1 /*
2 * ARM64 Specific Low-Level ACPI Boot Support
3 *
4 * Copyright (C) 2013-2014, Linaro Ltd.
5 * Author: Al Stone <al.stone@linaro.org>
6 * Author: Graeme Gregory <graeme.gregory@linaro.org>
7 * Author: Hanjun Guo <hanjun.guo@linaro.org>
8 * Author: Tomasz Nowicki <tomasz.nowicki@linaro.org>
9 * Author: Naresh Bhat <naresh.bhat@linaro.org>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
14 */
15
16 #define pr_fmt(fmt) "ACPI: " fmt
17
18 #include <linux/acpi.h>
19 #include <linux/bootmem.h>
20 #include <linux/cpumask.h>
21 #include <linux/init.h>
22 #include <linux/irq.h>
23 #include <linux/irqdomain.h>
24 #include <linux/memblock.h>
25 #include <linux/of_fdt.h>
26 #include <linux/smp.h>
27
28 #include <asm/cputype.h>
29 #include <asm/cpu_ops.h>
30 #include <asm/smp_plat.h>
31
32 int acpi_noirq = 1; /* skip ACPI IRQ initialization */
33 int acpi_disabled = 1;
34 EXPORT_SYMBOL(acpi_disabled);
35
36 int acpi_pci_disabled = 1; /* skip ACPI PCI scan and IRQ initialization */
37 EXPORT_SYMBOL(acpi_pci_disabled);
38
39 /* Processors with enabled flag and sane MPIDR */
40 static int enabled_cpus;
41
42 /* Boot CPU is valid or not in MADT */
43 static bool bootcpu_valid __initdata;
44
45 static bool param_acpi_off __initdata;
46 static bool param_acpi_force __initdata;
47
parse_acpi(char * arg)48 static int __init parse_acpi(char *arg)
49 {
50 if (!arg)
51 return -EINVAL;
52
53 /* "acpi=off" disables both ACPI table parsing and interpreter */
54 if (strcmp(arg, "off") == 0)
55 param_acpi_off = true;
56 else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */
57 param_acpi_force = true;
58 else
59 return -EINVAL; /* Core will print when we return error */
60
61 return 0;
62 }
63 early_param("acpi", parse_acpi);
64
dt_scan_depth1_nodes(unsigned long node,const char * uname,int depth,void * data)65 static int __init dt_scan_depth1_nodes(unsigned long node,
66 const char *uname, int depth,
67 void *data)
68 {
69 /*
70 * Return 1 as soon as we encounter a node at depth 1 that is
71 * not the /chosen node.
72 */
73 if (depth == 1 && (strcmp(uname, "chosen") != 0))
74 return 1;
75 return 0;
76 }
77
78 /*
79 * __acpi_map_table() will be called before page_init(), so early_ioremap()
80 * or early_memremap() should be called here to for ACPI table mapping.
81 */
__acpi_map_table(unsigned long phys,unsigned long size)82 char *__init __acpi_map_table(unsigned long phys, unsigned long size)
83 {
84 if (!size)
85 return NULL;
86
87 return early_memremap(phys, size);
88 }
89
__acpi_unmap_table(char * map,unsigned long size)90 void __init __acpi_unmap_table(char *map, unsigned long size)
91 {
92 if (!map || !size)
93 return;
94
95 early_memunmap(map, size);
96 }
97
98 /**
99 * acpi_map_gic_cpu_interface - generates a logical cpu number
100 * and map to MPIDR represented by GICC structure
101 */
102 static void __init
acpi_map_gic_cpu_interface(struct acpi_madt_generic_interrupt * processor)103 acpi_map_gic_cpu_interface(struct acpi_madt_generic_interrupt *processor)
104 {
105 int i;
106 u64 mpidr = processor->arm_mpidr & MPIDR_HWID_BITMASK;
107 bool enabled = !!(processor->flags & ACPI_MADT_ENABLED);
108
109 if (mpidr == INVALID_HWID) {
110 pr_info("Skip MADT cpu entry with invalid MPIDR\n");
111 return;
112 }
113
114 total_cpus++;
115 if (!enabled)
116 return;
117
118 if (enabled_cpus >= NR_CPUS) {
119 pr_warn("NR_CPUS limit of %d reached, Processor %d/0x%llx ignored.\n",
120 NR_CPUS, total_cpus, mpidr);
121 return;
122 }
123
124 /* Check if GICC structure of boot CPU is available in the MADT */
125 if (cpu_logical_map(0) == mpidr) {
126 if (bootcpu_valid) {
127 pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
128 mpidr);
129 return;
130 }
131
132 bootcpu_valid = true;
133 }
134
135 /*
136 * Duplicate MPIDRs are a recipe for disaster. Scan
137 * all initialized entries and check for
138 * duplicates. If any is found just ignore the CPU.
139 */
140 for (i = 1; i < enabled_cpus; i++) {
141 if (cpu_logical_map(i) == mpidr) {
142 pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
143 mpidr);
144 return;
145 }
146 }
147
148 if (!acpi_psci_present())
149 return;
150
151 cpu_ops[enabled_cpus] = cpu_get_ops("psci");
152 /* CPU 0 was already initialized */
153 if (enabled_cpus) {
154 if (!cpu_ops[enabled_cpus])
155 return;
156
157 if (cpu_ops[enabled_cpus]->cpu_init(NULL, enabled_cpus))
158 return;
159
160 /* map the logical cpu id to cpu MPIDR */
161 cpu_logical_map(enabled_cpus) = mpidr;
162 }
163
164 enabled_cpus++;
165 }
166
167 static int __init
acpi_parse_gic_cpu_interface(struct acpi_subtable_header * header,const unsigned long end)168 acpi_parse_gic_cpu_interface(struct acpi_subtable_header *header,
169 const unsigned long end)
170 {
171 struct acpi_madt_generic_interrupt *processor;
172
173 processor = (struct acpi_madt_generic_interrupt *)header;
174
175 if (BAD_MADT_ENTRY(processor, end))
176 return -EINVAL;
177
178 acpi_table_print_madt_entry(header);
179 acpi_map_gic_cpu_interface(processor);
180 return 0;
181 }
182
183 /* Parse GIC cpu interface entries in MADT for SMP init */
acpi_init_cpus(void)184 void __init acpi_init_cpus(void)
185 {
186 int count, i;
187
188 /*
189 * do a partial walk of MADT to determine how many CPUs
190 * we have including disabled CPUs, and get information
191 * we need for SMP init
192 */
193 count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
194 acpi_parse_gic_cpu_interface, 0);
195
196 if (!count) {
197 pr_err("No GIC CPU interface entries present\n");
198 return;
199 } else if (count < 0) {
200 pr_err("Error parsing GIC CPU interface entry\n");
201 return;
202 }
203
204 if (!bootcpu_valid) {
205 pr_err("MADT missing boot CPU MPIDR, not enabling secondaries\n");
206 return;
207 }
208
209 for (i = 0; i < enabled_cpus; i++)
210 set_cpu_possible(i, true);
211
212 /* Make boot-up look pretty */
213 pr_info("%d CPUs enabled, %d CPUs total\n", enabled_cpus, total_cpus);
214 }
215
216 /*
217 * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity
218 * checks on it
219 *
220 * Return 0 on success, <0 on failure
221 */
acpi_fadt_sanity_check(void)222 static int __init acpi_fadt_sanity_check(void)
223 {
224 struct acpi_table_header *table;
225 struct acpi_table_fadt *fadt;
226 acpi_status status;
227 acpi_size tbl_size;
228 int ret = 0;
229
230 /*
231 * FADT is required on arm64; retrieve it to check its presence
232 * and carry out revision and ACPI HW reduced compliancy tests
233 */
234 status = acpi_get_table_with_size(ACPI_SIG_FADT, 0, &table, &tbl_size);
235 if (ACPI_FAILURE(status)) {
236 const char *msg = acpi_format_exception(status);
237
238 pr_err("Failed to get FADT table, %s\n", msg);
239 return -ENODEV;
240 }
241
242 fadt = (struct acpi_table_fadt *)table;
243
244 /*
245 * Revision in table header is the FADT Major revision, and there
246 * is a minor revision of FADT which was introduced by ACPI 5.1,
247 * we only deal with ACPI 5.1 or newer revision to get GIC and SMP
248 * boot protocol configuration data.
249 */
250 if (table->revision < 5 ||
251 (table->revision == 5 && fadt->minor_revision < 1)) {
252 pr_err("Unsupported FADT revision %d.%d, should be 5.1+\n",
253 table->revision, fadt->minor_revision);
254 ret = -EINVAL;
255 goto out;
256 }
257
258 if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) {
259 pr_err("FADT not ACPI hardware reduced compliant\n");
260 ret = -EINVAL;
261 }
262
263 out:
264 /*
265 * acpi_get_table_with_size() creates FADT table mapping that
266 * should be released after parsing and before resuming boot
267 */
268 early_acpi_os_unmap_memory(table, tbl_size);
269 return ret;
270 }
271
272 /*
273 * acpi_boot_table_init() called from setup_arch(), always.
274 * 1. find RSDP and get its address, and then find XSDT
275 * 2. extract all tables and checksums them all
276 * 3. check ACPI FADT revision
277 * 4. check ACPI FADT HW reduced flag
278 *
279 * We can parse ACPI boot-time tables such as MADT after
280 * this function is called.
281 *
282 * On return ACPI is enabled if either:
283 *
284 * - ACPI tables are initialized and sanity checks passed
285 * - acpi=force was passed in the command line and ACPI was not disabled
286 * explicitly through acpi=off command line parameter
287 *
288 * ACPI is disabled on function return otherwise
289 */
acpi_boot_table_init(void)290 void __init acpi_boot_table_init(void)
291 {
292 /*
293 * Enable ACPI instead of device tree unless
294 * - ACPI has been disabled explicitly (acpi=off), or
295 * - the device tree is not empty (it has more than just a /chosen node)
296 * and ACPI has not been force enabled (acpi=force)
297 */
298 if (param_acpi_off ||
299 (!param_acpi_force && of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
300 return;
301
302 /*
303 * ACPI is disabled at this point. Enable it in order to parse
304 * the ACPI tables and carry out sanity checks
305 */
306 enable_acpi();
307
308 /*
309 * If ACPI tables are initialized and FADT sanity checks passed,
310 * leave ACPI enabled and carry on booting; otherwise disable ACPI
311 * on initialization error.
312 * If acpi=force was passed on the command line it forces ACPI
313 * to be enabled even if its initialization failed.
314 */
315 if (acpi_table_init() || acpi_fadt_sanity_check()) {
316 pr_err("Failed to init ACPI tables\n");
317 if (!param_acpi_force)
318 disable_acpi();
319 }
320 }
321
acpi_gic_init(void)322 void __init acpi_gic_init(void)
323 {
324 struct acpi_table_header *table;
325 acpi_status status;
326 acpi_size tbl_size;
327 int err;
328
329 if (acpi_disabled)
330 return;
331
332 status = acpi_get_table_with_size(ACPI_SIG_MADT, 0, &table, &tbl_size);
333 if (ACPI_FAILURE(status)) {
334 const char *msg = acpi_format_exception(status);
335
336 pr_err("Failed to get MADT table, %s\n", msg);
337 return;
338 }
339
340 err = gic_v2_acpi_init(table);
341 if (err)
342 pr_err("Failed to initialize GIC IRQ controller");
343
344 early_acpi_os_unmap_memory((char *)table, tbl_size);
345 }
346