linux/drivers/clk/qcom/gdsc.h
Rajendra Nayak 77b1067a19 clk: qcom: gdsc: Add support for gdscs with gds hw controller
Some gdsc power domains can have a gds_hw_controller block inside
to help ensure all slave devices within the power domain are idle
before the gdsc is actually switched off.
This is mainly useful in power domains which host a MMU, in which
case its necessary to make sure there are no outstanding MMU operations
or pending bus transactions before the power domain is turned off.

In gdscs with gds_hw_controller block, its necessary to check the
gds_hw_ctrl status bits instead of the ones in gdscr, to determine
the state of the powerdomain.

While at it, also move away from using jiffies and use ktime APIs
instead for busy looping on status bits.

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-11 16:24:03 -08:00

78 lines
2.1 KiB
C

/*
* Copyright (c) 2015, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* 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.
*/
#ifndef __QCOM_GDSC_H__
#define __QCOM_GDSC_H__
#include <linux/err.h>
#include <linux/pm_domain.h>
struct regmap;
struct reset_controller_dev;
/* Powerdomain allowable state bitfields */
#define PWRSTS_OFF BIT(0)
#define PWRSTS_RET BIT(1)
#define PWRSTS_ON BIT(2)
#define PWRSTS_OFF_ON (PWRSTS_OFF | PWRSTS_ON)
#define PWRSTS_RET_ON (PWRSTS_RET | PWRSTS_ON)
/**
* struct gdsc - Globally Distributed Switch Controller
* @pd: generic power domain
* @regmap: regmap for MMIO accesses
* @gdscr: gsdc control register
* @gds_hw_ctrl: gds_hw_ctrl register
* @cxcs: offsets of branch registers to toggle mem/periph bits in
* @cxc_count: number of @cxcs
* @pwrsts: Possible powerdomain power states
* @resets: ids of resets associated with this gdsc
* @reset_count: number of @resets
* @rcdev: reset controller
*/
struct gdsc {
struct generic_pm_domain pd;
struct generic_pm_domain *parent;
struct regmap *regmap;
unsigned int gdscr;
unsigned int gds_hw_ctrl;
unsigned int *cxcs;
unsigned int cxc_count;
const u8 pwrsts;
struct reset_controller_dev *rcdev;
unsigned int *resets;
unsigned int reset_count;
};
struct gdsc_desc {
struct device *dev;
struct gdsc **scs;
size_t num;
};
#ifdef CONFIG_QCOM_GDSC
int gdsc_register(struct gdsc_desc *desc, struct reset_controller_dev *,
struct regmap *);
void gdsc_unregister(struct gdsc_desc *desc);
#else
static inline int gdsc_register(struct gdsc_desc *desc,
struct reset_controller_dev *rcdev,
struct regmap *r)
{
return -ENOSYS;
}
static inline void gdsc_unregister(struct gdsc_desc *desc) {};
#endif /* CONFIG_QCOM_GDSC */
#endif /* __QCOM_GDSC_H__ */