Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
[linux-2.6-microblaze.git] / drivers / clk / renesas / rcar-gen3-cpg.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * R-Car Gen3 Clock Pulse Generator
4  *
5  * Copyright (C) 2015-2018 Glider bvba
6  * Copyright (C) 2019 Renesas Electronics Corp.
7  *
8  * Based on clk-rcar-gen3.c
9  *
10  * Copyright (C) 2015 Renesas Electronics Corp.
11  */
12
13 #include <linux/bug.h>
14 #include <linux/bitfield.h>
15 #include <linux/clk.h>
16 #include <linux/clk-provider.h>
17 #include <linux/device.h>
18 #include <linux/err.h>
19 #include <linux/init.h>
20 #include <linux/io.h>
21 #include <linux/pm.h>
22 #include <linux/slab.h>
23 #include <linux/sys_soc.h>
24
25 #include "renesas-cpg-mssr.h"
26 #include "rcar-cpg-lib.h"
27 #include "rcar-gen3-cpg.h"
28
29 #define CPG_PLLECR              0x00d0  /* PLL Enable Control Register */
30
31 #define CPG_PLLECR_PLLST(n)     BIT(8 + (n))    /* PLLn Circuit Status */
32
33 #define CPG_PLL0CR              0x00d8  /* PLLn Control Registers */
34 #define CPG_PLL2CR              0x002c
35 #define CPG_PLL4CR              0x01f4
36
37 #define CPG_PLLnCR_STC_MASK     GENMASK(30, 24) /* PLL Circuit Mult. Ratio */
38
39 #define CPG_RCKCR_CKSEL BIT(15) /* RCLK Clock Source Select */
40
41 /* PLL Clocks */
42 struct cpg_pll_clk {
43         struct clk_hw hw;
44         void __iomem *pllcr_reg;
45         void __iomem *pllecr_reg;
46         unsigned int fixed_mult;
47         u32 pllecr_pllst_mask;
48 };
49
50 #define to_pll_clk(_hw)   container_of(_hw, struct cpg_pll_clk, hw)
51
52 static unsigned long cpg_pll_clk_recalc_rate(struct clk_hw *hw,
53                                              unsigned long parent_rate)
54 {
55         struct cpg_pll_clk *pll_clk = to_pll_clk(hw);
56         unsigned int mult;
57         u32 val;
58
59         val = readl(pll_clk->pllcr_reg) & CPG_PLLnCR_STC_MASK;
60         mult = (val >> __ffs(CPG_PLLnCR_STC_MASK)) + 1;
61
62         return parent_rate * mult * pll_clk->fixed_mult;
63 }
64
65 static int cpg_pll_clk_determine_rate(struct clk_hw *hw,
66                                       struct clk_rate_request *req)
67 {
68         struct cpg_pll_clk *pll_clk = to_pll_clk(hw);
69         unsigned int min_mult, max_mult, mult;
70         unsigned long prate;
71
72         prate = req->best_parent_rate * pll_clk->fixed_mult;
73         min_mult = max(div64_ul(req->min_rate, prate), 1ULL);
74         max_mult = min(div64_ul(req->max_rate, prate), 128ULL);
75         if (max_mult < min_mult)
76                 return -EINVAL;
77
78         mult = DIV_ROUND_CLOSEST_ULL(req->rate, prate);
79         mult = clamp(mult, min_mult, max_mult);
80
81         req->rate = prate * mult;
82         return 0;
83 }
84
85 static int cpg_pll_clk_set_rate(struct clk_hw *hw, unsigned long rate,
86                                 unsigned long parent_rate)
87 {
88         struct cpg_pll_clk *pll_clk = to_pll_clk(hw);
89         unsigned int mult, i;
90         u32 val;
91
92         mult = DIV_ROUND_CLOSEST_ULL(rate, parent_rate * pll_clk->fixed_mult);
93         mult = clamp(mult, 1U, 128U);
94
95         val = readl(pll_clk->pllcr_reg);
96         val &= ~CPG_PLLnCR_STC_MASK;
97         val |= (mult - 1) << __ffs(CPG_PLLnCR_STC_MASK);
98         writel(val, pll_clk->pllcr_reg);
99
100         for (i = 1000; i; i--) {
101                 if (readl(pll_clk->pllecr_reg) & pll_clk->pllecr_pllst_mask)
102                         return 0;
103
104                 cpu_relax();
105         }
106
107         return -ETIMEDOUT;
108 }
109
110 static const struct clk_ops cpg_pll_clk_ops = {
111         .recalc_rate = cpg_pll_clk_recalc_rate,
112         .determine_rate = cpg_pll_clk_determine_rate,
113         .set_rate = cpg_pll_clk_set_rate,
114 };
115
116 static struct clk * __init cpg_pll_clk_register(const char *name,
117                                                 const char *parent_name,
118                                                 void __iomem *base,
119                                                 unsigned int mult,
120                                                 unsigned int offset,
121                                                 unsigned int index)
122
123 {
124         struct cpg_pll_clk *pll_clk;
125         struct clk_init_data init = {};
126         struct clk *clk;
127
128         pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL);
129         if (!pll_clk)
130                 return ERR_PTR(-ENOMEM);
131
132         init.name = name;
133         init.ops = &cpg_pll_clk_ops;
134         init.parent_names = &parent_name;
135         init.num_parents = 1;
136
137         pll_clk->hw.init = &init;
138         pll_clk->pllcr_reg = base + offset;
139         pll_clk->pllecr_reg = base + CPG_PLLECR;
140         pll_clk->fixed_mult = mult;     /* PLL refclk x (setting + 1) x mult */
141         pll_clk->pllecr_pllst_mask = CPG_PLLECR_PLLST(index);
142
143         clk = clk_register(NULL, &pll_clk->hw);
144         if (IS_ERR(clk))
145                 kfree(pll_clk);
146
147         return clk;
148 }
149
150 /*
151  * Z Clock & Z2 Clock
152  *
153  * Traits of this clock:
154  * prepare - clk_prepare only ensures that parents are prepared
155  * enable - clk_enable only ensures that parents are enabled
156  * rate - rate is adjustable.
157  *        clk->rate = (parent->rate * mult / 32 ) / fixed_div
158  * parent - fixed parent.  No clk_set_parent support
159  */
160 #define CPG_FRQCRB                      0x00000004
161 #define CPG_FRQCRB_KICK                 BIT(31)
162 #define CPG_FRQCRC                      0x000000e0
163
164 struct cpg_z_clk {
165         struct clk_hw hw;
166         void __iomem *reg;
167         void __iomem *kick_reg;
168         unsigned long max_rate;         /* Maximum rate for normal mode */
169         unsigned int fixed_div;
170         u32 mask;
171 };
172
173 #define to_z_clk(_hw)   container_of(_hw, struct cpg_z_clk, hw)
174
175 static unsigned long cpg_z_clk_recalc_rate(struct clk_hw *hw,
176                                            unsigned long parent_rate)
177 {
178         struct cpg_z_clk *zclk = to_z_clk(hw);
179         unsigned int mult;
180         u32 val;
181
182         val = readl(zclk->reg) & zclk->mask;
183         mult = 32 - (val >> __ffs(zclk->mask));
184
185         return DIV_ROUND_CLOSEST_ULL((u64)parent_rate * mult,
186                                      32 * zclk->fixed_div);
187 }
188
189 static int cpg_z_clk_determine_rate(struct clk_hw *hw,
190                                     struct clk_rate_request *req)
191 {
192         struct cpg_z_clk *zclk = to_z_clk(hw);
193         unsigned int min_mult, max_mult, mult;
194         unsigned long rate, prate;
195
196         rate = min(req->rate, req->max_rate);
197         if (rate <= zclk->max_rate) {
198                 /* Set parent rate to initial value for normal modes */
199                 prate = zclk->max_rate;
200         } else {
201                 /* Set increased parent rate for boost modes */
202                 prate = rate;
203         }
204         req->best_parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw),
205                                                   prate * zclk->fixed_div);
206
207         prate = req->best_parent_rate / zclk->fixed_div;
208         min_mult = max(div64_ul(req->min_rate * 32ULL, prate), 1ULL);
209         max_mult = min(div64_ul(req->max_rate * 32ULL, prate), 32ULL);
210         if (max_mult < min_mult)
211                 return -EINVAL;
212
213         mult = DIV_ROUND_CLOSEST_ULL(rate * 32ULL, prate);
214         mult = clamp(mult, min_mult, max_mult);
215
216         req->rate = DIV_ROUND_CLOSEST_ULL((u64)prate * mult, 32);
217         return 0;
218 }
219
220 static int cpg_z_clk_set_rate(struct clk_hw *hw, unsigned long rate,
221                               unsigned long parent_rate)
222 {
223         struct cpg_z_clk *zclk = to_z_clk(hw);
224         unsigned int mult;
225         unsigned int i;
226
227         mult = DIV64_U64_ROUND_CLOSEST(rate * 32ULL * zclk->fixed_div,
228                                        parent_rate);
229         mult = clamp(mult, 1U, 32U);
230
231         if (readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
232                 return -EBUSY;
233
234         cpg_reg_modify(zclk->reg, zclk->mask, (32 - mult) << __ffs(zclk->mask));
235
236         /*
237          * Set KICK bit in FRQCRB to update hardware setting and wait for
238          * clock change completion.
239          */
240         cpg_reg_modify(zclk->kick_reg, 0, CPG_FRQCRB_KICK);
241
242         /*
243          * Note: There is no HW information about the worst case latency.
244          *
245          * Using experimental measurements, it seems that no more than
246          * ~10 iterations are needed, independently of the CPU rate.
247          * Since this value might be dependent on external xtal rate, pll1
248          * rate or even the other emulation clocks rate, use 1000 as a
249          * "super" safe value.
250          */
251         for (i = 1000; i; i--) {
252                 if (!(readl(zclk->kick_reg) & CPG_FRQCRB_KICK))
253                         return 0;
254
255                 cpu_relax();
256         }
257
258         return -ETIMEDOUT;
259 }
260
261 static const struct clk_ops cpg_z_clk_ops = {
262         .recalc_rate = cpg_z_clk_recalc_rate,
263         .determine_rate = cpg_z_clk_determine_rate,
264         .set_rate = cpg_z_clk_set_rate,
265 };
266
267 static struct clk * __init cpg_z_clk_register(const char *name,
268                                               const char *parent_name,
269                                               void __iomem *reg,
270                                               unsigned int div,
271                                               unsigned int offset)
272 {
273         struct clk_init_data init = {};
274         struct cpg_z_clk *zclk;
275         struct clk *clk;
276
277         zclk = kzalloc(sizeof(*zclk), GFP_KERNEL);
278         if (!zclk)
279                 return ERR_PTR(-ENOMEM);
280
281         init.name = name;
282         init.ops = &cpg_z_clk_ops;
283         init.flags = CLK_SET_RATE_PARENT;
284         init.parent_names = &parent_name;
285         init.num_parents = 1;
286
287         zclk->reg = reg + CPG_FRQCRC;
288         zclk->kick_reg = reg + CPG_FRQCRB;
289         zclk->hw.init = &init;
290         zclk->mask = GENMASK(offset + 4, offset);
291         zclk->fixed_div = div; /* PLLVCO x 1/div x SYS-CPU divider */
292
293         clk = clk_register(NULL, &zclk->hw);
294         if (IS_ERR(clk)) {
295                 kfree(zclk);
296                 return clk;
297         }
298
299         zclk->max_rate = clk_hw_get_rate(clk_hw_get_parent(&zclk->hw)) /
300                          zclk->fixed_div;
301         return clk;
302 }
303
304 struct rpc_clock {
305         struct clk_divider div;
306         struct clk_gate gate;
307         /*
308          * One notifier covers both RPC and RPCD2 clocks as they are both
309          * controlled by the same RPCCKCR register...
310          */
311         struct cpg_simple_notifier csn;
312 };
313
314 static const struct clk_div_table cpg_rpcsrc_div_table[] = {
315         { 2, 5 }, { 3, 6 }, { 0, 0 },
316 };
317
318 static const struct clk_div_table cpg_rpc_div_table[] = {
319         { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 }, { 0, 0 },
320 };
321
322 static struct clk * __init cpg_rpc_clk_register(const char *name,
323         void __iomem *base, const char *parent_name,
324         struct raw_notifier_head *notifiers)
325 {
326         struct rpc_clock *rpc;
327         struct clk *clk;
328
329         rpc = kzalloc(sizeof(*rpc), GFP_KERNEL);
330         if (!rpc)
331                 return ERR_PTR(-ENOMEM);
332
333         rpc->div.reg = base + CPG_RPCCKCR;
334         rpc->div.width = 3;
335         rpc->div.table = cpg_rpc_div_table;
336         rpc->div.lock = &cpg_lock;
337
338         rpc->gate.reg = base + CPG_RPCCKCR;
339         rpc->gate.bit_idx = 8;
340         rpc->gate.flags = CLK_GATE_SET_TO_DISABLE;
341         rpc->gate.lock = &cpg_lock;
342
343         rpc->csn.reg = base + CPG_RPCCKCR;
344
345         clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL,
346                                      &rpc->div.hw,  &clk_divider_ops,
347                                      &rpc->gate.hw, &clk_gate_ops,
348                                      CLK_SET_RATE_PARENT);
349         if (IS_ERR(clk)) {
350                 kfree(rpc);
351                 return clk;
352         }
353
354         cpg_simple_notifier_register(notifiers, &rpc->csn);
355         return clk;
356 }
357
358 struct rpcd2_clock {
359         struct clk_fixed_factor fixed;
360         struct clk_gate gate;
361 };
362
363 static struct clk * __init cpg_rpcd2_clk_register(const char *name,
364                                                   void __iomem *base,
365                                                   const char *parent_name)
366 {
367         struct rpcd2_clock *rpcd2;
368         struct clk *clk;
369
370         rpcd2 = kzalloc(sizeof(*rpcd2), GFP_KERNEL);
371         if (!rpcd2)
372                 return ERR_PTR(-ENOMEM);
373
374         rpcd2->fixed.mult = 1;
375         rpcd2->fixed.div = 2;
376
377         rpcd2->gate.reg = base + CPG_RPCCKCR;
378         rpcd2->gate.bit_idx = 9;
379         rpcd2->gate.flags = CLK_GATE_SET_TO_DISABLE;
380         rpcd2->gate.lock = &cpg_lock;
381
382         clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL,
383                                      &rpcd2->fixed.hw, &clk_fixed_factor_ops,
384                                      &rpcd2->gate.hw, &clk_gate_ops,
385                                      CLK_SET_RATE_PARENT);
386         if (IS_ERR(clk))
387                 kfree(rpcd2);
388
389         return clk;
390 }
391
392
393 static const struct rcar_gen3_cpg_pll_config *cpg_pll_config __initdata;
394 static unsigned int cpg_clk_extalr __initdata;
395 static u32 cpg_mode __initdata;
396 static u32 cpg_quirks __initdata;
397
398 #define PLL_ERRATA      BIT(0)          /* Missing PLL0/2/4 post-divider */
399 #define RCKCR_CKSEL     BIT(1)          /* Manual RCLK parent selection */
400 #define SD_SKIP_FIRST   BIT(2)          /* Skip first clock in SD table */
401
402
403 static const struct soc_device_attribute cpg_quirks_match[] __initconst = {
404         {
405                 .soc_id = "r8a7795", .revision = "ES1.0",
406                 .data = (void *)(PLL_ERRATA | RCKCR_CKSEL | SD_SKIP_FIRST),
407         },
408         {
409                 .soc_id = "r8a7795", .revision = "ES1.*",
410                 .data = (void *)(RCKCR_CKSEL | SD_SKIP_FIRST),
411         },
412         {
413                 .soc_id = "r8a7795", .revision = "ES2.0",
414                 .data = (void *)SD_SKIP_FIRST,
415         },
416         {
417                 .soc_id = "r8a7796", .revision = "ES1.0",
418                 .data = (void *)(RCKCR_CKSEL | SD_SKIP_FIRST),
419         },
420         {
421                 .soc_id = "r8a7796", .revision = "ES1.1",
422                 .data = (void *)SD_SKIP_FIRST,
423         },
424         { /* sentinel */ }
425 };
426
427 struct clk * __init rcar_gen3_cpg_clk_register(struct device *dev,
428         const struct cpg_core_clk *core, const struct cpg_mssr_info *info,
429         struct clk **clks, void __iomem *base,
430         struct raw_notifier_head *notifiers)
431 {
432         const struct clk *parent;
433         unsigned int mult = 1;
434         unsigned int div = 1;
435         u32 value;
436
437         parent = clks[core->parent & 0xffff];   /* some types use high bits */
438         if (IS_ERR(parent))
439                 return ERR_CAST(parent);
440
441         switch (core->type) {
442         case CLK_TYPE_GEN3_MAIN:
443                 div = cpg_pll_config->extal_div;
444                 break;
445
446         case CLK_TYPE_GEN3_PLL0:
447                 /*
448                  * PLL0 is implemented as a custom clock, to change the
449                  * multiplier when cpufreq changes between normal and boost
450                  * modes.
451                  */
452                 mult = (cpg_quirks & PLL_ERRATA) ? 4 : 2;
453                 return cpg_pll_clk_register(core->name, __clk_get_name(parent),
454                                             base, mult, CPG_PLL0CR, 0);
455
456         case CLK_TYPE_GEN3_PLL1:
457                 mult = cpg_pll_config->pll1_mult;
458                 div = cpg_pll_config->pll1_div;
459                 break;
460
461         case CLK_TYPE_GEN3_PLL2:
462                 /*
463                  * PLL2 is implemented as a custom clock, to change the
464                  * multiplier when cpufreq changes between normal and boost
465                  * modes.
466                  */
467                 mult = (cpg_quirks & PLL_ERRATA) ? 4 : 2;
468                 return cpg_pll_clk_register(core->name, __clk_get_name(parent),
469                                             base, mult, CPG_PLL2CR, 2);
470
471         case CLK_TYPE_GEN3_PLL3:
472                 mult = cpg_pll_config->pll3_mult;
473                 div = cpg_pll_config->pll3_div;
474                 break;
475
476         case CLK_TYPE_GEN3_PLL4:
477                 /*
478                  * PLL4 is a configurable multiplier clock. Register it as a
479                  * fixed factor clock for now as there's no generic multiplier
480                  * clock implementation and we currently have no need to change
481                  * the multiplier value.
482                  */
483                 value = readl(base + CPG_PLL4CR);
484                 mult = (((value >> 24) & 0x7f) + 1) * 2;
485                 if (cpg_quirks & PLL_ERRATA)
486                         mult *= 2;
487                 break;
488
489         case CLK_TYPE_GEN3_SD:
490                 return cpg_sd_clk_register(core->name, base, core->offset,
491                                            __clk_get_name(parent), notifiers,
492                                            cpg_quirks & SD_SKIP_FIRST);
493
494         case CLK_TYPE_GEN3_R:
495                 if (cpg_quirks & RCKCR_CKSEL) {
496                         struct cpg_simple_notifier *csn;
497
498                         csn = kzalloc(sizeof(*csn), GFP_KERNEL);
499                         if (!csn)
500                                 return ERR_PTR(-ENOMEM);
501
502                         csn->reg = base + CPG_RCKCR;
503
504                         /*
505                          * RINT is default.
506                          * Only if EXTALR is populated, we switch to it.
507                          */
508                         value = readl(csn->reg) & 0x3f;
509
510                         if (clk_get_rate(clks[cpg_clk_extalr])) {
511                                 parent = clks[cpg_clk_extalr];
512                                 value |= CPG_RCKCR_CKSEL;
513                         }
514
515                         writel(value, csn->reg);
516                         cpg_simple_notifier_register(notifiers, csn);
517                         break;
518                 }
519
520                 /* Select parent clock of RCLK by MD28 */
521                 if (cpg_mode & BIT(28))
522                         parent = clks[cpg_clk_extalr];
523                 break;
524
525         case CLK_TYPE_GEN3_MDSEL:
526                 /*
527                  * Clock selectable between two parents and two fixed dividers
528                  * using a mode pin
529                  */
530                 if (cpg_mode & BIT(core->offset)) {
531                         div = core->div & 0xffff;
532                 } else {
533                         parent = clks[core->parent >> 16];
534                         if (IS_ERR(parent))
535                                 return ERR_CAST(parent);
536                         div = core->div >> 16;
537                 }
538                 mult = 1;
539                 break;
540
541         case CLK_TYPE_GEN3_Z:
542                 return cpg_z_clk_register(core->name, __clk_get_name(parent),
543                                           base, core->div, core->offset);
544
545         case CLK_TYPE_GEN3_OSC:
546                 /*
547                  * Clock combining OSC EXTAL predivider and a fixed divider
548                  */
549                 div = cpg_pll_config->osc_prediv * core->div;
550                 break;
551
552         case CLK_TYPE_GEN3_RCKSEL:
553                 /*
554                  * Clock selectable between two parents and two fixed dividers
555                  * using RCKCR.CKSEL
556                  */
557                 if (readl(base + CPG_RCKCR) & CPG_RCKCR_CKSEL) {
558                         div = core->div & 0xffff;
559                 } else {
560                         parent = clks[core->parent >> 16];
561                         if (IS_ERR(parent))
562                                 return ERR_CAST(parent);
563                         div = core->div >> 16;
564                 }
565                 break;
566
567         case CLK_TYPE_GEN3_RPCSRC:
568                 return clk_register_divider_table(NULL, core->name,
569                                                   __clk_get_name(parent), 0,
570                                                   base + CPG_RPCCKCR, 3, 2, 0,
571                                                   cpg_rpcsrc_div_table,
572                                                   &cpg_lock);
573
574         case CLK_TYPE_GEN3_E3_RPCSRC:
575                 /*
576                  * Register RPCSRC as fixed factor clock based on the
577                  * MD[4:1] pins and CPG_RPCCKCR[4:3] register value for
578                  * which has been set prior to booting the kernel.
579                  */
580                 value = (readl(base + CPG_RPCCKCR) & GENMASK(4, 3)) >> 3;
581
582                 switch (value) {
583                 case 0:
584                         div = 5;
585                         break;
586                 case 1:
587                         div = 3;
588                         break;
589                 case 2:
590                         parent = clks[core->parent >> 16];
591                         if (IS_ERR(parent))
592                                 return ERR_CAST(parent);
593                         div = core->div;
594                         break;
595                 case 3:
596                 default:
597                         div = 2;
598                         break;
599                 }
600                 break;
601
602         case CLK_TYPE_GEN3_RPC:
603                 return cpg_rpc_clk_register(core->name, base,
604                                             __clk_get_name(parent), notifiers);
605
606         case CLK_TYPE_GEN3_RPCD2:
607                 return cpg_rpcd2_clk_register(core->name, base,
608                                               __clk_get_name(parent));
609
610         default:
611                 return ERR_PTR(-EINVAL);
612         }
613
614         return clk_register_fixed_factor(NULL, core->name,
615                                          __clk_get_name(parent), 0, mult, div);
616 }
617
618 int __init rcar_gen3_cpg_init(const struct rcar_gen3_cpg_pll_config *config,
619                               unsigned int clk_extalr, u32 mode)
620 {
621         const struct soc_device_attribute *attr;
622
623         cpg_pll_config = config;
624         cpg_clk_extalr = clk_extalr;
625         cpg_mode = mode;
626         attr = soc_device_match(cpg_quirks_match);
627         if (attr)
628                 cpg_quirks = (uintptr_t)attr->data;
629         pr_debug("%s: mode = 0x%x quirks = 0x%x\n", __func__, mode, cpg_quirks);
630
631         spin_lock_init(&cpg_lock);
632
633         return 0;
634 }