Use the acpi_{acquire,release}_global_lock() to implement the global

functionality for ACPI.  Has not shown any regressions, and may solve
some EC race conditions.

Ok gwk@, canacar@, ckuethe@

1 files changed, 40 insertions, 6 deletions

diff --git a/sys/dev/acpi/dsdt.c b/sys/dev/acpi/dsdt.c
index e3f38ea0094..9c5d8848186 100644
--- a/sys/dev/acpi/dsdt.c
+++ b/sys/dev/acpi/dsdt.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: dsdt.c,v 1.96 2007/11/03 21:13:48 ckuethe Exp $ */
+/* $OpenBSD: dsdt.c,v 1.97 2007/11/05 03:15:22 weingart Exp $ */
 /*
  * Copyright (c) 2005 Jordan Hargrave <jordan@openbsd.org>
  *
@@ -1025,20 +1025,54 @@ aml_getbufint(struct aml_value *src, int bitpos, int bitlen,
 	}
 }
 
+long acpi_acquire_global_lock(void*);
+long acpi_release_global_lock(void*);
+static long global_lock_count = 0;
+
 void
 aml_lockfield(struct aml_scope *scope, struct aml_value *field)
 {
-	if (AML_FIELD_LOCK(field->v_field.flags) == AML_FIELD_LOCK_ON) {
-		/* XXX: do locking here */
+	int st = 0;
+
+	if (AML_FIELD_LOCK(field->v_field.flags) != AML_FIELD_LOCK_ON)
+		return;
+
+	/* If lock is already ours, just continue */
+	if (global_lock_count++)
+		return;
+
+	/* Spin to acquire lock */
+	while (!st) {
+		st = acpi_acquire_global_lock(&dsdt_softc->sc_facs->global_lock);
+		/* XXX - yield/delay? */
 	}
+
+	return;
 }
 
 void
 aml_unlockfield(struct aml_scope *scope, struct aml_value *field)
 {
-	if (AML_FIELD_LOCK(field->v_field.flags) == AML_FIELD_LOCK_ON) {
-		/* XXX: do unlocking here */
-	}
+	int st, x;
+
+	if (AML_FIELD_LOCK(field->v_field.flags) != AML_FIELD_LOCK_ON)
+		return;
+
+	/* If we are the last ones, turn out the lights */
+	if (--global_lock_count)
+		return;
+
+	/* Release lock */
+	st = acpi_release_global_lock(&dsdt_softc->sc_facs->global_lock);
+	if (!st)
+		return;
+
+	/* Signal others if someone waiting */
+	x = acpi_read_pmreg(dsdt_softc, ACPIREG_PM1_CNT, 0);
+	x |= ACPI_PM1_GBL_RLS;
+	acpi_write_pmreg(dsdt_softc, ACPIREG_PM1_CNT, 0, x);
+
+	return;
 }
 
 void *aml_getbuffer(struct aml_value *, int *);