340 lines
11 KiB
C
340 lines
11 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
|
/*
|
||
|
|
* Copyright (c) 2016, NVIDIA CORPORATION.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef _RESET_H
|
||
|
|
#define _RESET_H
|
||
|
|
|
||
|
|
#include <dm/ofnode.h>
|
||
|
|
#include <linux/errno.h>
|
||
|
|
|
||
|
|
/**
|
||
|
|
* A reset is a hardware signal indicating that a HW module (or IP block, or
|
||
|
|
* sometimes an entire off-CPU chip) reset all of its internal state to some
|
||
|
|
* known-good initial state. Drivers will often reset HW modules when they
|
||
|
|
* begin execution to ensure that hardware correctly responds to all requests,
|
||
|
|
* or in response to some error condition. Reset signals are often controlled
|
||
|
|
* externally to the HW module being reset, by an entity this API calls a reset
|
||
|
|
* controller. This API provides a standard means for drivers to request that
|
||
|
|
* reset controllers set or clear reset signals.
|
||
|
|
*
|
||
|
|
* A driver that implements UCLASS_RESET is a reset controller or provider. A
|
||
|
|
* controller will often implement multiple separate reset signals, since the
|
||
|
|
* hardware it manages often has this capability. reset-uclass.h describes the
|
||
|
|
* interface which reset controllers must implement.
|
||
|
|
*
|
||
|
|
* Reset consumers/clients are the HW modules affected by reset signals. This
|
||
|
|
* header file describes the API used by drivers for those HW modules.
|
||
|
|
*/
|
||
|
|
|
||
|
|
struct udevice;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* struct reset_ctl - A handle to (allowing control of) a single reset signal.
|
||
|
|
*
|
||
|
|
* Clients provide storage for reset control handles. The content of the
|
||
|
|
* structure is managed solely by the reset API and reset drivers. A reset
|
||
|
|
* control struct is initialized by "get"ing the reset control struct. The
|
||
|
|
* reset control struct is passed to all other reset APIs to identify which
|
||
|
|
* reset signal to operate upon.
|
||
|
|
*
|
||
|
|
* @dev: The device which implements the reset signal.
|
||
|
|
* @id: The reset signal ID within the provider.
|
||
|
|
* @data: An optional data field for scenarios where a single integer ID is not
|
||
|
|
* sufficient. If used, it can be populated through an .of_xlate op and
|
||
|
|
* processed during the various reset ops.
|
||
|
|
* @polarity: An optional polarity field for drivers that support
|
||
|
|
* different reset polarities.
|
||
|
|
*
|
||
|
|
* Should additional information to identify and configure any reset signal
|
||
|
|
* for any provider be required in the future, the struct could be expanded to
|
||
|
|
* either (a) add more fields to allow reset providers to store additional
|
||
|
|
* information, or (b) replace the id field with an opaque pointer, which the
|
||
|
|
* provider would dynamically allocated during its .of_xlate op, and process
|
||
|
|
* during is .request op. This may require the addition of an extra op to clean
|
||
|
|
* up the allocation.
|
||
|
|
*/
|
||
|
|
struct reset_ctl {
|
||
|
|
struct udevice *dev;
|
||
|
|
/*
|
||
|
|
* Written by of_xlate. In the future, we might add more fields here.
|
||
|
|
*/
|
||
|
|
unsigned long id;
|
||
|
|
unsigned long data;
|
||
|
|
unsigned long polarity;
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* struct reset_ctl_bulk - A handle to (allowing control of) a bulk of reset
|
||
|
|
* signals.
|
||
|
|
*
|
||
|
|
* Clients provide storage for the reset control bulk. The content of the
|
||
|
|
* structure is managed solely by the reset API. A reset control bulk struct is
|
||
|
|
* initialized by "get"ing the reset control bulk struct.
|
||
|
|
* The reset control bulk struct is passed to all other bulk reset APIs to apply
|
||
|
|
* the API to all the reset signals in the bulk struct.
|
||
|
|
*
|
||
|
|
* @resets: An array of reset signal handles handles.
|
||
|
|
* @count: The number of reset signal handles in the reset array.
|
||
|
|
*/
|
||
|
|
struct reset_ctl_bulk {
|
||
|
|
struct reset_ctl *resets;
|
||
|
|
unsigned int count;
|
||
|
|
};
|
||
|
|
|
||
|
|
#if CONFIG_IS_ENABLED(DM_RESET)
|
||
|
|
/**
|
||
|
|
* reset_get_by_index - Get/request a reset signal by integer index.
|
||
|
|
*
|
||
|
|
* This looks up and requests a reset signal. The index is relative to the
|
||
|
|
* client device; each device is assumed to have n reset signals associated
|
||
|
|
* with it somehow, and this function finds and requests one of them. The
|
||
|
|
* mapping of client device reset signal indices to provider reset signals may
|
||
|
|
* be via device-tree properties, board-provided mapping tables, or some other
|
||
|
|
* mechanism.
|
||
|
|
*
|
||
|
|
* @dev: The client device.
|
||
|
|
* @index: The index of the reset signal to request, within the client's
|
||
|
|
* list of reset signals.
|
||
|
|
* @reset_ctl A pointer to a reset control struct to initialize.
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_get_by_index(struct udevice *dev, int index,
|
||
|
|
struct reset_ctl *reset_ctl);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_get_by_index_nodev - Get/request a reset signal by integer index
|
||
|
|
* without a device.
|
||
|
|
*
|
||
|
|
* This is a version of reset_get_by_index() that does not use a device.
|
||
|
|
*
|
||
|
|
* @node: The client ofnode.
|
||
|
|
* @index: The index of the reset signal to request, within the client's
|
||
|
|
* list of reset signals.
|
||
|
|
* @reset_ctl A pointer to a reset control struct to initialize.
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_get_by_index_nodev(ofnode node, int index,
|
||
|
|
struct reset_ctl *reset_ctl);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_get_bulk - Get/request all reset signals of a device.
|
||
|
|
*
|
||
|
|
* This looks up and requests all reset signals of the client device; each
|
||
|
|
* device is assumed to have n reset signals associated with it somehow,
|
||
|
|
* and this function finds and requests all of them in a separate structure.
|
||
|
|
* The mapping of client device reset signals indices to provider reset signals
|
||
|
|
* may be via device-tree properties, board-provided mapping tables, or some
|
||
|
|
* other mechanism.
|
||
|
|
*
|
||
|
|
* @dev: The client device.
|
||
|
|
* @bulk A pointer to a reset control bulk struct to initialize.
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_get_bulk(struct udevice *dev, struct reset_ctl_bulk *bulk);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_get_by_name - Get/request a reset signal by name.
|
||
|
|
*
|
||
|
|
* This looks up and requests a reset signal. The name is relative to the
|
||
|
|
* client device; each device is assumed to have n reset signals associated
|
||
|
|
* with it somehow, and this function finds and requests one of them. The
|
||
|
|
* mapping of client device reset signal names to provider reset signal may be
|
||
|
|
* via device-tree properties, board-provided mapping tables, or some other
|
||
|
|
* mechanism.
|
||
|
|
*
|
||
|
|
* @dev: The client device.
|
||
|
|
* @name: The name of the reset signal to request, within the client's
|
||
|
|
* list of reset signals.
|
||
|
|
* @reset_ctl: A pointer to a reset control struct to initialize.
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_get_by_name(struct udevice *dev, const char *name,
|
||
|
|
struct reset_ctl *reset_ctl);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_request - Request a reset signal.
|
||
|
|
*
|
||
|
|
* @reset_ctl: A reset control struct.
|
||
|
|
*
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_request(struct reset_ctl *reset_ctl);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_free - Free a previously requested reset signal.
|
||
|
|
*
|
||
|
|
* @reset_ctl: A reset control struct that was previously successfully
|
||
|
|
* requested by reset_get_by_*().
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_free(struct reset_ctl *reset_ctl);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_assert - Assert a reset signal.
|
||
|
|
*
|
||
|
|
* This function will assert the specified reset signal, thus resetting the
|
||
|
|
* affected HW module(s). Depending on the reset controller hardware, the reset
|
||
|
|
* signal will either stay asserted until reset_deassert() is called, or the
|
||
|
|
* hardware may autonomously clear the reset signal itself.
|
||
|
|
*
|
||
|
|
* @reset_ctl: A reset control struct that was previously successfully
|
||
|
|
* requested by reset_get_by_*().
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_assert(struct reset_ctl *reset_ctl);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_assert_bulk - Assert all reset signals in a reset control bulk struct.
|
||
|
|
*
|
||
|
|
* This function will assert the specified reset signals in a reset control
|
||
|
|
* bulk struct, thus resetting the affected HW module(s). Depending on the
|
||
|
|
* reset controller hardware, the reset signals will either stay asserted
|
||
|
|
* until reset_deassert_bulk() is called, or the hardware may autonomously
|
||
|
|
* clear the reset signals itself.
|
||
|
|
*
|
||
|
|
* @bulk: A reset control bulk struct that was previously successfully
|
||
|
|
* requested by reset_get_bulk().
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_assert_bulk(struct reset_ctl_bulk *bulk);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_deassert - Deassert a reset signal.
|
||
|
|
*
|
||
|
|
* This function will deassert the specified reset signal, thus releasing the
|
||
|
|
* affected HW modules() from reset, and allowing them to continue normal
|
||
|
|
* operation.
|
||
|
|
*
|
||
|
|
* @reset_ctl: A reset control struct that was previously successfully
|
||
|
|
* requested by reset_get_by_*().
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_deassert(struct reset_ctl *reset_ctl);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_deassert_bulk - Deassert all reset signals in a reset control bulk
|
||
|
|
* struct.
|
||
|
|
*
|
||
|
|
* This function will deassert the specified reset signals in a reset control
|
||
|
|
* bulk struct, thus releasing the affected HW modules() from reset, and
|
||
|
|
* allowing them to continue normal operation.
|
||
|
|
*
|
||
|
|
* @bulk: A reset control bulk struct that was previously successfully
|
||
|
|
* requested by reset_get_bulk().
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_deassert_bulk(struct reset_ctl_bulk *bulk);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* rst_status - Check reset signal status.
|
||
|
|
*
|
||
|
|
* @reset_ctl: The reset signal to check.
|
||
|
|
* @return 0 if deasserted, positive if asserted, or a negative
|
||
|
|
* error code.
|
||
|
|
*/
|
||
|
|
int reset_status(struct reset_ctl *reset_ctl);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_release_all - Assert/Free an array of previously requested resets.
|
||
|
|
*
|
||
|
|
* For each reset contained in the reset array, this function will check if
|
||
|
|
* reset has been previously requested and then will assert and free it.
|
||
|
|
*
|
||
|
|
* @reset_ctl: A reset struct array that was previously successfully
|
||
|
|
* requested by reset_get_by_*().
|
||
|
|
* @count Number of reset contained in the array
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
int reset_release_all(struct reset_ctl *reset_ctl, int count);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_release_bulk - Assert/Free an array of previously requested reset
|
||
|
|
* signals in a reset control bulk struct.
|
||
|
|
*
|
||
|
|
* For each reset contained in the reset control bulk struct, this function
|
||
|
|
* will check if reset has been previously requested and then will assert
|
||
|
|
* and free it.
|
||
|
|
*
|
||
|
|
* @bulk: A reset control bulk struct that was previously successfully
|
||
|
|
* requested by reset_get_bulk().
|
||
|
|
* @return 0 if OK, or a negative error code.
|
||
|
|
*/
|
||
|
|
static inline int reset_release_bulk(struct reset_ctl_bulk *bulk)
|
||
|
|
{
|
||
|
|
return reset_release_all(bulk->resets, bulk->count);
|
||
|
|
}
|
||
|
|
#else
|
||
|
|
static inline int reset_get_by_index(struct udevice *dev, int index,
|
||
|
|
struct reset_ctl *reset_ctl)
|
||
|
|
{
|
||
|
|
return -ENOTSUPP;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_get_bulk(struct udevice *dev,
|
||
|
|
struct reset_ctl_bulk *bulk)
|
||
|
|
{
|
||
|
|
return -ENOTSUPP;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_get_by_name(struct udevice *dev, const char *name,
|
||
|
|
struct reset_ctl *reset_ctl)
|
||
|
|
{
|
||
|
|
return -ENOTSUPP;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_free(struct reset_ctl *reset_ctl)
|
||
|
|
{
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_assert(struct reset_ctl *reset_ctl)
|
||
|
|
{
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_assert_bulk(struct reset_ctl_bulk *bulk)
|
||
|
|
{
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_deassert(struct reset_ctl *reset_ctl)
|
||
|
|
{
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_deassert_bulk(struct reset_ctl_bulk *bulk)
|
||
|
|
{
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_status(struct reset_ctl *reset_ctl)
|
||
|
|
{
|
||
|
|
return -ENOTSUPP;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_release_all(struct reset_ctl *reset_ctl, int count)
|
||
|
|
{
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int reset_release_bulk(struct reset_ctl_bulk *bulk)
|
||
|
|
{
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/**
|
||
|
|
* reset_valid() - check if reset is valid
|
||
|
|
*
|
||
|
|
* @reset_ctl: the reset to check
|
||
|
|
* @return TRUE if valid, or FALSE
|
||
|
|
*/
|
||
|
|
static inline bool reset_valid(struct reset_ctl *reset_ctl)
|
||
|
|
{
|
||
|
|
return !!reset_ctl->dev;
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif
|