acpi_settings.c File Reference

ACPI settings. More...

#include <string.h>
#include <errno.h>
#include <ipxe/init.h>
#include <ipxe/settings.h>
#include <ipxe/acpi.h>

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
static int	acpi_settings_applies (struct settings *settings __unused, const struct setting *setting)
	Check applicability of ACPI setting. More...
static int	acpi_settings_fetch (struct settings *settings, struct setting *setting, void *data, size_t len)
	Fetch value of ACPI setting. More...
static void	acpi_settings_init (void)
	Initialise ACPI settings. More...
struct init_fn acpi_settings_init_fn	__init_fn (INIT_NORMAL)
	ACPI settings initialiser. More...

Variables
static const struct settings_scope	acpi_settings_scope
	ACPI settings scope. More...
static struct settings_operations	acpi_settings_operations
	ACPI settings operations. More...
static struct settings	acpi_settings
	ACPI settings. More...

Detailed Description

ACPI settings.

Definition in file acpi_settings.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

acpi_settings_applies()

static int acpi_settings_applies ( struct settings *settings  __unused, const struct setting *  setting  )

static

Check applicability of ACPI setting.

Parameters

settings	Settings block
setting	Setting

Return values

applies

Setting applies within this settings block

Definition at line 49 of file acpi_settings.c.

                                                                   {

        return ( setting->scope == &acpi_settings_scope );
}

References acpi_settings_scope, and setting::scope.

acpi_settings_fetch()

static int acpi_settings_fetch ( struct settings *  settings, struct setting *  setting, void *  data, size_t  len  )

static

Fetch value of ACPI setting.

Parameters

settings	Settings block
setting	Setting to fetch
data	Buffer to fill with setting data
len	Length of buffer

Return values

len	Length of setting data, or negative error

Definition at line 64 of file acpi_settings.c.

                                                          {
        const struct acpi_header *acpi;
        const uint8_t *src;
        uint8_t *dst;
        uint32_t tag_high;
        uint32_t tag_low;
        uint32_t tag_signature;
        unsigned int tag_index;
        size_t tag_offset;
        size_t tag_len;
        size_t offset;
        size_t max_len;
        int delta;
        unsigned int i;

        /* Parse settings tag */
        tag_high = ( setting->tag >> 32 );
        tag_low = setting->tag;
        tag_signature = bswap_32 ( tag_high );
        tag_index = ( ( tag_low >> 24 ) & 0xff );
        tag_offset = ( ( tag_low >> 8 ) & 0xffff );
        tag_len = ( ( tag_low >> 0 ) & 0xff );
        DBGC ( settings, "ACPI %s.%d offset %#zx length %#zx\n",
               acpi_name ( tag_signature ), tag_index, tag_offset, tag_len );

        /* Locate ACPI table */
        acpi = acpi_table ( tag_signature, tag_index );
        if ( ! acpi )
                return -ENOENT;

        /* Calculate starting offset and maximum available length */
        max_len = le32_to_cpu ( acpi->length );
        if ( tag_offset > max_len )
                return -ENOENT;
        offset = tag_offset;
        max_len -= offset;

        /* Restrict to requested length, if specified */
        if ( tag_len && ( tag_len < max_len ) )
                max_len = tag_len;

        /* Invert endianness for numeric settings */
        if ( setting->type && setting->type->numerate ) {
                offset += ( max_len - 1 );
                delta = -1;
        } else {
                delta = +1;
        }

        /* Read data */
        src = ( ( ( const void * ) acpi ) + offset );
        dst = data;
        for ( i = 0 ; ( ( i < max_len ) && ( i < len ) ) ; i++ ) {
                *(dst++) = *src;
                src += delta;
        }

        /* Set type if not already specified */
        if ( ! setting->type )
                setting->type = &setting_type_hexraw;

        return max_len;
}

References acpi, acpi_name(), acpi_table(), bswap_32, data, DBGC, ENOENT, le32_to_cpu, len, setting_type::numerate, offset, src, setting::tag, and setting::type.

acpi_settings_init()

static void acpi_settings_init ( void  )

static

Initialise ACPI settings.

Definition at line 146 of file acpi_settings.c.

                                        {
        int rc;

        if ( ( rc = register_settings ( &acpi_settings, NULL,
                                        "acpi" ) ) != 0 ) {
                DBG ( "ACPI could not register settings: %s\n",
                      strerror ( rc ) );
                return;
        }
}

References acpi_settings, DBG, NULL, rc, register_settings(), and strerror().

__init_fn()

struct init_fn acpi_settings_init_fn __init_fn

(

INIT_NORMAL

)

ACPI settings initialiser.

Variable Documentation

acpi_settings_scope

const struct settings_scope acpi_settings_scope

static

ACPI settings scope.

Definition at line 40 of file acpi_settings.c.

Referenced by acpi_settings_applies().

acpi_settings_operations

struct settings_operations acpi_settings_operations

static

Initial value:

= {
        .applies = acpi_settings_applies,
        .fetch = acpi_settings_fetch,
}

ACPI settings operations.

Definition at line 131 of file acpi_settings.c.

acpi_settings

struct settings acpi_settings

static

Initial value:

= {
        .refcnt = NULL,
        .siblings = LIST_HEAD_INIT ( acpi_settings.siblings ),
        .children = LIST_HEAD_INIT ( acpi_settings.children ),
        .op = &acpi_settings_operations,
        .default_scope = &acpi_settings_scope,
}

ACPI settings.

Definition at line 137 of file acpi_settings.c.

Referenced by acpi_settings_init().