xref: /openbmc/linux/arch/arm/mm/cache-uniphier.c (revision e2c75e76)
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/bitops.h>
19 #include <linux/init.h>
20 #include <linux/io.h>
21 #include <linux/log2.h>
22 #include <linux/of_address.h>
23 #include <linux/slab.h>
24 #include <asm/hardware/cache-uniphier.h>
25 #include <asm/outercache.h>
26 
27 /* control registers */
28 #define UNIPHIER_SSCC		0x0	/* Control Register */
29 #define    UNIPHIER_SSCC_BST			BIT(20)	/* UCWG burst read */
30 #define    UNIPHIER_SSCC_ACT			BIT(19)	/* Inst-Data separate */
31 #define    UNIPHIER_SSCC_WTG			BIT(18)	/* WT gathering on */
32 #define    UNIPHIER_SSCC_PRD			BIT(17)	/* enable pre-fetch */
33 #define    UNIPHIER_SSCC_ON			BIT(0)	/* enable cache */
34 #define UNIPHIER_SSCLPDAWCR	0x30	/* Unified/Data Active Way Control */
35 #define UNIPHIER_SSCLPIAWCR	0x34	/* Instruction Active Way Control */
36 
37 /* revision registers */
38 #define UNIPHIER_SSCID		0x0	/* ID Register */
39 
40 /* operation registers */
41 #define UNIPHIER_SSCOPE		0x244	/* Cache Operation Primitive Entry */
42 #define    UNIPHIER_SSCOPE_CM_INV		0x0	/* invalidate */
43 #define    UNIPHIER_SSCOPE_CM_CLEAN		0x1	/* clean */
44 #define    UNIPHIER_SSCOPE_CM_FLUSH		0x2	/* flush */
45 #define    UNIPHIER_SSCOPE_CM_SYNC		0x8	/* sync (drain bufs) */
46 #define    UNIPHIER_SSCOPE_CM_FLUSH_PREFETCH	0x9	/* flush p-fetch buf */
47 #define UNIPHIER_SSCOQM		0x248	/* Cache Operation Queue Mode */
48 #define    UNIPHIER_SSCOQM_S_MASK		(0x3 << 17)
49 #define    UNIPHIER_SSCOQM_S_RANGE		(0x0 << 17)
50 #define    UNIPHIER_SSCOQM_S_ALL		(0x1 << 17)
51 #define    UNIPHIER_SSCOQM_CE			BIT(15)	/* notify completion */
52 #define    UNIPHIER_SSCOQM_CM_INV		0x0	/* invalidate */
53 #define    UNIPHIER_SSCOQM_CM_CLEAN		0x1	/* clean */
54 #define    UNIPHIER_SSCOQM_CM_FLUSH		0x2	/* flush */
55 #define UNIPHIER_SSCOQAD	0x24c	/* Cache Operation Queue Address */
56 #define UNIPHIER_SSCOQSZ	0x250	/* Cache Operation Queue Size */
57 #define UNIPHIER_SSCOPPQSEF	0x25c	/* Cache Operation Queue Set Complete*/
58 #define    UNIPHIER_SSCOPPQSEF_FE		BIT(1)
59 #define    UNIPHIER_SSCOPPQSEF_OE		BIT(0)
60 #define UNIPHIER_SSCOLPQS	0x260	/* Cache Operation Queue Status */
61 #define    UNIPHIER_SSCOLPQS_EF			BIT(2)
62 #define    UNIPHIER_SSCOLPQS_EST		BIT(1)
63 #define    UNIPHIER_SSCOLPQS_QST		BIT(0)
64 
65 /* Is the operation region specified by address range? */
66 #define UNIPHIER_SSCOQM_S_IS_RANGE(op) \
67 		((op & UNIPHIER_SSCOQM_S_MASK) == UNIPHIER_SSCOQM_S_RANGE)
68 
69 /**
70  * uniphier_cache_data - UniPhier outer cache specific data
71  *
72  * @ctrl_base: virtual base address of control registers
73  * @rev_base: virtual base address of revision registers
74  * @op_base: virtual base address of operation registers
75  * @way_mask: each bit specifies if the way is present
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_mask;
87 	u32 nsets;
88 	u32 line_size;
89 	u32 range_op_max_size;
90 	struct list_head list;
91 };
92 
93 /*
94  * List of the whole outer cache hierarchy.  This list is only modified during
95  * the early boot stage, so no mutex is taken for the access to the list.
96  */
97 static LIST_HEAD(uniphier_cache_list);
98 
99 /**
100  * __uniphier_cache_sync - perform a sync point for a particular cache level
101  *
102  * @data: cache controller specific data
103  */
104 static void __uniphier_cache_sync(struct uniphier_cache_data *data)
105 {
106 	/* This sequence need not be atomic.  Do not disable IRQ. */
107 	writel_relaxed(UNIPHIER_SSCOPE_CM_SYNC,
108 		       data->op_base + UNIPHIER_SSCOPE);
109 	/* need a read back to confirm */
110 	readl_relaxed(data->op_base + UNIPHIER_SSCOPE);
111 }
112 
113 /**
114  * __uniphier_cache_maint_common - run a queue operation for a particular level
115  *
116  * @data: cache controller specific data
117  * @start: start address of range operation (don't care for "all" operation)
118  * @size: data size of range operation (don't care for "all" operation)
119  * @operation: flags to specify the desired cache operation
120  */
121 static void __uniphier_cache_maint_common(struct uniphier_cache_data *data,
122 					  unsigned long start,
123 					  unsigned long size,
124 					  u32 operation)
125 {
126 	unsigned long flags;
127 
128 	/*
129 	 * No spin lock is necessary here because:
130 	 *
131 	 * [1] This outer cache controller is able to accept maintenance
132 	 * operations from multiple CPUs at a time in an SMP system; if a
133 	 * maintenance operation is under way and another operation is issued,
134 	 * the new one is stored in the queue.  The controller performs one
135 	 * operation after another.  If the queue is full, the status register,
136 	 * UNIPHIER_SSCOPPQSEF, indicates that the queue registration has
137 	 * failed.  The status registers, UNIPHIER_{SSCOPPQSEF, SSCOLPQS}, have
138 	 * different instances for each CPU, i.e. each CPU can track the status
139 	 * of the maintenance operations triggered by itself.
140 	 *
141 	 * [2] The cache command registers, UNIPHIER_{SSCOQM, SSCOQAD, SSCOQSZ,
142 	 * SSCOQWN}, are shared between multiple CPUs, but the hardware still
143 	 * guarantees the registration sequence is atomic; the write access to
144 	 * them are arbitrated by the hardware.  The first accessor to the
145 	 * register, UNIPHIER_SSCOQM, holds the access right and it is released
146 	 * by reading the status register, UNIPHIER_SSCOPPQSEF.  While one CPU
147 	 * is holding the access right, other CPUs fail to register operations.
148 	 * One CPU should not hold the access right for a long time, so local
149 	 * IRQs should be disabled while the following sequence.
150 	 */
151 	local_irq_save(flags);
152 
153 	/* clear the complete notification flag */
154 	writel_relaxed(UNIPHIER_SSCOLPQS_EF, data->op_base + UNIPHIER_SSCOLPQS);
155 
156 	do {
157 		/* set cache operation */
158 		writel_relaxed(UNIPHIER_SSCOQM_CE | operation,
159 			       data->op_base + UNIPHIER_SSCOQM);
160 
161 		/* set address range if needed */
162 		if (likely(UNIPHIER_SSCOQM_S_IS_RANGE(operation))) {
163 			writel_relaxed(start, data->op_base + UNIPHIER_SSCOQAD);
164 			writel_relaxed(size, data->op_base + UNIPHIER_SSCOQSZ);
165 		}
166 	} while (unlikely(readl_relaxed(data->op_base + UNIPHIER_SSCOPPQSEF) &
167 			  (UNIPHIER_SSCOPPQSEF_FE | UNIPHIER_SSCOPPQSEF_OE)));
168 
169 	/* wait until the operation is completed */
170 	while (likely(readl_relaxed(data->op_base + UNIPHIER_SSCOLPQS) !=
171 		      UNIPHIER_SSCOLPQS_EF))
172 		cpu_relax();
173 
174 	local_irq_restore(flags);
175 }
176 
177 static void __uniphier_cache_maint_all(struct uniphier_cache_data *data,
178 				       u32 operation)
179 {
180 	__uniphier_cache_maint_common(data, 0, 0,
181 				      UNIPHIER_SSCOQM_S_ALL | operation);
182 
183 	__uniphier_cache_sync(data);
184 }
185 
186 static void __uniphier_cache_maint_range(struct uniphier_cache_data *data,
187 					 unsigned long start, unsigned long end,
188 					 u32 operation)
189 {
190 	unsigned long size;
191 
192 	/*
193 	 * If the start address is not aligned,
194 	 * perform a cache operation for the first cache-line
195 	 */
196 	start = start & ~(data->line_size - 1);
197 
198 	size = end - start;
199 
200 	if (unlikely(size >= (unsigned long)(-data->line_size))) {
201 		/* this means cache operation for all range */
202 		__uniphier_cache_maint_all(data, operation);
203 		return;
204 	}
205 
206 	/*
207 	 * If the end address is not aligned,
208 	 * perform a cache operation for the last cache-line
209 	 */
210 	size = ALIGN(size, data->line_size);
211 
212 	while (size) {
213 		unsigned long chunk_size = min_t(unsigned long, size,
214 						 data->range_op_max_size);
215 
216 		__uniphier_cache_maint_common(data, start, chunk_size,
217 					UNIPHIER_SSCOQM_S_RANGE | operation);
218 
219 		start += chunk_size;
220 		size -= chunk_size;
221 	}
222 
223 	__uniphier_cache_sync(data);
224 }
225 
226 static void __uniphier_cache_enable(struct uniphier_cache_data *data, bool on)
227 {
228 	u32 val = 0;
229 
230 	if (on)
231 		val = UNIPHIER_SSCC_WTG | UNIPHIER_SSCC_PRD | UNIPHIER_SSCC_ON;
232 
233 	writel_relaxed(val, data->ctrl_base + UNIPHIER_SSCC);
234 }
235 
236 static void __init __uniphier_cache_set_active_ways(
237 					struct uniphier_cache_data *data)
238 {
239 	unsigned int cpu;
240 
241 	for_each_possible_cpu(cpu)
242 		writel_relaxed(data->way_mask, data->way_ctrl_base + 4 * cpu);
243 }
244 
245 static void uniphier_cache_maint_range(unsigned long start, unsigned long end,
246 				       u32 operation)
247 {
248 	struct uniphier_cache_data *data;
249 
250 	list_for_each_entry(data, &uniphier_cache_list, list)
251 		__uniphier_cache_maint_range(data, start, end, operation);
252 }
253 
254 static void uniphier_cache_maint_all(u32 operation)
255 {
256 	struct uniphier_cache_data *data;
257 
258 	list_for_each_entry(data, &uniphier_cache_list, list)
259 		__uniphier_cache_maint_all(data, operation);
260 }
261 
262 static void uniphier_cache_inv_range(unsigned long start, unsigned long end)
263 {
264 	uniphier_cache_maint_range(start, end, UNIPHIER_SSCOQM_CM_INV);
265 }
266 
267 static void uniphier_cache_clean_range(unsigned long start, unsigned long end)
268 {
269 	uniphier_cache_maint_range(start, end, UNIPHIER_SSCOQM_CM_CLEAN);
270 }
271 
272 static void uniphier_cache_flush_range(unsigned long start, unsigned long end)
273 {
274 	uniphier_cache_maint_range(start, end, UNIPHIER_SSCOQM_CM_FLUSH);
275 }
276 
277 static void __init uniphier_cache_inv_all(void)
278 {
279 	uniphier_cache_maint_all(UNIPHIER_SSCOQM_CM_INV);
280 }
281 
282 static void uniphier_cache_flush_all(void)
283 {
284 	uniphier_cache_maint_all(UNIPHIER_SSCOQM_CM_FLUSH);
285 }
286 
287 static void uniphier_cache_disable(void)
288 {
289 	struct uniphier_cache_data *data;
290 
291 	list_for_each_entry_reverse(data, &uniphier_cache_list, list)
292 		__uniphier_cache_enable(data, false);
293 
294 	uniphier_cache_flush_all();
295 }
296 
297 static void __init uniphier_cache_enable(void)
298 {
299 	struct uniphier_cache_data *data;
300 
301 	uniphier_cache_inv_all();
302 
303 	list_for_each_entry(data, &uniphier_cache_list, list) {
304 		__uniphier_cache_enable(data, true);
305 		__uniphier_cache_set_active_ways(data);
306 	}
307 }
308 
309 static void uniphier_cache_sync(void)
310 {
311 	struct uniphier_cache_data *data;
312 
313 	list_for_each_entry(data, &uniphier_cache_list, list)
314 		__uniphier_cache_sync(data);
315 }
316 
317 static const struct of_device_id uniphier_cache_match[] __initconst = {
318 	{ .compatible = "socionext,uniphier-system-cache" },
319 	{ /* sentinel */ }
320 };
321 
322 static int __init __uniphier_cache_init(struct device_node *np,
323 					unsigned int *cache_level)
324 {
325 	struct uniphier_cache_data *data;
326 	u32 level, cache_size;
327 	struct device_node *next_np;
328 	int ret = 0;
329 
330 	if (!of_match_node(uniphier_cache_match, np)) {
331 		pr_err("L%d: not compatible with uniphier cache\n",
332 		       *cache_level);
333 		return -EINVAL;
334 	}
335 
336 	if (of_property_read_u32(np, "cache-level", &level)) {
337 		pr_err("L%d: cache-level is not specified\n", *cache_level);
338 		return -EINVAL;
339 	}
340 
341 	if (level != *cache_level) {
342 		pr_err("L%d: cache-level is unexpected value %d\n",
343 		       *cache_level, level);
344 		return -EINVAL;
345 	}
346 
347 	if (!of_property_read_bool(np, "cache-unified")) {
348 		pr_err("L%d: cache-unified is not specified\n", *cache_level);
349 		return -EINVAL;
350 	}
351 
352 	data = kzalloc(sizeof(*data), GFP_KERNEL);
353 	if (!data)
354 		return -ENOMEM;
355 
356 	if (of_property_read_u32(np, "cache-line-size", &data->line_size) ||
357 	    !is_power_of_2(data->line_size)) {
358 		pr_err("L%d: cache-line-size is unspecified or invalid\n",
359 		       *cache_level);
360 		ret = -EINVAL;
361 		goto err;
362 	}
363 
364 	if (of_property_read_u32(np, "cache-sets", &data->nsets) ||
365 	    !is_power_of_2(data->nsets)) {
366 		pr_err("L%d: cache-sets is unspecified or invalid\n",
367 		       *cache_level);
368 		ret = -EINVAL;
369 		goto err;
370 	}
371 
372 	if (of_property_read_u32(np, "cache-size", &cache_size) ||
373 	    cache_size == 0 || cache_size % (data->nsets * data->line_size)) {
374 		pr_err("L%d: cache-size is unspecified or invalid\n",
375 		       *cache_level);
376 		ret = -EINVAL;
377 		goto err;
378 	}
379 
380 	data->way_mask = GENMASK(cache_size / data->nsets / data->line_size - 1,
381 				 0);
382 
383 	data->ctrl_base = of_iomap(np, 0);
384 	if (!data->ctrl_base) {
385 		pr_err("L%d: failed to map control register\n", *cache_level);
386 		ret = -ENOMEM;
387 		goto err;
388 	}
389 
390 	data->rev_base = of_iomap(np, 1);
391 	if (!data->rev_base) {
392 		pr_err("L%d: failed to map revision register\n", *cache_level);
393 		ret = -ENOMEM;
394 		goto err;
395 	}
396 
397 	data->op_base = of_iomap(np, 2);
398 	if (!data->op_base) {
399 		pr_err("L%d: failed to map operation register\n", *cache_level);
400 		ret = -ENOMEM;
401 		goto err;
402 	}
403 
404 	data->way_ctrl_base = data->ctrl_base + 0xc00;
405 
406 	if (*cache_level == 2) {
407 		u32 revision = readl(data->rev_base + UNIPHIER_SSCID);
408 		/*
409 		 * The size of range operation is limited to (1 << 22) or less
410 		 * for PH-sLD8 or older SoCs.
411 		 */
412 		if (revision <= 0x16)
413 			data->range_op_max_size = (u32)1 << 22;
414 
415 		/*
416 		 * Unfortunatly, the offset address of active way control base
417 		 * varies from SoC to SoC.
418 		 */
419 		switch (revision) {
420 		case 0x11:	/* sLD3 */
421 			data->way_ctrl_base = data->ctrl_base + 0x870;
422 			break;
423 		case 0x12:	/* LD4 */
424 		case 0x16:	/* sld8 */
425 			data->way_ctrl_base = data->ctrl_base + 0x840;
426 			break;
427 		default:
428 			break;
429 		}
430 	}
431 
432 	data->range_op_max_size -= data->line_size;
433 
434 	INIT_LIST_HEAD(&data->list);
435 	list_add_tail(&data->list, &uniphier_cache_list); /* no mutex */
436 
437 	/*
438 	 * OK, this level has been successfully initialized.  Look for the next
439 	 * level cache.  Do not roll back even if the initialization of the
440 	 * next level cache fails because we want to continue with available
441 	 * cache levels.
442 	 */
443 	next_np = of_find_next_cache_node(np);
444 	if (next_np) {
445 		(*cache_level)++;
446 		ret = __uniphier_cache_init(next_np, cache_level);
447 	}
448 	of_node_put(next_np);
449 
450 	return ret;
451 err:
452 	iounmap(data->op_base);
453 	iounmap(data->rev_base);
454 	iounmap(data->ctrl_base);
455 	kfree(data);
456 
457 	return ret;
458 }
459 
460 int __init uniphier_cache_init(void)
461 {
462 	struct device_node *np = NULL;
463 	unsigned int cache_level;
464 	int ret = 0;
465 
466 	/* look for level 2 cache */
467 	while ((np = of_find_matching_node(np, uniphier_cache_match)))
468 		if (!of_property_read_u32(np, "cache-level", &cache_level) &&
469 		    cache_level == 2)
470 			break;
471 
472 	if (!np)
473 		return -ENODEV;
474 
475 	ret = __uniphier_cache_init(np, &cache_level);
476 	of_node_put(np);
477 
478 	if (ret) {
479 		/*
480 		 * Error out iif L2 initialization fails.  Continue with any
481 		 * error on L3 or outer because they are optional.
482 		 */
483 		if (cache_level == 2) {
484 			pr_err("failed to initialize L2 cache\n");
485 			return ret;
486 		}
487 
488 		cache_level--;
489 		ret = 0;
490 	}
491 
492 	outer_cache.inv_range = uniphier_cache_inv_range;
493 	outer_cache.clean_range = uniphier_cache_clean_range;
494 	outer_cache.flush_range = uniphier_cache_flush_range;
495 	outer_cache.flush_all = uniphier_cache_flush_all;
496 	outer_cache.disable = uniphier_cache_disable;
497 	outer_cache.sync = uniphier_cache_sync;
498 
499 	uniphier_cache_enable();
500 
501 	pr_info("enabled outer cache (cache level: %d)\n", cache_level);
502 
503 	return ret;
504 }
505