mec1322: initial commit

This is the initial commit of mec1322 support. This includes:
  - Basic GPIO driver. Interrupt not supported yet.
  - Microsecond timer
  - UART driver

The script to pack the firmware binary will be checked in in
following-up CL.

BUG=chrome-os-partner:24107
TEST=Build and boot on eval board
BRANCH=None

Change-Id: I9013c908049d1f740f84bb56abca51b779f39eef
Signed-off-by: Vic (Chun-Ju) Yang <victoryang@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/175716
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>

1 files changed, 116 insertions, 0 deletions

diff --git a/chip/mec1322/gpio.c b/chip/mec1322/gpio.c
new file mode 100644
index 0000000000..065b4383ec
--- /dev/null
+++ b/chip/mec1322/gpio.c
@@ -0,0 +1,116 @@
+/* Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/* GPIO module for MEC1322 */
+
+#include "common.h"
+#include "gpio.h"
+#include "registers.h"
+#include "timer.h"
+#include "util.h"
+
+void gpio_set_alternate_function(uint32_t port, uint32_t mask, int func)
+{
+	int i;
+	uint32_t val;
+
+	while (mask) {
+		i = __builtin_ffs(mask) - 1;
+		val = MEC1322_GPIO_CTL(port, i);
+		val &= ~((1 << 12) | (1 << 13));
+		val |= (func & 0x3) << 12;
+		MEC1322_GPIO_CTL(port, i) = val;
+		mask &= ~(1 << i);
+	}
+}
+
+test_mockable int gpio_get_level(enum gpio_signal signal)
+{
+	uint32_t mask = gpio_list[signal].mask;
+	int i = 31 - __builtin_clz(mask);
+	uint32_t val = MEC1322_GPIO_CTL(gpio_list[signal].port, i);
+
+	if (val & (1 << 9)) /* Output */
+		return (val & (1 << 16)) ? 1 : 0;
+	else
+		return (val & (1 << 24)) ? 1 : 0;
+}
+
+void gpio_set_level(enum gpio_signal signal, int value)
+{
+	uint32_t mask = gpio_list[signal].mask;
+	int i = 31 - __builtin_clz(mask);
+	if (value)
+		MEC1322_GPIO_CTL(gpio_list[signal].port, i) |= (1 << 16);
+	else
+		MEC1322_GPIO_CTL(gpio_list[signal].port, i) &= ~(1 << 16);
+}
+
+void gpio_set_flags_by_mask(uint32_t port, uint32_t mask, uint32_t flags)
+{
+	int i;
+	uint32_t val;
+	while (mask) {
+		i = 31 - __builtin_clz(mask);
+		mask &= ~(1 << i);
+		val = MEC1322_GPIO_CTL(port, i);
+
+		/*
+		 * Select open drain first, so that we don't glitch the signal
+		 * when changing the line to an output.
+		 */
+		if (flags & GPIO_OPEN_DRAIN)
+			val |= (1 << 8);
+		else
+			val &= ~(1 << 8);
+
+		if (flags & GPIO_OUTPUT) {
+			val |= (1 << 9);
+			val &= ~(1 << 10);
+		} else {
+			val &= ~(1 << 9);
+			val |= (1 << 10);
+		}
+
+		/* Handle pullup / pulldown */
+		if (flags & GPIO_PULL_UP)
+			val = (val & ~0x3) | 0x1;
+		else if (flags & GPIO_PULL_DOWN)
+			val = (val & ~0x3) | 0x2;
+		else
+			val &= ~0x3;
+
+		/* TODO(crosbug.com/p/24107): Set up interrupt */
+
+		/* Use as GPIO */
+		val &= ~((1 << 12) | (1 << 13));
+
+		MEC1322_GPIO_CTL(port, i) = val;
+
+		if (flags & GPIO_HIGH)
+			MEC1322_GPIO_CTL(port, i) |= (1 << 16);
+		else
+			MEC1322_GPIO_CTL(port, i) &= ~(1 << 16);
+	}
+}
+
+int gpio_enable_interrupt(enum gpio_signal signal)
+{
+	return EC_ERROR_UNIMPLEMENTED;
+}
+
+int gpio_disable_interrupt(enum gpio_signal signal)
+{
+	return EC_ERROR_UNIMPLEMENTED;
+}
+
+void gpio_pre_init(void)
+{
+	int i;
+	const struct gpio_info *g = gpio_list;
+
+	for (i = 0; i < GPIO_COUNT; i++, g++)
+		gpio_set_flags_by_mask(g->port, g->mask, g->flags);
+}