; + } + memory_region_add_subregion_overlap(&s->container, 0, s->board_memory, -1); s->cpu = ARM_CPU(object_new_with_props(s->cpu_type, OBJECT(s), "cpu", @@ -420,8 +426,18 @@ static void armv7m_realize(DeviceState *dev, Error **errp) &s->sysreg_ns_mem); } - /* Create and map the systick devices */ - qdev_connect_clock_in(DEVICE(&s->systick[M_REG_NS]), "refclk", s->refclk); + /* + * Create and map the systick devices. Note that we only connect + * refclk if it has been connected to us; otherwise the systick + * device gets the wrong answer for clock_has_source(refclk), because + * it has an immediate source (the ARMv7M's clock object) but not + * an ultimate source, and then it won't correctly auto-select the + * CPU clock as its only possible clock source. + */ + if (clock_has_source(s->refclk)) { + qdev_connect_clock_in(DEVICE(&s->systick[M_REG_NS]), "refclk", + s->refclk); + } qdev_connect_clock_in(DEVICE(&s->systick[M_REG_NS]), "cpuclk", s->cpuclk); if (!sysbus_realize(SYS_BUS_DEVICE(&s->systick[M_REG_NS]), errp)) { return; @@ -438,8 +454,10 @@ static void armv7m_realize(DeviceState *dev, Error **errp) */ object_initialize_child(OBJECT(dev), "systick-reg-s", &s->systick[M_REG_S], TYPE_SYSTICK); - qdev_connect_clock_in(DEVICE(&s->systick[M_REG_S]), "refclk", - s->refclk); + if (clock_has_source(s->refclk)) { + qdev_connect_clock_in(DEVICE(&s->systick[M_REG_S]), "refclk", + s->refclk); + } qdev_connect_clock_in(DEVICE(&s->systick[M_REG_S]), "cpuclk", s->cpuclk); |