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Diffstat (limited to 'include/linux/remoteproc.h')
| -rw-r--r-- | include/linux/remoteproc.h | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h new file mode 100644 index 00000000000..f1ffabb978d --- /dev/null +++ b/include/linux/remoteproc.h @@ -0,0 +1,478 @@ +/* + * 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/kref.h> +#include <linux/klist.h> +#include <linux/mutex.h> +#include <linux/virtio.h> +#include <linux/completion.h> +#include <linux/idr.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 + * + * 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, +}; + +#define FW_RSC_ADDR_ANY (0xFFFFFFFFFFFFFFFF) + +/** + * 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. + * @reserved: reserved (must be zero) + * + * 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 reserved; +} __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_mem_entry - memory entry descriptor + * @va: virtual address + * @dma: dma address + * @len: length, in bytes + * @da: device address + * @priv: associated data + * @node: list node + */ +struct rproc_mem_entry { + void *va; + dma_addr_t dma; + int len; + u32 da; + void *priv; + struct list_head node; +}; + +struct rproc; + +/** + * 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) + */ +struct rproc_ops { + int (*start)(struct rproc *rproc); + int (*stop)(struct rproc *rproc); + void (*kick)(struct rproc *rproc, int vqid); +}; + +/** + * 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_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_LAST = 4, +}; + +/** + * struct rproc - represents a physical remote processor device + * @node: klist 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: underlying device + * @refcount: refcount of users that have a valid pointer to this rproc + * @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 + * @firmware_loading_complete: marks e/o asynchronous firmware loading + * @bootaddr: address of first instruction to boot rproc with (optional) + * @rvdevs: list of remote virtio devices + * @notifyids: idr for dynamically assigning rproc-wide unique notify ids + */ +struct rproc { + struct klist_node node; + struct iommu_domain *domain; + const char *name; + const char *firmware; + void *priv; + const struct rproc_ops *ops; + struct device *dev; + struct kref refcount; + 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; + struct completion firmware_loading_complete; + u32 bootaddr; + struct list_head rvdevs; + struct idr notifyids; +}; + +/* we currently support only two vrings per rvdev */ +#define RVDEV_NUM_VRINGS 2 + +/** + * struct rproc_vring - remoteproc vring state + * @va: virtual address + * @dma: dma 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; + dma_addr_t dma; + 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 + * @node: list node + * @rproc: the rproc handle + * @vdev: the virio device + * @vring: the vrings for this vdev + * @dfeatures: virtio device features + * @gfeatures: virtio guest features + */ +struct rproc_vdev { + struct list_head node; + struct rproc *rproc; + struct virtio_device vdev; + struct rproc_vring vring[RVDEV_NUM_VRINGS]; + unsigned long dfeatures; + unsigned long gfeatures; +}; + +struct rproc *rproc_get_by_name(const char *name); +void rproc_put(struct rproc *rproc); + +struct rproc *rproc_alloc(struct device *dev, const char *name, + const struct rproc_ops *ops, + const char *firmware, int len); +void rproc_free(struct rproc *rproc); +int rproc_register(struct rproc *rproc); +int rproc_unregister(struct rproc *rproc); + +int rproc_boot(struct rproc *rproc); +void rproc_shutdown(struct rproc *rproc); + +static inline struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev) +{ + return container_of(vdev, struct rproc_vdev, vdev); +} + +static inline struct rproc *vdev_to_rproc(struct virtio_device *vdev) +{ + struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); + + return rvdev->rproc; +} + +#endif /* REMOTEPROC_H */ |