From bb95002c2d47ab00764a183c200c7fd9ecb3c12a Mon Sep 17 00:00:00 2001
From: cinap_lenrek <cinap_lenrek@felloff.net>
Date: Sun, 2 Nov 2014 03:52:53 +0100
Subject: [PATCH] pc, pc64: implement acpi reset (for efi)

x230 booted in efi only (no csp) mode hangs
when traditional i8042reset() keyboard reset
is tried.

so we try acpireset() first which discoveres
and writes the acpi reset register.
---
 sys/src/9/pc/archacpi.c | 26 ++++++++++++++++++++++++++
 sys/src/9/pc/fns.h      |  1 +
 sys/src/9/pc/mp.c       |  1 +
 sys/src/9/pc64/fns.h    |  1 +
 4 files changed, 29 insertions(+)

diff --git a/sys/src/9/pc/archacpi.c b/sys/src/9/pc/archacpi.c
index f996d90df..a9482fc83 100644
--- a/sys/src/9/pc/archacpi.c
+++ b/sys/src/9/pc/archacpi.c
@@ -862,3 +862,29 @@ amldelay(int us)
 {
 	microdelay(us);
 }
+
+/*
+ * reset machine by writing acpi reset register.
+ */
+void
+acpireset(void)
+{
+	uchar *p;
+	Tbl *t;
+	int i;
+
+	for(i=0; i < ntblmap; i++){
+		t = tblmap[i];
+		if(memcmp(t->sig, "FACP", 4) != 0)
+			continue;
+		if(get32(t->len) <= 128)
+			break;
+		p = (uchar*)t;
+		if((get32(p + 112) & (1<<10)) == 0)
+			break;
+		if(p[116+0] != IoSpace)
+			break;
+		outb(get32(p+116+4), p[128]);
+		break;
+	}
+}
diff --git a/sys/src/9/pc/fns.h b/sys/src/9/pc/fns.h
index 8ecaa0f7d..93178a000 100644
--- a/sys/src/9/pc/fns.h
+++ b/sys/src/9/pc/fns.h
@@ -1,6 +1,7 @@
 #include "../port/portfns.h"
 
 void	aamloop(int);
+void	acpireset(void);
 Dirtab*	addarchfile(char*, int, long(*)(Chan*,void*,long,vlong), long(*)(Chan*,void*,long,vlong));
 void	archinit(void);
 int	bios32call(BIOS32ci*, u16int[3]);
diff --git a/sys/src/9/pc/mp.c b/sys/src/9/pc/mp.c
index 765fa30b6..63fe687fa 100644
--- a/sys/src/9/pc/mp.c
+++ b/sys/src/9/pc/mp.c
@@ -585,6 +585,7 @@ mpshutdown(void)
 	lapicicrw(0, 0x000C0000|ApicINIT);
 
 	pcireset();
+	acpireset();
 	i8042reset();
 
 	/*
diff --git a/sys/src/9/pc64/fns.h b/sys/src/9/pc64/fns.h
index fe67edded..15eb1a0f5 100644
--- a/sys/src/9/pc64/fns.h
+++ b/sys/src/9/pc64/fns.h
@@ -1,6 +1,7 @@
 #include "../port/portfns.h"
 
 void	aamloop(int);
+void	acpireset(void);
 Dirtab*	addarchfile(char*, int, long(*)(Chan*,void*,long,vlong), long(*)(Chan*,void*,long,vlong));
 void	archinit(void);
 int	bios32call(BIOS32ci*, u16int[3]);
-- 
2.44.0