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/cpumask.h> 20 #include <linux/efi.h> 21 #include <linux/efi-bgrt.h> 22 #include <linux/init.h> 23 #include <linux/irq.h> 24 #include <linux/irqdomain.h> 25 #include <linux/memblock.h> 26 #include <linux/of_fdt.h> 27 #include <linux/smp.h> 28 #include <linux/serial_core.h> 29 30 #include <acpi/ghes.h> 31 #include <asm/cputype.h> 32 #include <asm/cpu_ops.h> 33 #include <asm/daifflags.h> 34 #include <asm/pgtable.h> 35 #include <asm/smp_plat.h> 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_on __initdata; 46 static bool param_acpi_force __initdata; 47 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, "on") == 0) /* prefer ACPI over DT */ 57 param_acpi_on = true; 58 else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */ 59 param_acpi_force = true; 60 else 61 return -EINVAL; /* Core will print when we return error */ 62 63 return 0; 64 } 65 early_param("acpi", parse_acpi); 66 67 static int __init dt_scan_depth1_nodes(unsigned long node, 68 const char *uname, int depth, 69 void *data) 70 { 71 /* 72 * Ignore anything not directly under the root node; we'll 73 * catch its parent instead. 74 */ 75 if (depth != 1) 76 return 0; 77 78 if (strcmp(uname, "chosen") == 0) 79 return 0; 80 81 if (strcmp(uname, "hypervisor") == 0 && 82 of_flat_dt_is_compatible(node, "xen,xen")) 83 return 0; 84 85 /* 86 * This node at depth 1 is neither a chosen node nor a xen node, 87 * which we do not expect. 88 */ 89 return 1; 90 } 91 92 /* 93 * __acpi_map_table() will be called before page_init(), so early_ioremap() 94 * or early_memremap() should be called here to for ACPI table mapping. 95 */ 96 void __init __iomem *__acpi_map_table(unsigned long phys, unsigned long size) 97 { 98 if (!size) 99 return NULL; 100 101 return early_memremap(phys, size); 102 } 103 104 void __init __acpi_unmap_table(void __iomem *map, unsigned long size) 105 { 106 if (!map || !size) 107 return; 108 109 early_memunmap(map, size); 110 } 111 112 bool __init acpi_psci_present(void) 113 { 114 return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_COMPLIANT; 115 } 116 117 /* Whether HVC must be used instead of SMC as the PSCI conduit */ 118 bool acpi_psci_use_hvc(void) 119 { 120 return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_USE_HVC; 121 } 122 123 /* 124 * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity 125 * checks on it 126 * 127 * Return 0 on success, <0 on failure 128 */ 129 static int __init acpi_fadt_sanity_check(void) 130 { 131 struct acpi_table_header *table; 132 struct acpi_table_fadt *fadt; 133 acpi_status status; 134 int ret = 0; 135 136 /* 137 * FADT is required on arm64; retrieve it to check its presence 138 * and carry out revision and ACPI HW reduced compliancy tests 139 */ 140 status = acpi_get_table(ACPI_SIG_FADT, 0, &table); 141 if (ACPI_FAILURE(status)) { 142 const char *msg = acpi_format_exception(status); 143 144 pr_err("Failed to get FADT table, %s\n", msg); 145 return -ENODEV; 146 } 147 148 fadt = (struct acpi_table_fadt *)table; 149 150 /* 151 * Revision in table header is the FADT Major revision, and there 152 * is a minor revision of FADT which was introduced by ACPI 5.1, 153 * we only deal with ACPI 5.1 or newer revision to get GIC and SMP 154 * boot protocol configuration data. 155 */ 156 if (table->revision < 5 || 157 (table->revision == 5 && fadt->minor_revision < 1)) { 158 pr_err("Unsupported FADT revision %d.%d, should be 5.1+\n", 159 table->revision, fadt->minor_revision); 160 ret = -EINVAL; 161 goto out; 162 } 163 164 if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) { 165 pr_err("FADT not ACPI hardware reduced compliant\n"); 166 ret = -EINVAL; 167 } 168 169 out: 170 /* 171 * acpi_get_table() creates FADT table mapping that 172 * should be released after parsing and before resuming boot 173 */ 174 acpi_put_table(table); 175 return ret; 176 } 177 178 /* 179 * acpi_boot_table_init() called from setup_arch(), always. 180 * 1. find RSDP and get its address, and then find XSDT 181 * 2. extract all tables and checksums them all 182 * 3. check ACPI FADT revision 183 * 4. check ACPI FADT HW reduced flag 184 * 185 * We can parse ACPI boot-time tables such as MADT after 186 * this function is called. 187 * 188 * On return ACPI is enabled if either: 189 * 190 * - ACPI tables are initialized and sanity checks passed 191 * - acpi=force was passed in the command line and ACPI was not disabled 192 * explicitly through acpi=off command line parameter 193 * 194 * ACPI is disabled on function return otherwise 195 */ 196 void __init acpi_boot_table_init(void) 197 { 198 /* 199 * Enable ACPI instead of device tree unless 200 * - ACPI has been disabled explicitly (acpi=off), or 201 * - the device tree is not empty (it has more than just a /chosen node, 202 * and a /hypervisor node when running on Xen) 203 * and ACPI has not been [force] enabled (acpi=on|force) 204 */ 205 if (param_acpi_off || 206 (!param_acpi_on && !param_acpi_force && 207 of_scan_flat_dt(dt_scan_depth1_nodes, NULL))) 208 goto done; 209 210 /* 211 * ACPI is disabled at this point. Enable it in order to parse 212 * the ACPI tables and carry out sanity checks 213 */ 214 enable_acpi(); 215 216 /* 217 * If ACPI tables are initialized and FADT sanity checks passed, 218 * leave ACPI enabled and carry on booting; otherwise disable ACPI 219 * on initialization error. 220 * If acpi=force was passed on the command line it forces ACPI 221 * to be enabled even if its initialization failed. 222 */ 223 if (acpi_table_init() || acpi_fadt_sanity_check()) { 224 pr_err("Failed to init ACPI tables\n"); 225 if (!param_acpi_force) 226 disable_acpi(); 227 } 228 229 done: 230 if (acpi_disabled) { 231 if (earlycon_acpi_spcr_enable) 232 early_init_dt_scan_chosen_stdout(); 233 } else { 234 acpi_parse_spcr(earlycon_acpi_spcr_enable, true); 235 if (IS_ENABLED(CONFIG_ACPI_BGRT)) 236 acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt); 237 } 238 } 239 240 pgprot_t __acpi_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 } 261 262 /* 263 * Claim Synchronous External Aborts as a firmware first notification. 264 * 265 * Used by KVM and the arch do_sea handler. 266 * @regs may be NULL when called from process context. 267 */ 268 int apei_claim_sea(struct pt_regs *regs) 269 { 270 int err = -ENOENT; 271 unsigned long current_flags; 272 273 if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES)) 274 return err; 275 276 current_flags = arch_local_save_flags(); 277 278 /* 279 * SEA can interrupt SError, mask it and describe this as an NMI so 280 * that APEI defers the handling. 281 */ 282 local_daif_restore(DAIF_ERRCTX); 283 nmi_enter(); 284 err = ghes_notify_sea(); 285 nmi_exit(); 286 local_daif_restore(current_flags); 287 288 return err; 289 } 290