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