linux/drivers/ide/ide-acpi.c
Kees Cook 3f649ab728 treewide: Remove uninitialized_var() usage
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-16 12:35:15 -07:00

623 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Provides ACPI support for IDE drives.
*
* Copyright (C) 2005 Intel Corp.
* Copyright (C) 2005 Randy Dunlap
* Copyright (C) 2006 SUSE Linux Products GmbH
* Copyright (C) 2006 Hannes Reinecke
*/
#include <linux/acpi.h>
#include <linux/ata.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/ide.h>
#include <linux/pci.h>
#include <linux/dmi.h>
#include <linux/module.h>
#define REGS_PER_GTF 7
struct GTM_buffer {
u32 PIO_speed0;
u32 DMA_speed0;
u32 PIO_speed1;
u32 DMA_speed1;
u32 GTM_flags;
};
struct ide_acpi_drive_link {
acpi_handle obj_handle;
u8 idbuff[512];
};
struct ide_acpi_hwif_link {
ide_hwif_t *hwif;
acpi_handle obj_handle;
struct GTM_buffer gtm;
struct ide_acpi_drive_link master;
struct ide_acpi_drive_link slave;
};
#undef DEBUGGING
/* note: adds function name and KERN_DEBUG */
#ifdef DEBUGGING
#define DEBPRINT(fmt, args...) \
printk(KERN_DEBUG "%s: " fmt, __func__, ## args)
#else
#define DEBPRINT(fmt, args...) do {} while (0)
#endif /* DEBUGGING */
static bool ide_noacpi;
module_param_named(noacpi, ide_noacpi, bool, 0);
MODULE_PARM_DESC(noacpi, "disable IDE ACPI support");
static bool ide_acpigtf;
module_param_named(acpigtf, ide_acpigtf, bool, 0);
MODULE_PARM_DESC(acpigtf, "enable IDE ACPI _GTF support");
static bool ide_acpionboot;
module_param_named(acpionboot, ide_acpionboot, bool, 0);
MODULE_PARM_DESC(acpionboot, "call IDE ACPI methods on boot");
static bool ide_noacpi_psx;
static int no_acpi_psx(const struct dmi_system_id *id)
{
ide_noacpi_psx = true;
printk(KERN_NOTICE"%s detected - disable ACPI _PSx.\n", id->ident);
return 0;
}
static const struct dmi_system_id ide_acpi_dmi_table[] = {
/* Bug 9673. */
/* We should check if this is because ACPI NVS isn't save/restored. */
{
.callback = no_acpi_psx,
.ident = "HP nx9005",
.matches = {
DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies Ltd."),
DMI_MATCH(DMI_BIOS_VERSION, "KAM1.60")
},
},
{ } /* terminate list */
};
int ide_acpi_init(void)
{
dmi_check_system(ide_acpi_dmi_table);
return 0;
}
bool ide_port_acpi(ide_hwif_t *hwif)
{
return ide_noacpi == 0 && hwif->acpidata;
}
static acpi_handle acpi_get_child(acpi_handle handle, u64 addr)
{
struct acpi_device *adev;
if (!handle || acpi_bus_get_device(handle, &adev))
return NULL;
adev = acpi_find_child_device(adev, addr, false);
return adev ? adev->handle : NULL;
}
/**
* ide_get_dev_handle - finds acpi_handle and PCI device.function
* @dev: device to locate
* @handle: returned acpi_handle for @dev
* @pcidevfn: return PCI device.func for @dev
*
* Returns the ACPI object handle to the corresponding PCI device.
*
* Returns 0 on success, <0 on error.
*/
static int ide_get_dev_handle(struct device *dev, acpi_handle *handle,
u64 *pcidevfn)
{
struct pci_dev *pdev = to_pci_dev(dev);
unsigned int bus, devnum, func;
u64 addr;
acpi_handle dev_handle;
acpi_status status;
struct acpi_device_info *dinfo = NULL;
int ret = -ENODEV;
bus = pdev->bus->number;
devnum = PCI_SLOT(pdev->devfn);
func = PCI_FUNC(pdev->devfn);
/* ACPI _ADR encoding for PCI bus: */
addr = (u64)(devnum << 16 | func);
DEBPRINT("ENTER: pci %02x:%02x.%01x\n", bus, devnum, func);
dev_handle = ACPI_HANDLE(dev);
if (!dev_handle) {
DEBPRINT("no acpi handle for device\n");
goto err;
}
status = acpi_get_object_info(dev_handle, &dinfo);
if (ACPI_FAILURE(status)) {
DEBPRINT("get_object_info for device failed\n");
goto err;
}
if (dinfo && (dinfo->valid & ACPI_VALID_ADR) &&
dinfo->address == addr) {
*pcidevfn = addr;
*handle = dev_handle;
} else {
DEBPRINT("get_object_info for device has wrong "
" address: %llu, should be %u\n",
dinfo ? (unsigned long long)dinfo->address : -1ULL,
(unsigned int)addr);
goto err;
}
DEBPRINT("for dev=0x%x.%x, addr=0x%llx, *handle=0x%p\n",
devnum, func, (unsigned long long)addr, *handle);
ret = 0;
err:
kfree(dinfo);
return ret;
}
/**
* ide_acpi_hwif_get_handle - Get ACPI object handle for a given hwif
* @hwif: device to locate
*
* Retrieves the object handle for a given hwif.
*
* Returns handle on success, 0 on error.
*/
static acpi_handle ide_acpi_hwif_get_handle(ide_hwif_t *hwif)
{
struct device *dev = hwif->gendev.parent;
acpi_handle dev_handle;
u64 pcidevfn;
acpi_handle chan_handle;
int err;
DEBPRINT("ENTER: device %s\n", hwif->name);
if (!dev) {
DEBPRINT("no PCI device for %s\n", hwif->name);
return NULL;
}
err = ide_get_dev_handle(dev, &dev_handle, &pcidevfn);
if (err < 0) {
DEBPRINT("ide_get_dev_handle failed (%d)\n", err);
return NULL;
}
/* get child objects of dev_handle == channel objects,
* + _their_ children == drive objects */
/* channel is hwif->channel */
chan_handle = acpi_get_child(dev_handle, hwif->channel);
DEBPRINT("chan adr=%d: handle=0x%p\n",
hwif->channel, chan_handle);
return chan_handle;
}
/**
* do_drive_get_GTF - get the drive bootup default taskfile settings
* @drive: the drive for which the taskfile settings should be retrieved
* @gtf_length: number of bytes of _GTF data returned at @gtf_address
* @gtf_address: buffer containing _GTF taskfile arrays
*
* The _GTF method has no input parameters.
* It returns a variable number of register set values (registers
* hex 1F1..1F7, taskfiles).
* The <variable number> is not known in advance, so have ACPI-CA
* allocate the buffer as needed and return it, then free it later.
*
* The returned @gtf_length and @gtf_address are only valid if the
* function return value is 0.
*/
static int do_drive_get_GTF(ide_drive_t *drive,
unsigned int *gtf_length, unsigned long *gtf_address,
unsigned long *obj_loc)
{
acpi_status status;
struct acpi_buffer output;
union acpi_object *out_obj;
int err = -ENODEV;
*gtf_length = 0;
*gtf_address = 0UL;
*obj_loc = 0UL;
if (!drive->acpidata->obj_handle) {
DEBPRINT("No ACPI object found for %s\n", drive->name);
goto out;
}
/* Setting up output buffer */
output.length = ACPI_ALLOCATE_BUFFER;
output.pointer = NULL; /* ACPI-CA sets this; save/free it later */
/* _GTF has no input parameters */
err = -EIO;
status = acpi_evaluate_object(drive->acpidata->obj_handle, "_GTF",
NULL, &output);
if (ACPI_FAILURE(status)) {
printk(KERN_DEBUG
"%s: Run _GTF error: status = 0x%x\n",
__func__, status);
goto out;
}
if (!output.length || !output.pointer) {
DEBPRINT("Run _GTF: "
"length or ptr is NULL (0x%llx, 0x%p)\n",
(unsigned long long)output.length,
output.pointer);
goto out;
}
out_obj = output.pointer;
if (out_obj->type != ACPI_TYPE_BUFFER) {
DEBPRINT("Run _GTF: error: "
"expected object type of ACPI_TYPE_BUFFER, "
"got 0x%x\n", out_obj->type);
err = -ENOENT;
kfree(output.pointer);
goto out;
}
if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
out_obj->buffer.length % REGS_PER_GTF) {
printk(KERN_ERR
"%s: unexpected GTF length (%d) or addr (0x%p)\n",
__func__, out_obj->buffer.length,
out_obj->buffer.pointer);
err = -ENOENT;
kfree(output.pointer);
goto out;
}
*gtf_length = out_obj->buffer.length;
*gtf_address = (unsigned long)out_obj->buffer.pointer;
*obj_loc = (unsigned long)out_obj;
DEBPRINT("returning gtf_length=%d, gtf_address=0x%lx, obj_loc=0x%lx\n",
*gtf_length, *gtf_address, *obj_loc);
err = 0;
out:
return err;
}
/**
* do_drive_set_taskfiles - write the drive taskfile settings from _GTF
* @drive: the drive to which the taskfile command should be sent
* @gtf_length: total number of bytes of _GTF taskfiles
* @gtf_address: location of _GTF taskfile arrays
*
* Write {gtf_address, length gtf_length} in groups of
* REGS_PER_GTF bytes.
*/
static int do_drive_set_taskfiles(ide_drive_t *drive,
unsigned int gtf_length,
unsigned long gtf_address)
{
int rc = 0, err;
int gtf_count = gtf_length / REGS_PER_GTF;
int ix;
DEBPRINT("total GTF bytes=%u (0x%x), gtf_count=%d, addr=0x%lx\n",
gtf_length, gtf_length, gtf_count, gtf_address);
/* send all taskfile registers (0x1f1-0x1f7) *in*that*order* */
for (ix = 0; ix < gtf_count; ix++) {
u8 *gtf = (u8 *)(gtf_address + ix * REGS_PER_GTF);
struct ide_cmd cmd;
DEBPRINT("(0x1f1-1f7): "
"hex: %02x %02x %02x %02x %02x %02x %02x\n",
gtf[0], gtf[1], gtf[2],
gtf[3], gtf[4], gtf[5], gtf[6]);
if (!ide_acpigtf) {
DEBPRINT("_GTF execution disabled\n");
continue;
}
/* convert GTF to taskfile */
memset(&cmd, 0, sizeof(cmd));
memcpy(&cmd.tf.feature, gtf, REGS_PER_GTF);
cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
cmd.valid.in.tf = IDE_VALID_IN_TF | IDE_VALID_DEVICE;
err = ide_no_data_taskfile(drive, &cmd);
if (err) {
printk(KERN_ERR "%s: ide_no_data_taskfile failed: %u\n",
__func__, err);
rc = err;
}
}
return rc;
}
/**
* ide_acpi_exec_tfs - get then write drive taskfile settings
* @drive: the drive for which the taskfile settings should be
* written.
*
* According to the ACPI spec this should be called after _STM
* has been evaluated for the interface. Some ACPI vendors interpret
* that as a hard requirement and modify the taskfile according
* to the Identify Drive information passed down with _STM.
* So one should really make sure to call this only after _STM has
* been executed.
*/
int ide_acpi_exec_tfs(ide_drive_t *drive)
{
int ret;
unsigned int gtf_length;
unsigned long gtf_address;
unsigned long obj_loc;
DEBPRINT("call get_GTF, drive=%s port=%d\n", drive->name, drive->dn);
ret = do_drive_get_GTF(drive, &gtf_length, &gtf_address, &obj_loc);
if (ret < 0) {
DEBPRINT("get_GTF error (%d)\n", ret);
return ret;
}
DEBPRINT("call set_taskfiles, drive=%s\n", drive->name);
ret = do_drive_set_taskfiles(drive, gtf_length, gtf_address);
kfree((void *)obj_loc);
if (ret < 0) {
DEBPRINT("set_taskfiles error (%d)\n", ret);
}
DEBPRINT("ret=%d\n", ret);
return ret;
}
/**
* ide_acpi_get_timing - get the channel (controller) timings
* @hwif: target IDE interface (channel)
*
* This function executes the _GTM ACPI method for the target channel.
*
*/
void ide_acpi_get_timing(ide_hwif_t *hwif)
{
acpi_status status;
struct acpi_buffer output;
union acpi_object *out_obj;
/* Setting up output buffer for _GTM */
output.length = ACPI_ALLOCATE_BUFFER;
output.pointer = NULL; /* ACPI-CA sets this; save/free it later */
/* _GTM has no input parameters */
status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_GTM",
NULL, &output);
DEBPRINT("_GTM status: %d, outptr: 0x%p, outlen: 0x%llx\n",
status, output.pointer,
(unsigned long long)output.length);
if (ACPI_FAILURE(status)) {
DEBPRINT("Run _GTM error: status = 0x%x\n", status);
return;
}
if (!output.length || !output.pointer) {
DEBPRINT("Run _GTM: length or ptr is NULL (0x%llx, 0x%p)\n",
(unsigned long long)output.length,
output.pointer);
kfree(output.pointer);
return;
}
out_obj = output.pointer;
if (out_obj->type != ACPI_TYPE_BUFFER) {
DEBPRINT("Run _GTM: error: "
"expected object type of ACPI_TYPE_BUFFER, "
"got 0x%x\n", out_obj->type);
kfree(output.pointer);
return;
}
if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
out_obj->buffer.length != sizeof(struct GTM_buffer)) {
printk(KERN_ERR
"%s: unexpected _GTM length (0x%x)[should be 0x%zx] or "
"addr (0x%p)\n",
__func__, out_obj->buffer.length,
sizeof(struct GTM_buffer), out_obj->buffer.pointer);
kfree(output.pointer);
return;
}
memcpy(&hwif->acpidata->gtm, out_obj->buffer.pointer,
sizeof(struct GTM_buffer));
DEBPRINT("_GTM info: ptr: 0x%p, len: 0x%x, exp.len: 0x%zx\n",
out_obj->buffer.pointer, out_obj->buffer.length,
sizeof(struct GTM_buffer));
DEBPRINT("_GTM fields: 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
hwif->acpidata->gtm.PIO_speed0,
hwif->acpidata->gtm.DMA_speed0,
hwif->acpidata->gtm.PIO_speed1,
hwif->acpidata->gtm.DMA_speed1,
hwif->acpidata->gtm.GTM_flags);
kfree(output.pointer);
}
/**
* ide_acpi_push_timing - set the channel (controller) timings
* @hwif: target IDE interface (channel)
*
* This function executes the _STM ACPI method for the target channel.
*
* _STM requires Identify Drive data, which has to passed as an argument.
* Unfortunately drive->id is a mangled version which we can't readily
* use; hence we'll get the information afresh.
*/
void ide_acpi_push_timing(ide_hwif_t *hwif)
{
acpi_status status;
struct acpi_object_list input;
union acpi_object in_params[3];
struct ide_acpi_drive_link *master = &hwif->acpidata->master;
struct ide_acpi_drive_link *slave = &hwif->acpidata->slave;
/* Give the GTM buffer + drive Identify data to the channel via the
* _STM method: */
/* setup input parameters buffer for _STM */
input.count = 3;
input.pointer = in_params;
in_params[0].type = ACPI_TYPE_BUFFER;
in_params[0].buffer.length = sizeof(struct GTM_buffer);
in_params[0].buffer.pointer = (u8 *)&hwif->acpidata->gtm;
in_params[1].type = ACPI_TYPE_BUFFER;
in_params[1].buffer.length = ATA_ID_WORDS * 2;
in_params[1].buffer.pointer = (u8 *)&master->idbuff;
in_params[2].type = ACPI_TYPE_BUFFER;
in_params[2].buffer.length = ATA_ID_WORDS * 2;
in_params[2].buffer.pointer = (u8 *)&slave->idbuff;
/* Output buffer: _STM has no output */
status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_STM",
&input, NULL);
if (ACPI_FAILURE(status)) {
DEBPRINT("Run _STM error: status = 0x%x\n", status);
}
DEBPRINT("_STM status: %d\n", status);
}
/**
* ide_acpi_set_state - set the channel power state
* @hwif: target IDE interface
* @on: state, on/off
*
* This function executes the _PS0/_PS3 ACPI method to set the power state.
* ACPI spec requires _PS0 when IDE power on and _PS3 when power off
*/
void ide_acpi_set_state(ide_hwif_t *hwif, int on)
{
ide_drive_t *drive;
int i;
if (ide_noacpi_psx)
return;
DEBPRINT("ENTER:\n");
/* channel first and then drives for power on and verse versa for power off */
if (on)
acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D0);
ide_port_for_each_present_dev(i, drive, hwif) {
if (drive->acpidata->obj_handle)
acpi_bus_set_power(drive->acpidata->obj_handle,
on ? ACPI_STATE_D0 : ACPI_STATE_D3_COLD);
}
if (!on)
acpi_bus_set_power(hwif->acpidata->obj_handle,
ACPI_STATE_D3_COLD);
}
/**
* ide_acpi_init_port - initialize the ACPI link for an IDE interface
* @hwif: target IDE interface (channel)
*
* The ACPI spec is not quite clear when the drive identify buffer
* should be obtained. Calling IDENTIFY DEVICE during shutdown
* is not the best of ideas as the drive might already being put to
* sleep. And obviously we can't call it during resume.
* So we get the information during startup; but this means that
* any changes during run-time will be lost after resume.
*/
void ide_acpi_init_port(ide_hwif_t *hwif)
{
hwif->acpidata = kzalloc(sizeof(struct ide_acpi_hwif_link), GFP_KERNEL);
if (!hwif->acpidata)
return;
hwif->acpidata->obj_handle = ide_acpi_hwif_get_handle(hwif);
if (!hwif->acpidata->obj_handle) {
DEBPRINT("no ACPI object for %s found\n", hwif->name);
kfree(hwif->acpidata);
hwif->acpidata = NULL;
}
}
void ide_acpi_port_init_devices(ide_hwif_t *hwif)
{
ide_drive_t *drive;
int i, err;
if (hwif->acpidata == NULL)
return;
/*
* The ACPI spec mandates that we send information
* for both drives, regardless whether they are connected
* or not.
*/
hwif->devices[0]->acpidata = &hwif->acpidata->master;
hwif->devices[1]->acpidata = &hwif->acpidata->slave;
/* get _ADR info for each device */
ide_port_for_each_present_dev(i, drive, hwif) {
acpi_handle dev_handle;
DEBPRINT("ENTER: %s at channel#: %d port#: %d\n",
drive->name, hwif->channel, drive->dn & 1);
/* TBD: could also check ACPI object VALID bits */
dev_handle = acpi_get_child(hwif->acpidata->obj_handle,
drive->dn & 1);
DEBPRINT("drive %s handle 0x%p\n", drive->name, dev_handle);
drive->acpidata->obj_handle = dev_handle;
}
/* send IDENTIFY for each device */
ide_port_for_each_present_dev(i, drive, hwif) {
err = taskfile_lib_get_identify(drive, drive->acpidata->idbuff);
if (err)
DEBPRINT("identify device %s failed (%d)\n",
drive->name, err);
}
if (ide_noacpi || ide_acpionboot == 0) {
DEBPRINT("ACPI methods disabled on boot\n");
return;
}
/* ACPI _PS0 before _STM */
ide_acpi_set_state(hwif, 1);
/*
* ACPI requires us to call _STM on startup
*/
ide_acpi_get_timing(hwif);
ide_acpi_push_timing(hwif);
ide_port_for_each_present_dev(i, drive, hwif) {
ide_acpi_exec_tfs(drive);
}
}