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_address.h>
14 #include <linux/of_device.h>
15 #include <linux/of_platform.h>
16 #include <linux/pgtable.h>
17 
18 #include <asm/io.h>
19 #include <asm/ptrace.h>
20 #include <asm/cell-regs.h>
21 
22 /*
23  * Current implementation uses "cpu" nodes. We build our own mapping
24  * array of cpu numbers to cpu nodes locally for now to allow interrupt
25  * time code to have a fast path rather than call of_get_cpu_node(). If
26  * we implement cpu hotplug, we'll have to install an appropriate notifier
27  * in order to release references to the cpu going away
28  */
29 static struct cbe_regs_map
30 {
31 	struct device_node *cpu_node;
32 	struct device_node *be_node;
33 	struct cbe_pmd_regs __iomem *pmd_regs;
34 	struct cbe_iic_regs __iomem *iic_regs;
35 	struct cbe_mic_tm_regs __iomem *mic_tm_regs;
36 	struct cbe_pmd_shadow_regs pmd_shadow_regs;
37 } cbe_regs_maps[MAX_CBE];
38 static int cbe_regs_map_count;
39 
40 static struct cbe_thread_map
41 {
42 	struct device_node *cpu_node;
43 	struct device_node *be_node;
44 	struct cbe_regs_map *regs;
45 	unsigned int thread_id;
46 	unsigned int cbe_id;
47 } cbe_thread_map[NR_CPUS];
48 
49 static cpumask_t cbe_local_mask[MAX_CBE] = { [0 ... MAX_CBE-1] = {CPU_BITS_NONE} };
50 static cpumask_t cbe_first_online_cpu = { CPU_BITS_NONE };
51 
cbe_find_map(struct device_node * np)52 static struct cbe_regs_map *cbe_find_map(struct device_node *np)
53 {
54 	int i;
55 	struct device_node *tmp_np;
56 
57 	if (!of_node_is_type(np, "spe")) {
58 		for (i = 0; i < cbe_regs_map_count; i++)
59 			if (cbe_regs_maps[i].cpu_node == np ||
60 			    cbe_regs_maps[i].be_node == np)
61 				return &cbe_regs_maps[i];
62 		return NULL;
63 	}
64 
65 	if (np->data)
66 		return np->data;
67 
68 	/* walk up path until cpu or be node was found */
69 	tmp_np = np;
70 	do {
71 		tmp_np = tmp_np->parent;
72 		/* on a correct devicetree we wont get up to root */
73 		BUG_ON(!tmp_np);
74 	} while (!of_node_is_type(tmp_np, "cpu") ||
75 		 !of_node_is_type(tmp_np, "be"));
76 
77 	np->data = cbe_find_map(tmp_np);
78 
79 	return np->data;
80 }
81 
cbe_get_pmd_regs(struct device_node * np)82 struct cbe_pmd_regs __iomem *cbe_get_pmd_regs(struct device_node *np)
83 {
84 	struct cbe_regs_map *map = cbe_find_map(np);
85 	if (map == NULL)
86 		return NULL;
87 	return map->pmd_regs;
88 }
89 EXPORT_SYMBOL_GPL(cbe_get_pmd_regs);
90 
cbe_get_cpu_pmd_regs(int cpu)91 struct cbe_pmd_regs __iomem *cbe_get_cpu_pmd_regs(int cpu)
92 {
93 	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
94 	if (map == NULL)
95 		return NULL;
96 	return map->pmd_regs;
97 }
98 EXPORT_SYMBOL_GPL(cbe_get_cpu_pmd_regs);
99 
cbe_get_pmd_shadow_regs(struct device_node * np)100 struct cbe_pmd_shadow_regs *cbe_get_pmd_shadow_regs(struct device_node *np)
101 {
102 	struct cbe_regs_map *map = cbe_find_map(np);
103 	if (map == NULL)
104 		return NULL;
105 	return &map->pmd_shadow_regs;
106 }
107 
cbe_get_cpu_pmd_shadow_regs(int cpu)108 struct cbe_pmd_shadow_regs *cbe_get_cpu_pmd_shadow_regs(int cpu)
109 {
110 	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
111 	if (map == NULL)
112 		return NULL;
113 	return &map->pmd_shadow_regs;
114 }
115 
cbe_get_iic_regs(struct device_node * np)116 struct cbe_iic_regs __iomem *cbe_get_iic_regs(struct device_node *np)
117 {
118 	struct cbe_regs_map *map = cbe_find_map(np);
119 	if (map == NULL)
120 		return NULL;
121 	return map->iic_regs;
122 }
123 
cbe_get_cpu_iic_regs(int cpu)124 struct cbe_iic_regs __iomem *cbe_get_cpu_iic_regs(int cpu)
125 {
126 	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
127 	if (map == NULL)
128 		return NULL;
129 	return map->iic_regs;
130 }
131 
cbe_get_mic_tm_regs(struct device_node * np)132 struct cbe_mic_tm_regs __iomem *cbe_get_mic_tm_regs(struct device_node *np)
133 {
134 	struct cbe_regs_map *map = cbe_find_map(np);
135 	if (map == NULL)
136 		return NULL;
137 	return map->mic_tm_regs;
138 }
139 
cbe_get_cpu_mic_tm_regs(int cpu)140 struct cbe_mic_tm_regs __iomem *cbe_get_cpu_mic_tm_regs(int cpu)
141 {
142 	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
143 	if (map == NULL)
144 		return NULL;
145 	return map->mic_tm_regs;
146 }
147 EXPORT_SYMBOL_GPL(cbe_get_cpu_mic_tm_regs);
148 
cbe_get_hw_thread_id(int cpu)149 u32 cbe_get_hw_thread_id(int cpu)
150 {
151 	return cbe_thread_map[cpu].thread_id;
152 }
153 EXPORT_SYMBOL_GPL(cbe_get_hw_thread_id);
154 
cbe_cpu_to_node(int cpu)155 u32 cbe_cpu_to_node(int cpu)
156 {
157 	return cbe_thread_map[cpu].cbe_id;
158 }
159 EXPORT_SYMBOL_GPL(cbe_cpu_to_node);
160 
cbe_node_to_cpu(int node)161 u32 cbe_node_to_cpu(int node)
162 {
163 	return cpumask_first(&cbe_local_mask[node]);
164 
165 }
166 EXPORT_SYMBOL_GPL(cbe_node_to_cpu);
167 
cbe_get_be_node(int cpu_id)168 static struct device_node *__init cbe_get_be_node(int cpu_id)
169 {
170 	struct device_node *np;
171 
172 	for_each_node_by_type (np, "be") {
173 		int len,i;
174 		const phandle *cpu_handle;
175 
176 		cpu_handle = of_get_property(np, "cpus", &len);
177 
178 		/*
179 		 * the CAB SLOF tree is non compliant, so we just assume
180 		 * there is only one node
181 		 */
182 		if (WARN_ON_ONCE(!cpu_handle))
183 			return np;
184 
185 		for (i = 0; i < len; i++) {
186 			struct device_node *ch_np = of_find_node_by_phandle(cpu_handle[i]);
187 			struct device_node *ci_np = of_get_cpu_node(cpu_id, NULL);
188 
189 			of_node_put(ch_np);
190 			of_node_put(ci_np);
191 
192 			if (ch_np == ci_np)
193 				return np;
194 		}
195 	}
196 
197 	return NULL;
198 }
199 
cbe_fill_regs_map(struct cbe_regs_map * map)200 static void __init cbe_fill_regs_map(struct cbe_regs_map *map)
201 {
202 	if(map->be_node) {
203 		struct device_node *be, *np, *parent_np;
204 
205 		be = map->be_node;
206 
207 		for_each_node_by_type(np, "pervasive") {
208 			parent_np = of_get_parent(np);
209 			if (parent_np == be)
210 				map->pmd_regs = of_iomap(np, 0);
211 			of_node_put(parent_np);
212 		}
213 
214 		for_each_node_by_type(np, "CBEA-Internal-Interrupt-Controller") {
215 			parent_np = of_get_parent(np);
216 			if (parent_np == be)
217 				map->iic_regs = of_iomap(np, 2);
218 			of_node_put(parent_np);
219 		}
220 
221 		for_each_node_by_type(np, "mic-tm") {
222 			parent_np = of_get_parent(np);
223 			if (parent_np == be)
224 				map->mic_tm_regs = of_iomap(np, 0);
225 			of_node_put(parent_np);
226 		}
227 	} else {
228 		struct device_node *cpu;
229 		/* That hack must die die die ! */
230 		const struct address_prop {
231 			unsigned long address;
232 			unsigned int len;
233 		} __attribute__((packed)) *prop;
234 
235 		cpu = map->cpu_node;
236 
237 		prop = of_get_property(cpu, "pervasive", NULL);
238 		if (prop != NULL)
239 			map->pmd_regs = ioremap(prop->address, prop->len);
240 
241 		prop = of_get_property(cpu, "iic", NULL);
242 		if (prop != NULL)
243 			map->iic_regs = ioremap(prop->address, prop->len);
244 
245 		prop = of_get_property(cpu, "mic-tm", NULL);
246 		if (prop != NULL)
247 			map->mic_tm_regs = ioremap(prop->address, prop->len);
248 	}
249 }
250 
251 
cbe_regs_init(void)252 void __init cbe_regs_init(void)
253 {
254 	int i;
255 	unsigned int thread_id;
256 	struct device_node *cpu;
257 
258 	/* Build local fast map of CPUs */
259 	for_each_possible_cpu(i) {
260 		cbe_thread_map[i].cpu_node = of_get_cpu_node(i, &thread_id);
261 		cbe_thread_map[i].be_node = cbe_get_be_node(i);
262 		cbe_thread_map[i].thread_id = thread_id;
263 	}
264 
265 	/* Find maps for each device tree CPU */
266 	for_each_node_by_type(cpu, "cpu") {
267 		struct cbe_regs_map *map;
268 		unsigned int cbe_id;
269 
270 		cbe_id = cbe_regs_map_count++;
271 		map = &cbe_regs_maps[cbe_id];
272 
273 		if (cbe_regs_map_count > MAX_CBE) {
274 			printk(KERN_ERR "cbe_regs: More BE chips than supported"
275 			       "!\n");
276 			cbe_regs_map_count--;
277 			of_node_put(cpu);
278 			return;
279 		}
280 		of_node_put(map->cpu_node);
281 		map->cpu_node = of_node_get(cpu);
282 
283 		for_each_possible_cpu(i) {
284 			struct cbe_thread_map *thread = &cbe_thread_map[i];
285 
286 			if (thread->cpu_node == cpu) {
287 				thread->regs = map;
288 				thread->cbe_id = cbe_id;
289 				map->be_node = thread->be_node;
290 				cpumask_set_cpu(i, &cbe_local_mask[cbe_id]);
291 				if(thread->thread_id == 0)
292 					cpumask_set_cpu(i, &cbe_first_online_cpu);
293 			}
294 		}
295 
296 		cbe_fill_regs_map(map);
297 	}
298 }
299 
300