1 /*
2  * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
20  * DEALINGS IN THE SOFTWARE.
21  */
22 #define gk20a_pmu(p) container_of((p), struct gk20a_pmu, base)
23 #include "priv.h"
24 
25 #include <subdev/clk.h>
26 #include <subdev/timer.h>
27 #include <subdev/volt.h>
28 
29 #define BUSY_SLOT	0
30 #define CLK_SLOT	7
31 
32 struct gk20a_pmu_dvfs_data {
33 	int p_load_target;
34 	int p_load_max;
35 	int p_smooth;
36 	unsigned int avg_load;
37 };
38 
39 struct gk20a_pmu {
40 	struct nvkm_pmu base;
41 	struct nvkm_alarm alarm;
42 	struct gk20a_pmu_dvfs_data *data;
43 };
44 
45 struct gk20a_pmu_dvfs_dev_status {
46 	u32 total;
47 	u32 busy;
48 };
49 
50 static int
51 gk20a_pmu_dvfs_target(struct gk20a_pmu *pmu, int *state)
52 {
53 	struct nvkm_clk *clk = pmu->base.subdev.device->clk;
54 
55 	return nvkm_clk_astate(clk, *state, 0, false);
56 }
57 
58 static void
59 gk20a_pmu_dvfs_get_cur_state(struct gk20a_pmu *pmu, int *state)
60 {
61 	struct nvkm_clk *clk = pmu->base.subdev.device->clk;
62 
63 	*state = clk->pstate;
64 }
65 
66 static int
67 gk20a_pmu_dvfs_get_target_state(struct gk20a_pmu *pmu,
68 				int *state, int load)
69 {
70 	struct gk20a_pmu_dvfs_data *data = pmu->data;
71 	struct nvkm_clk *clk = pmu->base.subdev.device->clk;
72 	int cur_level, level;
73 
74 	/* For GK20A, the performance level is directly mapped to pstate */
75 	level = cur_level = clk->pstate;
76 
77 	if (load > data->p_load_max) {
78 		level = min(clk->state_nr - 1, level + (clk->state_nr / 3));
79 	} else {
80 		level += ((load - data->p_load_target) * 10 /
81 				data->p_load_target) / 2;
82 		level = max(0, level);
83 		level = min(clk->state_nr - 1, level);
84 	}
85 
86 	nvkm_trace(&pmu->base.subdev, "cur level = %d, new level = %d\n",
87 		   cur_level, level);
88 
89 	*state = level;
90 
91 	return (level != cur_level);
92 }
93 
94 static void
95 gk20a_pmu_dvfs_get_dev_status(struct gk20a_pmu *pmu,
96 			      struct gk20a_pmu_dvfs_dev_status *status)
97 {
98 	struct nvkm_falcon *falcon = &pmu->base.falcon;
99 
100 	status->busy = nvkm_falcon_rd32(falcon, 0x508 + (BUSY_SLOT * 0x10));
101 	status->total= nvkm_falcon_rd32(falcon, 0x508 + (CLK_SLOT * 0x10));
102 }
103 
104 static void
105 gk20a_pmu_dvfs_reset_dev_status(struct gk20a_pmu *pmu)
106 {
107 	struct nvkm_falcon *falcon = &pmu->base.falcon;
108 
109 	nvkm_falcon_wr32(falcon, 0x508 + (BUSY_SLOT * 0x10), 0x80000000);
110 	nvkm_falcon_wr32(falcon, 0x508 + (CLK_SLOT * 0x10), 0x80000000);
111 }
112 
113 static void
114 gk20a_pmu_dvfs_work(struct nvkm_alarm *alarm)
115 {
116 	struct gk20a_pmu *pmu =
117 		container_of(alarm, struct gk20a_pmu, alarm);
118 	struct gk20a_pmu_dvfs_data *data = pmu->data;
119 	struct gk20a_pmu_dvfs_dev_status status;
120 	struct nvkm_subdev *subdev = &pmu->base.subdev;
121 	struct nvkm_device *device = subdev->device;
122 	struct nvkm_clk *clk = device->clk;
123 	struct nvkm_timer *tmr = device->timer;
124 	struct nvkm_volt *volt = device->volt;
125 	u32 utilization = 0;
126 	int state;
127 
128 	/*
129 	 * The PMU is initialized before CLK and VOLT, so we have to make sure the
130 	 * CLK and VOLT are ready here.
131 	 */
132 	if (!clk || !volt)
133 		goto resched;
134 
135 	gk20a_pmu_dvfs_get_dev_status(pmu, &status);
136 
137 	if (status.total)
138 		utilization = div_u64((u64)status.busy * 100, status.total);
139 
140 	data->avg_load = (data->p_smooth * data->avg_load) + utilization;
141 	data->avg_load /= data->p_smooth + 1;
142 	nvkm_trace(subdev, "utilization = %d %%, avg_load = %d %%\n",
143 		   utilization, data->avg_load);
144 
145 	gk20a_pmu_dvfs_get_cur_state(pmu, &state);
146 
147 	if (gk20a_pmu_dvfs_get_target_state(pmu, &state, data->avg_load)) {
148 		nvkm_trace(subdev, "set new state to %d\n", state);
149 		gk20a_pmu_dvfs_target(pmu, &state);
150 	}
151 
152 resched:
153 	gk20a_pmu_dvfs_reset_dev_status(pmu);
154 	nvkm_timer_alarm(tmr, 100000000, alarm);
155 }
156 
157 static void
158 gk20a_pmu_fini(struct nvkm_pmu *pmu)
159 {
160 	struct gk20a_pmu *gpmu = gk20a_pmu(pmu);
161 	nvkm_timer_alarm(pmu->subdev.device->timer, 0, &gpmu->alarm);
162 
163 	nvkm_falcon_put(&pmu->falcon, &pmu->subdev);
164 }
165 
166 static int
167 gk20a_pmu_init(struct nvkm_pmu *pmu)
168 {
169 	struct gk20a_pmu *gpmu = gk20a_pmu(pmu);
170 	struct nvkm_subdev *subdev = &pmu->subdev;
171 	struct nvkm_device *device = pmu->subdev.device;
172 	struct nvkm_falcon *falcon = &pmu->falcon;
173 	int ret;
174 
175 	ret = nvkm_falcon_get(falcon, subdev);
176 	if (ret) {
177 		nvkm_error(subdev, "cannot acquire %s falcon!\n", falcon->name);
178 		return ret;
179 	}
180 
181 	/* init pwr perf counter */
182 	nvkm_falcon_wr32(falcon, 0x504 + (BUSY_SLOT * 0x10), 0x00200001);
183 	nvkm_falcon_wr32(falcon, 0x50c + (BUSY_SLOT * 0x10), 0x00000002);
184 	nvkm_falcon_wr32(falcon, 0x50c + (CLK_SLOT * 0x10), 0x00000003);
185 
186 	nvkm_timer_alarm(device->timer, 2000000000, &gpmu->alarm);
187 	return 0;
188 }
189 
190 static struct gk20a_pmu_dvfs_data
191 gk20a_dvfs_data= {
192 	.p_load_target = 70,
193 	.p_load_max = 90,
194 	.p_smooth = 1,
195 };
196 
197 static const struct nvkm_pmu_func
198 gk20a_pmu = {
199 	.flcn = &gt215_pmu_flcn,
200 	.enabled = gf100_pmu_enabled,
201 	.init = gk20a_pmu_init,
202 	.fini = gk20a_pmu_fini,
203 	.reset = gf100_pmu_reset,
204 };
205 
206 static const struct nvkm_pmu_fwif
207 gk20a_pmu_fwif[] = {
208 	{ -1, gf100_pmu_nofw, &gk20a_pmu },
209 	{}
210 };
211 
212 int
213 gk20a_pmu_new(struct nvkm_device *device, enum nvkm_subdev_type type, int inst,
214 	      struct nvkm_pmu **ppmu)
215 {
216 	struct gk20a_pmu *pmu;
217 	int ret;
218 
219 	if (!(pmu = kzalloc(sizeof(*pmu), GFP_KERNEL)))
220 		return -ENOMEM;
221 	*ppmu = &pmu->base;
222 
223 	ret = nvkm_pmu_ctor(gk20a_pmu_fwif, device, type, inst, &pmu->base);
224 	if (ret)
225 		return ret;
226 
227 	pmu->data = &gk20a_dvfs_data;
228 	nvkm_alarm_init(&pmu->alarm, gk20a_pmu_dvfs_work);
229 	return 0;
230 }
231