1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * cbe_regs.c
4  *
5  * Accessor routines for the various MMIO register blocks of the CBE
6  *
7  * (c) 2006 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
8  */
9 
10 #include <linux/percpu.h>
11 #include <linux/types.h>
12 #include <linux/export.h>
13 #include <linux/of.h>
14 #include <linux/of_address.h>
15 #include <linux/pgtable.h>
16 
17 #include <asm/io.h>
18 #include <asm/ptrace.h>
19 #include <asm/cell-regs.h>
20 
21 /*
22  * Current implementation uses "cpu" nodes. We build our own mapping
23  * array of cpu numbers to cpu nodes locally for now to allow interrupt
24  * time code to have a fast path rather than call of_get_cpu_node(). If
25  * we implement cpu hotplug, we'll have to install an appropriate notifier
26  * in order to release references to the cpu going away
27  */
28 static struct cbe_regs_map
29 {
30 	struct device_node *cpu_node;
31 	struct device_node *be_node;
32 	struct cbe_pmd_regs __iomem *pmd_regs;
33 	struct cbe_iic_regs __iomem *iic_regs;
34 	struct cbe_mic_tm_regs __iomem *mic_tm_regs;
35 	struct cbe_pmd_shadow_regs pmd_shadow_regs;
36 } cbe_regs_maps[MAX_CBE];
37 static int cbe_regs_map_count;
38 
39 static struct cbe_thread_map
40 {
41 	struct device_node *cpu_node;
42 	struct device_node *be_node;
43 	struct cbe_regs_map *regs;
44 	unsigned int thread_id;
45 	unsigned int cbe_id;
46 } cbe_thread_map[NR_CPUS];
47 
48 static cpumask_t cbe_local_mask[MAX_CBE] = { [0 ... MAX_CBE-1] = {CPU_BITS_NONE} };
49 static cpumask_t cbe_first_online_cpu = { CPU_BITS_NONE };
50 
51 static struct cbe_regs_map *cbe_find_map(struct device_node *np)
52 {
53 	int i;
54 	struct device_node *tmp_np;
55 
56 	if (!of_node_is_type(np, "spe")) {
57 		for (i = 0; i < cbe_regs_map_count; i++)
58 			if (cbe_regs_maps[i].cpu_node == np ||
59 			    cbe_regs_maps[i].be_node == np)
60 				return &cbe_regs_maps[i];
61 		return NULL;
62 	}
63 
64 	if (np->data)
65 		return np->data;
66 
67 	/* walk up path until cpu or be node was found */
68 	tmp_np = np;
69 	do {
70 		tmp_np = tmp_np->parent;
71 		/* on a correct devicetree we wont get up to root */
72 		BUG_ON(!tmp_np);
73 	} while (!of_node_is_type(tmp_np, "cpu") ||
74 		 !of_node_is_type(tmp_np, "be"));
75 
76 	np->data = cbe_find_map(tmp_np);
77 
78 	return np->data;
79 }
80 
81 struct cbe_pmd_regs __iomem *cbe_get_pmd_regs(struct device_node *np)
82 {
83 	struct cbe_regs_map *map = cbe_find_map(np);
84 	if (map == NULL)
85 		return NULL;
86 	return map->pmd_regs;
87 }
88 EXPORT_SYMBOL_GPL(cbe_get_pmd_regs);
89 
90 struct cbe_pmd_regs __iomem *cbe_get_cpu_pmd_regs(int cpu)
91 {
92 	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
93 	if (map == NULL)
94 		return NULL;
95 	return map->pmd_regs;
96 }
97 EXPORT_SYMBOL_GPL(cbe_get_cpu_pmd_regs);
98 
99 struct cbe_pmd_shadow_regs *cbe_get_pmd_shadow_regs(struct device_node *np)
100 {
101 	struct cbe_regs_map *map = cbe_find_map(np);
102 	if (map == NULL)
103 		return NULL;
104 	return &map->pmd_shadow_regs;
105 }
106 
107 struct cbe_pmd_shadow_regs *cbe_get_cpu_pmd_shadow_regs(int cpu)
108 {
109 	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
110 	if (map == NULL)
111 		return NULL;
112 	return &map->pmd_shadow_regs;
113 }
114 
115 struct cbe_iic_regs __iomem *cbe_get_iic_regs(struct device_node *np)
116 {
117 	struct cbe_regs_map *map = cbe_find_map(np);
118 	if (map == NULL)
119 		return NULL;
120 	return map->iic_regs;
121 }
122 
123 struct cbe_iic_regs __iomem *cbe_get_cpu_iic_regs(int cpu)
124 {
125 	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
126 	if (map == NULL)
127 		return NULL;
128 	return map->iic_regs;
129 }
130 
131 struct cbe_mic_tm_regs __iomem *cbe_get_mic_tm_regs(struct device_node *np)
132 {
133 	struct cbe_regs_map *map = cbe_find_map(np);
134 	if (map == NULL)
135 		return NULL;
136 	return map->mic_tm_regs;
137 }
138 
139 struct cbe_mic_tm_regs __iomem *cbe_get_cpu_mic_tm_regs(int cpu)
140 {
141 	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
142 	if (map == NULL)
143 		return NULL;
144 	return map->mic_tm_regs;
145 }
146 EXPORT_SYMBOL_GPL(cbe_get_cpu_mic_tm_regs);
147 
148 u32 cbe_get_hw_thread_id(int cpu)
149 {
150 	return cbe_thread_map[cpu].thread_id;
151 }
152 EXPORT_SYMBOL_GPL(cbe_get_hw_thread_id);
153 
154 u32 cbe_cpu_to_node(int cpu)
155 {
156 	return cbe_thread_map[cpu].cbe_id;
157 }
158 EXPORT_SYMBOL_GPL(cbe_cpu_to_node);
159 
160 u32 cbe_node_to_cpu(int node)
161 {
162 	return cpumask_first(&cbe_local_mask[node]);
163 
164 }
165 EXPORT_SYMBOL_GPL(cbe_node_to_cpu);
166 
167 static struct device_node *__init cbe_get_be_node(int cpu_id)
168 {
169 	struct device_node *np;
170 
171 	for_each_node_by_type (np, "be") {
172 		int len,i;
173 		const phandle *cpu_handle;
174 
175 		cpu_handle = of_get_property(np, "cpus", &len);
176 
177 		/*
178 		 * the CAB SLOF tree is non compliant, so we just assume
179 		 * there is only one node
180 		 */
181 		if (WARN_ON_ONCE(!cpu_handle))
182 			return np;
183 
184 		for (i = 0; i < len; i++) {
185 			struct device_node *ch_np = of_find_node_by_phandle(cpu_handle[i]);
186 			struct device_node *ci_np = of_get_cpu_node(cpu_id, NULL);
187 
188 			of_node_put(ch_np);
189 			of_node_put(ci_np);
190 
191 			if (ch_np == ci_np)
192 				return np;
193 		}
194 	}
195 
196 	return NULL;
197 }
198 
199 static void __init cbe_fill_regs_map(struct cbe_regs_map *map)
200 {
201 	if(map->be_node) {
202 		struct device_node *be, *np, *parent_np;
203 
204 		be = map->be_node;
205 
206 		for_each_node_by_type(np, "pervasive") {
207 			parent_np = of_get_parent(np);
208 			if (parent_np == be)
209 				map->pmd_regs = of_iomap(np, 0);
210 			of_node_put(parent_np);
211 		}
212 
213 		for_each_node_by_type(np, "CBEA-Internal-Interrupt-Controller") {
214 			parent_np = of_get_parent(np);
215 			if (parent_np == be)
216 				map->iic_regs = of_iomap(np, 2);
217 			of_node_put(parent_np);
218 		}
219 
220 		for_each_node_by_type(np, "mic-tm") {
221 			parent_np = of_get_parent(np);
222 			if (parent_np == be)
223 				map->mic_tm_regs = of_iomap(np, 0);
224 			of_node_put(parent_np);
225 		}
226 	} else {
227 		struct device_node *cpu;
228 		/* That hack must die die die ! */
229 		const struct address_prop {
230 			unsigned long address;
231 			unsigned int len;
232 		} __attribute__((packed)) *prop;
233 
234 		cpu = map->cpu_node;
235 
236 		prop = of_get_property(cpu, "pervasive", NULL);
237 		if (prop != NULL)
238 			map->pmd_regs = ioremap(prop->address, prop->len);
239 
240 		prop = of_get_property(cpu, "iic", NULL);
241 		if (prop != NULL)
242 			map->iic_regs = ioremap(prop->address, prop->len);
243 
244 		prop = of_get_property(cpu, "mic-tm", NULL);
245 		if (prop != NULL)
246 			map->mic_tm_regs = ioremap(prop->address, prop->len);
247 	}
248 }
249 
250 
251 void __init cbe_regs_init(void)
252 {
253 	int i;
254 	unsigned int thread_id;
255 	struct device_node *cpu;
256 
257 	/* Build local fast map of CPUs */
258 	for_each_possible_cpu(i) {
259 		cbe_thread_map[i].cpu_node = of_get_cpu_node(i, &thread_id);
260 		cbe_thread_map[i].be_node = cbe_get_be_node(i);
261 		cbe_thread_map[i].thread_id = thread_id;
262 	}
263 
264 	/* Find maps for each device tree CPU */
265 	for_each_node_by_type(cpu, "cpu") {
266 		struct cbe_regs_map *map;
267 		unsigned int cbe_id;
268 
269 		cbe_id = cbe_regs_map_count++;
270 		map = &cbe_regs_maps[cbe_id];
271 
272 		if (cbe_regs_map_count > MAX_CBE) {
273 			printk(KERN_ERR "cbe_regs: More BE chips than supported"
274 			       "!\n");
275 			cbe_regs_map_count--;
276 			of_node_put(cpu);
277 			return;
278 		}
279 		of_node_put(map->cpu_node);
280 		map->cpu_node = of_node_get(cpu);
281 
282 		for_each_possible_cpu(i) {
283 			struct cbe_thread_map *thread = &cbe_thread_map[i];
284 
285 			if (thread->cpu_node == cpu) {
286 				thread->regs = map;
287 				thread->cbe_id = cbe_id;
288 				map->be_node = thread->be_node;
289 				cpumask_set_cpu(i, &cbe_local_mask[cbe_id]);
290 				if(thread->thread_id == 0)
291 					cpumask_set_cpu(i, &cbe_first_online_cpu);
292 			}
293 		}
294 
295 		cbe_fill_regs_map(map);
296 	}
297 }
298 
299