hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

platform/x86: dell-smbios-wmi: Add new WMI dispatcher driver 

The dell-smbios stack only currently uses an SMI interface which grants
direct access to physical memory to the firmware SMM methods via a pointer.

This dispatcher driver adds a WMI-ACPI interface that is detected by WMI
probe and preferred over the SMI interface in dell-smbios.

Changing this to operate over WMI-ACPI will use an ACPI OperationRegion
for a buffer of data storage when SMM calls are performed.

This is a safer approach to use in kernel drivers as the SMM will
only have access to that OperationRegion.

Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Reviewed-by: Edward O'Callaghan <quasisec@google.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
This commit is contained in:
Mario Limonciello 2017-11-01 14:25:32 -05:00 committed by Darren Hart (VMware)
parent 549b4930f0
commit 1a258e6704
4 changed files with 257 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
MAINTAINERS
View File

@ -3991,6 +3991,12 @@ L: platform-driver-x86@vger.kernel.org
S: Maintained
F: drivers/platform/x86/dell-smbios-smm.c
DELL SMBIOS WMI DRIVER
M: Mario Limonciello <mario.limonciello@dell.com>
L: platform-driver-x86@vger.kernel.org
S: Maintained
F: drivers/platform/x86/dell-smbios-wmi.c
DELL LAPTOP DRIVER
M: Matthew Garrett <mjg59@srcf.ucam.org>
M: Pali Rohár <pali.rohar@gmail.com>

14
drivers/platform/x86/Kconfig
View File

@ -94,6 +94,20 @@ config ASUS_LAPTOP
config DELL_SMBIOS
tristate
config DELL_SMBIOS_WMI
tristate "Dell SMBIOS calling interface (WMI implementation)"
depends on ACPI_WMI
select DELL_WMI_DESCRIPTOR
default ACPI_WMI
select DELL_SMBIOS
---help---
This provides an implementation for the Dell SMBIOS calling interface
communicated over ACPI-WMI.
If you have a Dell computer from >2007 you should say Y or M here.
If you aren't sure and this module doesn't work for your computer
it just won't load.
config DELL_SMBIOS_SMM
tristate "Dell SMBIOS calling interface (SMM implementation)"
depends on DCDBAS

1
drivers/platform/x86/Makefile
View File

@ -12,6 +12,7 @@ obj-$(CONFIG_MSI_LAPTOP) += msi-laptop.o
obj-$(CONFIG_ACPI_CMPC) += classmate-laptop.o
obj-$(CONFIG_COMPAL_LAPTOP) += compal-laptop.o
obj-$(CONFIG_DELL_SMBIOS) += dell-smbios.o
obj-$(CONFIG_DELL_SMBIOS_WMI) += dell-smbios-wmi.o
obj-$(CONFIG_DELL_SMBIOS_SMM) += dell-smbios-smm.o
obj-$(CONFIG_DELL_LAPTOP) += dell-laptop.o
obj-$(CONFIG_DELL_WMI) += dell-wmi.o

236
drivers/platform/x86/dell-smbios-wmi.c Normal file
View File

@ -0,0 +1,236 @@
/*
* WMI methods for use with dell-smbios
*
* Copyright (c) 2017 Dell Inc.
*
* 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) KBUILD_MODNAME ": " fmt
#include <linux/dmi.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>
#include <linux/wmi.h>
#include "dell-smbios.h"
#include "dell-wmi-descriptor.h"
static DEFINE_MUTEX(call_mutex);
static DEFINE_MUTEX(list_mutex);
static int wmi_supported;
struct misc_bios_flags_structure {
struct dmi_header header;
u16 flags0;
} __packed;
#define FLAG_HAS_ACPI_WMI 0x02
#define DELL_WMI_SMBIOS_GUID "A80593CE-A997-11DA-B012-B622A1EF5492"
struct dell_wmi_extensions {
__u32 argattrib;
__u32 blength;
__u8 data[];
} __packed;
struct dell_wmi_smbios_buffer {
struct calling_interface_buffer std;
struct dell_wmi_extensions ext;
} __packed;
struct wmi_smbios_priv {
struct dell_wmi_smbios_buffer *buf;
struct list_head list;
struct wmi_device *wdev;
struct device *child;
u32 req_buf_size;
};
static LIST_HEAD(wmi_list);
static inline struct wmi_smbios_priv *get_first_smbios_priv(void)
{
return list_first_entry_or_null(&wmi_list,
struct wmi_smbios_priv,
list);
}
static int run_smbios_call(struct wmi_device *wdev)
{
struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
struct wmi_smbios_priv *priv;
struct acpi_buffer input;
union acpi_object *obj;
acpi_status status;
priv = dev_get_drvdata(&wdev->dev);
input.length = priv->req_buf_size - sizeof(u64);
input.pointer = &priv->buf->std;
dev_dbg(&wdev->dev, "evaluating: %u/%u [%x,%x,%x,%x]\n",
priv->buf->std.cmd_class, priv->buf->std.cmd_select,
priv->buf->std.input[0], priv->buf->std.input[1],
priv->buf->std.input[2], priv->buf->std.input[3]);
status = wmidev_evaluate_method(wdev, 0, 1, &input, &output);
if (ACPI_FAILURE(status))
return -EIO;
obj = (union acpi_object *)output.pointer;
if (obj->type != ACPI_TYPE_BUFFER) {
dev_dbg(&wdev->dev, "received type: %d\n", obj->type);
if (obj->type == ACPI_TYPE_INTEGER)
dev_dbg(&wdev->dev, "SMBIOS call failed: %llu\n",
obj->integer.value);
return -EIO;
}
memcpy(&priv->buf->std, obj->buffer.pointer, obj->buffer.length);
dev_dbg(&wdev->dev, "result: [%08x,%08x,%08x,%08x]\n",
priv->buf->std.output[0], priv->buf->std.output[1],
priv->buf->std.output[2], priv->buf->std.output[3]);
return 0;
}
int dell_smbios_wmi_call(struct calling_interface_buffer *buffer)
{
struct wmi_smbios_priv *priv;
size_t difference;
size_t size;
int ret;
mutex_lock(&call_mutex);
priv = get_first_smbios_priv();
if (!priv)
return -ENODEV;
size = sizeof(struct calling_interface_buffer);
difference = priv->req_buf_size - sizeof(u64) - size;
memset(&priv->buf->ext, 0, difference);
memcpy(&priv->buf->std, buffer, size);
ret = run_smbios_call(priv->wdev);
memcpy(buffer, &priv->buf->std, size);
mutex_unlock(&call_mutex);
return ret;
}
static int dell_smbios_wmi_probe(struct wmi_device *wdev)
{
struct wmi_smbios_priv *priv;
int count;
int ret;
if (!wmi_has_guid(DELL_WMI_DESCRIPTOR_GUID))
return -ENODEV;
priv = devm_kzalloc(&wdev->dev, sizeof(struct wmi_smbios_priv),
GFP_KERNEL);
if (!priv)
return -ENOMEM;
/* WMI buffer size will be either 4k or 32k depending on machine */
if (!dell_wmi_get_size(&priv->req_buf_size))
return -EPROBE_DEFER;
count = get_order(priv->req_buf_size);
priv->buf = (void *)__get_free_pages(GFP_KERNEL, count);
if (!priv->buf)
return -ENOMEM;
/* ID is used by dell-smbios to set priority of drivers */
wdev->dev.id = 1;
ret = dell_smbios_register_device(&wdev->dev, &dell_smbios_wmi_call);
if (ret)
goto fail_register;
priv->wdev = wdev;
dev_set_drvdata(&wdev->dev, priv);
mutex_lock(&list_mutex);
list_add_tail(&priv->list, &wmi_list);
mutex_unlock(&list_mutex);
return 0;
fail_register:
free_pages((unsigned long)priv->buf, count);
return ret;
}
static int dell_smbios_wmi_remove(struct wmi_device *wdev)
{
struct wmi_smbios_priv *priv = dev_get_drvdata(&wdev->dev);
int count;
mutex_lock(&call_mutex);
mutex_lock(&list_mutex);
list_del(&priv->list);
mutex_unlock(&list_mutex);
dell_smbios_unregister_device(&wdev->dev);
count = get_order(priv->req_buf_size);
free_pages((unsigned long)priv->buf, count);
mutex_unlock(&call_mutex);
return 0;
}
static const struct wmi_device_id dell_smbios_wmi_id_table[] = {
{ .guid_string = DELL_WMI_SMBIOS_GUID },
{ },
};
static void __init parse_b1_table(const struct dmi_header *dm)
{
struct misc_bios_flags_structure *flags =
container_of(dm, struct misc_bios_flags_structure, header);
/* 4 bytes header, 8 bytes flags */
if (dm->length < 12)
return;
if (dm->handle != 0xb100)
return;
if ((flags->flags0 & FLAG_HAS_ACPI_WMI))
wmi_supported = 1;
}
static void __init find_b1(const struct dmi_header *dm, void *dummy)
{
switch (dm->type) {
case 0xb1: /* misc bios flags */
parse_b1_table(dm);
break;
}
}
static struct wmi_driver dell_smbios_wmi_driver = {
.driver = {
.name = "dell-smbios",
},
.probe = dell_smbios_wmi_probe,
.remove = dell_smbios_wmi_remove,
.id_table = dell_smbios_wmi_id_table,
};
static int __init init_dell_smbios_wmi(void)
{
dmi_walk(find_b1, NULL);
if (!wmi_supported)
return -ENODEV;
return wmi_driver_register(&dell_smbios_wmi_driver);
}
static void __exit exit_dell_smbios_wmi(void)
{
wmi_driver_unregister(&dell_smbios_wmi_driver);
}
module_init(init_dell_smbios_wmi);
module_exit(exit_dell_smbios_wmi);
MODULE_ALIAS("wmi:" DELL_WMI_SMBIOS_GUID);
MODULE_AUTHOR("Mario Limonciello <mario.limonciello@dell.com>");
MODULE_DESCRIPTION("Dell SMBIOS communications over WMI");
MODULE_LICENSE("GPL");