xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/amd/display/dc/gpio/amdgpu_hw_gpio.c (revision 0caae2224fa2e443b0194fe793325afc8e00f306)
1 /*	$NetBSD: amdgpu_hw_gpio.c,v 1.3 2021/12/19 12:02:39 riastradh Exp $	*/
2 
3 /*
4  * Copyright 2012-15 Advanced Micro Devices, Inc.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  *
24  * Authors: AMD
25  *
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: amdgpu_hw_gpio.c,v 1.3 2021/12/19 12:02:39 riastradh Exp $");
30 
31 #include "dm_services.h"
32 #include "include/gpio_types.h"
33 #include "hw_gpio.h"
34 
35 #include "reg_helper.h"
36 #include "gpio_regs.h"
37 
38 #undef FN
39 #define FN(reg_name, field_name) \
40 	gpio->regs->field_name ## _shift, gpio->regs->field_name ## _mask
41 
42 #define CTX \
43 	gpio->base.ctx
44 #define REG(reg)\
45 	(gpio->regs->reg)
46 
store_registers(struct hw_gpio * gpio)47 static void store_registers(
48 	struct hw_gpio *gpio)
49 {
50 	REG_GET(MASK_reg, MASK, &gpio->store.mask);
51 	REG_GET(A_reg, A, &gpio->store.a);
52 	REG_GET(EN_reg, EN, &gpio->store.en);
53 	/* TODO store GPIO_MUX_CONTROL if we ever use it */
54 }
55 
restore_registers(struct hw_gpio * gpio)56 static void restore_registers(
57 	struct hw_gpio *gpio)
58 {
59 	REG_UPDATE(MASK_reg, MASK, gpio->store.mask);
60 	REG_UPDATE(A_reg, A, gpio->store.a);
61 	REG_UPDATE(EN_reg, EN, gpio->store.en);
62 	/* TODO restore GPIO_MUX_CONTROL if we ever use it */
63 }
64 
dal_hw_gpio_open(struct hw_gpio_pin * ptr,enum gpio_mode mode)65 bool dal_hw_gpio_open(
66 	struct hw_gpio_pin *ptr,
67 	enum gpio_mode mode)
68 {
69 	struct hw_gpio *pin = FROM_HW_GPIO_PIN(ptr);
70 
71 	store_registers(pin);
72 
73 	ptr->opened = (dal_hw_gpio_config_mode(pin, mode) == GPIO_RESULT_OK);
74 
75 	return ptr->opened;
76 }
77 
dal_hw_gpio_get_value(const struct hw_gpio_pin * ptr,uint32_t * value)78 enum gpio_result dal_hw_gpio_get_value(
79 	const struct hw_gpio_pin *ptr,
80 	uint32_t *value)
81 {
82 	const struct hw_gpio *gpio = const_container_of(ptr, struct hw_gpio, base);
83 
84 	enum gpio_result result = GPIO_RESULT_OK;
85 
86 	switch (ptr->mode) {
87 	case GPIO_MODE_INPUT:
88 	case GPIO_MODE_OUTPUT:
89 	case GPIO_MODE_HARDWARE:
90 	case GPIO_MODE_FAST_OUTPUT:
91 		REG_GET(Y_reg, Y, value);
92 		break;
93 	default:
94 		result = GPIO_RESULT_NON_SPECIFIC_ERROR;
95 	}
96 
97 	return result;
98 }
99 
dal_hw_gpio_set_value(const struct hw_gpio_pin * ptr,uint32_t value)100 enum gpio_result dal_hw_gpio_set_value(
101 	const struct hw_gpio_pin *ptr,
102 	uint32_t value)
103 {
104 	const struct hw_gpio *gpio = const_container_of(ptr, struct hw_gpio, base);
105 
106 	/* This is the public interface
107 	 * where the input comes from client, not shifted yet
108 	 * (because client does not know the shifts). */
109 
110 	switch (ptr->mode) {
111 	case GPIO_MODE_OUTPUT:
112 		REG_UPDATE(A_reg, A, value);
113 		return GPIO_RESULT_OK;
114 	case GPIO_MODE_FAST_OUTPUT:
115 		/* We use (EN) to faster switch (used in DDC GPIO).
116 		 * So (A) is grounded, output is driven by (EN = 0)
117 		 * to pull the line down (output == 0) and (EN=1)
118 		 * then output is tri-state */
119 		REG_UPDATE(EN_reg, EN, ~value);
120 		return GPIO_RESULT_OK;
121 	default:
122 		return GPIO_RESULT_NON_SPECIFIC_ERROR;
123 	}
124 }
125 
dal_hw_gpio_change_mode(struct hw_gpio_pin * ptr,enum gpio_mode mode)126 enum gpio_result dal_hw_gpio_change_mode(
127 	struct hw_gpio_pin *ptr,
128 	enum gpio_mode mode)
129 {
130 	struct hw_gpio *pin = FROM_HW_GPIO_PIN(ptr);
131 
132 	return dal_hw_gpio_config_mode(pin, mode);
133 }
134 
dal_hw_gpio_close(struct hw_gpio_pin * ptr)135 void dal_hw_gpio_close(
136 	struct hw_gpio_pin *ptr)
137 {
138 	struct hw_gpio *pin = FROM_HW_GPIO_PIN(ptr);
139 
140 	restore_registers(pin);
141 
142 	ptr->mode = GPIO_MODE_UNKNOWN;
143 	ptr->opened = false;
144 }
145 
dal_hw_gpio_config_mode(struct hw_gpio * gpio,enum gpio_mode mode)146 enum gpio_result dal_hw_gpio_config_mode(
147 	struct hw_gpio *gpio,
148 	enum gpio_mode mode)
149 {
150 	gpio->base.mode = mode;
151 
152 	switch (mode) {
153 	case GPIO_MODE_INPUT:
154 		/* turn off output enable, act as input pin;
155 		 * program the pin as GPIO, mask out signal driven by HW */
156 		REG_UPDATE(EN_reg, EN, 0);
157 		REG_UPDATE(MASK_reg, MASK, 1);
158 		return GPIO_RESULT_OK;
159 	case GPIO_MODE_OUTPUT:
160 		/* turn on output enable, act as output pin;
161 		 * program the pin as GPIO, mask out signal driven by HW */
162 		REG_UPDATE(A_reg, A, 0);
163 		REG_UPDATE(MASK_reg, MASK, 1);
164 		return GPIO_RESULT_OK;
165 	case GPIO_MODE_FAST_OUTPUT:
166 		/* grounding the A register then use the EN register bit
167 		 * will have faster effect on the rise time */
168 		REG_UPDATE(A_reg, A, 0);
169 		REG_UPDATE(MASK_reg, MASK, 1);
170 		return GPIO_RESULT_OK;
171 	case GPIO_MODE_HARDWARE:
172 		/* program the pin as tri-state, pin is driven by HW */
173 		REG_UPDATE(MASK_reg, MASK, 0);
174 		return GPIO_RESULT_OK;
175 	case GPIO_MODE_INTERRUPT:
176 		/* Interrupt mode supported only by HPD (IrqGpio) pins. */
177 		REG_UPDATE(MASK_reg, MASK, 0);
178 		return GPIO_RESULT_OK;
179 	default:
180 		return GPIO_RESULT_NON_SPECIFIC_ERROR;
181 	}
182 }
183 
dal_hw_gpio_construct(struct hw_gpio * pin,enum gpio_id id,uint32_t en,struct dc_context * ctx)184 void dal_hw_gpio_construct(
185 	struct hw_gpio *pin,
186 	enum gpio_id id,
187 	uint32_t en,
188 	struct dc_context *ctx)
189 {
190 	pin->base.ctx = ctx;
191 	pin->base.id = id;
192 	pin->base.en = en;
193 	pin->base.mode = GPIO_MODE_UNKNOWN;
194 	pin->base.opened = false;
195 
196 	pin->store.mask = 0;
197 	pin->store.a = 0;
198 	pin->store.en = 0;
199 	pin->store.mux = 0;
200 
201 	pin->mux_supported = false;
202 }
203 
dal_hw_gpio_destruct(struct hw_gpio * pin)204 void dal_hw_gpio_destruct(
205 	struct hw_gpio *pin)
206 {
207 	ASSERT(!pin->base.opened);
208 }
209