linux/drivers/remoteproc/remoteproc_virtio.c
Michael S. Tsirkin f94682dde5 virtio: add context flag to find vqs
Allows maintaining extra context per vq.  For ease of use, passing in
NULL is legal and disables the feature for all vqs.

Includes fixes by Christian for s390, acked by Cornelia.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-02 23:41:43 +03:00

351 lines
9.1 KiB
C

/*
* Remote processor messaging transport (OMAP platform-specific bits)
*
* Copyright (C) 2011 Texas Instruments, Inc.
* Copyright (C) 2011 Google, Inc.
*
* Ohad Ben-Cohen <ohad@wizery.com>
* Brian Swetland <swetland@google.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* 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/export.h>
#include <linux/remoteproc.h>
#include <linux/virtio.h>
#include <linux/virtio_config.h>
#include <linux/virtio_ids.h>
#include <linux/virtio_ring.h>
#include <linux/err.h>
#include <linux/kref.h>
#include <linux/slab.h>
#include "remoteproc_internal.h"
/* kick the remote processor, and let it know which virtqueue to poke at */
static bool rproc_virtio_notify(struct virtqueue *vq)
{
struct rproc_vring *rvring = vq->priv;
struct rproc *rproc = rvring->rvdev->rproc;
int notifyid = rvring->notifyid;
dev_dbg(&rproc->dev, "kicking vq index: %d\n", notifyid);
rproc->ops->kick(rproc, notifyid);
return true;
}
/**
* rproc_vq_interrupt() - tell remoteproc that a virtqueue is interrupted
* @rproc: handle to the remote processor
* @notifyid: index of the signalled virtqueue (unique per this @rproc)
*
* This function should be called by the platform-specific rproc driver,
* when the remote processor signals that a specific virtqueue has pending
* messages available.
*
* Returns IRQ_NONE if no message was found in the @notifyid virtqueue,
* and otherwise returns IRQ_HANDLED.
*/
irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int notifyid)
{
struct rproc_vring *rvring;
dev_dbg(&rproc->dev, "vq index %d is interrupted\n", notifyid);
rvring = idr_find(&rproc->notifyids, notifyid);
if (!rvring || !rvring->vq)
return IRQ_NONE;
return vring_interrupt(0, rvring->vq);
}
EXPORT_SYMBOL(rproc_vq_interrupt);
static struct virtqueue *rp_find_vq(struct virtio_device *vdev,
unsigned int id,
void (*callback)(struct virtqueue *vq),
const char *name, bool ctx)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct rproc *rproc = vdev_to_rproc(vdev);
struct device *dev = &rproc->dev;
struct rproc_vring *rvring;
struct virtqueue *vq;
void *addr;
int len, size;
/* we're temporarily limited to two virtqueues per rvdev */
if (id >= ARRAY_SIZE(rvdev->vring))
return ERR_PTR(-EINVAL);
if (!name)
return NULL;
rvring = &rvdev->vring[id];
addr = rvring->va;
len = rvring->len;
/* zero vring */
size = vring_size(len, rvring->align);
memset(addr, 0, size);
dev_dbg(dev, "vring%d: va %p qsz %d notifyid %d\n",
id, addr, len, rvring->notifyid);
/*
* Create the new vq, and tell virtio we're not interested in
* the 'weak' smp barriers, since we're talking with a real device.
*/
vq = vring_new_virtqueue(id, len, rvring->align, vdev, false, ctx,
addr, rproc_virtio_notify, callback, name);
if (!vq) {
dev_err(dev, "vring_new_virtqueue %s failed\n", name);
rproc_free_vring(rvring);
return ERR_PTR(-ENOMEM);
}
rvring->vq = vq;
vq->priv = rvring;
return vq;
}
static void __rproc_virtio_del_vqs(struct virtio_device *vdev)
{
struct virtqueue *vq, *n;
struct rproc_vring *rvring;
list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
rvring = vq->priv;
rvring->vq = NULL;
vring_del_virtqueue(vq);
}
}
static void rproc_virtio_del_vqs(struct virtio_device *vdev)
{
__rproc_virtio_del_vqs(vdev);
}
static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char * const names[],
const bool * ctx,
struct irq_affinity *desc)
{
int i, ret;
for (i = 0; i < nvqs; ++i) {
vqs[i] = rp_find_vq(vdev, i, callbacks[i], names[i],
ctx ? ctx[i] : false);
if (IS_ERR(vqs[i])) {
ret = PTR_ERR(vqs[i]);
goto error;
}
}
return 0;
error:
__rproc_virtio_del_vqs(vdev);
return ret;
}
static u8 rproc_virtio_get_status(struct virtio_device *vdev)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct fw_rsc_vdev *rsc;
rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
return rsc->status;
}
static void rproc_virtio_set_status(struct virtio_device *vdev, u8 status)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct fw_rsc_vdev *rsc;
rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
rsc->status = status;
dev_dbg(&vdev->dev, "status: %d\n", status);
}
static void rproc_virtio_reset(struct virtio_device *vdev)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct fw_rsc_vdev *rsc;
rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
rsc->status = 0;
dev_dbg(&vdev->dev, "reset !\n");
}
/* provide the vdev features as retrieved from the firmware */
static u64 rproc_virtio_get_features(struct virtio_device *vdev)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct fw_rsc_vdev *rsc;
rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
return rsc->dfeatures;
}
static int rproc_virtio_finalize_features(struct virtio_device *vdev)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct fw_rsc_vdev *rsc;
rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
/* Give virtio_ring a chance to accept features */
vring_transport_features(vdev);
/* Make sure we don't have any features > 32 bits! */
BUG_ON((u32)vdev->features != vdev->features);
/*
* Remember the finalized features of our vdev, and provide it
* to the remote processor once it is powered on.
*/
rsc->gfeatures = vdev->features;
return 0;
}
static void rproc_virtio_get(struct virtio_device *vdev, unsigned int offset,
void *buf, unsigned int len)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct fw_rsc_vdev *rsc;
void *cfg;
rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
cfg = &rsc->vring[rsc->num_of_vrings];
if (offset + len > rsc->config_len || offset + len < len) {
dev_err(&vdev->dev, "rproc_virtio_get: access out of bounds\n");
return;
}
memcpy(buf, cfg + offset, len);
}
static void rproc_virtio_set(struct virtio_device *vdev, unsigned int offset,
const void *buf, unsigned int len)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct fw_rsc_vdev *rsc;
void *cfg;
rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
cfg = &rsc->vring[rsc->num_of_vrings];
if (offset + len > rsc->config_len || offset + len < len) {
dev_err(&vdev->dev, "rproc_virtio_set: access out of bounds\n");
return;
}
memcpy(cfg + offset, buf, len);
}
static const struct virtio_config_ops rproc_virtio_config_ops = {
.get_features = rproc_virtio_get_features,
.finalize_features = rproc_virtio_finalize_features,
.find_vqs = rproc_virtio_find_vqs,
.del_vqs = rproc_virtio_del_vqs,
.reset = rproc_virtio_reset,
.set_status = rproc_virtio_set_status,
.get_status = rproc_virtio_get_status,
.get = rproc_virtio_get,
.set = rproc_virtio_set,
};
/*
* This function is called whenever vdev is released, and is responsible
* to decrement the remote processor's refcount which was taken when vdev was
* added.
*
* Never call this function directly; it will be called by the driver
* core when needed.
*/
static void rproc_virtio_dev_release(struct device *dev)
{
struct virtio_device *vdev = dev_to_virtio(dev);
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
struct rproc *rproc = vdev_to_rproc(vdev);
kref_put(&rvdev->refcount, rproc_vdev_release);
put_device(&rproc->dev);
}
/**
* rproc_add_virtio_dev() - register an rproc-induced virtio device
* @rvdev: the remote vdev
*
* This function registers a virtio device. This vdev's partent is
* the rproc device.
*
* Returns 0 on success or an appropriate error value otherwise.
*/
int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
{
struct rproc *rproc = rvdev->rproc;
struct device *dev = &rproc->dev;
struct virtio_device *vdev = &rvdev->vdev;
int ret;
vdev->id.device = id,
vdev->config = &rproc_virtio_config_ops,
vdev->dev.parent = dev;
vdev->dev.release = rproc_virtio_dev_release;
/*
* We're indirectly making a non-temporary copy of the rproc pointer
* here, because drivers probed with this vdev will indirectly
* access the wrapping rproc.
*
* Therefore we must increment the rproc refcount here, and decrement
* it _only_ when the vdev is released.
*/
get_device(&rproc->dev);
/* Reference the vdev and vring allocations */
kref_get(&rvdev->refcount);
ret = register_virtio_device(vdev);
if (ret) {
put_device(&rproc->dev);
dev_err(dev, "failed to register vdev: %d\n", ret);
goto out;
}
dev_info(dev, "registered %s (type %d)\n", dev_name(&vdev->dev), id);
out:
return ret;
}
/**
* rproc_remove_virtio_dev() - remove an rproc-induced virtio device
* @rvdev: the remote vdev
*
* This function unregisters an existing virtio device.
*/
void rproc_remove_virtio_dev(struct rproc_vdev *rvdev)
{
unregister_virtio_device(&rvdev->vdev);
}