acpigen: Add and use acpigen_write_device.

The sequence of bytes to create a method is used several times in codebase.
Put it into a function with logical arguments rather than duplicating magic
bytes everywhere.

Change-Id: I2c33fa403832eb1cfadfbf8d9adef5b63fb9cb24
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/7348
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Tested-by: build bot (Jenkins)

2 files changed, 14 insertions, 0 deletions

diff --git a/src/arch/x86/boot/acpigen.c b/src/arch/x86/boot/acpigen.c
index 0eee78a141..f714d5985b 100644
--- a/src/arch/x86/boot/acpigen.c
+++ b/src/arch/x86/boot/acpigen.c
@@ -408,6 +408,19 @@ int acpigen_write_method(const char *name, int nargs)
 	return len;
 }
 
+int acpigen_write_device(const char *name)
+{
+	int len;
+
+	/* method op */
+	len = acpigen_emit_byte(0x5b);
+	len += acpigen_emit_byte(0x82);
+	len += acpigen_write_len_f();
+	len += acpigen_emit_namestring(name);
+
+	return len;
+}
+
 /*
  * Generates a func with max supported P-states.
  */
diff --git a/src/arch/x86/include/arch/acpigen.h b/src/arch/x86/include/arch/acpigen.h
index babfb4014b..e07a0f5c22 100644
--- a/src/arch/x86/include/arch/acpigen.h
+++ b/src/arch/x86/include/arch/acpigen.h
@@ -44,6 +44,7 @@ int acpigen_write_name_qword(const char *name, uint64_t val);
 int acpigen_write_name_byte(const char *name, uint8_t val);
 int acpigen_write_scope(const char *name);
 int acpigen_write_method(const char *name, int nargs);
+int acpigen_write_device(const char *name);
 int acpigen_write_PPC(u8 nr);
 int acpigen_write_PPC_NVS(void);
 int acpigen_write_empty_PCT(void);