[Patch v2 1/2] x86/vRTC: Make rtc_mode_{strict, no_ack} a per-domain option

[Andrew Cooper <andrew.cooper3@citrix.com>]

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Keir Fraser <keir@xen.org>
CC: Jan Beulich <JBeulich@suse.com>
CC: Tim Deegan <tim@xen.org>
---
 xen/arch/x86/hvm/hvm.c          |    4 ++++
 xen/arch/x86/hvm/rtc.c          |   21 ++++++++-------------
 xen/include/public/hvm/params.h |   11 ++++++++++-
 3 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index e2ba9de..06e52cb 100644
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -4116,6 +4116,10 @@ long do_hvm_op(unsigned long op, XEN_GUEST_HANDLE_PARAM(void) arg)
                 if ( a.value > SHUTDOWN_MAX )
                     rc = -EINVAL;
                 break;
+            case HVM_PARAM_RTC_MODE:
+                if ( a.value > 1 )
+                    rc = -EINVAL;
+                break;
             }
 
             if ( rc == 0 ) 
diff --git a/xen/arch/x86/hvm/rtc.c b/xen/arch/x86/hvm/rtc.c
index cdedefe..644a255 100644
--- a/xen/arch/x86/hvm/rtc.c
+++ b/xen/arch/x86/hvm/rtc.c
@@ -45,14 +45,9 @@
 #define epoch_year     1900
 #define get_year(x)    (x + epoch_year)
 
-enum rtc_mode {
-   rtc_mode_no_ack,
-   rtc_mode_strict
-};
-
-/* This must be in sync with how hvmloader sets the ACPI WAET flags. */
-#define mode_is(d, m) ((void)(d), rtc_mode_##m == rtc_mode_no_ack)
-#define rtc_mode_is(s, m) mode_is(vrtc_domain(s), m)
+#define rtc_mode_is(s, m) (                                        \
+        vrtc_domain(s)->arch.hvm_domain.params[HVM_PARAM_RTC_MODE] \
+                      == HVM_PARAM_RTC_MODE_ ## m)
 
 static void rtc_copy_date(RTCState *s);
 static void rtc_set_time(RTCState *s);
@@ -63,7 +58,7 @@ static void rtc_update_irq(RTCState *s)
 {
     ASSERT(spin_is_locked(&s->lock));
 
-    if ( rtc_mode_is(s, strict) && (s->hw.cmos_data[RTC_REG_C] & RTC_IRQF) )
+    if ( rtc_mode_is(s, STRICT) && (s->hw.cmos_data[RTC_REG_C] & RTC_IRQF) )
         return;
 
     /* IRQ is raised if any source is both raised & enabled */
@@ -73,7 +68,7 @@ static void rtc_update_irq(RTCState *s)
         return;
 
     s->hw.cmos_data[RTC_REG_C] |= RTC_IRQF;
-    if ( rtc_mode_is(s, no_ack) )
+    if ( rtc_mode_is(s, NO_ACK) )
         hvm_isa_irq_deassert(vrtc_domain(s), RTC_IRQ);
     hvm_isa_irq_assert(vrtc_domain(s), RTC_IRQ);
 }
@@ -84,8 +79,8 @@ bool_t rtc_periodic_interrupt(void *opaque)
     bool_t ret;
 
     spin_lock(&s->lock);
-    ret = rtc_mode_is(s, no_ack) || !(s->hw.cmos_data[RTC_REG_C] & RTC_IRQF);
-    if ( rtc_mode_is(s, no_ack) || !(s->hw.cmos_data[RTC_REG_C] & RTC_PF) )
+    ret = rtc_mode_is(s, NO_ACK) || !(s->hw.cmos_data[RTC_REG_C] & RTC_IRQF);
+    if ( rtc_mode_is(s, NO_ACK) || !(s->hw.cmos_data[RTC_REG_C] & RTC_PF) )
     {
         s->hw.cmos_data[RTC_REG_C] |= RTC_PF;
         rtc_update_irq(s);
@@ -647,7 +642,7 @@ static uint32_t rtc_ioport_read(RTCState *s, uint32_t addr)
     case RTC_REG_C:
         ret = s->hw.cmos_data[s->hw.cmos_index];
         s->hw.cmos_data[RTC_REG_C] = 0x00;
-        if ( (ret & RTC_IRQF) && !rtc_mode_is(s, no_ack) )
+        if ( (ret & RTC_IRQF) && !rtc_mode_is(s, NO_ACK) )
             hvm_isa_irq_deassert(d, RTC_IRQ);
         rtc_update_irq(s);
         check_update_timer(s);
diff --git a/xen/include/public/hvm/params.h b/xen/include/public/hvm/params.h
index 517a184..23289bd 100644
--- a/xen/include/public/hvm/params.h
+++ b/xen/include/public/hvm/params.h
@@ -145,6 +145,15 @@
 /* SHUTDOWN_* action in case of a triple fault */
 #define HVM_PARAM_TRIPLE_FAULT_REASON 31
 
-#define HVM_NR_PARAMS          32
+/*
+ * Domains RTC Mode, as informed in the WAET table.
+ * One of HVM_PARAM_RTC_MODE_*
+ */
+#define HVM_PARAM_RTC_MODE 32
+#define HVM_PARAM_RTC_MODE_STRICT 0 /* Normal behaviour */
+#define HVM_PARAM_RTC_MODE_NO_ACK 1 /* No need to ACK RegC */
+
+
+#define HVM_NR_PARAMS          33
 
 #endif /* __XEN_PUBLIC_HVM_PARAMS_H__ */
-- 
1.7.10.4