diff options
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/Kconfig | 3 | ||||
| -rw-r--r-- | drivers/acpi/Makefile | 1 | ||||
| -rw-r--r-- | drivers/acpi/spcr.c | 111 |
3 files changed, 115 insertions, 0 deletions
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 445ce28..a984cc7 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 5ae9d85..c469516 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/spcr.c b/drivers/acpi/spcr.c new file mode 100644 index 0000000..e8d7bc7 --- /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\n", 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; +} |
