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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
5f1ae4eb FW |
2 | /* |
3 | * ARM Specific GTDT table Support | |
4 | * | |
5 | * Copyright (C) 2016, Linaro Ltd. | |
6 | * Author: Daniel Lezcano <daniel.lezcano@linaro.org> | |
7 | * Fu Wei <fu.wei@linaro.org> | |
8 | * Hanjun Guo <hanjun.guo@linaro.org> | |
5f1ae4eb FW |
9 | */ |
10 | ||
11 | #include <linux/acpi.h> | |
12 | #include <linux/init.h> | |
a712c3ed | 13 | #include <linux/irqdomain.h> |
5f1ae4eb | 14 | #include <linux/kernel.h> |
ca9ae5ec | 15 | #include <linux/platform_device.h> |
5f1ae4eb FW |
16 | |
17 | #include <clocksource/arm_arch_timer.h> | |
18 | ||
19 | #undef pr_fmt | |
20 | #define pr_fmt(fmt) "ACPI GTDT: " fmt | |
21 | ||
22 | /** | |
23 | * struct acpi_gtdt_descriptor - Store the key info of GTDT for all functions | |
24 | * @gtdt: The pointer to the struct acpi_table_gtdt of GTDT table. | |
25 | * @gtdt_end: The pointer to the end of GTDT table. | |
26 | * @platform_timer: The pointer to the start of Platform Timer Structure | |
27 | * | |
28 | * The struct store the key info of GTDT table, it should be initialized by | |
29 | * acpi_gtdt_init. | |
30 | */ | |
31 | struct acpi_gtdt_descriptor { | |
32 | struct acpi_table_gtdt *gtdt; | |
33 | void *gtdt_end; | |
34 | void *platform_timer; | |
35 | }; | |
36 | ||
37 | static struct acpi_gtdt_descriptor acpi_gtdt_desc __initdata; | |
38 | ||
a712c3ed FW |
39 | static inline void *next_platform_timer(void *platform_timer) |
40 | { | |
41 | struct acpi_gtdt_header *gh = platform_timer; | |
42 | ||
43 | platform_timer += gh->length; | |
44 | if (platform_timer < acpi_gtdt_desc.gtdt_end) | |
45 | return platform_timer; | |
46 | ||
47 | return NULL; | |
48 | } | |
49 | ||
50 | #define for_each_platform_timer(_g) \ | |
51 | for (_g = acpi_gtdt_desc.platform_timer; _g; \ | |
52 | _g = next_platform_timer(_g)) | |
53 | ||
54 | static inline bool is_timer_block(void *platform_timer) | |
55 | { | |
56 | struct acpi_gtdt_header *gh = platform_timer; | |
57 | ||
58 | return gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK; | |
59 | } | |
60 | ||
ca9ae5ec FW |
61 | static inline bool is_non_secure_watchdog(void *platform_timer) |
62 | { | |
63 | struct acpi_gtdt_header *gh = platform_timer; | |
64 | struct acpi_gtdt_watchdog *wd = platform_timer; | |
65 | ||
66 | if (gh->type != ACPI_GTDT_TYPE_WATCHDOG) | |
67 | return false; | |
68 | ||
69 | return !(wd->timer_flags & ACPI_GTDT_WATCHDOG_SECURE); | |
70 | } | |
71 | ||
5f1ae4eb FW |
72 | static int __init map_gt_gsi(u32 interrupt, u32 flags) |
73 | { | |
74 | int trigger, polarity; | |
75 | ||
76 | trigger = (flags & ACPI_GTDT_INTERRUPT_MODE) ? ACPI_EDGE_SENSITIVE | |
77 | : ACPI_LEVEL_SENSITIVE; | |
78 | ||
79 | polarity = (flags & ACPI_GTDT_INTERRUPT_POLARITY) ? ACPI_ACTIVE_LOW | |
80 | : ACPI_ACTIVE_HIGH; | |
81 | ||
82 | return acpi_register_gsi(NULL, interrupt, trigger, polarity); | |
83 | } | |
84 | ||
85 | /** | |
86 | * acpi_gtdt_map_ppi() - Map the PPIs of per-cpu arch_timer. | |
87 | * @type: the type of PPI. | |
88 | * | |
89 | * Note: Secure state is not managed by the kernel on ARM64 systems. | |
90 | * So we only handle the non-secure timer PPIs, | |
91 | * ARCH_TIMER_PHYS_SECURE_PPI is treated as invalid type. | |
92 | * | |
93 | * Return: the mapped PPI value, 0 if error. | |
94 | */ | |
95 | int __init acpi_gtdt_map_ppi(int type) | |
96 | { | |
97 | struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; | |
98 | ||
99 | switch (type) { | |
100 | case ARCH_TIMER_PHYS_NONSECURE_PPI: | |
101 | return map_gt_gsi(gtdt->non_secure_el1_interrupt, | |
102 | gtdt->non_secure_el1_flags); | |
103 | case ARCH_TIMER_VIRT_PPI: | |
104 | return map_gt_gsi(gtdt->virtual_timer_interrupt, | |
105 | gtdt->virtual_timer_flags); | |
106 | ||
107 | case ARCH_TIMER_HYP_PPI: | |
108 | return map_gt_gsi(gtdt->non_secure_el2_interrupt, | |
109 | gtdt->non_secure_el2_flags); | |
110 | default: | |
111 | pr_err("Failed to map timer interrupt: invalid type.\n"); | |
112 | } | |
113 | ||
114 | return 0; | |
115 | } | |
116 | ||
117 | /** | |
118 | * acpi_gtdt_c3stop() - Got c3stop info from GTDT according to the type of PPI. | |
119 | * @type: the type of PPI. | |
120 | * | |
121 | * Return: true if the timer HW state is lost when a CPU enters an idle state, | |
122 | * false otherwise | |
123 | */ | |
124 | bool __init acpi_gtdt_c3stop(int type) | |
125 | { | |
126 | struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; | |
127 | ||
128 | switch (type) { | |
129 | case ARCH_TIMER_PHYS_NONSECURE_PPI: | |
130 | return !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON); | |
131 | ||
132 | case ARCH_TIMER_VIRT_PPI: | |
133 | return !(gtdt->virtual_timer_flags & ACPI_GTDT_ALWAYS_ON); | |
134 | ||
135 | case ARCH_TIMER_HYP_PPI: | |
136 | return !(gtdt->non_secure_el2_flags & ACPI_GTDT_ALWAYS_ON); | |
137 | ||
138 | default: | |
139 | pr_err("Failed to get c3stop info: invalid type.\n"); | |
140 | } | |
141 | ||
142 | return false; | |
143 | } | |
144 | ||
145 | /** | |
146 | * acpi_gtdt_init() - Get the info of GTDT table to prepare for further init. | |
147 | * @table: The pointer to GTDT table. | |
148 | * @platform_timer_count: It points to a integer variable which is used | |
149 | * for storing the number of platform timers. | |
150 | * This pointer could be NULL, if the caller | |
151 | * doesn't need this info. | |
152 | * | |
153 | * Return: 0 if success, -EINVAL if error. | |
154 | */ | |
155 | int __init acpi_gtdt_init(struct acpi_table_header *table, | |
156 | int *platform_timer_count) | |
157 | { | |
158 | void *platform_timer; | |
159 | struct acpi_table_gtdt *gtdt; | |
160 | ||
161 | gtdt = container_of(table, struct acpi_table_gtdt, header); | |
162 | acpi_gtdt_desc.gtdt = gtdt; | |
163 | acpi_gtdt_desc.gtdt_end = (void *)table + table->length; | |
164 | acpi_gtdt_desc.platform_timer = NULL; | |
165 | if (platform_timer_count) | |
166 | *platform_timer_count = 0; | |
167 | ||
168 | if (table->revision < 2) { | |
169 | pr_warn("Revision:%d doesn't support Platform Timers.\n", | |
170 | table->revision); | |
171 | return 0; | |
172 | } | |
173 | ||
174 | if (!gtdt->platform_timer_count) { | |
175 | pr_debug("No Platform Timer.\n"); | |
176 | return 0; | |
177 | } | |
178 | ||
179 | platform_timer = (void *)gtdt + gtdt->platform_timer_offset; | |
180 | if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) { | |
181 | pr_err(FW_BUG "invalid timer data.\n"); | |
182 | return -EINVAL; | |
183 | } | |
184 | acpi_gtdt_desc.platform_timer = platform_timer; | |
185 | if (platform_timer_count) | |
186 | *platform_timer_count = gtdt->platform_timer_count; | |
187 | ||
188 | return 0; | |
189 | } | |
a712c3ed FW |
190 | |
191 | static int __init gtdt_parse_timer_block(struct acpi_gtdt_timer_block *block, | |
192 | struct arch_timer_mem *timer_mem) | |
193 | { | |
194 | int i; | |
195 | struct arch_timer_mem_frame *frame; | |
196 | struct acpi_gtdt_timer_entry *gtdt_frame; | |
197 | ||
198 | if (!block->timer_count) { | |
ee10b9c9 | 199 | pr_err(FW_BUG "GT block present, but frame count is zero.\n"); |
a712c3ed FW |
200 | return -ENODEV; |
201 | } | |
202 | ||
203 | if (block->timer_count > ARCH_TIMER_MEM_MAX_FRAMES) { | |
204 | pr_err(FW_BUG "GT block lists %d frames, ACPI spec only allows 8\n", | |
205 | block->timer_count); | |
206 | return -EINVAL; | |
207 | } | |
208 | ||
209 | timer_mem->cntctlbase = (phys_addr_t)block->block_address; | |
210 | /* | |
211 | * The CNTCTLBase frame is 4KB (register offsets 0x000 - 0xFFC). | |
212 | * See ARM DDI 0487A.k_iss10775, page I1-5129, Table I1-3 | |
213 | * "CNTCTLBase memory map". | |
214 | */ | |
215 | timer_mem->size = SZ_4K; | |
216 | ||
217 | gtdt_frame = (void *)block + block->timer_offset; | |
218 | if (gtdt_frame + block->timer_count != (void *)block + block->header.length) | |
219 | return -EINVAL; | |
220 | ||
221 | /* | |
222 | * Get the GT timer Frame data for every GT Block Timer | |
223 | */ | |
224 | for (i = 0; i < block->timer_count; i++, gtdt_frame++) { | |
225 | if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER) | |
226 | continue; | |
227 | if (gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES || | |
228 | !gtdt_frame->base_address || !gtdt_frame->timer_interrupt) | |
229 | goto error; | |
230 | ||
231 | frame = &timer_mem->frame[gtdt_frame->frame_number]; | |
232 | ||
233 | /* duplicate frame */ | |
234 | if (frame->valid) | |
235 | goto error; | |
236 | ||
237 | frame->phys_irq = map_gt_gsi(gtdt_frame->timer_interrupt, | |
238 | gtdt_frame->timer_flags); | |
239 | if (frame->phys_irq <= 0) { | |
240 | pr_warn("failed to map physical timer irq in frame %d.\n", | |
241 | gtdt_frame->frame_number); | |
242 | goto error; | |
243 | } | |
244 | ||
245 | if (gtdt_frame->virtual_timer_interrupt) { | |
246 | frame->virt_irq = | |
247 | map_gt_gsi(gtdt_frame->virtual_timer_interrupt, | |
248 | gtdt_frame->virtual_timer_flags); | |
249 | if (frame->virt_irq <= 0) { | |
250 | pr_warn("failed to map virtual timer irq in frame %d.\n", | |
251 | gtdt_frame->frame_number); | |
252 | goto error; | |
253 | } | |
254 | } else { | |
255 | pr_debug("virtual timer in frame %d not implemented.\n", | |
256 | gtdt_frame->frame_number); | |
257 | } | |
258 | ||
259 | frame->cntbase = gtdt_frame->base_address; | |
260 | /* | |
261 | * The CNTBaseN frame is 4KB (register offsets 0x000 - 0xFFC). | |
262 | * See ARM DDI 0487A.k_iss10775, page I1-5130, Table I1-4 | |
263 | * "CNTBaseN memory map". | |
264 | */ | |
265 | frame->size = SZ_4K; | |
266 | frame->valid = true; | |
267 | } | |
268 | ||
269 | return 0; | |
270 | ||
271 | error: | |
272 | do { | |
273 | if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER || | |
274 | gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES) | |
275 | continue; | |
276 | ||
277 | frame = &timer_mem->frame[gtdt_frame->frame_number]; | |
278 | ||
279 | if (frame->phys_irq > 0) | |
280 | acpi_unregister_gsi(gtdt_frame->timer_interrupt); | |
281 | frame->phys_irq = 0; | |
282 | ||
283 | if (frame->virt_irq > 0) | |
284 | acpi_unregister_gsi(gtdt_frame->virtual_timer_interrupt); | |
285 | frame->virt_irq = 0; | |
286 | } while (i-- >= 0 && gtdt_frame--); | |
287 | ||
288 | return -EINVAL; | |
289 | } | |
290 | ||
291 | /** | |
292 | * acpi_arch_timer_mem_init() - Get the info of all GT blocks in GTDT table. | |
293 | * @timer_mem: The pointer to the array of struct arch_timer_mem for returning | |
294 | * the result of parsing. The element number of this array should | |
295 | * be platform_timer_count(the total number of platform timers). | |
296 | * @timer_count: It points to a integer variable which is used for storing the | |
297 | * number of GT blocks we have parsed. | |
298 | * | |
299 | * Return: 0 if success, -EINVAL/-ENODEV if error. | |
300 | */ | |
301 | int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, | |
302 | int *timer_count) | |
303 | { | |
304 | int ret; | |
305 | void *platform_timer; | |
306 | ||
307 | *timer_count = 0; | |
308 | for_each_platform_timer(platform_timer) { | |
309 | if (is_timer_block(platform_timer)) { | |
310 | ret = gtdt_parse_timer_block(platform_timer, timer_mem); | |
311 | if (ret) | |
312 | return ret; | |
313 | timer_mem++; | |
314 | (*timer_count)++; | |
315 | } | |
316 | } | |
317 | ||
318 | if (*timer_count) | |
319 | pr_info("found %d memory-mapped timer block(s).\n", | |
320 | *timer_count); | |
321 | ||
322 | return 0; | |
323 | } | |
ca9ae5ec FW |
324 | |
325 | /* | |
326 | * Initialize a SBSA generic Watchdog platform device info from GTDT | |
327 | */ | |
328 | static int __init gtdt_import_sbsa_gwdt(struct acpi_gtdt_watchdog *wd, | |
329 | int index) | |
330 | { | |
331 | struct platform_device *pdev; | |
332 | int irq = map_gt_gsi(wd->timer_interrupt, wd->timer_flags); | |
333 | ||
334 | /* | |
335 | * According to SBSA specification the size of refresh and control | |
336 | * frames of SBSA Generic Watchdog is SZ_4K(Offset 0x000 – 0xFFF). | |
337 | */ | |
338 | struct resource res[] = { | |
339 | DEFINE_RES_MEM(wd->control_frame_address, SZ_4K), | |
340 | DEFINE_RES_MEM(wd->refresh_frame_address, SZ_4K), | |
341 | DEFINE_RES_IRQ(irq), | |
342 | }; | |
343 | int nr_res = ARRAY_SIZE(res); | |
344 | ||
345 | pr_debug("found a Watchdog (0x%llx/0x%llx gsi:%u flags:0x%x).\n", | |
346 | wd->refresh_frame_address, wd->control_frame_address, | |
347 | wd->timer_interrupt, wd->timer_flags); | |
348 | ||
349 | if (!(wd->refresh_frame_address && wd->control_frame_address)) { | |
350 | pr_err(FW_BUG "failed to get the Watchdog base address.\n"); | |
351 | acpi_unregister_gsi(wd->timer_interrupt); | |
352 | return -EINVAL; | |
353 | } | |
354 | ||
355 | if (irq <= 0) { | |
356 | pr_warn("failed to map the Watchdog interrupt.\n"); | |
357 | nr_res--; | |
358 | } | |
359 | ||
360 | /* | |
361 | * Add a platform device named "sbsa-gwdt" to match the platform driver. | |
362 | * "sbsa-gwdt": SBSA(Server Base System Architecture) Generic Watchdog | |
363 | * The platform driver can get device info below by matching this name. | |
364 | */ | |
365 | pdev = platform_device_register_simple("sbsa-gwdt", index, res, nr_res); | |
366 | if (IS_ERR(pdev)) { | |
367 | acpi_unregister_gsi(wd->timer_interrupt); | |
368 | return PTR_ERR(pdev); | |
369 | } | |
370 | ||
371 | return 0; | |
372 | } | |
373 | ||
374 | static int __init gtdt_sbsa_gwdt_init(void) | |
375 | { | |
376 | void *platform_timer; | |
377 | struct acpi_table_header *table; | |
378 | int ret, timer_count, gwdt_count = 0; | |
379 | ||
380 | if (acpi_disabled) | |
381 | return 0; | |
382 | ||
383 | if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_GTDT, 0, &table))) | |
384 | return -EINVAL; | |
385 | ||
386 | /* | |
387 | * Note: Even though the global variable acpi_gtdt_desc has been | |
388 | * initialized by acpi_gtdt_init() while initializing the arch timers, | |
389 | * when we call this function to get SBSA watchdogs info from GTDT, the | |
390 | * pointers stashed in it are stale (since they are early temporary | |
391 | * mappings carried out before acpi_permanent_mmap is set) and we need | |
392 | * to re-initialize them with permanent mapped pointer values to let the | |
393 | * GTDT parsing possible. | |
394 | */ | |
395 | ret = acpi_gtdt_init(table, &timer_count); | |
396 | if (ret || !timer_count) | |
397 | return ret; | |
398 | ||
399 | for_each_platform_timer(platform_timer) { | |
400 | if (is_non_secure_watchdog(platform_timer)) { | |
401 | ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count); | |
402 | if (ret) | |
403 | break; | |
404 | gwdt_count++; | |
405 | } | |
406 | } | |
407 | ||
408 | if (gwdt_count) | |
409 | pr_info("found %d SBSA generic Watchdog(s).\n", gwdt_count); | |
410 | ||
411 | return ret; | |
412 | } | |
413 | ||
414 | device_initcall(gtdt_sbsa_gwdt_init); |