arch/arm64/kernel/acpi.c

   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