Re: [Qemu-devel] [PATCH v5 2/5] hpet: entitle more irq pins for hpet

[Michael S. Tsirkin]

On Sun, Sep 29, 2013 at 11:49:41AM +0800, liu ping fan wrote:
> On Sun, Sep 29, 2013 at 3:56 AM, Michael S. Tsirkin <address@hidden> wrote:
> > On Thu, Sep 12, 2013 at 11:25:15AM +0800, Liu Ping Fan wrote:
> >> On PC, 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.
> >> (Will enable them after introducing pc 1.6 compat)
> >>
> >> Signed-off-by: Liu Ping Fan <address@hidden>
> >> ---
> >>  hw/timer/hpet.c | 13 +++++++++++--
> >>  1 file changed, 11 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c
> >> index 8429eb3..46903b9 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 +43,12 @@
> >>
> >>  #define HPET_MSI_SUPPORT        0
> >>
> >> +/* For bug compat, using only IRQ2. Soon it will be fixed as
> >> + * 0xff0104ULL, i.e using IRQ16~23, IRQ8 and IRQ2
> >
> > So users are expected to stick a bitmask of legal
> > pins here?
> > I think that's a bit too much rope to give to users.
> > Don't you think?
> >
> Sorry, not understand your meaning exactly.  But the scene will be:
> guest kernel polls the ability bitmask, and pick up one pin which is
> not occupied or can be shared with the level-trigger and low-active.
> So is it rope?

I merely say that it's better to make this a bool or bit property.
UINT32 is too much flexibility imho.

> Thanks and regards,
> Pingfan
> >> after
> >> + * introducing pc-1.6 compat.
> >> + */
> >> +#define HPET_TN_INT_CAP_DEFAULT 0x4ULL
> >> +
> >>  #define TYPE_HPET "hpet"
> >>  #define HPET(obj) OBJECT_CHECK(HPETState, (obj), TYPE_HPET)
> >>
> >> @@ -73,6 +80,7 @@ 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 +671,8 @@ 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 +761,7 @@ 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
> >>