1 /*
2  * Copyright 2012 Red Hat Inc.
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: Ben Skeggs
23  */
24 #define mcp77_clk(p) container_of((p), struct mcp77_clk, base)
25 #include "gt215.h"
26 #include "pll.h"
27 
28 #include <subdev/bios.h>
29 #include <subdev/bios/pll.h>
30 #include <subdev/timer.h>
31 
32 struct mcp77_clk {
33 	struct nvkm_clk base;
34 	enum nv_clk_src csrc, ssrc, vsrc;
35 	u32 cctrl, sctrl;
36 	u32 ccoef, scoef;
37 	u32 cpost, spost;
38 	u32 vdiv;
39 };
40 
41 static u32
42 read_div(struct mcp77_clk *clk)
43 {
44 	struct nvkm_device *device = clk->base.subdev.device;
45 	return nvkm_rd32(device, 0x004600);
46 }
47 
48 static u32
49 read_pll(struct mcp77_clk *clk, u32 base)
50 {
51 	struct nvkm_device *device = clk->base.subdev.device;
52 	u32 ctrl = nvkm_rd32(device, base + 0);
53 	u32 coef = nvkm_rd32(device, base + 4);
54 	u32 ref = nvkm_clk_read(&clk->base, nv_clk_src_href);
55 	u32 post_div = 0;
56 	u32 clock = 0;
57 	int N1, M1;
58 
59 	switch (base){
60 	case 0x4020:
61 		post_div = 1 << ((nvkm_rd32(device, 0x4070) & 0x000f0000) >> 16);
62 		break;
63 	case 0x4028:
64 		post_div = (nvkm_rd32(device, 0x4040) & 0x000f0000) >> 16;
65 		break;
66 	default:
67 		break;
68 	}
69 
70 	N1 = (coef & 0x0000ff00) >> 8;
71 	M1 = (coef & 0x000000ff);
72 	if ((ctrl & 0x80000000) && M1) {
73 		clock = ref * N1 / M1;
74 		clock = clock / post_div;
75 	}
76 
77 	return clock;
78 }
79 
80 static int
81 mcp77_clk_read(struct nvkm_clk *base, enum nv_clk_src src)
82 {
83 	struct mcp77_clk *clk = mcp77_clk(base);
84 	struct nvkm_subdev *subdev = &clk->base.subdev;
85 	struct nvkm_device *device = subdev->device;
86 	u32 mast = nvkm_rd32(device, 0x00c054);
87 	u32 P = 0;
88 
89 	switch (src) {
90 	case nv_clk_src_crystal:
91 		return device->crystal;
92 	case nv_clk_src_href:
93 		return 100000; /* PCIE reference clock */
94 	case nv_clk_src_hclkm4:
95 		return nvkm_clk_read(&clk->base, nv_clk_src_href) * 4;
96 	case nv_clk_src_hclkm2d3:
97 		return nvkm_clk_read(&clk->base, nv_clk_src_href) * 2 / 3;
98 	case nv_clk_src_host:
99 		switch (mast & 0x000c0000) {
100 		case 0x00000000: return nvkm_clk_read(&clk->base, nv_clk_src_hclkm2d3);
101 		case 0x00040000: break;
102 		case 0x00080000: return nvkm_clk_read(&clk->base, nv_clk_src_hclkm4);
103 		case 0x000c0000: return nvkm_clk_read(&clk->base, nv_clk_src_cclk);
104 		}
105 		break;
106 	case nv_clk_src_core:
107 		P = (nvkm_rd32(device, 0x004028) & 0x00070000) >> 16;
108 
109 		switch (mast & 0x00000003) {
110 		case 0x00000000: return nvkm_clk_read(&clk->base, nv_clk_src_crystal) >> P;
111 		case 0x00000001: return 0;
112 		case 0x00000002: return nvkm_clk_read(&clk->base, nv_clk_src_hclkm4) >> P;
113 		case 0x00000003: return read_pll(clk, 0x004028) >> P;
114 		}
115 		break;
116 	case nv_clk_src_cclk:
117 		if ((mast & 0x03000000) != 0x03000000)
118 			return nvkm_clk_read(&clk->base, nv_clk_src_core);
119 
120 		if ((mast & 0x00000200) == 0x00000000)
121 			return nvkm_clk_read(&clk->base, nv_clk_src_core);
122 
123 		switch (mast & 0x00000c00) {
124 		case 0x00000000: return nvkm_clk_read(&clk->base, nv_clk_src_href);
125 		case 0x00000400: return nvkm_clk_read(&clk->base, nv_clk_src_hclkm4);
126 		case 0x00000800: return nvkm_clk_read(&clk->base, nv_clk_src_hclkm2d3);
127 		default: return 0;
128 		}
129 	case nv_clk_src_shader:
130 		P = (nvkm_rd32(device, 0x004020) & 0x00070000) >> 16;
131 		switch (mast & 0x00000030) {
132 		case 0x00000000:
133 			if (mast & 0x00000040)
134 				return nvkm_clk_read(&clk->base, nv_clk_src_href) >> P;
135 			return nvkm_clk_read(&clk->base, nv_clk_src_crystal) >> P;
136 		case 0x00000010: break;
137 		case 0x00000020: return read_pll(clk, 0x004028) >> P;
138 		case 0x00000030: return read_pll(clk, 0x004020) >> P;
139 		}
140 		break;
141 	case nv_clk_src_mem:
142 		return 0;
143 		break;
144 	case nv_clk_src_vdec:
145 		P = (read_div(clk) & 0x00000700) >> 8;
146 
147 		switch (mast & 0x00400000) {
148 		case 0x00400000:
149 			return nvkm_clk_read(&clk->base, nv_clk_src_core) >> P;
150 			break;
151 		default:
152 			return 500000 >> P;
153 			break;
154 		}
155 		break;
156 	default:
157 		break;
158 	}
159 
160 	nvkm_debug(subdev, "unknown clock source %d %08x\n", src, mast);
161 	return 0;
162 }
163 
164 static u32
165 calc_pll(struct mcp77_clk *clk, u32 reg,
166 	 u32 clock, int *N, int *M, int *P)
167 {
168 	struct nvkm_subdev *subdev = &clk->base.subdev;
169 	struct nvbios_pll pll;
170 	int ret;
171 
172 	ret = nvbios_pll_parse(subdev->device->bios, reg, &pll);
173 	if (ret)
174 		return 0;
175 
176 	pll.vco2.max_freq = 0;
177 	pll.refclk = nvkm_clk_read(&clk->base, nv_clk_src_href);
178 	if (!pll.refclk)
179 		return 0;
180 
181 	return nv04_pll_calc(subdev, &pll, clock, N, M, NULL, NULL, P);
182 }
183 
184 static inline u32
185 calc_P(u32 src, u32 target, int *div)
186 {
187 	u32 clk0 = src, clk1 = src;
188 	for (*div = 0; *div <= 7; (*div)++) {
189 		if (clk0 <= target) {
190 			clk1 = clk0 << (*div ? 1 : 0);
191 			break;
192 		}
193 		clk0 >>= 1;
194 	}
195 
196 	if (target - clk0 <= clk1 - target)
197 		return clk0;
198 	(*div)--;
199 	return clk1;
200 }
201 
202 static int
203 mcp77_clk_calc(struct nvkm_clk *base, struct nvkm_cstate *cstate)
204 {
205 	struct mcp77_clk *clk = mcp77_clk(base);
206 	const int shader = cstate->domain[nv_clk_src_shader];
207 	const int core = cstate->domain[nv_clk_src_core];
208 	const int vdec = cstate->domain[nv_clk_src_vdec];
209 	struct nvkm_subdev *subdev = &clk->base.subdev;
210 	u32 out = 0, clock = 0;
211 	int N, M, P1, P2 = 0;
212 	int divs = 0;
213 
214 	/* cclk: find suitable source, disable PLL if we can */
215 	if (core < nvkm_clk_read(&clk->base, nv_clk_src_hclkm4))
216 		out = calc_P(nvkm_clk_read(&clk->base, nv_clk_src_hclkm4), core, &divs);
217 
218 	/* Calculate clock * 2, so shader clock can use it too */
219 	clock = calc_pll(clk, 0x4028, (core << 1), &N, &M, &P1);
220 
221 	if (abs(core - out) <= abs(core - (clock >> 1))) {
222 		clk->csrc = nv_clk_src_hclkm4;
223 		clk->cctrl = divs << 16;
224 	} else {
225 		/* NVCTRL is actually used _after_ NVPOST, and after what we
226 		 * call NVPLL. To make matters worse, NVPOST is an integer
227 		 * divider instead of a right-shift number. */
228 		if(P1 > 2) {
229 			P2 = P1 - 2;
230 			P1 = 2;
231 		}
232 
233 		clk->csrc = nv_clk_src_core;
234 		clk->ccoef = (N << 8) | M;
235 
236 		clk->cctrl = (P2 + 1) << 16;
237 		clk->cpost = (1 << P1) << 16;
238 	}
239 
240 	/* sclk: nvpll + divisor, href or spll */
241 	out = 0;
242 	if (shader == nvkm_clk_read(&clk->base, nv_clk_src_href)) {
243 		clk->ssrc = nv_clk_src_href;
244 	} else {
245 		clock = calc_pll(clk, 0x4020, shader, &N, &M, &P1);
246 		if (clk->csrc == nv_clk_src_core)
247 			out = calc_P((core << 1), shader, &divs);
248 
249 		if (abs(shader - out) <=
250 		    abs(shader - clock) &&
251 		   (divs + P2) <= 7) {
252 			clk->ssrc = nv_clk_src_core;
253 			clk->sctrl = (divs + P2) << 16;
254 		} else {
255 			clk->ssrc = nv_clk_src_shader;
256 			clk->scoef = (N << 8) | M;
257 			clk->sctrl = P1 << 16;
258 		}
259 	}
260 
261 	/* vclk */
262 	out = calc_P(core, vdec, &divs);
263 	clock = calc_P(500000, vdec, &P1);
264 	if(abs(vdec - out) <= abs(vdec - clock)) {
265 		clk->vsrc = nv_clk_src_cclk;
266 		clk->vdiv = divs << 16;
267 	} else {
268 		clk->vsrc = nv_clk_src_vdec;
269 		clk->vdiv = P1 << 16;
270 	}
271 
272 	/* Print strategy! */
273 	nvkm_debug(subdev, "nvpll: %08x %08x %08x\n",
274 		   clk->ccoef, clk->cpost, clk->cctrl);
275 	nvkm_debug(subdev, " spll: %08x %08x %08x\n",
276 		   clk->scoef, clk->spost, clk->sctrl);
277 	nvkm_debug(subdev, " vdiv: %08x\n", clk->vdiv);
278 	if (clk->csrc == nv_clk_src_hclkm4)
279 		nvkm_debug(subdev, "core: hrefm4\n");
280 	else
281 		nvkm_debug(subdev, "core: nvpll\n");
282 
283 	if (clk->ssrc == nv_clk_src_hclkm4)
284 		nvkm_debug(subdev, "shader: hrefm4\n");
285 	else if (clk->ssrc == nv_clk_src_core)
286 		nvkm_debug(subdev, "shader: nvpll\n");
287 	else
288 		nvkm_debug(subdev, "shader: spll\n");
289 
290 	if (clk->vsrc == nv_clk_src_hclkm4)
291 		nvkm_debug(subdev, "vdec: 500MHz\n");
292 	else
293 		nvkm_debug(subdev, "vdec: core\n");
294 
295 	return 0;
296 }
297 
298 static int
299 mcp77_clk_prog(struct nvkm_clk *base)
300 {
301 	struct mcp77_clk *clk = mcp77_clk(base);
302 	struct nvkm_subdev *subdev = &clk->base.subdev;
303 	struct nvkm_device *device = subdev->device;
304 	u32 pllmask = 0, mast;
305 	unsigned long flags;
306 	unsigned long *f = &flags;
307 	int ret = 0;
308 
309 	ret = gt215_clk_pre(&clk->base, f);
310 	if (ret)
311 		goto out;
312 
313 	/* First switch to safe clocks: href */
314 	mast = nvkm_mask(device, 0xc054, 0x03400e70, 0x03400640);
315 	mast &= ~0x00400e73;
316 	mast |= 0x03000000;
317 
318 	switch (clk->csrc) {
319 	case nv_clk_src_hclkm4:
320 		nvkm_mask(device, 0x4028, 0x00070000, clk->cctrl);
321 		mast |= 0x00000002;
322 		break;
323 	case nv_clk_src_core:
324 		nvkm_wr32(device, 0x402c, clk->ccoef);
325 		nvkm_wr32(device, 0x4028, 0x80000000 | clk->cctrl);
326 		nvkm_wr32(device, 0x4040, clk->cpost);
327 		pllmask |= (0x3 << 8);
328 		mast |= 0x00000003;
329 		break;
330 	default:
331 		nvkm_warn(subdev, "Reclocking failed: unknown core clock\n");
332 		goto resume;
333 	}
334 
335 	switch (clk->ssrc) {
336 	case nv_clk_src_href:
337 		nvkm_mask(device, 0x4020, 0x00070000, 0x00000000);
338 		/* mast |= 0x00000000; */
339 		break;
340 	case nv_clk_src_core:
341 		nvkm_mask(device, 0x4020, 0x00070000, clk->sctrl);
342 		mast |= 0x00000020;
343 		break;
344 	case nv_clk_src_shader:
345 		nvkm_wr32(device, 0x4024, clk->scoef);
346 		nvkm_wr32(device, 0x4020, 0x80000000 | clk->sctrl);
347 		nvkm_wr32(device, 0x4070, clk->spost);
348 		pllmask |= (0x3 << 12);
349 		mast |= 0x00000030;
350 		break;
351 	default:
352 		nvkm_warn(subdev, "Reclocking failed: unknown sclk clock\n");
353 		goto resume;
354 	}
355 
356 	if (nvkm_msec(device, 2000,
357 		u32 tmp = nvkm_rd32(device, 0x004080) & pllmask;
358 		if (tmp == pllmask)
359 			break;
360 	) < 0)
361 		goto resume;
362 
363 	switch (clk->vsrc) {
364 	case nv_clk_src_cclk:
365 		mast |= 0x00400000;
366 		/* fall through */
367 	default:
368 		nvkm_wr32(device, 0x4600, clk->vdiv);
369 	}
370 
371 	nvkm_wr32(device, 0xc054, mast);
372 
373 resume:
374 	/* Disable some PLLs and dividers when unused */
375 	if (clk->csrc != nv_clk_src_core) {
376 		nvkm_wr32(device, 0x4040, 0x00000000);
377 		nvkm_mask(device, 0x4028, 0x80000000, 0x00000000);
378 	}
379 
380 	if (clk->ssrc != nv_clk_src_shader) {
381 		nvkm_wr32(device, 0x4070, 0x00000000);
382 		nvkm_mask(device, 0x4020, 0x80000000, 0x00000000);
383 	}
384 
385 out:
386 	if (ret == -EBUSY)
387 		f = NULL;
388 
389 	gt215_clk_post(&clk->base, f);
390 	return ret;
391 }
392 
393 static void
394 mcp77_clk_tidy(struct nvkm_clk *base)
395 {
396 }
397 
398 static const struct nvkm_clk_func
399 mcp77_clk = {
400 	.read = mcp77_clk_read,
401 	.calc = mcp77_clk_calc,
402 	.prog = mcp77_clk_prog,
403 	.tidy = mcp77_clk_tidy,
404 	.domains = {
405 		{ nv_clk_src_crystal, 0xff },
406 		{ nv_clk_src_href   , 0xff },
407 		{ nv_clk_src_core   , 0xff, 0, "core", 1000 },
408 		{ nv_clk_src_shader , 0xff, 0, "shader", 1000 },
409 		{ nv_clk_src_vdec   , 0xff, 0, "vdec", 1000 },
410 		{ nv_clk_src_max }
411 	}
412 };
413 
414 int
415 mcp77_clk_new(struct nvkm_device *device, int index, struct nvkm_clk **pclk)
416 {
417 	struct mcp77_clk *clk;
418 
419 	if (!(clk = kzalloc(sizeof(*clk), GFP_KERNEL)))
420 		return -ENOMEM;
421 	*pclk = &clk->base;
422 
423 	return nvkm_clk_ctor(&mcp77_clk, device, index, true, &clk->base);
424 }
425