[Qemu-devel] [PATCH v3 3/3] hpet: entitle more irq pins for hpet

[Liu Ping Fan]

On q35 machine, IRQ2/8 can be reserved for hpet timer 0/1. And pin 16~23
of ioapic can be dynamically assigned to hpet as guest chooses.

Signed-off-by: Liu Ping Fan <pingf...@linux.vnet.ibm.com>
---
 hw/i386/pc.c    |  8 +++++++-
 hw/timer/hpet.c | 12 ++++++++++--
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 09c10ac..bb23d99 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1217,6 +1217,12 @@ static const MemoryRegionOps ioportF0_io_ops = {
     },
 };
 
+static void hpet_intcap_set(DeviceState *dev)
+{
+    /* For guest bug compatibility, only IRQ2 is reserved for hpet on q35 */
+    qdev_prop_set_uint32(dev, "intcap", 0x4);
+}
+
 void pc_basic_device_init(ISABus *isa_bus, qemu_irq *gsi,
                           ISADevice **rtc_state,
                           ISADevice **floppy,
@@ -1247,7 +1253,7 @@ void pc_basic_device_init(ISABus *isa_bus, qemu_irq *gsi,
      * when the HPET wants to take over. Thus we have to disable the latter.
      */
     if (!no_hpet && (!kvm_irqchip_in_kernel() || kvm_has_pit_state2())) {
-        hpet = sysbus_try_create_simple("hpet", NULL, HPET_BASE, NULL);
+        hpet = sysbus_try_create_simple("hpet", hpet_intcap_set, HPET_BASE, 
NULL);
 
         if (hpet) {
             for (i = 0; i < GSI_NUM_PINS; i++) {
diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c
index 1139448..2e19ff5 100644
--- a/hw/timer/hpet.c
+++ b/hw/timer/hpet.c
@@ -25,6 +25,7 @@
  */
 
 #include "hw/hw.h"
+#include "hw/boards.h"
 #include "hw/i386/pc.h"
 #include "ui/console.h"
 #include "qemu/timer.h"
@@ -42,6 +43,11 @@
 
 #define HPET_MSI_SUPPORT        0
 
+/* only IRQ2 allowed for pc-1.6 and former */
+#define HPET_TN_INT_CAP_PC (0x4ULL << 32)
+/* Hpet can use non-legacy IRQ16~23, and an IRQ2 ,IRQ8 */
+#define HPET_TN_INT_CAP_DEFAULT 0xff0104ULL
+
 #define TYPE_HPET "hpet"
 #define HPET(obj) OBJECT_CHECK(HPETState, (obj), TYPE_HPET)
 
@@ -73,6 +79,7 @@ typedef struct HPETState {
     uint8_t rtc_irq_level;
     qemu_irq pit_enabled;
     uint8_t num_timers;
+    uint32_t intcap;
     HPETTimer timer[HPET_MAX_TIMERS];
 
     /* Memory-mapped, software visible registers */
@@ -663,8 +670,8 @@ static void hpet_reset(DeviceState *d)
         if (s->flags & (1 << HPET_MSI_SUPPORT)) {
             timer->config |= HPET_TN_FSB_CAP;
         }
-        /* advertise availability of ioapic inti2 */
-        timer->config |=  0x00000004ULL << 32;
+        /* advertise availability of ioapic int */
+        timer->config |=  (uint64_t)s->intcap << 32;
         timer->period = 0ULL;
         timer->wrap_flag = 0;
     }
@@ -753,6 +760,7 @@ static void hpet_realize(DeviceState *dev, Error **errp)
 static Property hpet_device_properties[] = {
     DEFINE_PROP_UINT8("timers", HPETState, num_timers, HPET_MIN_TIMERS),
     DEFINE_PROP_BIT("msi", HPETState, flags, HPET_MSI_SUPPORT, false),
+    DEFINE_PROP_UINT32("intcap", HPETState, intcap, HPET_TN_INT_CAP_DEFAULT),
     DEFINE_PROP_END_OF_LIST(),
 };
 
-- 
1.8.1.4