xref: /linux/drivers/cache/sifive_ccache.c (revision eed4edda910fe34dfae8c6bfbcf57f4593a54295)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * SiFive composable cache controller Driver
4  *
5  * Copyright (C) 2018-2022 SiFive, Inc.
6  *
7  */
8 
9 #define pr_fmt(fmt) "CCACHE: " fmt
10 
11 #include <linux/align.h>
12 #include <linux/debugfs.h>
13 #include <linux/interrupt.h>
14 #include <linux/of_irq.h>
15 #include <linux/of_address.h>
16 #include <linux/device.h>
17 #include <linux/bitfield.h>
18 #include <asm/cacheflush.h>
19 #include <asm/cacheinfo.h>
20 #include <asm/dma-noncoherent.h>
21 #include <soc/sifive/sifive_ccache.h>
22 
23 #define SIFIVE_CCACHE_DIRECCFIX_LOW 0x100
24 #define SIFIVE_CCACHE_DIRECCFIX_HIGH 0x104
25 #define SIFIVE_CCACHE_DIRECCFIX_COUNT 0x108
26 
27 #define SIFIVE_CCACHE_DIRECCFAIL_LOW 0x120
28 #define SIFIVE_CCACHE_DIRECCFAIL_HIGH 0x124
29 #define SIFIVE_CCACHE_DIRECCFAIL_COUNT 0x128
30 
31 #define SIFIVE_CCACHE_DATECCFIX_LOW 0x140
32 #define SIFIVE_CCACHE_DATECCFIX_HIGH 0x144
33 #define SIFIVE_CCACHE_DATECCFIX_COUNT 0x148
34 
35 #define SIFIVE_CCACHE_DATECCFAIL_LOW 0x160
36 #define SIFIVE_CCACHE_DATECCFAIL_HIGH 0x164
37 #define SIFIVE_CCACHE_DATECCFAIL_COUNT 0x168
38 
39 #define SIFIVE_CCACHE_CONFIG 0x00
40 #define SIFIVE_CCACHE_CONFIG_BANK_MASK GENMASK_ULL(7, 0)
41 #define SIFIVE_CCACHE_CONFIG_WAYS_MASK GENMASK_ULL(15, 8)
42 #define SIFIVE_CCACHE_CONFIG_SETS_MASK GENMASK_ULL(23, 16)
43 #define SIFIVE_CCACHE_CONFIG_BLKS_MASK GENMASK_ULL(31, 24)
44 
45 #define SIFIVE_CCACHE_FLUSH64 0x200
46 #define SIFIVE_CCACHE_FLUSH32 0x240
47 
48 #define SIFIVE_CCACHE_WAYENABLE 0x08
49 #define SIFIVE_CCACHE_ECCINJECTERR 0x40
50 
51 #define SIFIVE_CCACHE_MAX_ECCINTR 4
52 #define SIFIVE_CCACHE_LINE_SIZE 64
53 
54 static void __iomem *ccache_base;
55 static int g_irq[SIFIVE_CCACHE_MAX_ECCINTR];
56 static struct riscv_cacheinfo_ops ccache_cache_ops;
57 static int level;
58 
59 enum {
60 	DIR_CORR = 0,
61 	DATA_CORR,
62 	DATA_UNCORR,
63 	DIR_UNCORR,
64 };
65 
66 enum {
67 	QUIRK_NONSTANDARD_CACHE_OPS	= BIT(0),
68 	QUIRK_BROKEN_DATA_UNCORR	= BIT(1),
69 };
70 
71 #ifdef CONFIG_DEBUG_FS
72 static struct dentry *sifive_test;
73 
74 static ssize_t ccache_write(struct file *file, const char __user *data,
75 			    size_t count, loff_t *ppos)
76 {
77 	unsigned int val;
78 
79 	if (kstrtouint_from_user(data, count, 0, &val))
80 		return -EINVAL;
81 	if ((val < 0xFF) || (val >= 0x10000 && val < 0x100FF))
82 		writel(val, ccache_base + SIFIVE_CCACHE_ECCINJECTERR);
83 	else
84 		return -EINVAL;
85 	return count;
86 }
87 
88 static const struct file_operations ccache_fops = {
89 	.owner = THIS_MODULE,
90 	.open = simple_open,
91 	.write = ccache_write
92 };
93 
94 static void setup_sifive_debug(void)
95 {
96 	sifive_test = debugfs_create_dir("sifive_ccache_cache", NULL);
97 
98 	debugfs_create_file("sifive_debug_inject_error", 0200,
99 			    sifive_test, NULL, &ccache_fops);
100 }
101 #endif
102 
103 static void ccache_config_read(void)
104 {
105 	u32 cfg;
106 
107 	cfg = readl(ccache_base + SIFIVE_CCACHE_CONFIG);
108 	pr_info("%llu banks, %llu ways, sets/bank=%llu, bytes/block=%llu\n",
109 		FIELD_GET(SIFIVE_CCACHE_CONFIG_BANK_MASK, cfg),
110 		FIELD_GET(SIFIVE_CCACHE_CONFIG_WAYS_MASK, cfg),
111 		BIT_ULL(FIELD_GET(SIFIVE_CCACHE_CONFIG_SETS_MASK, cfg)),
112 		BIT_ULL(FIELD_GET(SIFIVE_CCACHE_CONFIG_BLKS_MASK, cfg)));
113 
114 	cfg = readl(ccache_base + SIFIVE_CCACHE_WAYENABLE);
115 	pr_info("Index of the largest way enabled: %u\n", cfg);
116 }
117 
118 static const struct of_device_id sifive_ccache_ids[] = {
119 	{ .compatible = "sifive,fu540-c000-ccache" },
120 	{ .compatible = "sifive,fu740-c000-ccache" },
121 	{ .compatible = "starfive,jh7100-ccache",
122 	  .data = (void *)(QUIRK_NONSTANDARD_CACHE_OPS | QUIRK_BROKEN_DATA_UNCORR) },
123 	{ .compatible = "sifive,ccache0" },
124 	{ /* end of table */ }
125 };
126 
127 static ATOMIC_NOTIFIER_HEAD(ccache_err_chain);
128 
129 int register_sifive_ccache_error_notifier(struct notifier_block *nb)
130 {
131 	return atomic_notifier_chain_register(&ccache_err_chain, nb);
132 }
133 EXPORT_SYMBOL_GPL(register_sifive_ccache_error_notifier);
134 
135 int unregister_sifive_ccache_error_notifier(struct notifier_block *nb)
136 {
137 	return atomic_notifier_chain_unregister(&ccache_err_chain, nb);
138 }
139 EXPORT_SYMBOL_GPL(unregister_sifive_ccache_error_notifier);
140 
141 #ifdef CONFIG_RISCV_NONSTANDARD_CACHE_OPS
142 static void ccache_flush_range(phys_addr_t start, size_t len)
143 {
144 	phys_addr_t end = start + len;
145 	phys_addr_t line;
146 
147 	if (!len)
148 		return;
149 
150 	mb();
151 	for (line = ALIGN_DOWN(start, SIFIVE_CCACHE_LINE_SIZE); line < end;
152 			line += SIFIVE_CCACHE_LINE_SIZE) {
153 #ifdef CONFIG_32BIT
154 		writel(line >> 4, ccache_base + SIFIVE_CCACHE_FLUSH32);
155 #else
156 		writeq(line, ccache_base + SIFIVE_CCACHE_FLUSH64);
157 #endif
158 		mb();
159 	}
160 }
161 
162 static const struct riscv_nonstd_cache_ops ccache_mgmt_ops __initconst = {
163 	.wback = &ccache_flush_range,
164 	.inv = &ccache_flush_range,
165 	.wback_inv = &ccache_flush_range,
166 };
167 #endif /* CONFIG_RISCV_NONSTANDARD_CACHE_OPS */
168 
169 static int ccache_largest_wayenabled(void)
170 {
171 	return readl(ccache_base + SIFIVE_CCACHE_WAYENABLE) & 0xFF;
172 }
173 
174 static ssize_t number_of_ways_enabled_show(struct device *dev,
175 					   struct device_attribute *attr,
176 					   char *buf)
177 {
178 	return sprintf(buf, "%u\n", ccache_largest_wayenabled());
179 }
180 
181 static DEVICE_ATTR_RO(number_of_ways_enabled);
182 
183 static struct attribute *priv_attrs[] = {
184 	&dev_attr_number_of_ways_enabled.attr,
185 	NULL,
186 };
187 
188 static const struct attribute_group priv_attr_group = {
189 	.attrs = priv_attrs,
190 };
191 
192 static const struct attribute_group *ccache_get_priv_group(struct cacheinfo
193 							   *this_leaf)
194 {
195 	/* We want to use private group for composable cache only */
196 	if (this_leaf->level == level)
197 		return &priv_attr_group;
198 	else
199 		return NULL;
200 }
201 
202 static irqreturn_t ccache_int_handler(int irq, void *device)
203 {
204 	unsigned int add_h, add_l;
205 
206 	if (irq == g_irq[DIR_CORR]) {
207 		add_h = readl(ccache_base + SIFIVE_CCACHE_DIRECCFIX_HIGH);
208 		add_l = readl(ccache_base + SIFIVE_CCACHE_DIRECCFIX_LOW);
209 		pr_err("DirError @ 0x%08X.%08X\n", add_h, add_l);
210 		/* Reading this register clears the DirError interrupt sig */
211 		readl(ccache_base + SIFIVE_CCACHE_DIRECCFIX_COUNT);
212 		atomic_notifier_call_chain(&ccache_err_chain,
213 					   SIFIVE_CCACHE_ERR_TYPE_CE,
214 					   "DirECCFix");
215 	}
216 	if (irq == g_irq[DIR_UNCORR]) {
217 		add_h = readl(ccache_base + SIFIVE_CCACHE_DIRECCFAIL_HIGH);
218 		add_l = readl(ccache_base + SIFIVE_CCACHE_DIRECCFAIL_LOW);
219 		/* Reading this register clears the DirFail interrupt sig */
220 		readl(ccache_base + SIFIVE_CCACHE_DIRECCFAIL_COUNT);
221 		atomic_notifier_call_chain(&ccache_err_chain,
222 					   SIFIVE_CCACHE_ERR_TYPE_UE,
223 					   "DirECCFail");
224 		panic("CCACHE: DirFail @ 0x%08X.%08X\n", add_h, add_l);
225 	}
226 	if (irq == g_irq[DATA_CORR]) {
227 		add_h = readl(ccache_base + SIFIVE_CCACHE_DATECCFIX_HIGH);
228 		add_l = readl(ccache_base + SIFIVE_CCACHE_DATECCFIX_LOW);
229 		pr_err("DataError @ 0x%08X.%08X\n", add_h, add_l);
230 		/* Reading this register clears the DataError interrupt sig */
231 		readl(ccache_base + SIFIVE_CCACHE_DATECCFIX_COUNT);
232 		atomic_notifier_call_chain(&ccache_err_chain,
233 					   SIFIVE_CCACHE_ERR_TYPE_CE,
234 					   "DatECCFix");
235 	}
236 	if (irq == g_irq[DATA_UNCORR]) {
237 		add_h = readl(ccache_base + SIFIVE_CCACHE_DATECCFAIL_HIGH);
238 		add_l = readl(ccache_base + SIFIVE_CCACHE_DATECCFAIL_LOW);
239 		pr_err("DataFail @ 0x%08X.%08X\n", add_h, add_l);
240 		/* Reading this register clears the DataFail interrupt sig */
241 		readl(ccache_base + SIFIVE_CCACHE_DATECCFAIL_COUNT);
242 		atomic_notifier_call_chain(&ccache_err_chain,
243 					   SIFIVE_CCACHE_ERR_TYPE_UE,
244 					   "DatECCFail");
245 	}
246 
247 	return IRQ_HANDLED;
248 }
249 
250 static int __init sifive_ccache_init(void)
251 {
252 	struct device_node *np;
253 	struct resource res;
254 	int i, rc, intr_num;
255 	const struct of_device_id *match;
256 	unsigned long quirks;
257 
258 	np = of_find_matching_node_and_match(NULL, sifive_ccache_ids, &match);
259 	if (!np)
260 		return -ENODEV;
261 
262 	quirks = (uintptr_t)match->data;
263 
264 	if (of_address_to_resource(np, 0, &res)) {
265 		rc = -ENODEV;
266 		goto err_node_put;
267 	}
268 
269 	ccache_base = ioremap(res.start, resource_size(&res));
270 	if (!ccache_base) {
271 		rc = -ENOMEM;
272 		goto err_node_put;
273 	}
274 
275 	if (of_property_read_u32(np, "cache-level", &level)) {
276 		rc = -ENOENT;
277 		goto err_unmap;
278 	}
279 
280 	intr_num = of_property_count_u32_elems(np, "interrupts");
281 	if (!intr_num) {
282 		pr_err("No interrupts property\n");
283 		rc = -ENODEV;
284 		goto err_unmap;
285 	}
286 
287 	for (i = 0; i < intr_num; i++) {
288 		g_irq[i] = irq_of_parse_and_map(np, i);
289 
290 		if (i == DATA_UNCORR && (quirks & QUIRK_BROKEN_DATA_UNCORR))
291 			continue;
292 
293 		rc = request_irq(g_irq[i], ccache_int_handler, 0, "ccache_ecc",
294 				 NULL);
295 		if (rc) {
296 			pr_err("Could not request IRQ %d\n", g_irq[i]);
297 			goto err_free_irq;
298 		}
299 	}
300 	of_node_put(np);
301 
302 #ifdef CONFIG_RISCV_NONSTANDARD_CACHE_OPS
303 	if (quirks & QUIRK_NONSTANDARD_CACHE_OPS) {
304 		riscv_cbom_block_size = SIFIVE_CCACHE_LINE_SIZE;
305 		riscv_noncoherent_supported();
306 		riscv_noncoherent_register_cache_ops(&ccache_mgmt_ops);
307 	}
308 #endif
309 
310 	ccache_config_read();
311 
312 	ccache_cache_ops.get_priv_group = ccache_get_priv_group;
313 	riscv_set_cacheinfo_ops(&ccache_cache_ops);
314 
315 #ifdef CONFIG_DEBUG_FS
316 	setup_sifive_debug();
317 #endif
318 	return 0;
319 
320 err_free_irq:
321 	while (--i >= 0)
322 		free_irq(g_irq[i], NULL);
323 err_unmap:
324 	iounmap(ccache_base);
325 err_node_put:
326 	of_node_put(np);
327 	return rc;
328 }
329 
330 arch_initcall(sifive_ccache_init);
331