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 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 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 */ 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 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 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 */ 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 */ 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("Unsupported FADT revision %d.%d, should be 5.1+\n", 145 table->revision, fadt->minor_revision); 146 ret = -EINVAL; 147 goto out; 148 } 149 150 if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) { 151 pr_err("FADT not ACPI hardware reduced compliant\n"); 152 ret = -EINVAL; 153 } 154 155 out: 156 /* 157 * acpi_get_table_with_size() creates FADT table mapping that 158 * should be released after parsing and before resuming boot 159 */ 160 early_acpi_os_unmap_memory(table, tbl_size); 161 return ret; 162 } 163 164 /* 165 * acpi_boot_table_init() called from setup_arch(), always. 166 * 1. find RSDP and get its address, and then find XSDT 167 * 2. extract all tables and checksums them all 168 * 3. check ACPI FADT revision 169 * 4. check ACPI FADT HW reduced flag 170 * 171 * We can parse ACPI boot-time tables such as MADT after 172 * this function is called. 173 * 174 * On return ACPI is enabled if either: 175 * 176 * - ACPI tables are initialized and sanity checks passed 177 * - acpi=force was passed in the command line and ACPI was not disabled 178 * explicitly through acpi=off command line parameter 179 * 180 * ACPI is disabled on function return otherwise 181 */ 182 void __init acpi_boot_table_init(void) 183 { 184 /* 185 * Enable ACPI instead of device tree unless 186 * - ACPI has been disabled explicitly (acpi=off), or 187 * - the device tree is not empty (it has more than just a /chosen node) 188 * and ACPI has not been force enabled (acpi=force) 189 */ 190 if (param_acpi_off || 191 (!param_acpi_force && of_scan_flat_dt(dt_scan_depth1_nodes, NULL))) 192 return; 193 194 /* 195 * ACPI is disabled at this point. Enable it in order to parse 196 * the ACPI tables and carry out sanity checks 197 */ 198 enable_acpi(); 199 200 /* 201 * If ACPI tables are initialized and FADT sanity checks passed, 202 * leave ACPI enabled and carry on booting; otherwise disable ACPI 203 * on initialization error. 204 * If acpi=force was passed on the command line it forces ACPI 205 * to be enabled even if its initialization failed. 206 */ 207 if (acpi_table_init() || acpi_fadt_sanity_check()) { 208 pr_err("Failed to init ACPI tables\n"); 209 if (!param_acpi_force) 210 disable_acpi(); 211 } 212 } 213 214 #ifdef CONFIG_ACPI_APEI 215 pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr) 216 { 217 /* 218 * According to "Table 8 Map: EFI memory types to AArch64 memory 219 * types" of UEFI 2.5 section 2.3.6.1, each EFI memory type is 220 * mapped to a corresponding MAIR attribute encoding. 221 * The EFI memory attribute advises all possible capabilities 222 * of a memory region. We use the most efficient capability. 223 */ 224 225 u64 attr; 226 227 attr = efi_mem_attributes(addr); 228 if (attr & EFI_MEMORY_WB) 229 return PAGE_KERNEL; 230 if (attr & EFI_MEMORY_WT) 231 return __pgprot(PROT_NORMAL_WT); 232 if (attr & EFI_MEMORY_WC) 233 return __pgprot(PROT_NORMAL_NC); 234 return __pgprot(PROT_DEVICE_nGnRnE); 235 } 236 #endif 237