1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * ARM64 Specific Low-Level ACPI Boot Support
4 *
5 * Copyright (C) 2013-2014, Linaro Ltd.
6 * Author: Al Stone <al.stone@linaro.org>
7 * Author: Graeme Gregory <graeme.gregory@linaro.org>
8 * Author: Hanjun Guo <hanjun.guo@linaro.org>
9 * Author: Tomasz Nowicki <tomasz.nowicki@linaro.org>
10 * Author: Naresh Bhat <naresh.bhat@linaro.org>
11 */
12
13 #define pr_fmt(fmt) "ACPI: " fmt
14
15 #include <linux/acpi.h>
16 #include <linux/cpumask.h>
17 #include <linux/efi.h>
18 #include <linux/efi-bgrt.h>
19 #include <linux/init.h>
20 #include <linux/irq.h>
21 #include <linux/irqdomain.h>
22 #include <linux/memblock.h>
23 #include <linux/of_fdt.h>
24 #include <linux/smp.h>
25 #include <linux/serial_core.h>
26
27 #include <acpi/ghes.h>
28 #include <asm/cputype.h>
29 #include <asm/cpu_ops.h>
30 #include <asm/daifflags.h>
31 #include <asm/pgtable.h>
32 #include <asm/smp_plat.h>
33
34 int acpi_noirq = 1; /* skip ACPI IRQ initialization */
35 int acpi_disabled = 1;
36 EXPORT_SYMBOL(acpi_disabled);
37
38 int acpi_pci_disabled = 1; /* skip ACPI PCI scan and IRQ initialization */
39 EXPORT_SYMBOL(acpi_pci_disabled);
40
41 static bool param_acpi_off __initdata;
42 static bool param_acpi_on __initdata;
43 static bool param_acpi_force __initdata;
44
45 static int __init parse_acpi(char *arg)
46 {
47 if (!arg)
48 return -EINVAL;
49
50 /* "acpi=off" disables both ACPI table parsing and interpreter */
51 if (strcmp(arg, "off") == 0)
52 param_acpi_off = true;
53 else if (strcmp(arg, "on") == 0) /* prefer ACPI over DT */
54 param_acpi_on = true;
55 else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */
56 param_acpi_force = true;
57 else
58 return -EINVAL; /* Core will print when we return error */
59
60 return 0;
61 }
62 early_param("acpi", parse_acpi);
63
64 static int __init dt_scan_depth1_nodes(unsigned long node,
65 const char *uname, int depth,
66 void *data)
67 {
68 /*
69 * Ignore anything not directly under the root node; we'll
70 * catch its parent instead.
71 */
72 if (depth != 1)
73 return 0;
74
75 if (strcmp(uname, "chosen") == 0)
76 return 0;
77
78 if (strcmp(uname, "hypervisor") == 0 &&
79 of_flat_dt_is_compatible(node, "xen,xen"))
80 return 0;
81
82 /*
83 * This node at depth 1 is neither a chosen node nor a xen node,
84 * which we do not expect.
85 */
86 return 1;
87 }
88
89 /*
90 * __acpi_map_table() will be called before page_init(), so early_ioremap()
91 * or early_memremap() should be called here to for ACPI table mapping.
92 */
93 void __init __iomem *__acpi_map_table(unsigned long phys, unsigned long size)
94 {
95 if (!size)
96 return NULL;
97
98 return early_memremap(phys, size);
99 }
100
101 void __init __acpi_unmap_table(void __iomem *map, unsigned long size)
102 {
103 if (!map || !size)
104 return;
105
106 early_memunmap(map, size);
107 }
108
109 bool __init acpi_psci_present(void)
110 {
111 return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_COMPLIANT;
112 }
113
114 /* Whether HVC must be used instead of SMC as the PSCI conduit */
115 bool acpi_psci_use_hvc(void)
116 {
117 return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_USE_HVC;
118 }
119
120 /*
121 * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity
122 * checks on it
123 *
124 * Return 0 on success, <0 on failure
125 */
126 static int __init acpi_fadt_sanity_check(void)
127 {
128 struct acpi_table_header *table;
129 struct acpi_table_fadt *fadt;
130 acpi_status status;
131 int ret = 0;
132
133 /*
134 * FADT is required on arm64; retrieve it to check its presence
135 * and carry out revision and ACPI HW reduced compliancy tests
136 */
137 status = acpi_get_table(ACPI_SIG_FADT, 0, &table);
138 if (ACPI_FAILURE(status)) {
139 const char *msg = acpi_format_exception(status);
140
141 pr_err("Failed to get FADT table, %s\n", msg);
142 return -ENODEV;
143 }
144
145 fadt = (struct acpi_table_fadt *)table;
146
147 /*
148 * Revision in table header is the FADT Major revision, and there
149 * is a minor revision of FADT which was introduced by ACPI 5.1,
150 * we only deal with ACPI 5.1 or newer revision to get GIC and SMP
151 * boot protocol configuration data.
152 */
153 if (table->revision < 5 ||
154 (table->revision == 5 && fadt->minor_revision < 1)) {
155 pr_err(FW_BUG "Unsupported FADT revision %d.%d, should be 5.1+\n",
156 table->revision, fadt->minor_revision);
157
158 if (!fadt->arm_boot_flags) {
159 ret = -EINVAL;
160 goto out;
161 }
162 pr_err("FADT has ARM boot flags set, assuming 5.1\n");
163 }
164
165 if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) {
166 pr_err("FADT not ACPI hardware reduced compliant\n");
167 ret = -EINVAL;
168 }
169
170 out:
171 /*
172 * acpi_get_table() creates FADT table mapping that
173 * should be released after parsing and before resuming boot
174 */
175 acpi_put_table(table);
176 return ret;
177 }
178
179 /*
180 * acpi_boot_table_init() called from setup_arch(), always.
181 * 1. find RSDP and get its address, and then find XSDT
182 * 2. extract all tables and checksums them all
183 * 3. check ACPI FADT revision
184 * 4. check ACPI FADT HW reduced flag
185 *
186 * We can parse ACPI boot-time tables such as MADT after
187 * this function is called.
188 *
189 * On return ACPI is enabled if either:
190 *
191 * - ACPI tables are initialized and sanity checks passed
192 * - acpi=force was passed in the command line and ACPI was not disabled
193 * explicitly through acpi=off command line parameter
194 *
195 * ACPI is disabled on function return otherwise
196 */
197 void __init acpi_boot_table_init(void)
198 {
199 /*
200 * Enable ACPI instead of device tree unless
201 * - ACPI has been disabled explicitly (acpi=off), or
202 * - the device tree is not empty (it has more than just a /chosen node,
203 * and a /hypervisor node when running on Xen)
204 * and ACPI has not been [force] enabled (acpi=on|force)
205 */
206 if (param_acpi_off ||
207 (!param_acpi_on && !param_acpi_force &&
208 of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
209 goto done;
210
211 /*
212 * ACPI is disabled at this point. Enable it in order to parse
213 * the ACPI tables and carry out sanity checks
214 */
215 enable_acpi();
216
217 /*
218 * If ACPI tables are initialized and FADT sanity checks passed,
219 * leave ACPI enabled and carry on booting; otherwise disable ACPI
220 * on initialization error.
221 * If acpi=force was passed on the command line it forces ACPI
222 * to be enabled even if its initialization failed.
223 */
224 if (acpi_table_init() || acpi_fadt_sanity_check()) {
225 pr_err("Failed to init ACPI tables\n");
226 if (!param_acpi_force)
227 disable_acpi();
228 }
229
230 done:
231 if (acpi_disabled) {
232 if (earlycon_acpi_spcr_enable)
233 early_init_dt_scan_chosen_stdout();
234 } else {
235 acpi_parse_spcr(earlycon_acpi_spcr_enable, true);
236 if (IS_ENABLED(CONFIG_ACPI_BGRT))
237 acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt);
238 }
239 }
240
241 pgprot_t __acpi_get_mem_attribute(phys_addr_t addr)
242 {
243 /*
244 * According to "Table 8 Map: EFI memory types to AArch64 memory
245 * types" of UEFI 2.5 section 2.3.6.1, each EFI memory type is
246 * mapped to a corresponding MAIR attribute encoding.
247 * The EFI memory attribute advises all possible capabilities
248 * of a memory region. We use the most efficient capability.
249 */
250
251 u64 attr;
252
253 attr = efi_mem_attributes(addr);
254 if (attr & EFI_MEMORY_WB)
255 return PAGE_KERNEL;
256 if (attr & EFI_MEMORY_WT)
257 return __pgprot(PROT_NORMAL_WT);
258 if (attr & EFI_MEMORY_WC)
259 return __pgprot(PROT_NORMAL_NC);
260 return __pgprot(PROT_DEVICE_nGnRnE);
261 }
262
263 /*
264 * Claim Synchronous External Aborts as a firmware first notification.
265 *
266 * Used by KVM and the arch do_sea handler.
267 * @regs may be NULL when called from process context.
268 */
269 int apei_claim_sea(struct pt_regs *regs)
270 {
271 int err = -ENOENT;
272 unsigned long current_flags;
273
274 if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES))
275 return err;
276
277 current_flags = local_daif_save_flags();
278
279 /*
280 * SEA can interrupt SError, mask it and describe this as an NMI so
281 * that APEI defers the handling.
282 */
283 local_daif_restore(DAIF_ERRCTX);
284 nmi_enter();
285 err = ghes_notify_sea();
286 nmi_exit();
287 local_daif_restore(current_flags);
288
289 return err;
290 }