soc/intel/cannonlake: Add cannonlake ACPI GPIO op

Follow instrcution from https://doc.coreboot.org/acpi/gpio.html to
implement GPIO toggling method, covered for both CNP_LP and CNP_H pch.

BUG=N/A
TEST=Build and boot up fine on sarien platform, add an dummy STSX in
DSDT table, read back from iotools to confirm the GPIO tx state get
updated.

Signed-off-by: Lijian Zhao <lijian.zhao@intel.com>
Change-Id: I006a6a8fc580c73ac0938968397a628a4ffe504f
Reviewed-on: https://review.coreboot.org/c/30461
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/soc/intel/cannonlake/acpi.c b/src/soc/intel/cannonlake/acpi.c
index 84dfdad..4dab334 100644
--- a/src/soc/intel/cannonlake/acpi.c
+++ b/src/soc/intel/cannonlake/acpi.c
@@ -3,7 +3,7 @@
  *
  * Copyright (C) 2009 coresystems GmbH
  * Copyright (C) 2014 Google Inc.
- * Copyright (C) 2017 Intel Corporation.
+ * Copyright (C) 2017-2018 Intel Corporation.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -248,3 +248,40 @@
 {
 	return MP_IRQ_POLARITY_HIGH;
 }
+
+static int acpigen_soc_gpio_op(const char *op, unsigned int gpio_num)
+{
+	/* op (gpio_num) */
+	acpigen_emit_namestring(op);
+	acpigen_write_integer(gpio_num);
+	return 0;
+}
+
+static int acpigen_soc_get_gpio_state(const char *op, unsigned int gpio_num)
+{
+	/* Store (op (gpio_num), Local0) */
+	acpigen_write_store();
+	acpigen_soc_gpio_op(op, gpio_num);
+	acpigen_emit_byte(LOCAL0_OP);
+	return 0;
+}
+
+int acpigen_soc_read_rx_gpio(unsigned int gpio_num)
+{
+	return acpigen_soc_get_gpio_state("\\_SB.PCI0.GRXS", gpio_num);
+}
+
+int acpigen_soc_get_tx_gpio(unsigned int gpio_num)
+{
+	return acpigen_soc_get_gpio_state("\\_SB.PCI0.GTXS", gpio_num);
+}
+
+int acpigen_soc_set_tx_gpio(unsigned int gpio_num)
+{
+	return acpigen_soc_gpio_op("\\_SB.PCI0.STXS", gpio_num);
+}
+
+int acpigen_soc_clear_tx_gpio(unsigned int gpio_num)
+{
+	return acpigen_soc_gpio_op("\\_SB.PCI0.CTXS", gpio_num);
+}
diff --git a/src/soc/intel/cannonlake/acpi/gpio.asl b/src/soc/intel/cannonlake/acpi/gpio.asl
index e05cb68..1fa144f 100644
--- a/src/soc/intel/cannonlake/acpi/gpio.asl
+++ b/src/soc/intel/cannonlake/acpi/gpio.asl
@@ -2,7 +2,7 @@
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2014 Google Inc.
- * Copyright (C) 2015 Intel Corporation.
+ * Copyright (C) 2018 Intel Corporation.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -16,7 +16,7 @@
 #include <soc/gpio_defs.h>
 #include <soc/irq.h>
 #include <soc/pcr_ids.h>
-
+#include "gpio_op.asl"
 
 Device (GPIO)
 {
@@ -107,19 +107,3 @@
 	Add (Local2, PAD_CFG_BASE, Local2)
 	Return (Add (Local2, Multiply (Local1, 16)))
 }
-
-/*
- * Get GPIO Value
- * Arg0 - GPIO Number
- */
-Method (GRXS, 1, Serialized)
-{
-	OperationRegion (PREG, SystemMemory, GADD (Arg0), 4)
-	Field (PREG, AnyAcc, NoLock, Preserve)
-	{
-		VAL0, 32
-	}
-	And (GPIORXSTATE_MASK, ShiftRight (VAL0, GPIORXSTATE_SHIFT), Local0)
-
-	Return (Local0)
-}
diff --git a/src/soc/intel/cannonlake/acpi/gpio_cnp_h.asl b/src/soc/intel/cannonlake/acpi/gpio_cnp_h.asl
index e872b09..acbd2ea 100644
--- a/src/soc/intel/cannonlake/acpi/gpio_cnp_h.asl
+++ b/src/soc/intel/cannonlake/acpi/gpio_cnp_h.asl
@@ -15,7 +15,7 @@
 #include <soc/gpio_defs_cnp_h.h>
 #include <soc/irq.h>
 #include <soc/pcr_ids.h>
-
+#include "gpio_op.asl"
 
 Device (GPIO)
 {
@@ -107,19 +107,3 @@
 	Add (Local2, PAD_CFG_BASE, Local2)
 	Return (Add (Local2, Multiply (Local1, 16)))
 }
-
-/*
- * Get GPIO Value
- * Arg0 - GPIO Number
- */
-Method (GRXS, 1, Serialized)
-{
-	OperationRegion (PREG, SystemMemory, GADD (Arg0), 4)
-	Field (PREG, AnyAcc, NoLock, Preserve)
-	{
-		VAL0, 32
-	}
-	And (GPIORXSTATE_MASK, ShiftRight (VAL0, GPIORXSTATE_SHIFT), Local0)
-
-	Return (Local0)
-}
diff --git a/src/soc/intel/cannonlake/acpi/gpio_op.asl b/src/soc/intel/cannonlake/acpi/gpio_op.asl
new file mode 100644
index 0000000..0618601
--- /dev/null
+++ b/src/soc/intel/cannonlake/acpi/gpio_op.asl
@@ -0,0 +1,74 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2018 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+/*
+ * Get GPIO Value
+ * Arg0 - GPIO Number
+ */
+Method (GRXS, 1, Serialized)
+{
+	OperationRegion (PREG, SystemMemory, GADD (Arg0), 4)
+	Field (PREG, AnyAcc, NoLock, Preserve)
+	{
+		VAL0, 32
+	}
+	And (GPIORXSTATE_MASK, ShiftRight (VAL0, GPIORXSTATE_SHIFT), Local0)
+
+	Return (Local0)
+}
+
+/*
+ * Get GPIO Tx Value
+ * Arg0 - GPIO Number
+ */
+Method (GTXS, 1, Serialized)
+{
+	OperationRegion (PREG, SystemMemory, GADD (Arg0), 4)
+	Field (PREG, AnyAcc, NoLock, Preserve)
+	{
+		VAL0, 32
+	}
+	And (GPIOTXSTATE_MASK, VAL0, Local0)
+
+	Return (Local0)
+}
+
+/*
+ * Set GPIO Tx Value
+ * Arg0 - GPIO Number
+ */
+Method (STXS, 1, Serialized)
+{
+	OperationRegion (PREG, SystemMemory, GADD (Arg0), 4)
+	Field (PREG, AnyAcc, NoLock, Preserve)
+	{
+		VAL0, 32
+	}
+	Or (GPIOTXSTATE_MASK, VAL0, VAL0)
+}
+
+/*
+ * Clear GPIO Tx Value
+ * Arg0 - GPIO Number
+ */
+Method (CTXS, 1, Serialized)
+{
+	OperationRegion (PREG, SystemMemory, GADD (Arg0), 4)
+	Field (PREG, AnyAcc, NoLock, Preserve)
+	{
+		VAL0, 32
+	}
+	And (Not (GPIOTXSTATE_MASK), VAL0, VAL0)
+}
diff --git a/src/soc/intel/cannonlake/include/soc/gpio_defs.h b/src/soc/intel/cannonlake/include/soc/gpio_defs.h
index 716f59d..c282000 100644
--- a/src/soc/intel/cannonlake/include/soc/gpio_defs.h
+++ b/src/soc/intel/cannonlake/include/soc/gpio_defs.h
@@ -252,4 +252,5 @@
 
 #define GPIORXSTATE_MASK			0x1
 #define GPIORXSTATE_SHIFT			1
+#define GPIOTXSTATE_MASK			0x1
 #endif
diff --git a/src/soc/intel/cannonlake/include/soc/gpio_defs_cnp_h.h b/src/soc/intel/cannonlake/include/soc/gpio_defs_cnp_h.h
index ab04142..d8d002c 100644
--- a/src/soc/intel/cannonlake/include/soc/gpio_defs_cnp_h.h
+++ b/src/soc/intel/cannonlake/include/soc/gpio_defs_cnp_h.h
@@ -326,4 +326,5 @@
 
 #define GPIORXSTATE_MASK			0x1
 #define GPIORXSTATE_SHIFT			1
+#define GPIOTXSTATE_MASK			0x1
 #endif