[mirror_ubuntu-focal-kernel.git] / drivers / remoteproc / remoteproc_virtio.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * 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>
 */

#include <linux/dma-mapping.h>
#include <linux/export.h>
#include <linux/of_reserved_mem.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_mem_entry *mem;
	struct rproc_vring *rvring;
	struct fw_rsc_vdev *rsc;
	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;

	/* Search allocated memory region by name */
	mem = rproc_find_carveout_by_name(rproc, "vdev%dvring%d", rvdev->index,
					  id);
	if (!mem || !mem->va)
		return ERR_PTR(-ENOMEM);

	rvring = &rvdev->vring[id];
	addr = mem->va;
	len = rvring->len;

	/* zero vring */
	size = vring_size(len, rvring->align);
	memset(addr, 0, size);

	dev_dbg(dev, "vring%d: va %pK 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;

	/* Update vring in resource table */
	rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
	rsc->vring[id].da = mem->da;

	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, queue_idx = 0;

	for (i = 0; i < nvqs; ++i) {
		if (!names[i]) {
			vqs[i] = NULL;
			continue;
		}

		vqs[i] = rp_find_vq(vdev, queue_idx++, 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 void rproc_transport_features(struct virtio_device *vdev)
{
	/*
	 * Packed ring isn't enabled on remoteproc for now,
	 * because remoteproc uses vring_new_virtqueue() which
	 * creates virtio rings on preallocated memory.
	 */
	__virtio_clear_bit(vdev, VIRTIO_F_RING_PACKED);
}

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);

	/* Give virtio_rproc a chance to accept features. */
	rproc_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);

	kfree(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 = &rvdev->dev;
	struct virtio_device *vdev;
	struct rproc_mem_entry *mem;
	int ret;

	/* Try to find dedicated vdev buffer carveout */
	mem = rproc_find_carveout_by_name(rproc, "vdev%dbuffer", rvdev->index);
	if (mem) {
		phys_addr_t pa;

		if (mem->of_resm_idx != -1) {
			struct device_node *np = rproc->dev.parent->of_node;

			/* Associate reserved memory to vdev device */
			ret = of_reserved_mem_device_init_by_idx(dev, np,
								 mem->of_resm_idx);
			if (ret) {
				dev_err(dev, "Can't associate reserved memory\n");
				goto out;
			}
		} else {
			if (mem->va) {
				dev_warn(dev, "vdev %d buffer already mapped\n",
					 rvdev->index);
				pa = rproc_va_to_pa(mem->va);
			} else {
				/* Use dma address as carveout no memmapped yet */
				pa = (phys_addr_t)mem->dma;
			}

			/* Associate vdev buffer memory pool to vdev subdev */
			ret = dma_declare_coherent_memory(dev, pa,
							   mem->da,
							   mem->len);
			if (ret < 0) {
				dev_err(dev, "Failed to associate buffer\n");
				goto out;
			}
		}
	}

	/* Allocate virtio device */
	vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
	if (!vdev) {
		ret = -ENOMEM;
		goto out;
	}
	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(&vdev->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
 * @dev: the virtio device
 * @data: must be null
 *
 * This function unregisters an existing virtio device.
 */
int rproc_remove_virtio_dev(struct device *dev, void *data)
{
	struct virtio_device *vdev = dev_to_virtio(dev);

	unregister_virtio_device(vdev);
	return 0;
}
Commit	Line	Data
9c92ab61	1	// SPDX-License-Identifier: GPL-2.0-only
ac8954a4 OBC	2	/*
	3	* Remote processor messaging transport (OMAP platform-specific bits)
	4	*
	5	* Copyright (C) 2011 Texas Instruments, Inc.
	6	* Copyright (C) 2011 Google, Inc.
	7	*
	8	* Ohad Ben-Cohen <ohad@wizery.com>
	9	* Brian Swetland <swetland@google.com>
ac8954a4 OBC	10	*/
ac8954a4 OBC	11
086d0872	12	#include <linux/dma-mapping.h>
ac8954a4	13	#include <linux/export.h>
086d0872	14	#include <linux/of_reserved_mem.h>
ac8954a4	15	#include <linux/remoteproc.h>
ac8954a4 OBC	16	#include <linux/virtio.h>
	17	#include <linux/virtio_config.h>
	18	#include <linux/virtio_ids.h>
	19	#include <linux/virtio_ring.h>
	20	#include <linux/err.h>
	21	#include <linux/kref.h>
	22	#include <linux/slab.h>
	23
	24	#include "remoteproc_internal.h"
	25
ac8954a4	26	/* kick the remote processor, and let it know which virtqueue to poke at */
46f9c2b9	27	static bool rproc_virtio_notify(struct virtqueue *vq)
ac8954a4	28	{
7a186941 OBC	29	struct rproc_vring *rvring = vq->priv;
	30	struct rproc *rproc = rvring->rvdev->rproc;
	31	int notifyid = rvring->notifyid;
ac8954a4	32
b5ab5e24	33	dev_dbg(&rproc->dev, "kicking vq index: %d\n", notifyid);
ac8954a4	34
7a186941	35	rproc->ops->kick(rproc, notifyid);
46f9c2b9	36	return true;
ac8954a4 OBC	37	}
	38
	39	/**
	40	* rproc_vq_interrupt() - tell remoteproc that a virtqueue is interrupted
	41	* @rproc: handle to the remote processor
7a186941	42	* @notifyid: index of the signalled virtqueue (unique per this @rproc)
ac8954a4 OBC	43	*
	44	* This function should be called by the platform-specific rproc driver,
	45	* when the remote processor signals that a specific virtqueue has pending
	46	* messages available.
	47	*
7a186941	48	* Returns IRQ_NONE if no message was found in the @notifyid virtqueue,
ac8954a4 OBC	49	* and otherwise returns IRQ_HANDLED.
ac8954a4 OBC	50	*/
7a186941	51	irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int notifyid)
ac8954a4	52	{
7a186941 OBC	53	struct rproc_vring *rvring;
7a186941 OBC	54
b5ab5e24	55	dev_dbg(&rproc->dev, "vq index %d is interrupted\n", notifyid);
7a186941 OBC	56
	57	rvring = idr_find(&rproc->notifyids, notifyid);
	58	if (!rvring \|\| !rvring->vq)
	59	return IRQ_NONE;
	60
	61	return vring_interrupt(0, rvring->vq);
ac8954a4 OBC	62	}
	63	EXPORT_SYMBOL(rproc_vq_interrupt);
	64
	65	static struct virtqueue rp_find_vq(struct virtio_device vdev,
f145928d	66	unsigned int id,
ac8954a4	67	void (callback)(struct virtqueue vq),
f94682dd	68	const char *name, bool ctx)
ac8954a4	69	{
7a186941	70	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
ac8954a4	71	struct rproc *rproc = vdev_to_rproc(vdev);
b5ab5e24	72	struct device *dev = &rproc->dev;
c6aed238	73	struct rproc_mem_entry *mem;
7a186941	74	struct rproc_vring *rvring;
c6aed238	75	struct fw_rsc_vdev *rsc;
ac8954a4 OBC	76	struct virtqueue *vq;
ac8954a4 OBC	77	void *addr;
a863af5d	78	int len, size;
ac8954a4	79
7a186941 OBC	80	/* we're temporarily limited to two virtqueues per rvdev */
	81	if (id >= ARRAY_SIZE(rvdev->vring))
	82	return ERR_PTR(-EINVAL);
	83
6457f126 MT	84	if (!name)
	85	return NULL;
	86
c6aed238 LP	87	/* Search allocated memory region by name */
	88	mem = rproc_find_carveout_by_name(rproc, "vdev%dvring%d", rvdev->index,
	89	id);
	90	if (!mem \|\| !mem->va)
	91	return ERR_PTR(-ENOMEM);
	92
6db20ea8	93	rvring = &rvdev->vring[id];
c6aed238	94	addr = mem->va;
7a186941	95	len = rvring->len;
ac8954a4	96
7a186941 OBC	97	/* zero vring */
	98	size = vring_size(len, rvring->align);
	99	memset(addr, 0, size);
ac8954a4	100
276ec993	101	dev_dbg(dev, "vring%d: va %pK qsz %d notifyid %d\n",
730f84ce	102	id, addr, len, rvring->notifyid);
ac8954a4	103
dd6da1c5 OBC	104	/*
	105	* Create the new vq, and tell virtio we're not interested in
	106	* the 'weak' smp barriers, since we're talking with a real device.
	107	*/
f94682dd MT	108	vq = vring_new_virtqueue(id, len, rvring->align, vdev, false, ctx,
f94682dd MT	109	addr, rproc_virtio_notify, callback, name);
ac8954a4	110	if (!vq) {
b5ab5e24	111	dev_err(dev, "vring_new_virtqueue %s failed\n", name);
6db20ea8	112	rproc_free_vring(rvring);
7a186941	113	return ERR_PTR(-ENOMEM);
ac8954a4 OBC	114	}
ac8954a4 OBC	115
7a186941 OBC	116	rvring->vq = vq;
7a186941 OBC	117	vq->priv = rvring;
ac8954a4	118
c6aed238 LP	119	/* Update vring in resource table */
	120	rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
	121	rsc->vring[id].da = mem->da;
	122
ac8954a4	123	return vq;
ac8954a4 OBC	124	}
ac8954a4 OBC	125
dab55bba	126	static void __rproc_virtio_del_vqs(struct virtio_device *vdev)
ac8954a4 OBC	127	{
ac8954a4 OBC	128	struct virtqueue vq, n;
7a186941	129	struct rproc_vring *rvring;
ac8954a4 OBC	130
ac8954a4 OBC	131	list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
7a186941 OBC	132	rvring = vq->priv;
7a186941 OBC	133	rvring->vq = NULL;
ac8954a4	134	vring_del_virtqueue(vq);
ac8954a4	135	}
ac8954a4 OBC	136	}
ac8954a4 OBC	137
dab55bba OBC	138	static void rproc_virtio_del_vqs(struct virtio_device *vdev)
dab55bba OBC	139	{
dab55bba OBC	140	__rproc_virtio_del_vqs(vdev);
	141	}
	142
f145928d	143	static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
730f84ce AS	144	struct virtqueue *vqs[],
730f84ce AS	145	vq_callback_t *callbacks[],
fb5e31d9	146	const char * const names[],
f94682dd	147	const bool * ctx,
fb5e31d9	148	struct irq_affinity *desc)
ac8954a4	149	{
a229989d	150	int i, ret, queue_idx = 0;
ac8954a4	151
ac8954a4	152	for (i = 0; i < nvqs; ++i) {
a229989d WW	153	if (!names[i]) {
	154	vqs[i] = NULL;
	155	continue;
	156	}
	157
	158	vqs[i] = rp_find_vq(vdev, queue_idx++, callbacks[i], names[i],
f94682dd	159	ctx ? ctx[i] : false);
ac8954a4 OBC	160	if (IS_ERR(vqs[i])) {
	161	ret = PTR_ERR(vqs[i]);
	162	goto error;
	163	}
	164	}
	165
	166	return 0;
	167
	168	error:
dab55bba	169	__rproc_virtio_del_vqs(vdev);
ac8954a4 OBC	170	return ret;
	171	}
	172
ac8954a4 OBC	173	static u8 rproc_virtio_get_status(struct virtio_device *vdev)
ac8954a4 OBC	174	{
92b38f85 SB	175	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
	176	struct fw_rsc_vdev *rsc;
	177
	178	rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
	179
	180	return rsc->status;
ac8954a4 OBC	181	}
	182
	183	static void rproc_virtio_set_status(struct virtio_device *vdev, u8 status)
	184	{
92b38f85 SB	185	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
	186	struct fw_rsc_vdev *rsc;
	187
	188	rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
	189
	190	rsc->status = status;
7a186941	191	dev_dbg(&vdev->dev, "status: %d\n", status);
ac8954a4 OBC	192	}
	193
	194	static void rproc_virtio_reset(struct virtio_device *vdev)
	195	{
92b38f85 SB	196	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
	197	struct fw_rsc_vdev *rsc;
	198
	199	rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
	200
	201	rsc->status = 0;
ac8954a4 OBC	202	dev_dbg(&vdev->dev, "reset !\n");
	203	}
	204
	205	/* provide the vdev features as retrieved from the firmware */
d0254773	206	static u64 rproc_virtio_get_features(struct virtio_device *vdev)
ac8954a4	207	{
7a186941	208	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
92b38f85 SB	209	struct fw_rsc_vdev *rsc;
	210
	211	rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
ac8954a4	212
92b38f85	213	return rsc->dfeatures;
ac8954a4 OBC	214	}
ac8954a4 OBC	215
3a814fdf TB	216	static void rproc_transport_features(struct virtio_device *vdev)
	217	{
	218	/*
	219	* Packed ring isn't enabled on remoteproc for now,
	220	* because remoteproc uses vring_new_virtqueue() which
	221	* creates virtio rings on preallocated memory.
	222	*/
	223	__virtio_clear_bit(vdev, VIRTIO_F_RING_PACKED);
	224	}
	225
5c609a5e	226	static int rproc_virtio_finalize_features(struct virtio_device *vdev)
ac8954a4	227	{
7a186941	228	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
92b38f85 SB	229	struct fw_rsc_vdev *rsc;
	230
	231	rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
ac8954a4 OBC	232
	233	/* Give virtio_ring a chance to accept features */
	234	vring_transport_features(vdev);
	235
3a814fdf TB	236	/* Give virtio_rproc a chance to accept features. */
	237	rproc_transport_features(vdev);
	238
93d389f8 MT	239	/* Make sure we don't have any features > 32 bits! */
	240	BUG_ON((u32)vdev->features != vdev->features);
	241
ac8954a4 OBC	242	/*
	243	* Remember the finalized features of our vdev, and provide it
	244	* to the remote processor once it is powered on.
ac8954a4	245	*/
e16e12be	246	rsc->gfeatures = vdev->features;
5c609a5e MT	247
5c609a5e MT	248	return 0;
92b38f85 SB	249	}
92b38f85 SB	250
f145928d AS	251	static void rproc_virtio_get(struct virtio_device *vdev, unsigned int offset,
f145928d AS	252	void *buf, unsigned int len)
92b38f85 SB	253	{
	254	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
	255	struct fw_rsc_vdev *rsc;
	256	void *cfg;
	257
	258	rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
	259	cfg = &rsc->vring[rsc->num_of_vrings];
	260
	261	if (offset + len > rsc->config_len \|\| offset + len < len) {
	262	dev_err(&vdev->dev, "rproc_virtio_get: access out of bounds\n");
	263	return;
	264	}
	265
	266	memcpy(buf, cfg + offset, len);
	267	}
	268
f145928d AS	269	static void rproc_virtio_set(struct virtio_device *vdev, unsigned int offset,
f145928d AS	270	const void *buf, unsigned int len)
92b38f85 SB	271	{
	272	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
	273	struct fw_rsc_vdev *rsc;
	274	void *cfg;
	275
	276	rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
	277	cfg = &rsc->vring[rsc->num_of_vrings];
	278
	279	if (offset + len > rsc->config_len \|\| offset + len < len) {
	280	dev_err(&vdev->dev, "rproc_virtio_set: access out of bounds\n");
	281	return;
	282	}
	283
	284	memcpy(cfg + offset, buf, len);
ac8954a4 OBC	285	}
ac8954a4 OBC	286
93503932	287	static const struct virtio_config_ops rproc_virtio_config_ops = {
ac8954a4 OBC	288	.get_features = rproc_virtio_get_features,
	289	.finalize_features = rproc_virtio_finalize_features,
	290	.find_vqs = rproc_virtio_find_vqs,
	291	.del_vqs = rproc_virtio_del_vqs,
	292	.reset = rproc_virtio_reset,
	293	.set_status = rproc_virtio_set_status,
	294	.get_status = rproc_virtio_get_status,
92b38f85 SB	295	.get = rproc_virtio_get,
92b38f85 SB	296	.set = rproc_virtio_set,
ac8954a4 OBC	297	};
	298
	299	/*
	300	* This function is called whenever vdev is released, and is responsible
7183a2a7	301	* to decrement the remote processor's refcount which was taken when vdev was
ac8954a4 OBC	302	* added.
	303	*
	304	* Never call this function directly; it will be called by the driver
	305	* core when needed.
	306	*/
aab8d802	307	static void rproc_virtio_dev_release(struct device *dev)
ac8954a4 OBC	308	{
ac8954a4 OBC	309	struct virtio_device *vdev = dev_to_virtio(dev);
6db20ea8	310	struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
ac8954a4 OBC	311	struct rproc *rproc = vdev_to_rproc(vdev);
ac8954a4 OBC	312
d4c036fe LP	313	kfree(vdev);
d4c036fe LP	314
aab8d802	315	kref_put(&rvdev->refcount, rproc_vdev_release);
6db20ea8	316
7183a2a7	317	put_device(&rproc->dev);
ac8954a4 OBC	318	}
	319
	320	/**
7a186941 OBC	321	* rproc_add_virtio_dev() - register an rproc-induced virtio device
7a186941 OBC	322	* @rvdev: the remote vdev
ac8954a4	323	*
7a186941 OBC	324	* This function registers a virtio device. This vdev's partent is
7a186941 OBC	325	* the rproc device.
ac8954a4	326	*
7a186941	327	* Returns 0 on success or an appropriate error value otherwise.
ac8954a4	328	*/
7a186941	329	int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
ac8954a4	330	{
7a186941	331	struct rproc *rproc = rvdev->rproc;
086d0872	332	struct device *dev = &rvdev->dev;
d4c036fe	333	struct virtio_device *vdev;
086d0872	334	struct rproc_mem_entry *mem;
ac8954a4 OBC	335	int ret;
ac8954a4 OBC	336
086d0872 LP	337	/* Try to find dedicated vdev buffer carveout */
	338	mem = rproc_find_carveout_by_name(rproc, "vdev%dbuffer", rvdev->index);
	339	if (mem) {
	340	phys_addr_t pa;
	341
	342	if (mem->of_resm_idx != -1) {
	343	struct device_node *np = rproc->dev.parent->of_node;
	344
	345	/* Associate reserved memory to vdev device */
	346	ret = of_reserved_mem_device_init_by_idx(dev, np,
	347	mem->of_resm_idx);
	348	if (ret) {
	349	dev_err(dev, "Can't associate reserved memory\n");
	350	goto out;
	351	}
	352	} else {
	353	if (mem->va) {
	354	dev_warn(dev, "vdev %d buffer already mapped\n",
	355	rvdev->index);
	356	pa = rproc_va_to_pa(mem->va);
	357	} else {
	358	/* Use dma address as carveout no memmapped yet */
	359	pa = (phys_addr_t)mem->dma;
	360	}
	361
	362	/* Associate vdev buffer memory pool to vdev subdev */
	363	ret = dma_declare_coherent_memory(dev, pa,
	364	mem->da,
d664ce75	365	mem->len);
086d0872 LP	366	if (ret < 0) {
	367	dev_err(dev, "Failed to associate buffer\n");
	368	goto out;
	369	}
	370	}
	371	}
	372
d4c036fe LP	373	/* Allocate virtio device */
	374	vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
	375	if (!vdev) {
	376	ret = -ENOMEM;
	377	goto out;
	378	}
7a186941 OBC	379	vdev->id.device = id,
	380	vdev->config = &rproc_virtio_config_ops,
	381	vdev->dev.parent = dev;
aab8d802	382	vdev->dev.release = rproc_virtio_dev_release;
ac8954a4 OBC	383
	384	/*
	385	* We're indirectly making a non-temporary copy of the rproc pointer
	386	* here, because drivers probed with this vdev will indirectly
	387	* access the wrapping rproc.
	388	*
	389	* Therefore we must increment the rproc refcount here, and decrement
	390	* it _only_ when the vdev is released.
	391	*/
7183a2a7	392	get_device(&rproc->dev);
ac8954a4	393
aab8d802 BA	394	/* Reference the vdev and vring allocations */
	395	kref_get(&rvdev->refcount);
	396
7a186941	397	ret = register_virtio_device(vdev);
ac8954a4	398	if (ret) {
900a163e	399	put_device(&vdev->dev);
ac8954a4	400	dev_err(dev, "failed to register vdev: %d\n", ret);
7a186941	401	goto out;
ac8954a4 OBC	402	}
ac8954a4 OBC	403
7a186941 OBC	404	dev_info(dev, "registered %s (type %d)\n", dev_name(&vdev->dev), id);
	405
	406	out:
ac8954a4 OBC	407	return ret;
	408	}
	409
	410	/**
7a186941	411	* rproc_remove_virtio_dev() - remove an rproc-induced virtio device
d4c036fe LP	412	* @dev: the virtio device
d4c036fe LP	413	* @data: must be null
ac8954a4	414	*
7a186941	415	* This function unregisters an existing virtio device.
ac8954a4	416	*/
d4c036fe	417	int rproc_remove_virtio_dev(struct device dev, void data)
ac8954a4	418	{
d4c036fe LP	419	struct virtio_device *vdev = dev_to_virtio(dev);
	420
	421	unregister_virtio_device(vdev);
	422	return 0;
ac8954a4	423	}