From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/remoteproc/remoteproc_virtio.c | 363 +++++++++++++++++++++++++++++++++ 1 file changed, 363 insertions(+) create mode 100644 drivers/remoteproc/remoteproc_virtio.c (limited to 'drivers/remoteproc/remoteproc_virtio.c') diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c new file mode 100644 index 000000000..e1a10232a --- /dev/null +++ b/drivers/remoteproc/remoteproc_virtio.c @@ -0,0 +1,363 @@ +/* + * Remote processor messaging transport (OMAP platform-specific bits) + * + * Copyright (C) 2011 Texas Instruments, Inc. + * Copyright (C) 2011 Google, Inc. + * + * Ohad Ben-Cohen + * Brian Swetland + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +#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 id, + void (*callback)(struct virtqueue *vq), + const char *name) +{ + 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, ret; + + /* we're temporarily limited to two virtqueues per rvdev */ + if (id >= ARRAY_SIZE(rvdev->vring)) + return ERR_PTR(-EINVAL); + + if (!name) + return NULL; + + ret = rproc_alloc_vring(rvdev, id); + if (ret) + return ERR_PTR(ret); + + 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, 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); + rproc_free_vring(rvring); + } +} + +static void rproc_virtio_del_vqs(struct virtio_device *vdev) +{ + struct rproc *rproc = vdev_to_rproc(vdev); + + /* power down the remote processor before deleting vqs */ + rproc_shutdown(rproc); + + __rproc_virtio_del_vqs(vdev); +} + +static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs, + struct virtqueue *vqs[], + vq_callback_t *callbacks[], + const char *names[]) +{ + struct rproc *rproc = vdev_to_rproc(vdev); + int i, ret; + + for (i = 0; i < nvqs; ++i) { + vqs[i] = rp_find_vq(vdev, i, callbacks[i], names[i]); + if (IS_ERR(vqs[i])) { + ret = PTR_ERR(vqs[i]); + goto error; + } + } + + /* now that the vqs are all set, boot the remote processor */ + ret = rproc_boot(rproc); + if (ret) { + dev_err(&rproc->dev, "rproc_boot() failed %d\n", ret); + 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 offset, + void *buf, unsigned 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 offset, + const void *buf, unsigned 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_vdev_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); + + list_del(&rvdev->node); + kfree(rvdev); + + 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_vdev_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); + + 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); +} -- cgit v1.2.3-54-g00ecf