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 #include <linux/serial_core.h> 28 29 #include <asm/cputype.h> 30 #include <asm/cpu_ops.h> 31 #include <asm/smp_plat.h> 32 33 #ifdef CONFIG_ACPI_APEI 34 # include <linux/efi.h> 35 # include <asm/pgtable.h> 36 #endif 37 38 int acpi_noirq = 1; /* skip ACPI IRQ initialization */ 39 int acpi_disabled = 1; 40 EXPORT_SYMBOL(acpi_disabled); 41 42 int acpi_pci_disabled = 1; /* skip ACPI PCI scan and IRQ initialization */ 43 EXPORT_SYMBOL(acpi_pci_disabled); 44 45 static bool param_acpi_off __initdata; 46 static bool param_acpi_on __initdata; 47 static bool param_acpi_force __initdata; 48 49 static int __init parse_acpi(char *arg) 50 { 51 if (!arg) 52 return -EINVAL; 53 54 /* "acpi=off" disables both ACPI table parsing and interpreter */ 55 if (strcmp(arg, "off") == 0) 56 param_acpi_off = true; 57 else if (strcmp(arg, "on") == 0) /* prefer ACPI over DT */ 58 param_acpi_on = true; 59 else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */ 60 param_acpi_force = true; 61 else 62 return -EINVAL; /* Core will print when we return error */ 63 64 return 0; 65 } 66 early_param("acpi", parse_acpi); 67 68 static int __init dt_scan_depth1_nodes(unsigned long node, 69 const char *uname, int depth, 70 void *data) 71 { 72 /* 73 * Ignore anything not directly under the root node; we'll 74 * catch its parent instead. 75 */ 76 if (depth != 1) 77 return 0; 78 79 if (strcmp(uname, "chosen") == 0) 80 return 0; 81 82 if (strcmp(uname, "hypervisor") == 0 && 83 of_flat_dt_is_compatible(node, "xen,xen")) 84 return 0; 85 86 /* 87 * This node at depth 1 is neither a chosen node nor a xen node, 88 * which we do not expect. 89 */ 90 return 1; 91 } 92 93 /* 94 * __acpi_map_table() will be called before page_init(), so early_ioremap() 95 * or early_memremap() should be called here to for ACPI table mapping. 96 */ 97 char *__init __acpi_map_table(unsigned long phys, unsigned long size) 98 { 99 if (!size) 100 return NULL; 101 102 return early_memremap(phys, size); 103 } 104 105 void __init __acpi_unmap_table(char *map, unsigned long size) 106 { 107 if (!map || !size) 108 return; 109 110 early_memunmap(map, size); 111 } 112 113 bool __init acpi_psci_present(void) 114 { 115 return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_COMPLIANT; 116 } 117 118 /* Whether HVC must be used instead of SMC as the PSCI conduit */ 119 bool __init acpi_psci_use_hvc(void) 120 { 121 return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_USE_HVC; 122 } 123 124 /* 125 * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity 126 * checks on it 127 * 128 * Return 0 on success, <0 on failure 129 */ 130 static int __init acpi_fadt_sanity_check(void) 131 { 132 struct acpi_table_header *table; 133 struct acpi_table_fadt *fadt; 134 acpi_status status; 135 int ret = 0; 136 137 /* 138 * FADT is required on arm64; retrieve it to check its presence 139 * and carry out revision and ACPI HW reduced compliancy tests 140 */ 141 status = acpi_get_table(ACPI_SIG_FADT, 0, &table); 142 if (ACPI_FAILURE(status)) { 143 const char *msg = acpi_format_exception(status); 144 145 pr_err("Failed to get FADT table, %s\n", msg); 146 return -ENODEV; 147 } 148 149 fadt = (struct acpi_table_fadt *)table; 150 151 /* 152 * Revision in table header is the FADT Major revision, and there 153 * is a minor revision of FADT which was introduced by ACPI 5.1, 154 * we only deal with ACPI 5.1 or newer revision to get GIC and SMP 155 * boot protocol configuration data. 156 */ 157 if (table->revision < 5 || 158 (table->revision == 5 && fadt->minor_revision < 1)) { 159 pr_err("Unsupported FADT revision %d.%d, should be 5.1+\n", 160 table->revision, fadt->minor_revision); 161 ret = -EINVAL; 162 goto out; 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_init_is_deferred) 233 early_init_dt_scan_chosen_stdout(); 234 } else { 235 parse_spcr(earlycon_init_is_deferred); 236 } 237 } 238 239 #ifdef CONFIG_ACPI_APEI 240 pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr) 241 { 242 /* 243 * According to "Table 8 Map: EFI memory types to AArch64 memory 244 * types" of UEFI 2.5 section 2.3.6.1, each EFI memory type is 245 * mapped to a corresponding MAIR attribute encoding. 246 * The EFI memory attribute advises all possible capabilities 247 * of a memory region. We use the most efficient capability. 248 */ 249 250 u64 attr; 251 252 attr = efi_mem_attributes(addr); 253 if (attr & EFI_MEMORY_WB) 254 return PAGE_KERNEL; 255 if (attr & EFI_MEMORY_WT) 256 return __pgprot(PROT_NORMAL_WT); 257 if (attr & EFI_MEMORY_WC) 258 return __pgprot(PROT_NORMAL_NC); 259 return __pgprot(PROT_DEVICE_nGnRnE); 260 } 261 #endif 262