linux/drivers/firmware/google/coreboot_table-acpi.c
Samuel Holland 570d30c282 firmware: coreboot: Expose the coreboot table as a bus
This simplifies creating device drivers for hardware or information
described in the coreboot table. It also avoids needing to search
through the table every time a driver is loaded.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-23 13:37:19 +02:00

89 lines
2.2 KiB
C

/*
* coreboot_table-acpi.c
*
* Using ACPI to locate Coreboot table and provide coreboot table access.
*
* Copyright 2017 Google Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License v2.0 as published by
* the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include "coreboot_table.h"
static int coreboot_table_acpi_probe(struct platform_device *pdev)
{
phys_addr_t phyaddr;
resource_size_t len;
struct coreboot_table_header __iomem *header = NULL;
struct resource *res;
void __iomem *ptr = NULL;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -EINVAL;
len = resource_size(res);
if (!res->start || !len)
return -EINVAL;
phyaddr = res->start;
header = ioremap_cache(phyaddr, sizeof(*header));
if (header == NULL)
return -ENOMEM;
ptr = ioremap_cache(phyaddr,
header->header_bytes + header->table_bytes);
iounmap(header);
if (!ptr)
return -ENOMEM;
return coreboot_table_init(&pdev->dev, ptr);
}
static int coreboot_table_acpi_remove(struct platform_device *pdev)
{
return coreboot_table_exit();
}
static const struct acpi_device_id cros_coreboot_acpi_match[] = {
{ "GOOGCB00", 0 },
{ "BOOT0000", 0 },
{ }
};
MODULE_DEVICE_TABLE(acpi, cros_coreboot_acpi_match);
static struct platform_driver coreboot_table_acpi_driver = {
.probe = coreboot_table_acpi_probe,
.remove = coreboot_table_acpi_remove,
.driver = {
.name = "coreboot_table_acpi",
.acpi_match_table = ACPI_PTR(cros_coreboot_acpi_match),
},
};
static int __init coreboot_table_acpi_init(void)
{
return platform_driver_register(&coreboot_table_acpi_driver);
}
module_init(coreboot_table_acpi_init);
MODULE_AUTHOR("Google, Inc.");
MODULE_LICENSE("GPL");