Files
OpenCellular/include/clock.h
Alec Berg 27e063ea10 lm4: Modified clock gating to allow easy expansion to low power.
Created a new function to enable or disable clocks to various
peripherals. This new function makes it easy to specify if you
want the clock enabled in run mode, sleep mode, and/or deep
sleep mode.

Added infrastructure to specify which GPIOs should interrupt the
EC from deep sleep.

BUG=none
BRANCH=none
TEST=Passes all unit tests. Ran on a peppy and verified that
the clock gate control registers in run mode (LM4_RCGC regs)
were the same before and after this change.

Change-Id: Ia5009ac8c837f61dca52fe86ebdeede2e1a7fe4d
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/172454
Reviewed-by: Randall Spangler <rspangler@chromium.org>
2013-10-10 23:14:20 +00:00

100 lines
3.0 KiB
C

/* Copyright (c) 2012 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.
*/
/* Clocks and power management settings */
#ifndef __CROS_EC_CLOCK_H
#define __CROS_EC_CLOCK_H
#include "common.h"
/**
* Set the CPU clocks and PLLs.
*/
void clock_init(void);
/**
* Return the current clock frequency in Hz.
*/
int clock_get_freq(void);
/**
* Enable or disable clock for a module.
*
* Note that if the module requires a higher system clock speed than the
* current system clock speed, the entire system clock will be increased
* to allow the module to operate.
*
* When a module is disabled, the system clock will be reduced to the highest
* clock required by the remaining enabled modules.
*
* @param module The module for which we need to enable/disable its
* clock.
* @param enable Enable clock if non-zero; disable if zero.
*/
void clock_enable_module(enum module_id module, int enable);
/**
* Enable or disable the PLL.
*
* @param enable Enable PLL if non-zero; disable if zero.
* @param notify Notify other modules of the PLL change. This should
* be 1 unless you're briefly turning on the PLL to work
* around a chip errata at init time.
*/
void clock_enable_pll(int enable, int notify);
/**
* Wait for a number of clock cycles.
*
* Simple busy waiting for use before clocks/timers are initialized.
*
* @param cycles Number of cycles to wait.
*/
void clock_wait_cycles(uint32_t cycles);
/* Low power modes for idle API */
enum {
SLEEP_MASK_AP_RUN = (1 << 0), /* the main CPU is running */
SLEEP_MASK_UART = (1 << 1), /* UART communication on-going */
SLEEP_MASK_I2C = (1 << 2), /* I2C master communication on-going */
SLEEP_MASK_CHARGING = (1 << 3), /* Charging loop on-going */
SLEEP_MASK_USB_PWR = (1 << 4), /* USB power loop on-going */
SLEEP_MASK_FORCE = (1 << 31), /* Force disabling low power modes */
};
/* Clock gate control modes for clock_enable_peripheral() */
#define CGC_MODE_RUN (1 << 0)
#define CGC_MODE_SLEEP (1 << 1)
#define CGC_MODE_DSLEEP (1 << 2)
#define CGC_MODE_ALL (CGC_MODE_RUN | CGC_MODE_SLEEP | CGC_MODE_DSLEEP)
/**
* Enable clock to peripheral by setting the CGC register pertaining
* to run, sleep, and/or deep sleep modes.
*
* @param offset Offset of the peripheral. See enum clock_gate_offsets.
* @param mask Bit mask of the bits within CGC reg to set.
* @param mode Which mode(s) to enable the clock for
*/
void clock_enable_peripheral(uint32_t offset, uint32_t mask, uint32_t mode);
/**
* Disable clock to peripheral by setting the CGC register pertaining
* to run, sleep, and/or deep sleep modes.
*
* @param offset Offset of the peripheral. See enum clock_gate_offsets.
* @param mask Bit mask of the bits within CGC reg to clear.
* @param mode Which mode(s) to enable the clock for
*/
void clock_disable_peripheral(uint32_t offset, uint32_t mask, uint32_t mode);
void enable_sleep(uint32_t mask);
void disable_sleep(uint32_t mask);
#endif /* __CROS_EC_CLOCK_H */