From: Keir Fraser <keir.fraser@citrix.com>
Date: Mon, 21 Jul 2008 08:46:17 +0000 (+0100)
Subject: x86: More accurate PIT frequency estimation (1193182Hz)
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~14171^2~15
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/success//%22http:/www.example.com/cgi/success/?a=commitdiff_plain;h=d84cb0723cbab44f52f553ca8769bd72b57325ed;p=xen.git

x86: More accurate PIT frequency estimation (1193182Hz)

In practice this has no impact since variance between crystals will be
substantially greater than 1-2ppm. But we may as well be as accurate
as possible.

From: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
---

diff --git a/xen/arch/x86/i8259.c b/xen/arch/x86/i8259.c
index 815e9e57f3..525bf1720e 100644
--- a/xen/arch/x86/i8259.c
+++ b/xen/arch/x86/i8259.c
@@ -411,7 +411,7 @@ void __init init_IRQ(void)
     apic_intr_init();
 
     /* Set the clock to HZ Hz */
-#define CLOCK_TICK_RATE 1193180 /* crystal freq (Hz) */
+#define CLOCK_TICK_RATE 1193182 /* crystal freq (Hz) */
 #define LATCH (((CLOCK_TICK_RATE)+(HZ/2))/HZ)
     outb_p(0x34, PIT_MODE);        /* binary, mode 2, LSB/MSB, ch 0 */
     outb_p(LATCH & 0xff, PIT_CH0); /* LSB */
diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c
index 24df5bcbe4..24bd8f8acb 100644
--- a/xen/arch/x86/time.c
+++ b/xen/arch/x86/time.c
@@ -214,7 +214,7 @@ static struct irqaction irq0 = { timer_interrupt, "timer", NULL };
  * Return processor ticks per second / CALIBRATE_FRAC.
  */
 
-#define CLOCK_TICK_RATE 1193180 /* system crystal frequency (Hz) */
+#define CLOCK_TICK_RATE 1193182 /* system crystal frequency (Hz) */
 #define CALIBRATE_FRAC  20      /* calibrate over 50ms */
 #define CALIBRATE_LATCH ((CLOCK_TICK_RATE+(CALIBRATE_FRAC/2))/CALIBRATE_FRAC)
 
diff --git a/xen/include/asm-x86/hvm/vpt.h b/xen/include/asm-x86/hvm/vpt.h
index db58653411..b43f5aea2e 100644
--- a/xen/include/asm-x86/hvm/vpt.h
+++ b/xen/include/asm-x86/hvm/vpt.h
@@ -95,7 +95,7 @@ struct periodic_time {
 };
 
 
-#define PIT_FREQ 1193181
+#define PIT_FREQ 1193182
 #define PIT_BASE 0x40
 
 typedef struct PITState {