xref: /openbmc/linux/arch/arm/mm/cache-uniphier.c (revision d774a589)
1 /*
2  * Copyright (C) 2015-2016 Socionext Inc.
3  *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15 
16 #define pr_fmt(fmt)		"uniphier: " fmt
17 
18 #include <linux/init.h>
19 #include <linux/io.h>
20 #include <linux/log2.h>
21 #include <linux/of_address.h>
22 #include <linux/slab.h>
23 #include <asm/hardware/cache-uniphier.h>
24 #include <asm/outercache.h>
25 
26 /* control registers */
27 #define UNIPHIER_SSCC		0x0	/* Control Register */
28 #define    UNIPHIER_SSCC_BST			BIT(20)	/* UCWG burst read */
29 #define    UNIPHIER_SSCC_ACT			BIT(19)	/* Inst-Data separate */
30 #define    UNIPHIER_SSCC_WTG			BIT(18)	/* WT gathering on */
31 #define    UNIPHIER_SSCC_PRD			BIT(17)	/* enable pre-fetch */
32 #define    UNIPHIER_SSCC_ON			BIT(0)	/* enable cache */
33 #define UNIPHIER_SSCLPDAWCR	0x30	/* Unified/Data Active Way Control */
34 #define UNIPHIER_SSCLPIAWCR	0x34	/* Instruction Active Way Control */
35 
36 /* revision registers */
37 #define UNIPHIER_SSCID		0x0	/* ID Register */
38 
39 /* operation registers */
40 #define UNIPHIER_SSCOPE		0x244	/* Cache Operation Primitive Entry */
41 #define    UNIPHIER_SSCOPE_CM_INV		0x0	/* invalidate */
42 #define    UNIPHIER_SSCOPE_CM_CLEAN		0x1	/* clean */
43 #define    UNIPHIER_SSCOPE_CM_FLUSH		0x2	/* flush */
44 #define    UNIPHIER_SSCOPE_CM_SYNC		0x8	/* sync (drain bufs) */
45 #define    UNIPHIER_SSCOPE_CM_FLUSH_PREFETCH	0x9	/* flush p-fetch buf */
46 #define UNIPHIER_SSCOQM		0x248	/* Cache Operation Queue Mode */
47 #define    UNIPHIER_SSCOQM_S_MASK		(0x3 << 17)
48 #define    UNIPHIER_SSCOQM_S_RANGE		(0x0 << 17)
49 #define    UNIPHIER_SSCOQM_S_ALL		(0x1 << 17)
50 #define    UNIPHIER_SSCOQM_CE			BIT(15)	/* notify completion */
51 #define    UNIPHIER_SSCOQM_CM_INV		0x0	/* invalidate */
52 #define    UNIPHIER_SSCOQM_CM_CLEAN		0x1	/* clean */
53 #define    UNIPHIER_SSCOQM_CM_FLUSH		0x2	/* flush */
54 #define UNIPHIER_SSCOQAD	0x24c	/* Cache Operation Queue Address */
55 #define UNIPHIER_SSCOQSZ	0x250	/* Cache Operation Queue Size */
56 #define UNIPHIER_SSCOPPQSEF	0x25c	/* Cache Operation Queue Set Complete*/
57 #define    UNIPHIER_SSCOPPQSEF_FE		BIT(1)
58 #define    UNIPHIER_SSCOPPQSEF_OE		BIT(0)
59 #define UNIPHIER_SSCOLPQS	0x260	/* Cache Operation Queue Status */
60 #define    UNIPHIER_SSCOLPQS_EF			BIT(2)
61 #define    UNIPHIER_SSCOLPQS_EST		BIT(1)
62 #define    UNIPHIER_SSCOLPQS_QST		BIT(0)
63 
64 /* Is the operation region specified by address range? */
65 #define UNIPHIER_SSCOQM_S_IS_RANGE(op) \
66 		((op & UNIPHIER_SSCOQM_S_MASK) == UNIPHIER_SSCOQM_S_RANGE)
67 
68 /**
69  * uniphier_cache_data - UniPhier outer cache specific data
70  *
71  * @ctrl_base: virtual base address of control registers
72  * @rev_base: virtual base address of revision registers
73  * @op_base: virtual base address of operation registers
74  * @way_present_mask: each bit specifies if the way is present
75  * @way_locked_mask: each bit specifies if the way is locked
76  * @nsets: number of associativity sets
77  * @line_size: line size in bytes
78  * @range_op_max_size: max size that can be handled by a single range operation
79  * @list: list node to include this level in the whole cache hierarchy
80  */
81 struct uniphier_cache_data {
82 	void __iomem *ctrl_base;
83 	void __iomem *rev_base;
84 	void __iomem *op_base;
85 	void __iomem *way_ctrl_base;
86 	u32 way_present_mask;
87 	u32 way_locked_mask;
88 	u32 nsets;
89 	u32 line_size;
90 	u32 range_op_max_size;
91 	struct list_head list;
92 };
93 
94 /*
95  * List of the whole outer cache hierarchy.  This list is only modified during
96  * the early boot stage, so no mutex is taken for the access to the list.
97  */
98 static LIST_HEAD(uniphier_cache_list);
99 
100 /**
101  * __uniphier_cache_sync - perform a sync point for a particular cache level
102  *
103  * @data: cache controller specific data
104  */
105 static void __uniphier_cache_sync(struct uniphier_cache_data *data)
106 {
107 	/* This sequence need not be atomic.  Do not disable IRQ. */
108 	writel_relaxed(UNIPHIER_SSCOPE_CM_SYNC,
109 		       data->op_base + UNIPHIER_SSCOPE);
110 	/* need a read back to confirm */
111 	readl_relaxed(data->op_base + UNIPHIER_SSCOPE);
112 }
113 
114 /**
115  * __uniphier_cache_maint_common - run a queue operation for a particular level
116  *
117  * @data: cache controller specific data
118  * @start: start address of range operation (don't care for "all" operation)
119  * @size: data size of range operation (don't care for "all" operation)
120  * @operation: flags to specify the desired cache operation
121  */
122 static void __uniphier_cache_maint_common(struct uniphier_cache_data *data,
123 					  unsigned long start,
124 					  unsigned long size,
125 					  u32 operation)
126 {
127 	unsigned long flags;
128 
129 	/*
130 	 * No spin lock is necessary here because:
131 	 *
132 	 * [1] This outer cache controller is able to accept maintenance
133 	 * operations from multiple CPUs at a time in an SMP system; if a
134 	 * maintenance operation is under way and another operation is issued,
135 	 * the new one is stored in the queue.  The controller performs one
136 	 * operation after another.  If the queue is full, the status register,
137 	 * UNIPHIER_SSCOPPQSEF, indicates that the queue registration has
138 	 * failed.  The status registers, UNIPHIER_{SSCOPPQSEF, SSCOLPQS}, have
139 	 * different instances for each CPU, i.e. each CPU can track the status
140 	 * of the maintenance operations triggered by itself.
141 	 *
142 	 * [2] The cache command registers, UNIPHIER_{SSCOQM, SSCOQAD, SSCOQSZ,
143 	 * SSCOQWN}, are shared between multiple CPUs, but the hardware still
144 	 * guarantees the registration sequence is atomic; the write access to
145 	 * them are arbitrated by the hardware.  The first accessor to the
146 	 * register, UNIPHIER_SSCOQM, holds the access right and it is released
147 	 * by reading the status register, UNIPHIER_SSCOPPQSEF.  While one CPU
148 	 * is holding the access right, other CPUs fail to register operations.
149 	 * One CPU should not hold the access right for a long time, so local
150 	 * IRQs should be disabled while the following sequence.
151 	 */
152 	local_irq_save(flags);
153 
154 	/* clear the complete notification flag */
155 	writel_relaxed(UNIPHIER_SSCOLPQS_EF, data->op_base + UNIPHIER_SSCOLPQS);
156 
157 	do {
158 		/* set cache operation */
159 		writel_relaxed(UNIPHIER_SSCOQM_CE | operation,
160 			       data->op_base + UNIPHIER_SSCOQM);
161 
162 		/* set address range if needed */
163 		if (likely(UNIPHIER_SSCOQM_S_IS_RANGE(operation))) {
164 			writel_relaxed(start, data->op_base + UNIPHIER_SSCOQAD);
165 			writel_relaxed(size, data->op_base + UNIPHIER_SSCOQSZ);
166 		}
167 	} while (unlikely(readl_relaxed(data->op_base + UNIPHIER_SSCOPPQSEF) &
168 			  (UNIPHIER_SSCOPPQSEF_FE | UNIPHIER_SSCOPPQSEF_OE)));
169 
170 	/* wait until the operation is completed */
171 	while (likely(readl_relaxed(data->op_base + UNIPHIER_SSCOLPQS) !=
172 		      UNIPHIER_SSCOLPQS_EF))
173 		cpu_relax();
174 
175 	local_irq_restore(flags);
176 }
177 
178 static void __uniphier_cache_maint_all(struct uniphier_cache_data *data,
179 				       u32 operation)
180 {
181 	__uniphier_cache_maint_common(data, 0, 0,
182 				      UNIPHIER_SSCOQM_S_ALL | operation);
183 
184 	__uniphier_cache_sync(data);
185 }
186 
187 static void __uniphier_cache_maint_range(struct uniphier_cache_data *data,
188 					 unsigned long start, unsigned long end,
189 					 u32 operation)
190 {
191 	unsigned long size;
192 
193 	/*
194 	 * If the start address is not aligned,
195 	 * perform a cache operation for the first cache-line
196 	 */
197 	start = start & ~(data->line_size - 1);
198 
199 	size = end - start;
200 
201 	if (unlikely(size >= (unsigned long)(-data->line_size))) {
202 		/* this means cache operation for all range */
203 		__uniphier_cache_maint_all(data, operation);
204 		return;
205 	}
206 
207 	/*
208 	 * If the end address is not aligned,
209 	 * perform a cache operation for the last cache-line
210 	 */
211 	size = ALIGN(size, data->line_size);
212 
213 	while (size) {
214 		unsigned long chunk_size = min_t(unsigned long, size,
215 						 data->range_op_max_size);
216 
217 		__uniphier_cache_maint_common(data, start, chunk_size,
218 					UNIPHIER_SSCOQM_S_RANGE | operation);
219 
220 		start += chunk_size;
221 		size -= chunk_size;
222 	}
223 
224 	__uniphier_cache_sync(data);
225 }
226 
227 static void __uniphier_cache_enable(struct uniphier_cache_data *data, bool on)
228 {
229 	u32 val = 0;
230 
231 	if (on)
232 		val = UNIPHIER_SSCC_WTG | UNIPHIER_SSCC_PRD | UNIPHIER_SSCC_ON;
233 
234 	writel_relaxed(val, data->ctrl_base + UNIPHIER_SSCC);
235 }
236 
237 static void __init __uniphier_cache_set_locked_ways(
238 					struct uniphier_cache_data *data,
239 					u32 way_mask)
240 {
241 	unsigned int cpu;
242 
243 	data->way_locked_mask = way_mask & data->way_present_mask;
244 
245 	for_each_possible_cpu(cpu)
246 		writel_relaxed(~data->way_locked_mask & data->way_present_mask,
247 			       data->way_ctrl_base + 4 * cpu);
248 }
249 
250 static void uniphier_cache_maint_range(unsigned long start, unsigned long end,
251 				       u32 operation)
252 {
253 	struct uniphier_cache_data *data;
254 
255 	list_for_each_entry(data, &uniphier_cache_list, list)
256 		__uniphier_cache_maint_range(data, start, end, operation);
257 }
258 
259 static void uniphier_cache_maint_all(u32 operation)
260 {
261 	struct uniphier_cache_data *data;
262 
263 	list_for_each_entry(data, &uniphier_cache_list, list)
264 		__uniphier_cache_maint_all(data, operation);
265 }
266 
267 static void uniphier_cache_inv_range(unsigned long start, unsigned long end)
268 {
269 	uniphier_cache_maint_range(start, end, UNIPHIER_SSCOQM_CM_INV);
270 }
271 
272 static void uniphier_cache_clean_range(unsigned long start, unsigned long end)
273 {
274 	uniphier_cache_maint_range(start, end, UNIPHIER_SSCOQM_CM_CLEAN);
275 }
276 
277 static void uniphier_cache_flush_range(unsigned long start, unsigned long end)
278 {
279 	uniphier_cache_maint_range(start, end, UNIPHIER_SSCOQM_CM_FLUSH);
280 }
281 
282 static void __init uniphier_cache_inv_all(void)
283 {
284 	uniphier_cache_maint_all(UNIPHIER_SSCOQM_CM_INV);
285 }
286 
287 static void uniphier_cache_flush_all(void)
288 {
289 	uniphier_cache_maint_all(UNIPHIER_SSCOQM_CM_FLUSH);
290 }
291 
292 static void uniphier_cache_disable(void)
293 {
294 	struct uniphier_cache_data *data;
295 
296 	list_for_each_entry_reverse(data, &uniphier_cache_list, list)
297 		__uniphier_cache_enable(data, false);
298 
299 	uniphier_cache_flush_all();
300 }
301 
302 static void __init uniphier_cache_enable(void)
303 {
304 	struct uniphier_cache_data *data;
305 
306 	uniphier_cache_inv_all();
307 
308 	list_for_each_entry(data, &uniphier_cache_list, list) {
309 		__uniphier_cache_enable(data, true);
310 		__uniphier_cache_set_locked_ways(data, 0);
311 	}
312 }
313 
314 static void uniphier_cache_sync(void)
315 {
316 	struct uniphier_cache_data *data;
317 
318 	list_for_each_entry(data, &uniphier_cache_list, list)
319 		__uniphier_cache_sync(data);
320 }
321 
322 static const struct of_device_id uniphier_cache_match[] __initconst = {
323 	{ .compatible = "socionext,uniphier-system-cache" },
324 	{ /* sentinel */ }
325 };
326 
327 static int __init __uniphier_cache_init(struct device_node *np,
328 					unsigned int *cache_level)
329 {
330 	struct uniphier_cache_data *data;
331 	u32 level, cache_size;
332 	struct device_node *next_np;
333 	int ret = 0;
334 
335 	if (!of_match_node(uniphier_cache_match, np)) {
336 		pr_err("L%d: not compatible with uniphier cache\n",
337 		       *cache_level);
338 		return -EINVAL;
339 	}
340 
341 	if (of_property_read_u32(np, "cache-level", &level)) {
342 		pr_err("L%d: cache-level is not specified\n", *cache_level);
343 		return -EINVAL;
344 	}
345 
346 	if (level != *cache_level) {
347 		pr_err("L%d: cache-level is unexpected value %d\n",
348 		       *cache_level, level);
349 		return -EINVAL;
350 	}
351 
352 	if (!of_property_read_bool(np, "cache-unified")) {
353 		pr_err("L%d: cache-unified is not specified\n", *cache_level);
354 		return -EINVAL;
355 	}
356 
357 	data = kzalloc(sizeof(*data), GFP_KERNEL);
358 	if (!data)
359 		return -ENOMEM;
360 
361 	if (of_property_read_u32(np, "cache-line-size", &data->line_size) ||
362 	    !is_power_of_2(data->line_size)) {
363 		pr_err("L%d: cache-line-size is unspecified or invalid\n",
364 		       *cache_level);
365 		ret = -EINVAL;
366 		goto err;
367 	}
368 
369 	if (of_property_read_u32(np, "cache-sets", &data->nsets) ||
370 	    !is_power_of_2(data->nsets)) {
371 		pr_err("L%d: cache-sets is unspecified or invalid\n",
372 		       *cache_level);
373 		ret = -EINVAL;
374 		goto err;
375 	}
376 
377 	if (of_property_read_u32(np, "cache-size", &cache_size) ||
378 	    cache_size == 0 || cache_size % (data->nsets * data->line_size)) {
379 		pr_err("L%d: cache-size is unspecified or invalid\n",
380 		       *cache_level);
381 		ret = -EINVAL;
382 		goto err;
383 	}
384 
385 	data->way_present_mask =
386 		((u32)1 << cache_size / data->nsets / data->line_size) - 1;
387 
388 	data->ctrl_base = of_iomap(np, 0);
389 	if (!data->ctrl_base) {
390 		pr_err("L%d: failed to map control register\n", *cache_level);
391 		ret = -ENOMEM;
392 		goto err;
393 	}
394 
395 	data->rev_base = of_iomap(np, 1);
396 	if (!data->rev_base) {
397 		pr_err("L%d: failed to map revision register\n", *cache_level);
398 		ret = -ENOMEM;
399 		goto err;
400 	}
401 
402 	data->op_base = of_iomap(np, 2);
403 	if (!data->op_base) {
404 		pr_err("L%d: failed to map operation register\n", *cache_level);
405 		ret = -ENOMEM;
406 		goto err;
407 	}
408 
409 	data->way_ctrl_base = data->ctrl_base + 0xc00;
410 
411 	if (*cache_level == 2) {
412 		u32 revision = readl(data->rev_base + UNIPHIER_SSCID);
413 		/*
414 		 * The size of range operation is limited to (1 << 22) or less
415 		 * for PH-sLD8 or older SoCs.
416 		 */
417 		if (revision <= 0x16)
418 			data->range_op_max_size = (u32)1 << 22;
419 
420 		/*
421 		 * Unfortunatly, the offset address of active way control base
422 		 * varies from SoC to SoC.
423 		 */
424 		switch (revision) {
425 		case 0x11:	/* sLD3 */
426 			data->way_ctrl_base = data->ctrl_base + 0x870;
427 			break;
428 		case 0x12:	/* LD4 */
429 		case 0x16:	/* sld8 */
430 			data->way_ctrl_base = data->ctrl_base + 0x840;
431 			break;
432 		default:
433 			break;
434 		}
435 	}
436 
437 	data->range_op_max_size -= data->line_size;
438 
439 	INIT_LIST_HEAD(&data->list);
440 	list_add_tail(&data->list, &uniphier_cache_list); /* no mutex */
441 
442 	/*
443 	 * OK, this level has been successfully initialized.  Look for the next
444 	 * level cache.  Do not roll back even if the initialization of the
445 	 * next level cache fails because we want to continue with available
446 	 * cache levels.
447 	 */
448 	next_np = of_find_next_cache_node(np);
449 	if (next_np) {
450 		(*cache_level)++;
451 		ret = __uniphier_cache_init(next_np, cache_level);
452 	}
453 	of_node_put(next_np);
454 
455 	return ret;
456 err:
457 	iounmap(data->op_base);
458 	iounmap(data->rev_base);
459 	iounmap(data->ctrl_base);
460 	kfree(data);
461 
462 	return ret;
463 }
464 
465 int __init uniphier_cache_init(void)
466 {
467 	struct device_node *np = NULL;
468 	unsigned int cache_level;
469 	int ret = 0;
470 
471 	/* look for level 2 cache */
472 	while ((np = of_find_matching_node(np, uniphier_cache_match)))
473 		if (!of_property_read_u32(np, "cache-level", &cache_level) &&
474 		    cache_level == 2)
475 			break;
476 
477 	if (!np)
478 		return -ENODEV;
479 
480 	ret = __uniphier_cache_init(np, &cache_level);
481 	of_node_put(np);
482 
483 	if (ret) {
484 		/*
485 		 * Error out iif L2 initialization fails.  Continue with any
486 		 * error on L3 or outer because they are optional.
487 		 */
488 		if (cache_level == 2) {
489 			pr_err("failed to initialize L2 cache\n");
490 			return ret;
491 		}
492 
493 		cache_level--;
494 		ret = 0;
495 	}
496 
497 	outer_cache.inv_range = uniphier_cache_inv_range;
498 	outer_cache.clean_range = uniphier_cache_clean_range;
499 	outer_cache.flush_range = uniphier_cache_flush_range;
500 	outer_cache.flush_all = uniphier_cache_flush_all;
501 	outer_cache.disable = uniphier_cache_disable;
502 	outer_cache.sync = uniphier_cache_sync;
503 
504 	uniphier_cache_enable();
505 
506 	pr_info("enabled outer cache (cache level: %d)\n", cache_level);
507 
508 	return ret;
509 }
510