[Qemu-devel] [PATCH 9/9] arm: Set frequencies for arm_timer

[Qemu-devel] [PATCH 9/9] arm: Set frequencies for arm_timer

[Mark Langsdorf]

Use qdev properties to allow board modelers to set the frequencies
for the sp804 timer. Each of the sp804's timers can have an
individual frequency or they share the frequency by default.
The timers default to 1MHz.

Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com>
---
  hw/arm_timer.c |   36 +++++++++++++++++++++++++++++++-----
  1 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/hw/arm_timer.c b/hw/arm_timer.c
index 0a5b9d2..4cafa1f 100644
--- a/hw/arm_timer.c
+++ b/hw/arm_timer.c
@@ -9,6 +9,8 @@

  #include "sysbus.h"
  #include "qemu-timer.h"
+#include "qemu-common.h"
+#include "qdev.h"

  /* Common timer implementation.  */

@@ -178,6 +180,8 @@ typedef struct {
      SysBusDevice busdev;
      MemoryRegion iomem;
      arm_timer_state *timer[2];
+    int freq0, freq1;
+    int freq;
      int level[2];
      qemu_irq irq;
  } sp804_state;
@@ -269,10 +273,21 @@ static int sp804_init(SysBusDevice *dev)

      qi = qemu_allocate_irqs(sp804_set_irq, s, 2);
      sysbus_init_irq(dev, &s->irq);
-    /* ??? The timers are actually configurable between 32kHz and 1MHz, but
-       we don't implement that.  */
-    s->timer[0] = arm_timer_init(1000000);
-    s->timer[1] = arm_timer_init(1000000);
+    /* The timers are configurable between 32kHz and 1MHz
+     * defaulting to 1MHz but overrideable as a property
+     * They can be configured individually as a property
+     * but default is shared frequency */
+    if (s->freq0) {
+        s->timer[0] = arm_timer_init(s->freq0);
+    } else {
+        s->timer[0] = arm_timer_init(s->freq);
+    }
+    if (s->freq1) {
+        s->timer[1] = arm_timer_init(s->freq1);
+    } else {
+        s->timer[1] = arm_timer_init(s->freq);
+    }
+
      s->timer[0]->irq = qi[0];
      s->timer[1]->irq = qi[1];
      memory_region_init_io(&s->iomem, &sp804_ops, s, "sp804", 0x1000);
@@ -281,6 +296,17 @@ static int sp804_init(SysBusDevice *dev)
      return 0;
  }

+static SysBusDeviceInfo sp804_info = {
+    .init = sp804_init,
+    .qdev.name = "sp804",
+    .qdev.size = sizeof(sp804_state),
+    .qdev.props = (Property[]) {
+        DEFINE_PROP_INT32("freq", sp804_state, freq, 1000000),
+        DEFINE_PROP_INT32("freq0", sp804_state, freq0, 0),
+        DEFINE_PROP_INT32("freq1", sp804_state, freq1, 0),
+        DEFINE_PROP_END_OF_LIST(),
+    }
+};

  /* Integrator/CP timer module.  */

@@ -349,7 +375,7 @@ static int icp_pit_init(SysBusDevice *dev)
  static void arm_timer_register_devices(void)
  {
      sysbus_register_dev("integrator_pit", sizeof(icp_pit_state), 
icp_pit_init);
-    sysbus_register_dev("sp804", sizeof(sp804_state), sp804_init);
+    sysbus_register_withprop(&sp804_info);
  }

  device_init(arm_timer_register_devices)
-- 
1.7.5.4

Re: [Qemu-devel] [PATCH 9/9] arm: Set frequencies for arm_timer

[Peter Maydell]

On 20 December 2011 19:15, Mark Langsdorf <mark.langsdorf@calxeda.com> wrote:
> Use qdev properties to allow board modelers to set the frequencies
> for the sp804 timer. Each of the sp804's timers can have an
> individual frequency or they share the frequency by default.
> The timers default to 1MHz.

Is it really worth having separate properties for "timer 1 freq",
"timer 2 freq", and "shared default freq" ? It doesn't seem like
a big deal to me to have the board modeller set both the freq0
and freq1 properties even if they're both the same thing.
That would simplify the code here rather.

-- PMM