e1000: Delay safe_pause switch until SI_SUB_CLOCKS

Based on sysinit_sub_id, SI_SUB_CLOCKS is after SI_SUB_CONFIGURE.

SI_SUB_CONFIGURE  = 0x3800000,  /* Configure devices */  
At this stage, the variable “cold” will be set to 0.

SI_SUB_CLOCKS    = 0x4800000,  /* real-time and stat clocks*/
At this stage, the clock configuration will be done, and the real-time
clock can be used.

In the e1000 driver, if the API safe_pause_* are called between
SI_SUB_CONFIGURE and SI_SUB_CLOCKS stages, it will choose the wrong
clock source. The API safe_pause_* uses “cold” the value of which is
updated in SI_SUB_CONFIGURE, to decide if the real-time clock source is
ready. However, the real-time clock is not ready til the SI_SUB_CLOCKS
routines are done.

Obtained from:	Juniper Networks
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D42920

2 files changed, 14 insertions, 2 deletions

diff --git a/sys/dev/e1000/e1000_osdep.c b/sys/dev/e1000/e1000_osdep.c
index 8016ee352068..8b598f18cf12 100644
--- a/sys/dev/e1000/e1000_osdep.c
+++ b/sys/dev/e1000/e1000_osdep.c
@@ -34,6 +34,16 @@
 
 #include "e1000_api.h"
 
+int e1000_use_pause_delay = 0;
+
+static void
+e1000_enable_pause_delay(void *use_pause_delay)
+{
+	*((int *)use_pause_delay) = 1;
+}
+
+SYSINIT(enable_pause_delay, SI_SUB_CLOCKS, SI_ORDER_ANY, e1000_enable_pause_delay, &e1000_use_pause_delay);
+
 /*
  * NOTE: the following routines using the e1000 
  * 	naming style are provided to the shared
diff --git a/sys/dev/e1000/e1000_osdep.h b/sys/dev/e1000/e1000_osdep.h
index bddb97afd8b9..893979025f01 100644
--- a/sys/dev/e1000/e1000_osdep.h
+++ b/sys/dev/e1000/e1000_osdep.h
@@ -79,9 +79,11 @@ ms_scale(int x) {
 	}
 }
 
+extern int e1000_use_pause_delay;
+
 static inline void
 safe_pause_us(int x) {
-	if (cold) {
+	if (!e1000_use_pause_delay) {
 		DELAY(x);
 	} else {
 		pause("e1000_delay", max(1,  x/(1000000/hz)));
@@ -90,7 +92,7 @@ safe_pause_us(int x) {
 
 static inline void
 safe_pause_ms(int x) {
-	if (cold) {
+	if (!e1000_use_pause_delay) {
 		DELAY(x*1000);
 	} else {
 		pause("e1000_delay", ms_scale(x));