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-rw-r--r--Documentation/kernel-parameters.txt3
-rw-r--r--arch/arm64/Kconfig2
-rw-r--r--arch/arm64/include/asm/acpi.h15
-rw-r--r--arch/arm64/kernel/acpi.c11
-rw-r--r--arch/x86/kernel/acpi/apei.c3
-rw-r--r--drivers/acpi/Kconfig3
-rw-r--r--drivers/acpi/Makefile1
-rw-r--r--drivers/acpi/apei/Kconfig1
-rw-r--r--drivers/acpi/apei/Makefile2
-rw-r--r--drivers/acpi/apei/apei-internal.h2
-rw-r--r--drivers/acpi/apei/bert.c150
-rw-r--r--drivers/acpi/apei/hest.c18
-rw-r--r--drivers/acpi/pci_root.c2
-rw-r--r--drivers/acpi/scan.c3
-rw-r--r--drivers/acpi/spcr.c111
-rw-r--r--drivers/of/fdt.c11
-rw-r--r--drivers/tty/serial/amba-pl011.c56
-rw-r--r--drivers/tty/serial/earlycon.c19
-rw-r--r--include/linux/acpi.h6
-rw-r--r--include/linux/of_fdt.h2
-rw-r--r--include/linux/serial_core.h6
21 files changed, 403 insertions, 24 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 82b42c958d1c..f565259167d7 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -582,6 +582,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
bootmem_debug [KNL] Enable bootmem allocator debug messages.
+ bert_disable [ACPI]
+ Disable BERT OS support on buggy BIOSes.
+
bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
bttv.radio= Most important insmod options are available as
kernel args too.
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 5a0a691d4220..e167260fcd0c 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -3,6 +3,8 @@ config ARM64
select ACPI_CCA_REQUIRED if ACPI
select ACPI_GENERIC_GSI if ACPI
select ACPI_REDUCED_HARDWARE_ONLY if ACPI
+ select ACPI_SPCR_TABLE if ACPI
+ select HAVE_ACPI_APEI if ACPI
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
select ARCH_HAS_ELF_RANDOMIZE
diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
index aee323b13802..4a6c959995cc 100644
--- a/arch/arm64/include/asm/acpi.h
+++ b/arch/arm64/include/asm/acpi.h
@@ -17,6 +17,7 @@
#include <asm/cputype.h>
#include <asm/smp_plat.h>
+#include <asm/tlbflush.h>
/* Macros for consistency checks of the GICC subtable of MADT */
#define ACPI_MADT_GICC_LENGTH \
@@ -110,7 +111,19 @@ static inline const char *acpi_get_enable_method(int cpu)
}
#ifdef CONFIG_ACPI_APEI
+#define acpi_disable_cmcff 1
pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr);
-#endif
+/*
+ * This inline function is used in IRQ context (by GHES driver now),
+ * see ghes_iounmap_irq and ghes_iounmap_nmi in drivers/acpi/apei/ghes.c.
+ * The page mapped is reserved for firmware in kernel. This invalidate TLB
+ * maintenance should be broadcasted safely to make sure that all the cores
+ * will do TLB invalidation, then get the right pages.
+ */
+static inline void arch_apei_flush_tlb_one(unsigned long addr)
+{
+ flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+}
+#endif /* CONFIG_ACPI_APEI */
#endif /*_ASM_ACPI_H*/
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index 3e4f1a45b125..252a6d9c1da5 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c
@@ -24,6 +24,7 @@
#include <linux/memblock.h>
#include <linux/of_fdt.h>
#include <linux/smp.h>
+#include <linux/serial_core.h>
#include <asm/cputype.h>
#include <asm/cpu_ops.h>
@@ -206,7 +207,7 @@ void __init acpi_boot_table_init(void)
if (param_acpi_off ||
(!param_acpi_on && !param_acpi_force &&
of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
- return;
+ goto done;
/*
* ACPI is disabled at this point. Enable it in order to parse
@@ -226,6 +227,14 @@ void __init acpi_boot_table_init(void)
if (!param_acpi_force)
disable_acpi();
}
+
+done:
+ if (acpi_disabled) {
+ if (earlycon_init_is_deferred)
+ early_init_dt_scan_chosen_stdout();
+ } else {
+ parse_spcr(earlycon_init_is_deferred);
+ }
}
#ifdef CONFIG_ACPI_APEI
diff --git a/arch/x86/kernel/acpi/apei.c b/arch/x86/kernel/acpi/apei.c
index c280df6b2aa2..ea3046e0b0cf 100644
--- a/arch/x86/kernel/acpi/apei.c
+++ b/arch/x86/kernel/acpi/apei.c
@@ -24,9 +24,6 @@ int arch_apei_enable_cmcff(struct acpi_hest_header *hest_hdr, void *data)
struct acpi_hest_ia_corrected *cmc;
struct acpi_hest_ia_error_bank *mc_bank;
- if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK)
- return 0;
-
cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
if (!cmc->enabled)
return 0;
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index b7e2e776397d..89218ea0e00b 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -77,6 +77,9 @@ config ACPI_DEBUGGER_USER
endif
+config ACPI_SPCR_TABLE
+ bool
+
config ACPI_SLEEP
bool
depends on SUSPEND || HIBERNATION
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 251ce85a66fb..43cde68b00dc 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -81,6 +81,7 @@ obj-$(CONFIG_ACPI_EC_DEBUGFS) += ec_sys.o
obj-$(CONFIG_ACPI_CUSTOM_METHOD)+= custom_method.o
obj-$(CONFIG_ACPI_BGRT) += bgrt.o
obj-$(CONFIG_ACPI_CPPC_LIB) += cppc_acpi.o
+obj-$(CONFIG_ACPI_SPCR_TABLE) += spcr.o
obj-$(CONFIG_ACPI_DEBUGGER_USER) += acpi_dbg.o
# processor has its own "processor." module_param namespace
diff --git a/drivers/acpi/apei/Kconfig b/drivers/acpi/apei/Kconfig
index b0140c8fc733..b037c5c6db97 100644
--- a/drivers/acpi/apei/Kconfig
+++ b/drivers/acpi/apei/Kconfig
@@ -8,6 +8,7 @@ config ACPI_APEI
bool "ACPI Platform Error Interface (APEI)"
select MISC_FILESYSTEMS
select PSTORE
+ select EFI if ARM64
select UEFI_CPER
depends on HAVE_ACPI_APEI
help
diff --git a/drivers/acpi/apei/Makefile b/drivers/acpi/apei/Makefile
index 5d575a955940..e50573de25f1 100644
--- a/drivers/acpi/apei/Makefile
+++ b/drivers/acpi/apei/Makefile
@@ -3,4 +3,4 @@ obj-$(CONFIG_ACPI_APEI_GHES) += ghes.o
obj-$(CONFIG_ACPI_APEI_EINJ) += einj.o
obj-$(CONFIG_ACPI_APEI_ERST_DEBUG) += erst-dbg.o
-apei-y := apei-base.o hest.o erst.o
+apei-y := apei-base.o hest.o erst.o bert.o
diff --git a/drivers/acpi/apei/apei-internal.h b/drivers/acpi/apei/apei-internal.h
index 16129c78b489..6e9f14c0a71b 100644
--- a/drivers/acpi/apei/apei-internal.h
+++ b/drivers/acpi/apei/apei-internal.h
@@ -1,6 +1,6 @@
/*
* apei-internal.h - ACPI Platform Error Interface internal
- * definations.
+ * definitions.
*/
#ifndef APEI_INTERNAL_H
diff --git a/drivers/acpi/apei/bert.c b/drivers/acpi/apei/bert.c
new file mode 100644
index 000000000000..a05b5c0cf181
--- /dev/null
+++ b/drivers/acpi/apei/bert.c
@@ -0,0 +1,150 @@
+/*
+ * APEI Boot Error Record Table (BERT) support
+ *
+ * Copyright 2011 Intel Corp.
+ * Author: Huang Ying <ying.huang@intel.com>
+ *
+ * Under normal circumstances, when a hardware error occurs, the error
+ * handler receives control and processes the error. This gives OSPM a
+ * chance to process the error condition, report it, and optionally attempt
+ * recovery. In some cases, the system is unable to process an error.
+ * For example, system firmware or a management controller may choose to
+ * reset the system or the system might experience an uncontrolled crash
+ * or reset.The boot error source is used to report unhandled errors that
+ * occurred in a previous boot. This mechanism is described in the BERT
+ * table.
+ *
+ * For more information about BERT, please refer to ACPI Specification
+ * version 4.0, section 17.3.1
+ *
+ * This file is licensed under GPLv2.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/io.h>
+
+#include "apei-internal.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) "BERT: " fmt
+
+static int bert_disable;
+
+static void __init bert_print_all(struct acpi_bert_region *region,
+ unsigned int region_len)
+{
+ struct acpi_hest_generic_status *estatus =
+ (struct acpi_hest_generic_status *)region;
+ int remain = region_len;
+ u32 estatus_len;
+
+ if (!estatus->block_status)
+ return;
+
+ while (remain > sizeof(struct acpi_bert_region)) {
+ if (cper_estatus_check(estatus)) {
+ pr_err(FW_BUG "Invalid error record.\n");
+ return;
+ }
+
+ estatus_len = cper_estatus_len(estatus);
+ if (remain < estatus_len) {
+ pr_err(FW_BUG "Truncated status block (length: %u).\n",
+ estatus_len);
+ return;
+ }
+
+ pr_info_once("Error records from previous boot:\n");
+
+ cper_estatus_print(KERN_INFO HW_ERR, estatus);
+
+ /*
+ * Because the boot error source is "one-time polled" type,
+ * clear Block Status of current Generic Error Status Block,
+ * once it's printed.
+ */
+ estatus->block_status = 0;
+
+ estatus = (void *)estatus + estatus_len;
+ /* No more error records. */
+ if (!estatus->block_status)
+ return;
+
+ remain -= estatus_len;
+ }
+}
+
+static int __init setup_bert_disable(char *str)
+{
+ bert_disable = 1;
+
+ return 0;
+}
+__setup("bert_disable", setup_bert_disable);
+
+static int __init bert_check_table(struct acpi_table_bert *bert_tab)
+{
+ if (bert_tab->header.length < sizeof(struct acpi_table_bert) ||
+ bert_tab->region_length < sizeof(struct acpi_bert_region))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int __init bert_init(void)
+{
+ struct acpi_bert_region *boot_error_region;
+ struct acpi_table_bert *bert_tab;
+ unsigned int region_len;
+ acpi_status status;
+ int rc = 0;
+
+ if (acpi_disabled)
+ return 0;
+
+ if (bert_disable) {
+ pr_info("Boot Error Record Table support is disabled.\n");
+ return 0;
+ }
+
+ status = acpi_get_table(ACPI_SIG_BERT, 0, (struct acpi_table_header **)&bert_tab);
+ if (status == AE_NOT_FOUND)
+ return 0;
+
+ if (ACPI_FAILURE(status)) {
+ pr_err("get table failed, %s.\n", acpi_format_exception(status));
+ return -EINVAL;
+ }
+
+ rc = bert_check_table(bert_tab);
+ if (rc) {
+ pr_err(FW_BUG "table invalid.\n");
+ return rc;
+ }
+
+ region_len = bert_tab->region_length;
+ if (!request_mem_region(bert_tab->address, region_len, "APEI BERT")) {
+ pr_err("Can't request iomem region <%016llx-%016llx>.\n",
+ (unsigned long long)bert_tab->address,
+ (unsigned long long)bert_tab->address + region_len - 1);
+ return -EIO;
+ }
+
+ boot_error_region = ioremap_cache(bert_tab->address, region_len);
+ if (boot_error_region) {
+ bert_print_all(boot_error_region, region_len);
+ iounmap(boot_error_region);
+ } else {
+ rc = -ENOMEM;
+ }
+
+ release_mem_region(bert_tab->address, region_len);
+
+ return rc;
+}
+
+late_initcall(bert_init);
diff --git a/drivers/acpi/apei/hest.c b/drivers/acpi/apei/hest.c
index 20b3fcf4007c..792a0d988d13 100644
--- a/drivers/acpi/apei/hest.c
+++ b/drivers/acpi/apei/hest.c
@@ -123,7 +123,18 @@ EXPORT_SYMBOL_GPL(apei_hest_parse);
*/
static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data)
{
- return arch_apei_enable_cmcff(hest_hdr, data);
+ if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK)
+ return 0;
+
+ if (!acpi_disable_cmcff)
+ return !arch_apei_enable_cmcff(hest_hdr, data);
+
+ return 0;
+}
+
+static inline int __init hest_ia32_init(void)
+{
+ return apei_hest_parse(hest_parse_cmc, NULL);
}
struct ghes_arr {
@@ -232,8 +243,9 @@ void __init acpi_hest_init(void)
goto err;
}
- if (!acpi_disable_cmcff)
- apei_hest_parse(hest_parse_cmc, NULL);
+ rc = hest_ia32_init();
+ if (rc)
+ goto err;
if (!ghes_disable) {
rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index ae3fe4e64203..a35dd237ded9 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -33,7 +33,6 @@
#include <linux/acpi.h>
#include <linux/slab.h>
#include <linux/dmi.h>
-#include <acpi/apei.h> /* for acpi_hest_init() */
#include "internal.h"
@@ -865,7 +864,6 @@ out_release_info:
void __init acpi_pci_root_init(void)
{
- acpi_hest_init();
if (acpi_pci_disabled)
return;
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 5f28cf778349..e51dab7ebd6a 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -13,6 +13,8 @@
#include <linux/nls.h>
#include <linux/dma-mapping.h>
+#include <acpi/apei.h> /* for acpi_hest_init() */
+
#include <asm/pgtable.h>
#include "internal.h"
@@ -1920,6 +1922,7 @@ int __init acpi_scan_init(void)
{
int result;
+ acpi_hest_init();
acpi_pci_root_init();
acpi_pci_link_init();
acpi_processor_init();
diff --git a/drivers/acpi/spcr.c b/drivers/acpi/spcr.c
new file mode 100644
index 000000000000..f4cfc5ca78d1
--- /dev/null
+++ b/drivers/acpi/spcr.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2012, Intel Corporation
+ * Copyright (c) 2015, Red Hat, Inc.
+ * Copyright (c) 2015, 2016 Linaro Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#define pr_fmt(fmt) "ACPI: SPCR: " fmt
+
+#include <linux/acpi.h>
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/serial_core.h>
+
+/**
+ * parse_spcr() - parse ACPI SPCR table and add preferred console
+ *
+ * @earlycon: set up earlycon for the console specified by the table
+ *
+ * For the architectures with support for ACPI, CONFIG_ACPI_SPCR_TABLE may be
+ * defined to parse ACPI SPCR table. As a result of the parsing preferred
+ * console is registered and if @earlycon is true, earlycon is set up.
+ *
+ * When CONFIG_ACPI_SPCR_TABLE is defined, this function should be called
+ * from arch inintialization code as soon as the DT/ACPI decision is made.
+ *
+ */
+int __init parse_spcr(bool earlycon)
+{
+ static char opts[64];
+ struct acpi_table_spcr *table;
+ acpi_size table_size;
+ acpi_status status;
+ char *uart;
+ char *iotype;
+ int baud_rate;
+ int err;
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ status = acpi_get_table_with_size(ACPI_SIG_SPCR, 0,
+ (struct acpi_table_header **)&table,
+ &table_size);
+
+ if (ACPI_FAILURE(status))
+ return -ENOENT;
+
+ if (table->header.revision < 2) {
+ err = -ENOENT;
+ pr_err("wrong table version\n");
+ goto done;
+ }
+
+ iotype = table->serial_port.space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY ?
+ "mmio" : "io";
+
+ switch (table->interface_type) {
+ case ACPI_DBG2_ARM_SBSA_32BIT:
+ iotype = "mmio32";
+ /* fall through */
+ case ACPI_DBG2_ARM_PL011:
+ case ACPI_DBG2_ARM_SBSA_GENERIC:
+ case ACPI_DBG2_BCM2835:
+ uart = "pl011";
+ break;
+ case ACPI_DBG2_16550_COMPATIBLE:
+ case ACPI_DBG2_16550_SUBSET:
+ uart = "uart";
+ break;
+ default:
+ err = -ENOENT;
+ goto done;
+ }
+
+ switch (table->baud_rate) {
+ case 3:
+ baud_rate = 9600;
+ break;
+ case 4:
+ baud_rate = 19200;
+ break;
+ case 6:
+ baud_rate = 57600;
+ break;
+ case 7:
+ baud_rate = 115200;
+ break;
+ default:
+ err = -ENOENT;
+ goto done;
+ }
+
+ snprintf(opts, sizeof(opts), "%s,%s,0x%llx,%d", uart, iotype,
+ table->serial_port.address, baud_rate);
+
+ pr_info("console: %s", opts);
+
+ if (earlycon)
+ setup_earlycon(opts);
+
+ err = add_preferred_console(uart, 0, opts + strlen(uart) + 1);
+
+done:
+ early_acpi_os_unmap_memory((void __iomem *)table, table_size);
+ return err;
+}
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 14f2f8c7c260..76211eaf2942 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -893,7 +893,7 @@ static inline void early_init_dt_check_for_initrd(unsigned long node)
#ifdef CONFIG_SERIAL_EARLYCON
-static int __init early_init_dt_scan_chosen_serial(void)
+int __init early_init_dt_scan_chosen_stdout(void)
{
int offset;
const char *p, *q, *options = NULL;
@@ -937,15 +937,6 @@ static int __init early_init_dt_scan_chosen_serial(void)
}
return -ENODEV;
}
-
-static int __init setup_of_earlycon(char *buf)
-{
- if (buf)
- return 0;
-
- return early_init_dt_scan_chosen_serial();
-}
-early_param("earlycon", setup_of_earlycon);
#endif
/**
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 1b7331e40d79..556d37cb9aa1 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2288,12 +2288,68 @@ static int __init pl011_console_setup(struct console *co, char *options)
return uart_set_options(&uap->port, co, baud, parity, bits, flow);
}
+/**
+ * pl011_console_match - non-standard console matching
+ * @co: registering console
+ * @name: name from console command line
+ * @idx: index from console command line
+ * @options: ptr to option string from console command line
+ *
+ * Only attempts to match console command lines of the form:
+ * console=pl011,mmio|mmio32,<addr>[,<options>]
+ * console=pl011,0x<addr>[,<options>]
+ * This form is used to register an initial earlycon boot console and
+ * replace it with the amba_console at pl011 driver init.
+ *
+ * Performs console setup for a match (as required by interface)
+ * If no <options> are specified, then assume the h/w is already setup.
+ *
+ * Returns 0 if console matches; otherwise non-zero to use default matching
+ */
+static int __init pl011_console_match(struct console *co, char *name, int idx,
+ char *options)
+{
+ char match[] = "pl011"; /* pl011-specific earlycon name */
+ unsigned char iotype;
+ unsigned long addr;
+ int i;
+
+ if (strncmp(name, match, 5) != 0)
+ return -ENODEV;
+
+ if (uart_parse_earlycon(options, &iotype, &addr, &options))
+ return -ENODEV;
+
+ /* try to match the port specified on the command line */
+ for (i = 0; i < ARRAY_SIZE(amba_ports); i++) {
+ struct uart_port *port;
+
+ if (!amba_ports[i])
+ continue;
+
+ port = &amba_ports[i]->port;
+
+ if (iotype != UPIO_MEM && iotype != UPIO_MEM32)
+ continue;
+
+ if (port->mapbase != addr)
+ continue;
+
+ co->index = i;
+ port->cons = co;
+ return pl011_console_setup(co, options);
+ }
+
+ return -ENODEV;
+}
+
static struct uart_driver amba_reg;
static struct console amba_console = {
.name = "ttyAMA",
.write = pl011_console_write,
.device = uart_console_device,
.setup = pl011_console_setup,
+ .match = pl011_console_match,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &amba_reg,
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 067783f0523c..ea00b9fde04f 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -21,6 +21,7 @@
#include <linux/sizes.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
+#include <linux/acpi.h>
#ifdef CONFIG_FIX_EARLYCON_MEM
#include <asm/fixmap.h>
@@ -199,6 +200,14 @@ int __init setup_earlycon(char *buf)
return -ENOENT;
}
+/*
+ * When CONFIG_ACPI_SPCR_TABLE is defined, "earlycon" without parameters in
+ * command line does not start DT earlycon immediately, instead it defers
+ * starting it until DT/ACPI decision is made. At that time if ACPI is enabled
+ * call parse_spcr(), else call early_init_dt_scan_chosen_stdout()
+ */
+bool earlycon_init_is_deferred __initdata;
+
/* early_param wrapper for setup_earlycon() */
static int __init param_setup_earlycon(char *buf)
{
@@ -208,8 +217,14 @@ static int __init param_setup_earlycon(char *buf)
* Just 'earlycon' is a valid param for devicetree earlycons;
* don't generate a warning from parse_early_params() in that case
*/
- if (!buf || !buf[0])
- return 0;
+ if (!buf || !buf[0]) {
+ if (IS_ENABLED(CONFIG_ACPI_SPCR_TABLE)) {
+ earlycon_init_is_deferred = true;
+ return 0;
+ } else {
+ return early_init_dt_scan_chosen_stdout();
+ }
+ }
err = setup_earlycon(buf);
if (err == -ENOENT || err == -EALREADY)
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 288fac5294f5..1de43be41ebc 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -997,4 +997,10 @@ static inline struct fwnode_handle *acpi_get_next_subnode(struct device *dev,
#define acpi_probe_device_table(t) ({ int __r = 0; __r;})
#endif
+#ifdef CONFIG_ACPI_SPCR_TABLE
+int parse_spcr(bool earlycon);
+#else
+static inline int parse_spcr(bool earlycon) { return 0; }
+#endif
+
#endif /*_LINUX_ACPI_H*/
diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
index 901ec01c9fba..370e7e43f290 100644
--- a/include/linux/of_fdt.h
+++ b/include/linux/of_fdt.h
@@ -64,6 +64,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
int depth, void *data);
extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
int depth, void *data);
+extern int early_init_dt_scan_chosen_stdout(void);
extern void early_init_fdt_scan_reserved_mem(void);
extern void early_init_fdt_reserve_self(void);
extern void early_init_dt_add_memory_arch(u64 base, u64 size);
@@ -92,6 +93,7 @@ extern void early_get_first_memblock_info(void *, phys_addr_t *);
extern u64 of_flat_dt_translate_address(unsigned long node);
extern void of_fdt_limit_memory(int limit);
#else /* CONFIG_OF_FLATTREE */
+static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
static inline void early_init_fdt_scan_reserved_mem(void) {}
static inline void early_init_fdt_reserve_self(void) {}
static inline const char *of_flat_dt_get_machine_name(void) { return NULL; }
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index a3d7c0d4a03e..60b614383b51 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -366,6 +366,12 @@ extern int of_setup_earlycon(const struct earlycon_id *match,
unsigned long node,
const char *options);
+#ifdef CONFIG_SERIAL_EARLYCON
+extern bool earlycon_init_is_deferred __initdata;
+#else
+static const bool earlycon_init_is_deferred;
+#endif
+
struct uart_port *uart_get_console(struct uart_port *ports, int nr,
struct console *c);
int uart_parse_earlycon(char *p, unsigned char *iotype, unsigned long *addr,