linux-stable/include/linux/remoteproc.h
Bjorn Andersson dc5192c449 remoteproc: Introduce "panic" callback in ops
Introduce generic support for handling kernel panics in remoteproc
drivers, in order to allow operations needed for aiding in post mortem
system debugging, such as flushing caches etc.

The function can return a number of milliseconds needed by the remote to
"settle" and the core will wait the longest returned duration before
returning from the panic handler.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200324052904.738594-3-bjorn.andersson@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2020-03-25 22:29:45 -07:00

642 lines
22 KiB
C

/*
* Remote Processor Framework
*
* Copyright(c) 2011 Texas Instruments, Inc.
* Copyright(c) 2011 Google, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name Texas Instruments nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef REMOTEPROC_H
#define REMOTEPROC_H
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/virtio.h>
#include <linux/completion.h>
#include <linux/idr.h>
#include <linux/of.h>
/**
* struct resource_table - firmware resource table header
* @ver: version number
* @num: number of resource entries
* @reserved: reserved (must be zero)
* @offset: array of offsets pointing at the various resource entries
*
* A resource table is essentially a list of system resources required
* by the remote processor. It may also include configuration entries.
* If needed, the remote processor firmware should contain this table
* as a dedicated ".resource_table" ELF section.
*
* Some resources entries are mere announcements, where the host is informed
* of specific remoteproc configuration. Other entries require the host to
* do something (e.g. allocate a system resource). Sometimes a negotiation
* is expected, where the firmware requests a resource, and once allocated,
* the host should provide back its details (e.g. address of an allocated
* memory region).
*
* The header of the resource table, as expressed by this structure,
* contains a version number (should we need to change this format in the
* future), the number of available resource entries, and their offsets
* in the table.
*
* Immediately following this header are the resource entries themselves,
* each of which begins with a resource entry header (as described below).
*/
struct resource_table {
u32 ver;
u32 num;
u32 reserved[2];
u32 offset[0];
} __packed;
/**
* struct fw_rsc_hdr - firmware resource entry header
* @type: resource type
* @data: resource data
*
* Every resource entry begins with a 'struct fw_rsc_hdr' header providing
* its @type. The content of the entry itself will immediately follow
* this header, and it should be parsed according to the resource type.
*/
struct fw_rsc_hdr {
u32 type;
u8 data[0];
} __packed;
/**
* enum fw_resource_type - types of resource entries
*
* @RSC_CARVEOUT: request for allocation of a physically contiguous
* memory region.
* @RSC_DEVMEM: request to iommu_map a memory-based peripheral.
* @RSC_TRACE: announces the availability of a trace buffer into which
* the remote processor will be writing logs.
* @RSC_VDEV: declare support for a virtio device, and serve as its
* virtio header.
* @RSC_LAST: just keep this one at the end of standard resources
* @RSC_VENDOR_START: start of the vendor specific resource types range
* @RSC_VENDOR_END: end of the vendor specific resource types range
*
* For more details regarding a specific resource type, please see its
* dedicated structure below.
*
* Please note that these values are used as indices to the rproc_handle_rsc
* lookup table, so please keep them sane. Moreover, @RSC_LAST is used to
* check the validity of an index before the lookup table is accessed, so
* please update it as needed.
*/
enum fw_resource_type {
RSC_CARVEOUT = 0,
RSC_DEVMEM = 1,
RSC_TRACE = 2,
RSC_VDEV = 3,
RSC_LAST = 4,
RSC_VENDOR_START = 128,
RSC_VENDOR_END = 512,
};
#define FW_RSC_ADDR_ANY (-1)
/**
* struct fw_rsc_carveout - physically contiguous memory request
* @da: device address
* @pa: physical address
* @len: length (in bytes)
* @flags: iommu protection flags
* @reserved: reserved (must be zero)
* @name: human-readable name of the requested memory region
*
* This resource entry requests the host to allocate a physically contiguous
* memory region.
*
* These request entries should precede other firmware resource entries,
* as other entries might request placing other data objects inside
* these memory regions (e.g. data/code segments, trace resource entries, ...).
*
* Allocating memory this way helps utilizing the reserved physical memory
* (e.g. CMA) more efficiently, and also minimizes the number of TLB entries
* needed to map it (in case @rproc is using an IOMMU). Reducing the TLB
* pressure is important; it may have a substantial impact on performance.
*
* If the firmware is compiled with static addresses, then @da should specify
* the expected device address of this memory region. If @da is set to
* FW_RSC_ADDR_ANY, then the host will dynamically allocate it, and then
* overwrite @da with the dynamically allocated address.
*
* We will always use @da to negotiate the device addresses, even if it
* isn't using an iommu. In that case, though, it will obviously contain
* physical addresses.
*
* Some remote processors needs to know the allocated physical address
* even if they do use an iommu. This is needed, e.g., if they control
* hardware accelerators which access the physical memory directly (this
* is the case with OMAP4 for instance). In that case, the host will
* overwrite @pa with the dynamically allocated physical address.
* Generally we don't want to expose physical addresses if we don't have to
* (remote processors are generally _not_ trusted), so we might want to
* change this to happen _only_ when explicitly required by the hardware.
*
* @flags is used to provide IOMMU protection flags, and @name should
* (optionally) contain a human readable name of this carveout region
* (mainly for debugging purposes).
*/
struct fw_rsc_carveout {
u32 da;
u32 pa;
u32 len;
u32 flags;
u32 reserved;
u8 name[32];
} __packed;
/**
* struct fw_rsc_devmem - iommu mapping request
* @da: device address
* @pa: physical address
* @len: length (in bytes)
* @flags: iommu protection flags
* @reserved: reserved (must be zero)
* @name: human-readable name of the requested region to be mapped
*
* This resource entry requests the host to iommu map a physically contiguous
* memory region. This is needed in case the remote processor requires
* access to certain memory-based peripherals; _never_ use it to access
* regular memory.
*
* This is obviously only needed if the remote processor is accessing memory
* via an iommu.
*
* @da should specify the required device address, @pa should specify
* the physical address we want to map, @len should specify the size of
* the mapping and @flags is the IOMMU protection flags. As always, @name may
* (optionally) contain a human readable name of this mapping (mainly for
* debugging purposes).
*
* Note: at this point we just "trust" those devmem entries to contain valid
* physical addresses, but this isn't safe and will be changed: eventually we
* want remoteproc implementations to provide us ranges of physical addresses
* the firmware is allowed to request, and not allow firmwares to request
* access to physical addresses that are outside those ranges.
*/
struct fw_rsc_devmem {
u32 da;
u32 pa;
u32 len;
u32 flags;
u32 reserved;
u8 name[32];
} __packed;
/**
* struct fw_rsc_trace - trace buffer declaration
* @da: device address
* @len: length (in bytes)
* @reserved: reserved (must be zero)
* @name: human-readable name of the trace buffer
*
* This resource entry provides the host information about a trace buffer
* into which the remote processor will write log messages.
*
* @da specifies the device address of the buffer, @len specifies
* its size, and @name may contain a human readable name of the trace buffer.
*
* After booting the remote processor, the trace buffers are exposed to the
* user via debugfs entries (called trace0, trace1, etc..).
*/
struct fw_rsc_trace {
u32 da;
u32 len;
u32 reserved;
u8 name[32];
} __packed;
/**
* struct fw_rsc_vdev_vring - vring descriptor entry
* @da: device address
* @align: the alignment between the consumer and producer parts of the vring
* @num: num of buffers supported by this vring (must be power of two)
* @notifyid is a unique rproc-wide notify index for this vring. This notify
* index is used when kicking a remote processor, to let it know that this
* vring is triggered.
* @pa: physical address
*
* This descriptor is not a resource entry by itself; it is part of the
* vdev resource type (see below).
*
* Note that @da should either contain the device address where
* the remote processor is expecting the vring, or indicate that
* dynamically allocation of the vring's device address is supported.
*/
struct fw_rsc_vdev_vring {
u32 da;
u32 align;
u32 num;
u32 notifyid;
u32 pa;
} __packed;
/**
* struct fw_rsc_vdev - virtio device header
* @id: virtio device id (as in virtio_ids.h)
* @notifyid is a unique rproc-wide notify index for this vdev. This notify
* index is used when kicking a remote processor, to let it know that the
* status/features of this vdev have changes.
* @dfeatures specifies the virtio device features supported by the firmware
* @gfeatures is a place holder used by the host to write back the
* negotiated features that are supported by both sides.
* @config_len is the size of the virtio config space of this vdev. The config
* space lies in the resource table immediate after this vdev header.
* @status is a place holder where the host will indicate its virtio progress.
* @num_of_vrings indicates how many vrings are described in this vdev header
* @reserved: reserved (must be zero)
* @vring is an array of @num_of_vrings entries of 'struct fw_rsc_vdev_vring'.
*
* This resource is a virtio device header: it provides information about
* the vdev, and is then used by the host and its peer remote processors
* to negotiate and share certain virtio properties.
*
* By providing this resource entry, the firmware essentially asks remoteproc
* to statically allocate a vdev upon registration of the rproc (dynamic vdev
* allocation is not yet supported).
*
* Note: unlike virtualization systems, the term 'host' here means
* the Linux side which is running remoteproc to control the remote
* processors. We use the name 'gfeatures' to comply with virtio's terms,
* though there isn't really any virtualized guest OS here: it's the host
* which is responsible for negotiating the final features.
* Yeah, it's a bit confusing.
*
* Note: immediately following this structure is the virtio config space for
* this vdev (which is specific to the vdev; for more info, read the virtio
* spec). the size of the config space is specified by @config_len.
*/
struct fw_rsc_vdev {
u32 id;
u32 notifyid;
u32 dfeatures;
u32 gfeatures;
u32 config_len;
u8 status;
u8 num_of_vrings;
u8 reserved[2];
struct fw_rsc_vdev_vring vring[0];
} __packed;
struct rproc;
/**
* struct rproc_mem_entry - memory entry descriptor
* @va: virtual address
* @dma: dma address
* @len: length, in bytes
* @da: device address
* @release: release associated memory
* @priv: associated data
* @name: associated memory region name (optional)
* @node: list node
* @rsc_offset: offset in resource table
* @flags: iommu protection flags
* @of_resm_idx: reserved memory phandle index
* @alloc: specific memory allocator function
*/
struct rproc_mem_entry {
void *va;
dma_addr_t dma;
size_t len;
u32 da;
void *priv;
char name[32];
struct list_head node;
u32 rsc_offset;
u32 flags;
u32 of_resm_idx;
int (*alloc)(struct rproc *rproc, struct rproc_mem_entry *mem);
int (*release)(struct rproc *rproc, struct rproc_mem_entry *mem);
};
struct firmware;
/**
* enum rsc_handling_status - return status of rproc_ops handle_rsc hook
* @RSC_HANDLED: resource was handled
* @RSC_IGNORED: resource was ignored
*/
enum rsc_handling_status {
RSC_HANDLED = 0,
RSC_IGNORED = 1,
};
/**
* struct rproc_ops - platform-specific device handlers
* @start: power on the device and boot it
* @stop: power off the device
* @kick: kick a virtqueue (virtqueue id given as a parameter)
* @da_to_va: optional platform hook to perform address translations
* @parse_fw: parse firmware to extract information (e.g. resource table)
* @handle_rsc: optional platform hook to handle vendor resources. Should return
* RSC_HANDLED if resource was handled, RSC_IGNORED if not handled and a
* negative value on error
* @load_rsc_table: load resource table from firmware image
* @find_loaded_rsc_table: find the loaded resouce table
* @load: load firmware to memory, where the remote processor
* expects to find it
* @sanity_check: sanity check the fw image
* @get_boot_addr: get boot address to entry point specified in firmware
* @panic: optional callback to react to system panic, core will delay
* panic at least the returned number of milliseconds
*/
struct rproc_ops {
int (*start)(struct rproc *rproc);
int (*stop)(struct rproc *rproc);
void (*kick)(struct rproc *rproc, int vqid);
void * (*da_to_va)(struct rproc *rproc, u64 da, size_t len);
int (*parse_fw)(struct rproc *rproc, const struct firmware *fw);
int (*handle_rsc)(struct rproc *rproc, u32 rsc_type, void *rsc,
int offset, int avail);
struct resource_table *(*find_loaded_rsc_table)(
struct rproc *rproc, const struct firmware *fw);
int (*load)(struct rproc *rproc, const struct firmware *fw);
int (*sanity_check)(struct rproc *rproc, const struct firmware *fw);
u64 (*get_boot_addr)(struct rproc *rproc, const struct firmware *fw);
unsigned long (*panic)(struct rproc *rproc);
};
/**
* enum rproc_state - remote processor states
* @RPROC_OFFLINE: device is powered off
* @RPROC_SUSPENDED: device is suspended; needs to be woken up to receive
* a message.
* @RPROC_RUNNING: device is up and running
* @RPROC_CRASHED: device has crashed; need to start recovery
* @RPROC_DELETED: device is deleted
* @RPROC_LAST: just keep this one at the end
*
* Please note that the values of these states are used as indices
* to rproc_state_string, a state-to-name lookup table,
* so please keep the two synchronized. @RPROC_LAST is used to check
* the validity of an index before the lookup table is accessed, so
* please update it as needed too.
*/
enum rproc_state {
RPROC_OFFLINE = 0,
RPROC_SUSPENDED = 1,
RPROC_RUNNING = 2,
RPROC_CRASHED = 3,
RPROC_DELETED = 4,
RPROC_LAST = 5,
};
/**
* enum rproc_crash_type - remote processor crash types
* @RPROC_MMUFAULT: iommu fault
* @RPROC_WATCHDOG: watchdog bite
* @RPROC_FATAL_ERROR fatal error
*
* Each element of the enum is used as an array index. So that, the value of
* the elements should be always something sane.
*
* Feel free to add more types when needed.
*/
enum rproc_crash_type {
RPROC_MMUFAULT,
RPROC_WATCHDOG,
RPROC_FATAL_ERROR,
};
/**
* struct rproc_dump_segment - segment info from ELF header
* @node: list node related to the rproc segment list
* @da: device address of the segment
* @size: size of the segment
* @priv: private data associated with the dump_segment
* @dump: custom dump function to fill device memory segment associated
* with coredump
*/
struct rproc_dump_segment {
struct list_head node;
dma_addr_t da;
size_t size;
void *priv;
void (*dump)(struct rproc *rproc, struct rproc_dump_segment *segment,
void *dest);
loff_t offset;
};
/**
* struct rproc - represents a physical remote processor device
* @node: list node of this rproc object
* @domain: iommu domain
* @name: human readable name of the rproc
* @firmware: name of firmware file to be loaded
* @priv: private data which belongs to the platform-specific rproc module
* @ops: platform-specific start/stop rproc handlers
* @dev: virtual device for refcounting and common remoteproc behavior
* @power: refcount of users who need this rproc powered up
* @state: state of the device
* @lock: lock which protects concurrent manipulations of the rproc
* @dbg_dir: debugfs directory of this rproc device
* @traces: list of trace buffers
* @num_traces: number of trace buffers
* @carveouts: list of physically contiguous memory allocations
* @mappings: list of iommu mappings we initiated, needed on shutdown
* @bootaddr: address of first instruction to boot rproc with (optional)
* @rvdevs: list of remote virtio devices
* @subdevs: list of subdevices, to following the running state
* @notifyids: idr for dynamically assigning rproc-wide unique notify ids
* @index: index of this rproc device
* @crash_handler: workqueue for handling a crash
* @crash_cnt: crash counter
* @recovery_disabled: flag that state if recovery was disabled
* @max_notifyid: largest allocated notify id.
* @table_ptr: pointer to the resource table in effect
* @cached_table: copy of the resource table
* @table_sz: size of @cached_table
* @has_iommu: flag to indicate if remote processor is behind an MMU
* @auto_boot: flag to indicate if remote processor should be auto-started
* @dump_segments: list of segments in the firmware
* @nb_vdev: number of vdev currently handled by rproc
*/
struct rproc {
struct list_head node;
struct iommu_domain *domain;
const char *name;
char *firmware;
void *priv;
struct rproc_ops *ops;
struct device dev;
atomic_t power;
unsigned int state;
struct mutex lock;
struct dentry *dbg_dir;
struct list_head traces;
int num_traces;
struct list_head carveouts;
struct list_head mappings;
u64 bootaddr;
struct list_head rvdevs;
struct list_head subdevs;
struct idr notifyids;
int index;
struct work_struct crash_handler;
unsigned int crash_cnt;
bool recovery_disabled;
int max_notifyid;
struct resource_table *table_ptr;
struct resource_table *cached_table;
size_t table_sz;
bool has_iommu;
bool auto_boot;
struct list_head dump_segments;
int nb_vdev;
u8 elf_class;
};
/**
* struct rproc_subdev - subdevice tied to a remoteproc
* @node: list node related to the rproc subdevs list
* @prepare: prepare function, called before the rproc is started
* @start: start function, called after the rproc has been started
* @stop: stop function, called before the rproc is stopped; the @crashed
* parameter indicates if this originates from a recovery
* @unprepare: unprepare function, called after the rproc has been stopped
*/
struct rproc_subdev {
struct list_head node;
int (*prepare)(struct rproc_subdev *subdev);
int (*start)(struct rproc_subdev *subdev);
void (*stop)(struct rproc_subdev *subdev, bool crashed);
void (*unprepare)(struct rproc_subdev *subdev);
};
/* we currently support only two vrings per rvdev */
#define RVDEV_NUM_VRINGS 2
/**
* struct rproc_vring - remoteproc vring state
* @va: virtual address
* @len: length, in bytes
* @da: device address
* @align: vring alignment
* @notifyid: rproc-specific unique vring index
* @rvdev: remote vdev
* @vq: the virtqueue of this vring
*/
struct rproc_vring {
void *va;
int len;
u32 da;
u32 align;
int notifyid;
struct rproc_vdev *rvdev;
struct virtqueue *vq;
};
/**
* struct rproc_vdev - remoteproc state for a supported virtio device
* @refcount: reference counter for the vdev and vring allocations
* @subdev: handle for registering the vdev as a rproc subdevice
* @id: virtio device id (as in virtio_ids.h)
* @node: list node
* @rproc: the rproc handle
* @vdev: the virio device
* @vring: the vrings for this vdev
* @rsc_offset: offset of the vdev's resource entry
* @index: vdev position versus other vdev declared in resource table
*/
struct rproc_vdev {
struct kref refcount;
struct rproc_subdev subdev;
struct device dev;
unsigned int id;
struct list_head node;
struct rproc *rproc;
struct rproc_vring vring[RVDEV_NUM_VRINGS];
u32 rsc_offset;
u32 index;
};
struct rproc *rproc_get_by_phandle(phandle phandle);
struct rproc *rproc_get_by_child(struct device *dev);
struct rproc *rproc_alloc(struct device *dev, const char *name,
const struct rproc_ops *ops,
const char *firmware, int len);
void rproc_put(struct rproc *rproc);
int rproc_add(struct rproc *rproc);
int rproc_del(struct rproc *rproc);
void rproc_free(struct rproc *rproc);
void rproc_add_carveout(struct rproc *rproc, struct rproc_mem_entry *mem);
struct rproc_mem_entry *
rproc_mem_entry_init(struct device *dev,
void *va, dma_addr_t dma, size_t len, u32 da,
int (*alloc)(struct rproc *, struct rproc_mem_entry *),
int (*release)(struct rproc *, struct rproc_mem_entry *),
const char *name, ...);
struct rproc_mem_entry *
rproc_of_resm_mem_entry_init(struct device *dev, u32 of_resm_idx, size_t len,
u32 da, const char *name, ...);
int rproc_boot(struct rproc *rproc);
void rproc_shutdown(struct rproc *rproc);
void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type);
int rproc_coredump_add_segment(struct rproc *rproc, dma_addr_t da, size_t size);
int rproc_coredump_add_custom_segment(struct rproc *rproc,
dma_addr_t da, size_t size,
void (*dumpfn)(struct rproc *rproc,
struct rproc_dump_segment *segment,
void *dest),
void *priv);
static inline struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev)
{
return container_of(vdev->dev.parent, struct rproc_vdev, dev);
}
static inline struct rproc *vdev_to_rproc(struct virtio_device *vdev)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
return rvdev->rproc;
}
void rproc_add_subdev(struct rproc *rproc, struct rproc_subdev *subdev);
void rproc_remove_subdev(struct rproc *rproc, struct rproc_subdev *subdev);
#endif /* REMOTEPROC_H */