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 #ifdef CONFIG_ACPI_APEI
33 # include <linux/efi.h>
34 # include <asm/pgtable.h>
35 #endif
36
37 int acpi_noirq = 1; /* skip ACPI IRQ initialization */
38 int acpi_disabled = 1;
39 EXPORT_SYMBOL(acpi_disabled);
40
41 int acpi_pci_disabled = 1; /* skip ACPI PCI scan and IRQ initialization */
42 EXPORT_SYMBOL(acpi_pci_disabled);
43
44 static bool param_acpi_off __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, "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
dt_scan_depth1_nodes(unsigned long node,const char * uname,int depth,void * data)64 static int __init dt_scan_depth1_nodes(unsigned long node,
65 const char *uname, int depth,
66 void *data)
67 {
68 /*
69 * Return 1 as soon as we encounter a node at depth 1 that is
70 * not the /chosen node.
71 */
72 if (depth == 1 && (strcmp(uname, "chosen") != 0))
73 return 1;
74 return 0;
75 }
76
77 /*
78 * __acpi_map_table() will be called before page_init(), so early_ioremap()
79 * or early_memremap() should be called here to for ACPI table mapping.
80 */
__acpi_map_table(unsigned long phys,unsigned long size)81 char *__init __acpi_map_table(unsigned long phys, unsigned long size)
82 {
83 if (!size)
84 return NULL;
85
86 return early_memremap(phys, size);
87 }
88
__acpi_unmap_table(char * map,unsigned long size)89 void __init __acpi_unmap_table(char *map, unsigned long size)
90 {
91 if (!map || !size)
92 return;
93
94 early_memunmap(map, size);
95 }
96
acpi_psci_present(void)97 bool __init acpi_psci_present(void)
98 {
99 return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_COMPLIANT;
100 }
101
102 /* Whether HVC must be used instead of SMC as the PSCI conduit */
acpi_psci_use_hvc(void)103 bool __init acpi_psci_use_hvc(void)
104 {
105 return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_USE_HVC;
106 }
107
108 /*
109 * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity
110 * checks on it
111 *
112 * Return 0 on success, <0 on failure
113 */
acpi_fadt_sanity_check(void)114 static int __init acpi_fadt_sanity_check(void)
115 {
116 struct acpi_table_header *table;
117 struct acpi_table_fadt *fadt;
118 acpi_status status;
119 acpi_size tbl_size;
120 int ret = 0;
121
122 /*
123 * FADT is required on arm64; retrieve it to check its presence
124 * and carry out revision and ACPI HW reduced compliancy tests
125 */
126 status = acpi_get_table_with_size(ACPI_SIG_FADT, 0, &table, &tbl_size);
127 if (ACPI_FAILURE(status)) {
128 const char *msg = acpi_format_exception(status);
129
130 pr_err("Failed to get FADT table, %s\n", msg);
131 return -ENODEV;
132 }
133
134 fadt = (struct acpi_table_fadt *)table;
135
136 /*
137 * Revision in table header is the FADT Major revision, and there
138 * is a minor revision of FADT which was introduced by ACPI 5.1,
139 * we only deal with ACPI 5.1 or newer revision to get GIC and SMP
140 * boot protocol configuration data.
141 */
142 if (table->revision < 5 ||
143 (table->revision == 5 && fadt->minor_revision < 1)) {
144 pr_err(FW_BUG "Unsupported FADT revision %d.%d, should be 5.1+\n",
145 table->revision, fadt->minor_revision);
146
147 if (!fadt->arm_boot_flags) {
148 ret = -EINVAL;
149 goto out;
150 }
151 pr_err("FADT has ARM boot flags set, assuming 5.1\n");
152 }
153
154 if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) {
155 pr_err("FADT not ACPI hardware reduced compliant\n");
156 ret = -EINVAL;
157 }
158
159 out:
160 /*
161 * acpi_get_table_with_size() creates FADT table mapping that
162 * should be released after parsing and before resuming boot
163 */
164 early_acpi_os_unmap_memory(table, tbl_size);
165 return ret;
166 }
167
168 /*
169 * acpi_boot_table_init() called from setup_arch(), always.
170 * 1. find RSDP and get its address, and then find XSDT
171 * 2. extract all tables and checksums them all
172 * 3. check ACPI FADT revision
173 * 4. check ACPI FADT HW reduced flag
174 *
175 * We can parse ACPI boot-time tables such as MADT after
176 * this function is called.
177 *
178 * On return ACPI is enabled if either:
179 *
180 * - ACPI tables are initialized and sanity checks passed
181 * - acpi=force was passed in the command line and ACPI was not disabled
182 * explicitly through acpi=off command line parameter
183 *
184 * ACPI is disabled on function return otherwise
185 */
acpi_boot_table_init(void)186 void __init acpi_boot_table_init(void)
187 {
188 /*
189 * Enable ACPI instead of device tree unless
190 * - ACPI has been disabled explicitly (acpi=off), or
191 * - the device tree is not empty (it has more than just a /chosen node)
192 * and ACPI has not been force enabled (acpi=force)
193 */
194 if (param_acpi_off ||
195 (!param_acpi_force && of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
196 return;
197
198 /*
199 * ACPI is disabled at this point. Enable it in order to parse
200 * the ACPI tables and carry out sanity checks
201 */
202 enable_acpi();
203
204 /*
205 * If ACPI tables are initialized and FADT sanity checks passed,
206 * leave ACPI enabled and carry on booting; otherwise disable ACPI
207 * on initialization error.
208 * If acpi=force was passed on the command line it forces ACPI
209 * to be enabled even if its initialization failed.
210 */
211 if (acpi_table_init() || acpi_fadt_sanity_check()) {
212 pr_err("Failed to init ACPI tables\n");
213 if (!param_acpi_force)
214 disable_acpi();
215 }
216 }
217
218 #ifdef CONFIG_ACPI_APEI
arch_apei_get_mem_attribute(phys_addr_t addr)219 pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
220 {
221 /*
222 * According to "Table 8 Map: EFI memory types to AArch64 memory
223 * types" of UEFI 2.5 section 2.3.6.1, each EFI memory type is
224 * mapped to a corresponding MAIR attribute encoding.
225 * The EFI memory attribute advises all possible capabilities
226 * of a memory region. We use the most efficient capability.
227 */
228
229 u64 attr;
230
231 attr = efi_mem_attributes(addr);
232 if (attr & EFI_MEMORY_WB)
233 return PAGE_KERNEL;
234 if (attr & EFI_MEMORY_WT)
235 return __pgprot(PROT_NORMAL_WT);
236 if (attr & EFI_MEMORY_WC)
237 return __pgprot(PROT_NORMAL_NC);
238 return __pgprot(PROT_DEVICE_nGnRnE);
239 }
240 #endif
241