1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright 1998-2008 VIA Technologies, Inc. All Rights Reserved.
4 * Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.
5 * Copyright 2011 Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
6 */
7/*
8 * clock and PLL management functions
9 */
10
11#include <linux/kernel.h>
12#include <linux/via-core.h>
13
14#include "via_clock.h"
15#include "global.h"
16#include "debug.h"
17
18static const char *via_slap = "Please slap VIA Technologies to motivate them "
19	"releasing full documentation for your platform!\n";
20
21static inline u32 cle266_encode_pll(struct via_pll_config pll)
22{
23	return (pll.multiplier << 8)
24		| (pll.rshift << 6)
25		| pll.divisor;
26}
27
28static inline u32 k800_encode_pll(struct via_pll_config pll)
29{
30	return ((pll.divisor - 2) << 16)
31		| (pll.rshift << 10)
32		| (pll.multiplier - 2);
33}
34
35static inline u32 vx855_encode_pll(struct via_pll_config pll)
36{
37	return (pll.divisor << 16)
38		| (pll.rshift << 10)
39		| pll.multiplier;
40}
41
42static inline void cle266_set_primary_pll_encoded(u32 data)
43{
44	via_write_reg_mask(VIASR, 0x40, 0x02, 0x02); /* enable reset */
45	via_write_reg(VIASR, 0x46, data & 0xFF);
46	via_write_reg(VIASR, 0x47, (data >> 8) & 0xFF);
47	via_write_reg_mask(VIASR, 0x40, 0x00, 0x02); /* disable reset */
48}
49
50static inline void k800_set_primary_pll_encoded(u32 data)
51{
52	via_write_reg_mask(VIASR, 0x40, 0x02, 0x02); /* enable reset */
53	via_write_reg(VIASR, 0x44, data & 0xFF);
54	via_write_reg(VIASR, 0x45, (data >> 8) & 0xFF);
55	via_write_reg(VIASR, 0x46, (data >> 16) & 0xFF);
56	via_write_reg_mask(VIASR, 0x40, 0x00, 0x02); /* disable reset */
57}
58
59static inline void cle266_set_secondary_pll_encoded(u32 data)
60{
61	via_write_reg_mask(VIASR, 0x40, 0x04, 0x04); /* enable reset */
62	via_write_reg(VIASR, 0x44, data & 0xFF);
63	via_write_reg(VIASR, 0x45, (data >> 8) & 0xFF);
64	via_write_reg_mask(VIASR, 0x40, 0x00, 0x04); /* disable reset */
65}
66
67static inline void k800_set_secondary_pll_encoded(u32 data)
68{
69	via_write_reg_mask(VIASR, 0x40, 0x04, 0x04); /* enable reset */
70	via_write_reg(VIASR, 0x4A, data & 0xFF);
71	via_write_reg(VIASR, 0x4B, (data >> 8) & 0xFF);
72	via_write_reg(VIASR, 0x4C, (data >> 16) & 0xFF);
73	via_write_reg_mask(VIASR, 0x40, 0x00, 0x04); /* disable reset */
74}
75
76static inline void set_engine_pll_encoded(u32 data)
77{
78	via_write_reg_mask(VIASR, 0x40, 0x01, 0x01); /* enable reset */
79	via_write_reg(VIASR, 0x47, data & 0xFF);
80	via_write_reg(VIASR, 0x48, (data >> 8) & 0xFF);
81	via_write_reg(VIASR, 0x49, (data >> 16) & 0xFF);
82	via_write_reg_mask(VIASR, 0x40, 0x00, 0x01); /* disable reset */
83}
84
85static void cle266_set_primary_pll(struct via_pll_config config)
86{
87	cle266_set_primary_pll_encoded(cle266_encode_pll(config));
88}
89
90static void k800_set_primary_pll(struct via_pll_config config)
91{
92	k800_set_primary_pll_encoded(k800_encode_pll(config));
93}
94
95static void vx855_set_primary_pll(struct via_pll_config config)
96{
97	k800_set_primary_pll_encoded(vx855_encode_pll(config));
98}
99
100static void cle266_set_secondary_pll(struct via_pll_config config)
101{
102	cle266_set_secondary_pll_encoded(cle266_encode_pll(config));
103}
104
105static void k800_set_secondary_pll(struct via_pll_config config)
106{
107	k800_set_secondary_pll_encoded(k800_encode_pll(config));
108}
109
110static void vx855_set_secondary_pll(struct via_pll_config config)
111{
112	k800_set_secondary_pll_encoded(vx855_encode_pll(config));
113}
114
115static void k800_set_engine_pll(struct via_pll_config config)
116{
117	set_engine_pll_encoded(k800_encode_pll(config));
118}
119
120static void vx855_set_engine_pll(struct via_pll_config config)
121{
122	set_engine_pll_encoded(vx855_encode_pll(config));
123}
124
125static void set_primary_pll_state(u8 state)
126{
127	u8 value;
128
129	switch (state) {
130	case VIA_STATE_ON:
131		value = 0x20;
132		break;
133	case VIA_STATE_OFF:
134		value = 0x00;
135		break;
136	default:
137		return;
138	}
139
140	via_write_reg_mask(VIASR, 0x2D, value, 0x30);
141}
142
143static void set_secondary_pll_state(u8 state)
144{
145	u8 value;
146
147	switch (state) {
148	case VIA_STATE_ON:
149		value = 0x08;
150		break;
151	case VIA_STATE_OFF:
152		value = 0x00;
153		break;
154	default:
155		return;
156	}
157
158	via_write_reg_mask(VIASR, 0x2D, value, 0x0C);
159}
160
161static void set_engine_pll_state(u8 state)
162{
163	u8 value;
164
165	switch (state) {
166	case VIA_STATE_ON:
167		value = 0x02;
168		break;
169	case VIA_STATE_OFF:
170		value = 0x00;
171		break;
172	default:
173		return;
174	}
175
176	via_write_reg_mask(VIASR, 0x2D, value, 0x03);
177}
178
179static void set_primary_clock_state(u8 state)
180{
181	u8 value;
182
183	switch (state) {
184	case VIA_STATE_ON:
185		value = 0x20;
186		break;
187	case VIA_STATE_OFF:
188		value = 0x00;
189		break;
190	default:
191		return;
192	}
193
194	via_write_reg_mask(VIASR, 0x1B, value, 0x30);
195}
196
197static void set_secondary_clock_state(u8 state)
198{
199	u8 value;
200
201	switch (state) {
202	case VIA_STATE_ON:
203		value = 0x80;
204		break;
205	case VIA_STATE_OFF:
206		value = 0x00;
207		break;
208	default:
209		return;
210	}
211
212	via_write_reg_mask(VIASR, 0x1B, value, 0xC0);
213}
214
215static inline u8 set_clock_source_common(enum via_clksrc source, bool use_pll)
216{
217	u8 data = 0;
218
219	switch (source) {
220	case VIA_CLKSRC_X1:
221		data = 0x00;
222		break;
223	case VIA_CLKSRC_TVX1:
224		data = 0x02;
225		break;
226	case VIA_CLKSRC_TVPLL:
227		data = 0x04; /* 0x06 should be the same */
228		break;
229	case VIA_CLKSRC_DVP1TVCLKR:
230		data = 0x0A;
231		break;
232	case VIA_CLKSRC_CAP0:
233		data = 0xC;
234		break;
235	case VIA_CLKSRC_CAP1:
236		data = 0x0E;
237		break;
238	}
239
240	if (!use_pll)
241		data |= 1;
242
243	return data;
244}
245
246static void set_primary_clock_source(enum via_clksrc source, bool use_pll)
247{
248	u8 data = set_clock_source_common(source, use_pll) << 4;
249	via_write_reg_mask(VIACR, 0x6C, data, 0xF0);
250}
251
252static void set_secondary_clock_source(enum via_clksrc source, bool use_pll)
253{
254	u8 data = set_clock_source_common(source, use_pll);
255	via_write_reg_mask(VIACR, 0x6C, data, 0x0F);
256}
257
258static void dummy_set_clock_state(u8 state)
259{
260	printk(KERN_INFO "Using undocumented set clock state.\n%s", via_slap);
261}
262
263static void dummy_set_clock_source(enum via_clksrc source, bool use_pll)
264{
265	printk(KERN_INFO "Using undocumented set clock source.\n%s", via_slap);
266}
267
268static void dummy_set_pll_state(u8 state)
269{
270	printk(KERN_INFO "Using undocumented set PLL state.\n%s", via_slap);
271}
272
273static void dummy_set_pll(struct via_pll_config config)
274{
275	printk(KERN_INFO "Using undocumented set PLL.\n%s", via_slap);
276}
277
278static void noop_set_clock_state(u8 state)
279{
280}
281
282void via_clock_init(struct via_clock *clock, int gfx_chip)
283{
284	switch (gfx_chip) {
285	case UNICHROME_CLE266:
286	case UNICHROME_K400:
287		clock->set_primary_clock_state = dummy_set_clock_state;
288		clock->set_primary_clock_source = dummy_set_clock_source;
289		clock->set_primary_pll_state = dummy_set_pll_state;
290		clock->set_primary_pll = cle266_set_primary_pll;
291
292		clock->set_secondary_clock_state = dummy_set_clock_state;
293		clock->set_secondary_clock_source = dummy_set_clock_source;
294		clock->set_secondary_pll_state = dummy_set_pll_state;
295		clock->set_secondary_pll = cle266_set_secondary_pll;
296
297		clock->set_engine_pll_state = dummy_set_pll_state;
298		clock->set_engine_pll = dummy_set_pll;
299		break;
300	case UNICHROME_K800:
301	case UNICHROME_PM800:
302	case UNICHROME_CN700:
303	case UNICHROME_CX700:
304	case UNICHROME_CN750:
305	case UNICHROME_K8M890:
306	case UNICHROME_P4M890:
307	case UNICHROME_P4M900:
308	case UNICHROME_VX800:
309		clock->set_primary_clock_state = set_primary_clock_state;
310		clock->set_primary_clock_source = set_primary_clock_source;
311		clock->set_primary_pll_state = set_primary_pll_state;
312		clock->set_primary_pll = k800_set_primary_pll;
313
314		clock->set_secondary_clock_state = set_secondary_clock_state;
315		clock->set_secondary_clock_source = set_secondary_clock_source;
316		clock->set_secondary_pll_state = set_secondary_pll_state;
317		clock->set_secondary_pll = k800_set_secondary_pll;
318
319		clock->set_engine_pll_state = set_engine_pll_state;
320		clock->set_engine_pll = k800_set_engine_pll;
321		break;
322	case UNICHROME_VX855:
323	case UNICHROME_VX900:
324		clock->set_primary_clock_state = set_primary_clock_state;
325		clock->set_primary_clock_source = set_primary_clock_source;
326		clock->set_primary_pll_state = set_primary_pll_state;
327		clock->set_primary_pll = vx855_set_primary_pll;
328
329		clock->set_secondary_clock_state = set_secondary_clock_state;
330		clock->set_secondary_clock_source = set_secondary_clock_source;
331		clock->set_secondary_pll_state = set_secondary_pll_state;
332		clock->set_secondary_pll = vx855_set_secondary_pll;
333
334		clock->set_engine_pll_state = set_engine_pll_state;
335		clock->set_engine_pll = vx855_set_engine_pll;
336		break;
337
338	}
339
340	if (machine_is_olpc()) {
341		/* The OLPC XO-1.5 cannot suspend/resume reliably if the
342		 * IGA1/IGA2 clocks are set as on or off (memory rot
343		 * occasionally happens during suspend under such
344		 * configurations).
345		 *
346		 * The only known stable scenario is to leave this bits as-is,
347		 * which in their default states are documented to enable the
348		 * clock only when it is needed.
349		 */
350		clock->set_primary_clock_state = noop_set_clock_state;
351		clock->set_secondary_clock_state = noop_set_clock_state;
352	}
353}
354