1 // SPDX-License-Identifier: GPL-2.0-only
3 * ARM64 Specific Low-Level ACPI Boot Support
5 * Copyright (C) 2013-2014, Linaro Ltd.
6 * Author: Al Stone <al.stone@linaro.org>
7 * Author: Graeme Gregory <graeme.gregory@linaro.org>
8 * Author: Hanjun Guo <hanjun.guo@linaro.org>
9 * Author: Tomasz Nowicki <tomasz.nowicki@linaro.org>
10 * Author: Naresh Bhat <naresh.bhat@linaro.org>
13 #define pr_fmt(fmt) "ACPI: " fmt
15 #include <linux/acpi.h>
16 #include <linux/arm-smccc.h>
17 #include <linux/cpumask.h>
18 #include <linux/efi.h>
19 #include <linux/efi-bgrt.h>
20 #include <linux/init.h>
21 #include <linux/irq.h>
22 #include <linux/irqdomain.h>
23 #include <linux/irq_work.h>
24 #include <linux/memblock.h>
25 #include <linux/of_fdt.h>
26 #include <linux/libfdt.h>
27 #include <linux/smp.h>
28 #include <linux/serial_core.h>
29 #include <linux/suspend.h>
30 #include <linux/pgtable.h>
32 #include <acpi/ghes.h>
33 #include <acpi/processor.h>
34 #include <asm/cputype.h>
35 #include <asm/cpu_ops.h>
36 #include <asm/daifflags.h>
37 #include <asm/smp_plat.h>
39 int acpi_noirq
= 1; /* skip ACPI IRQ initialization */
40 int acpi_disabled
= 1;
41 EXPORT_SYMBOL(acpi_disabled
);
43 int acpi_pci_disabled
= 1; /* skip ACPI PCI scan and IRQ initialization */
44 EXPORT_SYMBOL(acpi_pci_disabled
);
46 static bool param_acpi_off __initdata
;
47 static bool param_acpi_on __initdata
;
48 static bool param_acpi_force __initdata
;
49 static bool param_acpi_nospcr __initdata
;
51 static int __init
parse_acpi(char *arg
)
56 /* "acpi=off" disables both ACPI table parsing and interpreter */
57 if (strcmp(arg
, "off") == 0)
58 param_acpi_off
= true;
59 else if (strcmp(arg
, "on") == 0) /* prefer ACPI over DT */
61 else if (strcmp(arg
, "force") == 0) /* force ACPI to be enabled */
62 param_acpi_force
= true;
63 else if (strcmp(arg
, "nospcr") == 0) /* disable SPCR as default console */
64 param_acpi_nospcr
= true;
66 return -EINVAL
; /* Core will print when we return error */
70 early_param("acpi", parse_acpi
);
72 static bool __init
dt_is_stub(void)
76 fdt_for_each_subnode(node
, initial_boot_params
, 0) {
77 const char *name
= fdt_get_name(initial_boot_params
, node
, NULL
);
78 if (strcmp(name
, "chosen") == 0)
80 if (strcmp(name
, "hypervisor") == 0 &&
81 of_flat_dt_is_compatible(node
, "xen,xen"))
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.
94 void __init __iomem
*__acpi_map_table(unsigned long phys
, unsigned long size
)
99 return early_memremap(phys
, size
);
102 void __init
__acpi_unmap_table(void __iomem
*map
, unsigned long size
)
107 early_memunmap(map
, size
);
110 bool __init
acpi_psci_present(void)
112 return acpi_gbl_FADT
.arm_boot_flags
& ACPI_FADT_PSCI_COMPLIANT
;
115 /* Whether HVC must be used instead of SMC as the PSCI conduit */
116 bool acpi_psci_use_hvc(void)
118 return acpi_gbl_FADT
.arm_boot_flags
& ACPI_FADT_PSCI_USE_HVC
;
122 * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity
125 * Return 0 on success, <0 on failure
127 static int __init
acpi_fadt_sanity_check(void)
129 struct acpi_table_header
*table
;
130 struct acpi_table_fadt
*fadt
;
135 * FADT is required on arm64; retrieve it to check its presence
136 * and carry out revision and ACPI HW reduced compliancy tests
138 status
= acpi_get_table(ACPI_SIG_FADT
, 0, &table
);
139 if (ACPI_FAILURE(status
)) {
140 const char *msg
= acpi_format_exception(status
);
142 pr_err("Failed to get FADT table, %s\n", msg
);
146 fadt
= (struct acpi_table_fadt
*)table
;
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.
154 if (table
->revision
< 5 ||
155 (table
->revision
== 5 && fadt
->minor_revision
< 1)) {
156 pr_err(FW_BUG
"Unsupported FADT revision %d.%d, should be 5.1+\n",
157 table
->revision
, fadt
->minor_revision
);
159 if (!fadt
->arm_boot_flags
) {
163 pr_err("FADT has ARM boot flags set, assuming 5.1\n");
166 if (!(fadt
->flags
& ACPI_FADT_HW_REDUCED
)) {
167 pr_err("FADT not ACPI hardware reduced compliant\n");
173 * acpi_get_table() creates FADT table mapping that
174 * should be released after parsing and before resuming boot
176 acpi_put_table(table
);
181 * acpi_boot_table_init() called from setup_arch(), always.
182 * 1. find RSDP and get its address, and then find XSDT
183 * 2. extract all tables and checksums them all
184 * 3. check ACPI FADT revision
185 * 4. check ACPI FADT HW reduced flag
187 * We can parse ACPI boot-time tables such as MADT after
188 * this function is called.
190 * On return ACPI is enabled if either:
192 * - ACPI tables are initialized and sanity checks passed
193 * - acpi=force was passed in the command line and ACPI was not disabled
194 * explicitly through acpi=off command line parameter
196 * ACPI is disabled on function return otherwise
198 void __init
acpi_boot_table_init(void)
201 * Enable ACPI instead of device tree unless
202 * - ACPI has been disabled explicitly (acpi=off), or
203 * - the device tree is not empty (it has more than just a /chosen node,
204 * and a /hypervisor node when running on Xen)
205 * and ACPI has not been [force] enabled (acpi=on|force)
207 if (param_acpi_off
||
208 (!param_acpi_on
&& !param_acpi_force
&& !dt_is_stub()))
212 * ACPI is disabled at this point. Enable it in order to parse
213 * the ACPI tables and carry out sanity checks
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.
224 if (acpi_table_init() || acpi_fadt_sanity_check()) {
225 pr_err("Failed to init ACPI tables\n");
226 if (!param_acpi_force
)
232 if (earlycon_acpi_spcr_enable
)
233 early_init_dt_scan_chosen_stdout();
235 #ifdef CONFIG_HIBERNATION
236 struct acpi_table_header
*facs
= NULL
;
237 acpi_get_table(ACPI_SIG_FACS
, 1, &facs
);
239 swsusp_hardware_signature
=
240 ((struct acpi_table_facs
*)facs
)->hardware_signature
;
241 acpi_put_table(facs
);
246 * For varying privacy and security reasons, sometimes need
247 * to completely silence the serial console output, and only
248 * enable it when needed.
249 * But there are many existing systems that depend on this
250 * behaviour, use acpi=nospcr to disable console in ACPI SPCR
251 * table as default serial console.
253 acpi_parse_spcr(earlycon_acpi_spcr_enable
,
255 pr_info("Use ACPI SPCR as default console: %s\n",
256 param_acpi_nospcr
? "No" : "Yes");
258 if (IS_ENABLED(CONFIG_ACPI_BGRT
))
259 acpi_table_parse(ACPI_SIG_BGRT
, acpi_parse_bgrt
);
263 static pgprot_t
__acpi_get_writethrough_mem_attribute(void)
266 * Although UEFI specifies the use of Normal Write-through for
267 * EFI_MEMORY_WT, it is seldom used in practice and not implemented
268 * by most (all?) CPUs. Rather than allocate a MAIR just for this
269 * purpose, emit a warning and use Normal Non-cacheable instead.
271 pr_warn_once("No MAIR allocation for EFI_MEMORY_WT; treating as Normal Non-cacheable\n");
272 return __pgprot(PROT_NORMAL_NC
);
275 pgprot_t
__acpi_get_mem_attribute(phys_addr_t addr
)
278 * According to "Table 8 Map: EFI memory types to AArch64 memory
279 * types" of UEFI 2.5 section 2.3.6.1, each EFI memory type is
280 * mapped to a corresponding MAIR attribute encoding.
281 * The EFI memory attribute advises all possible capabilities
282 * of a memory region.
287 attr
= efi_mem_attributes(addr
);
288 if (attr
& EFI_MEMORY_WB
)
290 if (attr
& EFI_MEMORY_WC
)
291 return __pgprot(PROT_NORMAL_NC
);
292 if (attr
& EFI_MEMORY_WT
)
293 return __acpi_get_writethrough_mem_attribute();
294 return __pgprot(PROT_DEVICE_nGnRnE
);
297 void __iomem
*acpi_os_ioremap(acpi_physical_address phys
, acpi_size size
)
299 efi_memory_desc_t
*md
, *region
= NULL
;
302 if (WARN_ON_ONCE(!efi_enabled(EFI_MEMMAP
)))
305 for_each_efi_memory_desc(md
) {
306 u64 end
= md
->phys_addr
+ (md
->num_pages
<< EFI_PAGE_SHIFT
);
308 if (phys
< md
->phys_addr
|| phys
>= end
)
311 if (phys
+ size
> end
) {
312 pr_warn(FW_BUG
"requested region covers multiple EFI memory regions\n");
320 * It is fine for AML to remap regions that are not represented in the
321 * EFI memory map at all, as it only describes normal memory, and MMIO
322 * regions that require a virtual mapping to make them accessible to
323 * the EFI runtime services.
325 prot
= __pgprot(PROT_DEVICE_nGnRnE
);
327 switch (region
->type
) {
328 case EFI_LOADER_CODE
:
329 case EFI_LOADER_DATA
:
330 case EFI_BOOT_SERVICES_CODE
:
331 case EFI_BOOT_SERVICES_DATA
:
332 case EFI_CONVENTIONAL_MEMORY
:
333 case EFI_PERSISTENT_MEMORY
:
334 if (memblock_is_map_memory(phys
) ||
335 !memblock_is_region_memory(phys
, size
)) {
336 pr_warn(FW_BUG
"requested region covers kernel memory @ %pa\n", &phys
);
340 * Mapping kernel memory is permitted if the region in
341 * question is covered by a single memblock with the
342 * NOMAP attribute set: this enables the use of ACPI
343 * table overrides passed via initramfs, which are
344 * reserved in memory using arch_reserve_mem_area()
345 * below. As this particular use case only requires
346 * read access, fall through to the R/O mapping case.
350 case EFI_RUNTIME_SERVICES_CODE
:
352 * This would be unusual, but not problematic per se,
353 * as long as we take care not to create a writable
354 * mapping for executable code.
356 prot
= PAGE_KERNEL_RO
;
359 case EFI_ACPI_RECLAIM_MEMORY
:
361 * ACPI reclaim memory is used to pass firmware tables
362 * and other data that is intended for consumption by
363 * the OS only, which may decide it wants to reclaim
364 * that memory and use it for something else. We never
365 * do that, but we usually add it to the linear map
366 * anyway, in which case we should use the existing
369 if (memblock_is_map_memory(phys
))
370 return (void __iomem
*)__phys_to_virt(phys
);
374 if (region
->attribute
& EFI_MEMORY_WB
)
376 else if (region
->attribute
& EFI_MEMORY_WC
)
377 prot
= __pgprot(PROT_NORMAL_NC
);
378 else if (region
->attribute
& EFI_MEMORY_WT
)
379 prot
= __acpi_get_writethrough_mem_attribute();
382 return ioremap_prot(phys
, size
, pgprot_val(prot
));
386 * Claim Synchronous External Aborts as a firmware first notification.
388 * Used by KVM and the arch do_sea handler.
389 * @regs may be NULL when called from process context.
391 int apei_claim_sea(struct pt_regs
*regs
)
394 bool return_to_irqs_enabled
;
395 unsigned long current_flags
;
397 if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES
))
400 current_flags
= local_daif_save_flags();
402 /* current_flags isn't useful here as daif doesn't tell us about pNMI */
403 return_to_irqs_enabled
= !irqs_disabled_flags(arch_local_save_flags());
406 return_to_irqs_enabled
= interrupts_enabled(regs
);
409 * SEA can interrupt SError, mask it and describe this as an NMI so
410 * that APEI defers the handling.
412 local_daif_restore(DAIF_ERRCTX
);
414 err
= ghes_notify_sea();
418 * APEI NMI-like notifications are deferred to irq_work. Unless
419 * we interrupted irqs-masked code, we can do that now.
422 if (return_to_irqs_enabled
) {
423 local_daif_restore(DAIF_PROCCTX_NOIRQ
);
428 pr_warn_ratelimited("APEI work queued but not completed");
433 local_daif_restore(current_flags
);
438 void arch_reserve_mem_area(acpi_physical_address addr
, size_t size
)
440 memblock_mark_nomap(addr
, size
);
443 #ifdef CONFIG_ACPI_HOTPLUG_CPU
444 int acpi_map_cpu(acpi_handle handle
, phys_cpuid_t physid
, u32 apci_id
,
447 /* If an error code is passed in this stub can't fix it */
449 pr_warn_once("Unable to map CPU to valid ID\n");
455 EXPORT_SYMBOL(acpi_map_cpu
);
457 int acpi_unmap_cpu(int cpu
)
461 EXPORT_SYMBOL(acpi_unmap_cpu
);
462 #endif /* CONFIG_ACPI_HOTPLUG_CPU */