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 */
28static 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];
37static int cbe_regs_map_count;
38
39static 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
48static cpumask_t cbe_local_mask[MAX_CBE] = { [0 ... MAX_CBE-1] = {CPU_BITS_NONE} };
49static cpumask_t cbe_first_online_cpu = { CPU_BITS_NONE };
50
51static 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
81struct 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}
88EXPORT_SYMBOL_GPL(cbe_get_pmd_regs);
89
90struct 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}
97EXPORT_SYMBOL_GPL(cbe_get_cpu_pmd_regs);
98
99struct 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
107struct 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
115struct 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
123struct 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
131struct 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
139struct 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}
146EXPORT_SYMBOL_GPL(cbe_get_cpu_mic_tm_regs);
147
148u32 cbe_get_hw_thread_id(int cpu)
149{
150	return cbe_thread_map[cpu].thread_id;
151}
152EXPORT_SYMBOL_GPL(cbe_get_hw_thread_id);
153
154u32 cbe_cpu_to_node(int cpu)
155{
156	return cbe_thread_map[cpu].cbe_id;
157}
158EXPORT_SYMBOL_GPL(cbe_cpu_to_node);
159
160u32 cbe_node_to_cpu(int node)
161{
162	return cpumask_first(&cbe_local_mask[node]);
163
164}
165EXPORT_SYMBOL_GPL(cbe_node_to_cpu);
166
167static 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
199static 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
251void __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