1 /*
2  * Copyright 2015 Martin Peres
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 COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Martin Peres
23  */
24 #include "priv.h"
25 
26 #include <subdev/volt.h>
27 #include <subdev/gpio.h>
28 #include <subdev/bios.h>
29 #include <subdev/bios/volt.h>
30 
31 #define gk104_volt(p) container_of((p), struct gk104_volt, base)
32 struct gk104_volt {
33 	struct nvkm_volt base;
34 	struct nvbios_volt bios;
35 };
36 
37 int
38 gk104_volt_get(struct nvkm_volt *base)
39 {
40 	struct nvbios_volt *bios = &gk104_volt(base)->bios;
41 	struct nvkm_device *device = base->subdev.device;
42 	u32 div, duty;
43 
44 	div  = nvkm_rd32(device, 0x20340);
45 	duty = nvkm_rd32(device, 0x20344);
46 
47 	return bios->base + bios->pwm_range * duty / div;
48 }
49 
50 int
51 gk104_volt_set(struct nvkm_volt *base, u32 uv)
52 {
53 	struct nvbios_volt *bios = &gk104_volt(base)->bios;
54 	struct nvkm_device *device = base->subdev.device;
55 	u32 div, duty;
56 
57 	/* the blob uses this crystal frequency, let's use it too. */
58 	div = 27648000 / bios->pwm_freq;
59 	duty = (uv - bios->base) * div / bios->pwm_range;
60 
61 	nvkm_wr32(device, 0x20340, div);
62 	nvkm_wr32(device, 0x20344, 0x8000000 | duty);
63 
64 	return 0;
65 }
66 
67 static const struct nvkm_volt_func
68 gk104_volt_pwm = {
69 	.volt_get = gk104_volt_get,
70 	.volt_set = gk104_volt_set,
71 }, gk104_volt_gpio = {
72 	.vid_get = nvkm_voltgpio_get,
73 	.vid_set = nvkm_voltgpio_set,
74 };
75 
76 int
77 gk104_volt_new(struct nvkm_device *device, int index, struct nvkm_volt **pvolt)
78 {
79 	const struct nvkm_volt_func *volt_func = &gk104_volt_gpio;
80 	struct dcb_gpio_func gpio;
81 	struct nvbios_volt bios;
82 	struct gk104_volt *volt;
83 	u8 ver, hdr, cnt, len;
84 	const char *mode;
85 
86 	if (!nvbios_volt_parse(device->bios, &ver, &hdr, &cnt, &len, &bios))
87 		return 0;
88 
89 	if (!nvkm_gpio_find(device->gpio, 0, DCB_GPIO_VID_PWM, 0xff, &gpio) &&
90 	    bios.type == NVBIOS_VOLT_PWM) {
91 		volt_func = &gk104_volt_pwm;
92 	}
93 
94 	if (!(volt = kzalloc(sizeof(*volt), GFP_KERNEL)))
95 		return -ENOMEM;
96 	nvkm_volt_ctor(volt_func, device, index, &volt->base);
97 	*pvolt = &volt->base;
98 	volt->bios = bios;
99 
100 	/* now that we have a subdev, we can show an error if we found through
101 	 * the voltage table that we were supposed to use the PWN mode but we
102 	 * did not find the right GPIO for it.
103 	 */
104 	if (bios.type == NVBIOS_VOLT_PWM && volt_func != &gk104_volt_pwm) {
105 		nvkm_error(&volt->base.subdev,
106 			   "Type mismatch between the voltage table type and "
107 			   "the GPIO table. Fallback to GPIO mode.\n");
108 	}
109 
110 	if (volt_func == &gk104_volt_gpio) {
111 		nvkm_voltgpio_init(&volt->base);
112 		mode = "GPIO";
113 	} else
114 		mode = "PWM";
115 
116 	nvkm_debug(&volt->base.subdev, "Using %s mode\n", mode);
117 
118 	return 0;
119 }
120