80 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			80 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| /*
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|  * Intel(R) Trace Hub data structures for implementing buffer sinks.
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|  *
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|  * Copyright (C) 2019 Intel Corporation.
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|  */
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| 
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| #ifndef _INTEL_TH_H_
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| #define _INTEL_TH_H_
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| 
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| #include <linux/scatterlist.h>
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| 
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| /* MSC operating modes (MSC_MODE) */
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| enum {
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| 	MSC_MODE_SINGLE	= 0,
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| 	MSC_MODE_MULTI,
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| 	MSC_MODE_EXI,
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| 	MSC_MODE_DEBUG,
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| };
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| 
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| struct msu_buffer {
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| 	const char	*name;
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| 	/*
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| 	 * ->assign() called when buffer 'mode' is set to this driver
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| 	 *   (aka mode_store())
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| 	 * @device:	struct device * of the msc
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| 	 * @mode:	allows the driver to set HW mode (see the enum above)
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| 	 * Returns:	a pointer to a private structure associated with this
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| 	 *		msc or NULL in case of error. This private structure
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| 	 *		will then be passed into all other callbacks.
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| 	 */
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| 	void	*(*assign)(struct device *dev, int *mode);
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| 	/* ->unassign():	some other mode is selected, clean up */
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| 	void	(*unassign)(void *priv);
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| 	/*
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| 	 * ->alloc_window(): allocate memory for the window of a given
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| 	 *		size
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| 	 * @sgt:	pointer to sg_table, can be overridden by the buffer
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| 	 *		driver, or kept intact
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| 	 * Returns:	number of sg table entries <= number of pages;
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| 	 *		0 is treated as an allocation failure.
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| 	 */
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| 	int	(*alloc_window)(void *priv, struct sg_table **sgt,
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| 				size_t size);
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| 	void	(*free_window)(void *priv, struct sg_table *sgt);
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| 	/* ->activate():	trace has started */
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| 	void	(*activate)(void *priv);
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| 	/* ->deactivate():	trace is about to stop */
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| 	void	(*deactivate)(void *priv);
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| 	/*
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| 	 * ->ready():	window @sgt is filled up to the last block OR
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| 	 *		tracing is stopped by the user; this window contains
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| 	 *		@bytes data. The window in question transitions into
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| 	 *		the "LOCKED" state, indicating that it can't be used
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| 	 *		by hardware. To clear this state and make the window
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| 	 *		available to the hardware again, call
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| 	 *		intel_th_msc_window_unlock().
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| 	 */
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| 	int	(*ready)(void *priv, struct sg_table *sgt, size_t bytes);
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| };
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| 
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| int intel_th_msu_buffer_register(const struct msu_buffer *mbuf,
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| 				 struct module *owner);
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| void intel_th_msu_buffer_unregister(const struct msu_buffer *mbuf);
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| void intel_th_msc_window_unlock(struct device *dev, struct sg_table *sgt);
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| 
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| #define module_intel_th_msu_buffer(__buffer) \
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| static int __init __buffer##_init(void) \
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| { \
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| 	return intel_th_msu_buffer_register(&(__buffer), THIS_MODULE); \
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| } \
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| module_init(__buffer##_init); \
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| static void __exit __buffer##_exit(void) \
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| { \
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| 	intel_th_msu_buffer_unregister(&(__buffer)); \
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| } \
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| module_exit(__buffer##_exit);
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| 
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| #endif /* _INTEL_TH_H_ */
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