[linux-block.git] / include / linux / stm.h

// SPDX-License-Identifier: GPL-2.0
/*
 * System Trace Module (STM) infrastructure apis
 * Copyright (C) 2014 Intel Corporation.
 */

#ifndef _STM_H_
#define _STM_H_

#include <linux/device.h>

/**
 * enum stp_packet_type - STP packets that an STM driver sends
 */
enum stp_packet_type {
	STP_PACKET_DATA = 0,
	STP_PACKET_FLAG,
	STP_PACKET_USER,
	STP_PACKET_MERR,
	STP_PACKET_GERR,
	STP_PACKET_TRIG,
	STP_PACKET_XSYNC,
};

/**
 * enum stp_packet_flags - STP packet modifiers
 */
enum stp_packet_flags {
	STP_PACKET_MARKED	= 0x1,
	STP_PACKET_TIMESTAMPED	= 0x2,
};

/**
 * enum stm_source_type - STM source driver
 * @STM_USER: any STM trace source
 * @STM_FTRACE: ftrace STM source
 */
enum stm_source_type {
	STM_USER,
	STM_FTRACE,
};

struct stp_policy;

struct stm_device;

/**
 * struct stm_data - STM device description and callbacks
 * @name:		device name
 * @stm:		internal structure, only used by stm class code
 * @sw_start:		first STP master available to software
 * @sw_end:		last STP master available to software
 * @sw_nchannels:	number of STP channels per master
 * @sw_mmiosz:		size of one channel's IO space, for mmap, optional
 * @hw_override:	masters in the STP stream will not match the ones
 *			assigned by software, but are up to the STM hardware
 * @packet:		callback that sends an STP packet
 * @mmio_addr:		mmap callback, optional
 * @link:		called when a new stm_source gets linked to us, optional
 * @unlink:		likewise for unlinking, again optional
 * @set_options:	set device-specific options on a channel
 *
 * Fill out this structure before calling stm_register_device() to create
 * an STM device and stm_unregister_device() to destroy it. It will also be
 * passed back to @packet(), @mmio_addr(), @link(), @unlink() and @set_options()
 * callbacks.
 *
 * Normally, an STM device will have a range of masters available to software
 * and the rest being statically assigned to various hardware trace sources.
 * The former is defined by the range [@sw_start..@sw_end] of the device
 * description. That is, the lowest master that can be allocated to software
 * writers is @sw_start and data from this writer will appear is @sw_start
 * master in the STP stream.
 *
 * The @packet callback should adhere to the following rules:
 *   1) it must return the number of bytes it consumed from the payload;
 *   2) therefore, if it sent a packet that does not have payload (like FLAG),
 *      it must return zero;
 *   3) if it does not support the requested packet type/flag combination,
 *      it must return -ENOTSUPP.
 *
 * The @unlink callback is called when there are no more active writers so
 * that the master/channel can be quiesced.
 */
struct stm_data {
	const char		*name;
	struct stm_device	*stm;
	unsigned int		sw_start;
	unsigned int		sw_end;
	unsigned int		sw_nchannels;
	unsigned int		sw_mmiosz;
	unsigned int		hw_override;
	ssize_t			(*packet)(struct stm_data *, unsigned int,
					  unsigned int, unsigned int,
					  unsigned int, unsigned int,
					  const unsigned char *);
	phys_addr_t		(*mmio_addr)(struct stm_data *, unsigned int,
					     unsigned int, unsigned int);
	int			(*link)(struct stm_data *, unsigned int,
					unsigned int);
	void			(*unlink)(struct stm_data *, unsigned int,
					  unsigned int);
	long			(*set_options)(struct stm_data *, unsigned int,
					       unsigned int, unsigned int,
					       unsigned long);
};

int stm_register_device(struct device *parent, struct stm_data *stm_data,
			struct module *owner);
void stm_unregister_device(struct stm_data *stm_data);

struct stm_source_device;

/**
 * struct stm_source_data - STM source device description and callbacks
 * @name:	device name, will be used for policy lookup
 * @src:	internal structure, only used by stm class code
 * @nr_chans:	number of channels to allocate
 * @type:	type of STM source driver represented by stm_source_type
 * @link:	called when this source gets linked to an STM device
 * @unlink:	called when this source is about to get unlinked from its STM
 *
 * Fill in this structure before calling stm_source_register_device() to
 * register a source device. Also pass it to unregister and write calls.
 */
struct stm_source_data {
	const char		*name;
	struct stm_source_device *src;
	unsigned int		percpu;
	unsigned int		nr_chans;
	unsigned int		type;
	int			(*link)(struct stm_source_data *data);
	void			(*unlink)(struct stm_source_data *data);
};

int stm_source_register_device(struct device *parent,
			       struct stm_source_data *data);
void stm_source_unregister_device(struct stm_source_data *data);

int notrace stm_source_write(struct stm_source_data *data, unsigned int chan,
			     const char *buf, size_t count);

#endif /* _STM_H_ */
Commit	Line	Data
9ea393d8	1	// SPDX-License-Identifier: GPL-2.0
7bd1d409 AS	2	/*
	3	* System Trace Module (STM) infrastructure apis
	4	* Copyright (C) 2014 Intel Corporation.
7bd1d409 AS	5	*/
	6
	7	#ifndef _STM_H_
	8	#define _STM_H_
	9
	10	#include <linux/device.h>
	11
	12	/**
	13	* enum stp_packet_type - STP packets that an STM driver sends
	14	*/
	15	enum stp_packet_type {
	16	STP_PACKET_DATA = 0,
	17	STP_PACKET_FLAG,
	18	STP_PACKET_USER,
	19	STP_PACKET_MERR,
	20	STP_PACKET_GERR,
	21	STP_PACKET_TRIG,
	22	STP_PACKET_XSYNC,
	23	};
	24
	25	/**
	26	* enum stp_packet_flags - STP packet modifiers
	27	*/
	28	enum stp_packet_flags {
	29	STP_PACKET_MARKED = 0x1,
	30	STP_PACKET_TIMESTAMPED = 0x2,
	31	};
	32
07cf8356 ML	33	/**
	34	* enum stm_source_type - STM source driver
	35	* @STM_USER: any STM trace source
	36	* @STM_FTRACE: ftrace STM source
	37	*/
	38	enum stm_source_type {
	39	STM_USER,
	40	STM_FTRACE,
	41	};
	42
7bd1d409 AS	43	struct stp_policy;
	44
	45	struct stm_device;
	46
	47	/**
	48	* struct stm_data - STM device description and callbacks
	49	* @name: device name
	50	* @stm: internal structure, only used by stm class code
	51	* @sw_start: first STP master available to software
	52	* @sw_end: last STP master available to software
	53	* @sw_nchannels: number of STP channels per master
	54	* @sw_mmiosz: size of one channel's IO space, for mmap, optional
8e996a28 AS	55	* @hw_override: masters in the STP stream will not match the ones
8e996a28 AS	56	* assigned by software, but are up to the STM hardware
7bd1d409 AS	57	* @packet: callback that sends an STP packet
	58	* @mmio_addr: mmap callback, optional
	59	* @link: called when a new stm_source gets linked to us, optional
	60	* @unlink: likewise for unlinking, again optional
	61	* @set_options: set device-specific options on a channel
	62	*
	63	* Fill out this structure before calling stm_register_device() to create
	64	* an STM device and stm_unregister_device() to destroy it. It will also be
	65	* passed back to @packet(), @mmio_addr(), @link(), @unlink() and @set_options()
	66	* callbacks.
	67	*
	68	* Normally, an STM device will have a range of masters available to software
	69	* and the rest being statically assigned to various hardware trace sources.
d0b371e5	70	* The former is defined by the range [@sw_start..@sw_end] of the device
7bd1d409 AS	71	* description. That is, the lowest master that can be allocated to software
	72	* writers is @sw_start and data from this writer will appear is @sw_start
	73	* master in the STP stream.
f8560a9b AS	74	*
	75	* The @packet callback should adhere to the following rules:
	76	* 1) it must return the number of bytes it consumed from the payload;
	77	* 2) therefore, if it sent a packet that does not have payload (like FLAG),
	78	* it must return zero;
	79	* 3) if it does not support the requested packet type/flag combination,
	80	* it must return -ENOTSUPP.
cc842407 AS	81	*
	82	* The @unlink callback is called when there are no more active writers so
	83	* that the master/channel can be quiesced.
7bd1d409 AS	84	*/
	85	struct stm_data {
	86	const char *name;
	87	struct stm_device *stm;
	88	unsigned int sw_start;
	89	unsigned int sw_end;
	90	unsigned int sw_nchannels;
	91	unsigned int sw_mmiosz;
8e996a28	92	unsigned int hw_override;
7bd1d409 AS	93	ssize_t (packet)(struct stm_data , unsigned int,
	94	unsigned int, unsigned int,
	95	unsigned int, unsigned int,
	96	const unsigned char *);
	97	phys_addr_t (mmio_addr)(struct stm_data , unsigned int,
	98	unsigned int, unsigned int);
	99	int (link)(struct stm_data , unsigned int,
	100	unsigned int);
	101	void (unlink)(struct stm_data , unsigned int,
	102	unsigned int);
	103	long (set_options)(struct stm_data , unsigned int,
	104	unsigned int, unsigned int,
	105	unsigned long);
	106	};
	107
	108	int stm_register_device(struct device parent, struct stm_data stm_data,
	109	struct module *owner);
	110	void stm_unregister_device(struct stm_data *stm_data);
	111
	112	struct stm_source_device;
	113
	114	/**
	115	* struct stm_source_data - STM source device description and callbacks
	116	* @name: device name, will be used for policy lookup
	117	* @src: internal structure, only used by stm class code
	118	* @nr_chans: number of channels to allocate
07cf8356	119	* @type: type of STM source driver represented by stm_source_type
7bd1d409 AS	120	* @link: called when this source gets linked to an STM device
	121	* @unlink: called when this source is about to get unlinked from its STM
	122	*
	123	* Fill in this structure before calling stm_source_register_device() to
	124	* register a source device. Also pass it to unregister and write calls.
	125	*/
	126	struct stm_source_data {
	127	const char *name;
	128	struct stm_source_device *src;
	129	unsigned int percpu;
	130	unsigned int nr_chans;
07cf8356	131	unsigned int type;
7bd1d409 AS	132	int (link)(struct stm_source_data data);
	133	void (unlink)(struct stm_source_data data);
	134	};
	135
	136	int stm_source_register_device(struct device *parent,
	137	struct stm_source_data *data);
	138	void stm_source_unregister_device(struct stm_source_data *data);
	139
9dfed80d CZ	140	int notrace stm_source_write(struct stm_source_data *data, unsigned int chan,
9dfed80d CZ	141	const char *buf, size_t count);
7bd1d409 AS	142
7bd1d409 AS	143	#endif /* _STM_H_ */