cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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windfarm_pid.h (2734B)

      1/* SPDX-License-Identifier: GPL-2.0-only */
      2/*
      3 * Windfarm PowerMac thermal control. Generic PID helpers
      4 *
      5 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
      6 *                    <benh@kernel.crashing.org>
      7 *
      8 * This is a pair of generic PID helpers that can be used by
      9 * control loops. One is the basic PID implementation, the
     10 * other one is more specifically tailored to the loops used
     11 * for CPU control with 2 input sample types (temp and power)
     12 */
     13
     14/*
     15 * *** Simple PID ***
     16 */
     17
     18#define WF_PID_MAX_HISTORY	32
     19
     20/* This parameter array is passed to the PID algorithm. Currently,
     21 * we don't support changing parameters on the fly as it's not needed
     22 * but could be implemented (with necessary adjustment of the history
     23 * buffer
     24 */
     25struct wf_pid_param {
     26	int	interval;	/* Interval between samples in seconds */
     27	int	history_len;	/* Size of history buffer */
     28	int	additive;	/* 1: target relative to previous value */
     29	s32	gd, gp, gr;	/* PID gains */
     30	s32	itarget;	/* PID input target */
     31	s32	min,max;	/* min and max target values */
     32};
     33
     34struct wf_pid_state {
     35	int	first;				/* first run of the loop */
     36	int	index; 				/* index of current sample */
     37	s32	target;				/* current target value */
     38	s32	samples[WF_PID_MAX_HISTORY];	/* samples history buffer */
     39	s32	errors[WF_PID_MAX_HISTORY];	/* error history buffer */
     40
     41	struct wf_pid_param param;
     42};
     43
     44extern void wf_pid_init(struct wf_pid_state *st, struct wf_pid_param *param);
     45extern s32 wf_pid_run(struct wf_pid_state *st, s32 sample);
     46
     47
     48/*
     49 * *** CPU PID ***
     50 */
     51
     52#define WF_CPU_PID_MAX_HISTORY	32
     53
     54/* This parameter array is passed to the CPU PID algorithm. Currently,
     55 * we don't support changing parameters on the fly as it's not needed
     56 * but could be implemented (with necessary adjustment of the history
     57 * buffer
     58 */
     59struct wf_cpu_pid_param {
     60	int	interval;	/* Interval between samples in seconds */
     61	int	history_len;	/* Size of history buffer */
     62	s32	gd, gp, gr;	/* PID gains */
     63	s32	pmaxadj;	/* PID max power adjust */
     64	s32	ttarget;	/* PID input target */
     65	s32	tmax;		/* PID input max */
     66	s32	min,max;	/* min and max target values */
     67};
     68
     69struct wf_cpu_pid_state {
     70	int	first;				/* first run of the loop */
     71	int	index; 				/* index of current power */
     72	int	tindex; 			/* index of current temp */
     73	s32	target;				/* current target value */
     74	s32	last_delta;			/* last Tactual - Ttarget */
     75	s32	powers[WF_PID_MAX_HISTORY];	/* power history buffer */
     76	s32	errors[WF_PID_MAX_HISTORY];	/* error history buffer */
     77	s32	temps[2];			/* temp. history buffer */
     78
     79	struct wf_cpu_pid_param param;
     80};
     81
     82extern void wf_cpu_pid_init(struct wf_cpu_pid_state *st,
     83			    struct wf_cpu_pid_param *param);
     84extern s32 wf_cpu_pid_run(struct wf_cpu_pid_state *st, s32 power, s32 temp);