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