1 /*
2  * Copyright (c) 2020-2022, Arm Limited. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <stdbool.h>
9 #include <stdint.h>
10 
11 #include "mhu_v2_x.h"
12 
13 #define MHU_V2_X_MAX_CHANNELS		124
14 #define MHU_V2_1_MAX_CHCOMB_INT		4
15 #define ENABLE				0x1
16 #define DISABLE				0x0
17 #define CLEAR_INTR			0x1
18 #define CH_PER_CH_COMB			0x20
19 #define SEND_FRAME(p_mhu)		((struct mhu_v2_x_send_frame_t *)p_mhu)
20 #define RECV_FRAME(p_mhu)		((struct mhu_v2_x_recv_frame_t *)p_mhu)
21 
22 #define MHU_MAJOR_REV_V2		0x1u
23 #define MHU_MINOR_REV_2_0		0x0u
24 #define MHU_MINOR_REV_2_1		0x1u
25 
26 struct mhu_v2_x_send_ch_window_t {
27 	/* Offset: 0x00 (R/ ) Channel Status */
28 	volatile uint32_t ch_st;
29 	/* Offset: 0x04 (R/ ) Reserved */
30 	volatile uint32_t reserved_0;
31 	/* Offset: 0x08 (R/ ) Reserved */
32 	volatile uint32_t reserved_1;
33 	/* Offset: 0x0C ( /W) Channel Set */
34 	volatile uint32_t ch_set;
35 	/* Offset: 0x10 (R/ ) Channel Interrupt Status (Reserved in 2.0) */
36 	volatile uint32_t ch_int_st;
37 	/* Offset: 0x14 ( /W) Channel Interrupt Clear  (Reserved in 2.0) */
38 	volatile uint32_t ch_int_clr;
39 	/* Offset: 0x18 (R/W) Channel Interrupt Enable (Reserved in 2.0) */
40 	volatile uint32_t ch_int_en;
41 	/* Offset: 0x1C (R/ ) Reserved */
42 	volatile uint32_t reserved_2;
43 };
44 
45 struct mhu_v2_x_send_frame_t {
46 	/* Offset: 0x000 ( / ) Sender Channel Window 0 -123 */
47 	struct mhu_v2_x_send_ch_window_t send_ch_window[MHU_V2_X_MAX_CHANNELS];
48 	/* Offset: 0xF80 (R/ ) Message Handling Unit Configuration */
49 	volatile uint32_t mhu_cfg;
50 	/* Offset: 0xF84 (R/W) Response Configuration */
51 	volatile uint32_t resp_cfg;
52 	/* Offset: 0xF88 (R/W) Access Request */
53 	volatile uint32_t access_request;
54 	/* Offset: 0xF8C (R/ ) Access Ready */
55 	volatile uint32_t access_ready;
56 	/* Offset: 0xF90 (R/ ) Interrupt Status */
57 	volatile uint32_t int_st;
58 	/* Offset: 0xF94 ( /W) Interrupt Clear */
59 	volatile uint32_t int_clr;
60 	/* Offset: 0xF98 (R/W) Interrupt Enable */
61 	volatile uint32_t int_en;
62 	/* Offset: 0xF9C (R/ ) Reserved */
63 	volatile uint32_t reserved_0;
64 	/* Offset: 0xFA0 (R/W) Channel Combined IRQ Stat (Reserved in 2.0) */
65 	volatile uint32_t ch_comb_int_st[MHU_V2_1_MAX_CHCOMB_INT];
66 	/* Offset: 0xFC4 (R/ ) Reserved */
67 	volatile uint32_t reserved_1[6];
68 	/* Offset: 0xFC8 (R/ ) Implementer Identification Register */
69 	volatile uint32_t iidr;
70 	/* Offset: 0xFCC (R/ ) Architecture Identification Register */
71 	volatile uint32_t aidr;
72 	/* Offset: 0xFD0 (R/ )  */
73 	volatile uint32_t pid_1[4];
74 	/* Offset: 0xFE0 (R/ )  */
75 	volatile uint32_t pid_0[4];
76 	/* Offset: 0xFF0 (R/ )  */
77 	volatile uint32_t cid[4];
78 };
79 
80 struct mhu_v2_x_rec_ch_window_t {
81 	/* Offset: 0x00 (R/ ) Channel Status */
82 	volatile uint32_t ch_st;
83 	/* Offset: 0x04 (R/ ) Channel Status Masked */
84 	volatile uint32_t ch_st_msk;
85 	/* Offset: 0x08 ( /W) Channel Clear */
86 	volatile uint32_t ch_clr;
87 	/* Offset: 0x0C (R/ ) Reserved */
88 	volatile uint32_t reserved_0;
89 	/* Offset: 0x10 (R/ ) Channel Mask Status */
90 	volatile uint32_t ch_msk_st;
91 	/* Offset: 0x14 ( /W) Channel Mask Set */
92 	volatile uint32_t ch_msk_set;
93 	/* Offset: 0x18 ( /W) Channel Mask Clear */
94 	volatile uint32_t ch_msk_clr;
95 	/* Offset: 0x1C (R/ ) Reserved */
96 	volatile uint32_t reserved_1;
97 };
98 
99 struct mhu_v2_x_recv_frame_t {
100 	/* Offset: 0x000 ( / ) Receiver Channel Window 0 -123 */
101 	struct mhu_v2_x_rec_ch_window_t rec_ch_window[MHU_V2_X_MAX_CHANNELS];
102 	/* Offset: 0xF80 (R/ ) Message Handling Unit Configuration */
103 	volatile uint32_t mhu_cfg;
104 	/* Offset: 0xF84 (R/ ) Reserved */
105 	volatile uint32_t reserved_0[3];
106 	/* Offset: 0xF90 (R/ ) Interrupt Status (Reserved in 2.0) */
107 	volatile uint32_t int_st;
108 	/* Offset: 0xF94 (R/ ) Interrupt Clear  (Reserved in 2.0) */
109 	volatile uint32_t int_clr;
110 	/* Offset: 0xF98 (R/W) Interrupt Enable (Reserved in 2.0) */
111 	volatile uint32_t int_en;
112 	/* Offset: 0xF9C (R/ ) Reserved  */
113 	volatile uint32_t reserved_1;
114 	/* Offset: 0xFA0 (R/ ) Channel Combined IRQ Stat (Reserved in 2.0) */
115 	volatile uint32_t ch_comb_int_st[MHU_V2_1_MAX_CHCOMB_INT];
116 	/* Offset: 0xFB0 (R/ ) Reserved */
117 	volatile uint32_t reserved_2[6];
118 	/* Offset: 0xFC8 (R/ ) Implementer Identification Register */
119 	volatile uint32_t iidr;
120 	/* Offset: 0xFCC (R/ ) Architecture Identification Register */
121 	volatile uint32_t aidr;
122 	/* Offset: 0xFD0 (R/ )  */
123 	volatile uint32_t pid_1[4];
124 	/* Offset: 0xFE0 (R/ )  */
125 	volatile uint32_t pid_0[4];
126 	/* Offset: 0xFF0 (R/ )  */
127 	volatile uint32_t cid[4];
128 };
129 
130 union mhu_v2_x_frame {
131 	struct mhu_v2_x_send_frame_t send_frame;
132 	struct mhu_v2_x_recv_frame_t recv_frame;
133 };
134 
mhu_v2_x_driver_init(struct mhu_v2_x_dev_t * dev,enum mhu_v2_x_supported_revisions rev)135 enum mhu_v2_x_error_t mhu_v2_x_driver_init(struct mhu_v2_x_dev_t *dev,
136 	 enum mhu_v2_x_supported_revisions rev)
137 {
138 	uint32_t AIDR = 0;
139 	union mhu_v2_x_frame *p_mhu;
140 
141 	assert(dev != NULL);
142 
143 	p_mhu = (union mhu_v2_x_frame *)dev->base;
144 
145 	if (dev->is_initialized) {
146 		return MHU_V_2_X_ERR_ALREADY_INIT;
147 	}
148 
149 	if (rev == MHU_REV_READ_FROM_HW) {
150 		/* Read revision from HW */
151 		if (dev->frame == MHU_V2_X_RECEIVER_FRAME) {
152 			AIDR = p_mhu->recv_frame.aidr;
153 		} else {
154 			AIDR = p_mhu->send_frame.aidr;
155 		}
156 
157 		/* Get bits 7:4 to read major revision */
158 		if (((AIDR >> 4) & 0b1111) != MHU_MAJOR_REV_V2) {
159 			/* Unsupported MHU version */
160 			return MHU_V_2_X_ERR_UNSUPPORTED_VERSION;
161 		} /* No need to save major version, driver only supports MHUv2 */
162 
163 		/* Get bits 3:0 to read minor revision */
164 		dev->subversion = AIDR & 0b1111;
165 
166 		if (dev->subversion != MHU_MINOR_REV_2_0 &&
167 			dev->subversion != MHU_MINOR_REV_2_1) {
168 			/* Unsupported subversion */
169 			return MHU_V_2_X_ERR_UNSUPPORTED_VERSION;
170 		}
171 	} else {
172 		/* Revisions were provided by caller */
173 		if (rev == MHU_REV_2_0) {
174 			dev->subversion = MHU_MINOR_REV_2_0;
175 		} else if (rev == MHU_REV_2_1) {
176 			dev->subversion = MHU_MINOR_REV_2_1;
177 		} else {
178 			/* Unsupported subversion */
179 			return MHU_V_2_X_ERR_UNSUPPORTED_VERSION;
180 		} /* No need to save major version, driver only supports MHUv2 */
181 	}
182 
183 	dev->is_initialized = true;
184 
185 	return MHU_V_2_X_ERR_NONE;
186 }
187 
mhu_v2_x_get_num_channel_implemented(const struct mhu_v2_x_dev_t * dev)188 uint32_t mhu_v2_x_get_num_channel_implemented(const struct mhu_v2_x_dev_t *dev)
189 {
190 	union mhu_v2_x_frame *p_mhu;
191 
192 	assert(dev != NULL);
193 
194 	p_mhu = (union mhu_v2_x_frame *)dev->base;
195 
196 	if (!(dev->is_initialized)) {
197 		return MHU_V_2_X_ERR_NOT_INIT;
198 	}
199 
200 	if (dev->frame == MHU_V2_X_SENDER_FRAME) {
201 		return (SEND_FRAME(p_mhu))->mhu_cfg;
202 	} else {
203 		assert(dev->frame == MHU_V2_X_RECEIVER_FRAME);
204 		return (RECV_FRAME(p_mhu))->mhu_cfg;
205 	}
206 }
207 
mhu_v2_x_channel_send(const struct mhu_v2_x_dev_t * dev,uint32_t channel,uint32_t val)208 enum mhu_v2_x_error_t mhu_v2_x_channel_send(const struct mhu_v2_x_dev_t *dev,
209 	 uint32_t channel, uint32_t val)
210 {
211 	union mhu_v2_x_frame *p_mhu;
212 
213 	assert(dev != NULL);
214 
215 	p_mhu = (union mhu_v2_x_frame *)dev->base;
216 
217 	if (!(dev->is_initialized)) {
218 		return MHU_V_2_X_ERR_NOT_INIT;
219 	}
220 
221 	if (dev->frame == MHU_V2_X_SENDER_FRAME) {
222 		(SEND_FRAME(p_mhu))->send_ch_window[channel].ch_set = val;
223 		return MHU_V_2_X_ERR_NONE;
224 	} else {
225 		return MHU_V_2_X_ERR_INVALID_ARG;
226 	}
227 }
228 
mhu_v2_x_channel_poll(const struct mhu_v2_x_dev_t * dev,uint32_t channel,uint32_t * value)229 enum mhu_v2_x_error_t mhu_v2_x_channel_poll(const struct mhu_v2_x_dev_t *dev,
230 	 uint32_t channel, uint32_t *value)
231 {
232 	union mhu_v2_x_frame *p_mhu;
233 
234 	assert(dev != NULL);
235 
236 	p_mhu = (union mhu_v2_x_frame *)dev->base;
237 
238 	if (!(dev->is_initialized)) {
239 		return MHU_V_2_X_ERR_NOT_INIT;
240 	}
241 
242 	if (dev->frame == MHU_V2_X_SENDER_FRAME) {
243 		*value = (SEND_FRAME(p_mhu))->send_ch_window[channel].ch_st;
244 		return MHU_V_2_X_ERR_NONE;
245 	} else {
246 		return MHU_V_2_X_ERR_INVALID_ARG;
247 	}
248 }
249 
mhu_v2_x_channel_clear(const struct mhu_v2_x_dev_t * dev,uint32_t channel)250 enum mhu_v2_x_error_t mhu_v2_x_channel_clear(const struct mhu_v2_x_dev_t *dev,
251 	 uint32_t channel)
252 {
253 	union mhu_v2_x_frame *p_mhu;
254 
255 	assert(dev != NULL);
256 
257 	p_mhu = (union mhu_v2_x_frame *)dev->base;
258 
259 	if (!(dev->is_initialized)) {
260 		return MHU_V_2_X_ERR_NOT_INIT;
261 	}
262 
263 	if (dev->frame == MHU_V2_X_RECEIVER_FRAME) {
264 		(RECV_FRAME(p_mhu))->rec_ch_window[channel].ch_clr = UINT32_MAX;
265 		return MHU_V_2_X_ERR_NONE;
266 	} else {
267 		return MHU_V_2_X_ERR_INVALID_ARG;
268 	}
269 }
270 
mhu_v2_x_channel_receive(const struct mhu_v2_x_dev_t * dev,uint32_t channel,uint32_t * value)271 enum mhu_v2_x_error_t mhu_v2_x_channel_receive(
272 	 const struct mhu_v2_x_dev_t *dev, uint32_t channel, uint32_t *value)
273 {
274 	union mhu_v2_x_frame *p_mhu;
275 
276 	assert(dev != NULL);
277 
278 	p_mhu = (union mhu_v2_x_frame *)dev->base;
279 
280 	if (!(dev->is_initialized)) {
281 		return MHU_V_2_X_ERR_NOT_INIT;
282 	}
283 
284 	if (dev->frame == MHU_V2_X_RECEIVER_FRAME) {
285 		*value = (RECV_FRAME(p_mhu))->rec_ch_window[channel].ch_st;
286 		return MHU_V_2_X_ERR_NONE;
287 	} else {
288 		return MHU_V_2_X_ERR_INVALID_ARG;
289 	}
290 }
291 
mhu_v2_x_channel_mask_set(const struct mhu_v2_x_dev_t * dev,uint32_t channel,uint32_t mask)292 enum mhu_v2_x_error_t mhu_v2_x_channel_mask_set(
293 	 const struct mhu_v2_x_dev_t *dev, uint32_t channel, uint32_t mask)
294 {
295 	union mhu_v2_x_frame *p_mhu;
296 
297 	assert(dev != NULL);
298 
299 	p_mhu = (union mhu_v2_x_frame *)dev->base;
300 
301 	if (!(dev->is_initialized)) {
302 		return MHU_V_2_X_ERR_NOT_INIT;
303 	}
304 
305 	if (dev->frame == MHU_V2_X_RECEIVER_FRAME) {
306 		(RECV_FRAME(p_mhu))->rec_ch_window[channel].ch_msk_set = mask;
307 		return MHU_V_2_X_ERR_NONE;
308 	} else {
309 		return MHU_V_2_X_ERR_INVALID_ARG;
310 	}
311 }
312 
mhu_v2_x_channel_mask_clear(const struct mhu_v2_x_dev_t * dev,uint32_t channel,uint32_t mask)313 enum mhu_v2_x_error_t mhu_v2_x_channel_mask_clear(
314 	 const struct mhu_v2_x_dev_t *dev, uint32_t channel, uint32_t mask)
315 {
316 	union mhu_v2_x_frame *p_mhu;
317 
318 	assert(dev != NULL);
319 
320 	p_mhu = (union mhu_v2_x_frame *)dev->base;
321 
322 	if (!(dev->is_initialized)) {
323 		return MHU_V_2_X_ERR_NOT_INIT;
324 	}
325 
326 	if (dev->frame == MHU_V2_X_RECEIVER_FRAME) {
327 		(RECV_FRAME(p_mhu))->rec_ch_window[channel].ch_msk_clr = mask;
328 		return MHU_V_2_X_ERR_NONE;
329 	} else {
330 		return MHU_V_2_X_ERR_INVALID_ARG;
331 	}
332 }
mhu_v2_x_initiate_transfer(const struct mhu_v2_x_dev_t * dev)333 enum mhu_v2_x_error_t mhu_v2_x_initiate_transfer(
334 	 const struct mhu_v2_x_dev_t *dev)
335 {
336 	union mhu_v2_x_frame *p_mhu;
337 
338 	assert(dev != NULL);
339 
340 	p_mhu = (union mhu_v2_x_frame *)dev->base;
341 
342 	if (!(dev->is_initialized)) {
343 		return MHU_V_2_X_ERR_NOT_INIT;
344 	}
345 
346 	if (dev->frame != MHU_V2_X_SENDER_FRAME) {
347 		return MHU_V_2_X_ERR_INVALID_ARG;
348 	}
349 
350 	(SEND_FRAME(p_mhu))->access_request = ENABLE;
351 
352 	while (!((SEND_FRAME(p_mhu))->access_ready)) {
353 		/* Wait in a loop for access ready signal to be high */
354 		;
355 	}
356 
357 	return MHU_V_2_X_ERR_NONE;
358 }
359 
mhu_v2_x_close_transfer(const struct mhu_v2_x_dev_t * dev)360 enum mhu_v2_x_error_t mhu_v2_x_close_transfer(const struct mhu_v2_x_dev_t *dev)
361 {
362 	union mhu_v2_x_frame *p_mhu;
363 
364 	assert(dev != NULL);
365 
366 	p_mhu = (union mhu_v2_x_frame *)dev->base;
367 
368 	if (!(dev->is_initialized)) {
369 		return MHU_V_2_X_ERR_NOT_INIT;
370 	}
371 
372 	if (dev->frame != MHU_V2_X_SENDER_FRAME) {
373 		return MHU_V_2_X_ERR_INVALID_ARG;
374 	}
375 
376 	(SEND_FRAME(p_mhu))->access_request = DISABLE;
377 
378 	return MHU_V_2_X_ERR_NONE;
379 }
380