1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2/*
3 * Copyright (c) 2019, Mellanox Technologies inc.  All rights reserved.
4 */
5
6#include <linux/dim.h>
7
8bool dim_on_top(struct dim *dim)
9{
10	switch (dim->tune_state) {
11	case DIM_PARKING_ON_TOP:
12	case DIM_PARKING_TIRED:
13		return true;
14	case DIM_GOING_RIGHT:
15		return (dim->steps_left > 1) && (dim->steps_right == 1);
16	default: /* DIM_GOING_LEFT */
17		return (dim->steps_right > 1) && (dim->steps_left == 1);
18	}
19}
20EXPORT_SYMBOL(dim_on_top);
21
22void dim_turn(struct dim *dim)
23{
24	switch (dim->tune_state) {
25	case DIM_PARKING_ON_TOP:
26	case DIM_PARKING_TIRED:
27		break;
28	case DIM_GOING_RIGHT:
29		dim->tune_state = DIM_GOING_LEFT;
30		dim->steps_left = 0;
31		break;
32	case DIM_GOING_LEFT:
33		dim->tune_state = DIM_GOING_RIGHT;
34		dim->steps_right = 0;
35		break;
36	}
37}
38EXPORT_SYMBOL(dim_turn);
39
40void dim_park_on_top(struct dim *dim)
41{
42	dim->steps_right  = 0;
43	dim->steps_left   = 0;
44	dim->tired        = 0;
45	dim->tune_state   = DIM_PARKING_ON_TOP;
46}
47EXPORT_SYMBOL(dim_park_on_top);
48
49void dim_park_tired(struct dim *dim)
50{
51	dim->steps_right  = 0;
52	dim->steps_left   = 0;
53	dim->tune_state   = DIM_PARKING_TIRED;
54}
55EXPORT_SYMBOL(dim_park_tired);
56
57bool dim_calc_stats(struct dim_sample *start, struct dim_sample *end,
58		    struct dim_stats *curr_stats)
59{
60	/* u32 holds up to 71 minutes, should be enough */
61	u32 delta_us = ktime_us_delta(end->time, start->time);
62	u32 npkts = BIT_GAP(BITS_PER_TYPE(u32), end->pkt_ctr, start->pkt_ctr);
63	u32 nbytes = BIT_GAP(BITS_PER_TYPE(u32), end->byte_ctr,
64			     start->byte_ctr);
65	u32 ncomps = BIT_GAP(BITS_PER_TYPE(u32), end->comp_ctr,
66			     start->comp_ctr);
67
68	if (!delta_us)
69		return false;
70
71	curr_stats->ppms = DIV_ROUND_UP(npkts * USEC_PER_MSEC, delta_us);
72	curr_stats->bpms = DIV_ROUND_UP(nbytes * USEC_PER_MSEC, delta_us);
73	curr_stats->epms = DIV_ROUND_UP(DIM_NEVENTS * USEC_PER_MSEC,
74					delta_us);
75	curr_stats->cpms = DIV_ROUND_UP(ncomps * USEC_PER_MSEC, delta_us);
76	if (curr_stats->epms != 0)
77		curr_stats->cpe_ratio = DIV_ROUND_DOWN_ULL(
78			curr_stats->cpms * 100, curr_stats->epms);
79	else
80		curr_stats->cpe_ratio = 0;
81
82	return true;
83}
84EXPORT_SYMBOL(dim_calc_stats);
85