linux/drivers/remoteproc/remoteproc_virtio.c
Uwe Kleine-König d1d8d4428c remoteproc: virtio: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230504194453.1150368-16-u.kleine-koenig@pengutronix.de
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
2023-05-09 13:36:32 -06:00

602 lines
15 KiB
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-direct.h>
#include <linux/dma-map-ops.h>
#include <linux/dma-mapping.h>
#include <linux/export.h>
#include <linux/of_reserved_mem.h>
#include <linux/platform_device.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"
static int copy_dma_range_map(struct device *to, struct device *from)
{
const struct bus_dma_region *map = from->dma_range_map, *new_map, *r;
int num_ranges = 0;
if (!map)
return 0;
for (r = map; r->size; r++)
num_ranges++;
new_map = kmemdup(map, array_size(num_ranges + 1, sizeof(*map)),
GFP_KERNEL);
if (!new_map)
return -ENOMEM;
to->dma_range_map = new_map;
return 0;
}
static struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev)
{
struct platform_device *pdev;
pdev = container_of(vdev->dev.parent, struct platform_device, dev);
return platform_get_drvdata(pdev);
}
static struct rproc *vdev_to_rproc(struct virtio_device *vdev)
{
struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
return rvdev->rproc;
}
/* 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.
*
* Return: 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 num, 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;
num = rvring->num;
/* zero vring */
size = vring_size(num, rvring->align);
memset(addr, 0, size);
dev_dbg(dev, "vring%d: va %pK qsz %d notifyid %d\n",
id, addr, num, 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, num, 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);
}
vq->num_max = num;
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);
kfree(vdev);
put_device(&rvdev->pdev->dev);
}
/**
* rproc_add_virtio_dev() - register an rproc-induced virtio device
* @rvdev: the remote vdev
* @id: the device type identification (used to match it with a driver).
*
* This function registers a virtio device. This vdev's partent is
* the rproc device.
*
* Return: 0 on success or an appropriate error value otherwise
*/
static int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
{
struct rproc *rproc = rvdev->rproc;
struct device *dev = &rvdev->pdev->dev;
struct virtio_device *vdev;
struct rproc_mem_entry *mem;
int ret;
if (rproc->ops->kick == NULL) {
ret = -EINVAL;
dev_err(dev, ".kick method not defined for %s\n", rproc->name);
goto out;
}
/* 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;
}
}
} else {
struct device_node *np = rproc->dev.parent->of_node;
/*
* If we don't have dedicated buffer, just attempt to re-assign
* the reserved memory from our parent. A default memory-region
* at index 0 from the parent's memory-regions is assigned for
* the rvdev dev to allocate from. Failure is non-critical and
* the allocations will fall back to global pools, so don't
* check return value either.
*/
of_reserved_mem_device_init_by_idx(dev, np, 0);
}
/* 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;
/* Reference the vdev and vring allocations */
get_device(dev);
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.
*
* Return: 0
*/
static int rproc_remove_virtio_dev(struct device *dev, void *data)
{
struct virtio_device *vdev = dev_to_virtio(dev);
unregister_virtio_device(vdev);
return 0;
}
static int rproc_vdev_do_start(struct rproc_subdev *subdev)
{
struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
return rproc_add_virtio_dev(rvdev, rvdev->id);
}
static void rproc_vdev_do_stop(struct rproc_subdev *subdev, bool crashed)
{
struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
struct device *dev = &rvdev->pdev->dev;
int ret;
ret = device_for_each_child(dev, NULL, rproc_remove_virtio_dev);
if (ret)
dev_warn(dev, "can't remove vdev child device: %d\n", ret);
}
static int rproc_virtio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct rproc_vdev_data *rvdev_data = dev->platform_data;
struct rproc_vdev *rvdev;
struct rproc *rproc = container_of(dev->parent, struct rproc, dev);
struct fw_rsc_vdev *rsc;
int i, ret;
if (!rvdev_data)
return -EINVAL;
rvdev = devm_kzalloc(dev, sizeof(*rvdev), GFP_KERNEL);
if (!rvdev)
return -ENOMEM;
rvdev->id = rvdev_data->id;
rvdev->rproc = rproc;
rvdev->index = rvdev_data->index;
ret = copy_dma_range_map(dev, rproc->dev.parent);
if (ret)
return ret;
/* Make device dma capable by inheriting from parent's capabilities */
set_dma_ops(dev, get_dma_ops(rproc->dev.parent));
ret = dma_coerce_mask_and_coherent(dev, dma_get_mask(rproc->dev.parent));
if (ret) {
dev_warn(dev, "Failed to set DMA mask %llx. Trying to continue... (%pe)\n",
dma_get_mask(rproc->dev.parent), ERR_PTR(ret));
}
platform_set_drvdata(pdev, rvdev);
rvdev->pdev = pdev;
rsc = rvdev_data->rsc;
/* parse the vrings */
for (i = 0; i < rsc->num_of_vrings; i++) {
ret = rproc_parse_vring(rvdev, rsc, i);
if (ret)
return ret;
}
/* remember the resource offset*/
rvdev->rsc_offset = rvdev_data->rsc_offset;
/* allocate the vring resources */
for (i = 0; i < rsc->num_of_vrings; i++) {
ret = rproc_alloc_vring(rvdev, i);
if (ret)
goto unwind_vring_allocations;
}
rproc_add_rvdev(rproc, rvdev);
rvdev->subdev.start = rproc_vdev_do_start;
rvdev->subdev.stop = rproc_vdev_do_stop;
rproc_add_subdev(rproc, &rvdev->subdev);
/*
* We're indirectly making a non-temporary copy of the rproc pointer
* here, because the platform device or the vdev device will indirectly
* access the wrapping rproc.
*
* Therefore we must increment the rproc refcount here, and decrement
* it _only_ on platform remove.
*/
get_device(&rproc->dev);
return 0;
unwind_vring_allocations:
for (i--; i >= 0; i--)
rproc_free_vring(&rvdev->vring[i]);
return ret;
}
static void rproc_virtio_remove(struct platform_device *pdev)
{
struct rproc_vdev *rvdev = dev_get_drvdata(&pdev->dev);
struct rproc *rproc = rvdev->rproc;
struct rproc_vring *rvring;
int id;
for (id = 0; id < ARRAY_SIZE(rvdev->vring); id++) {
rvring = &rvdev->vring[id];
rproc_free_vring(rvring);
}
rproc_remove_subdev(rproc, &rvdev->subdev);
rproc_remove_rvdev(rvdev);
of_reserved_mem_device_release(&pdev->dev);
dma_release_coherent_memory(&pdev->dev);
put_device(&rproc->dev);
}
/* Platform driver */
static struct platform_driver rproc_virtio_driver = {
.probe = rproc_virtio_probe,
.remove_new = rproc_virtio_remove,
.driver = {
.name = "rproc-virtio",
},
};
builtin_platform_driver(rproc_virtio_driver);