diff options
Diffstat (limited to 'drivers/rpmsg/virtio_rpmsg_bus.c')
| -rw-r--r-- | drivers/rpmsg/virtio_rpmsg_bus.c | 44 |
1 files changed, 30 insertions, 14 deletions
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c index b6135d4d54eb..92f6af6da699 100644 --- a/drivers/rpmsg/virtio_rpmsg_bus.c +++ b/drivers/rpmsg/virtio_rpmsg_bus.c @@ -41,6 +41,7 @@ * @svq: tx virtqueue * @rbufs: kernel address of rx buffers * @sbufs: kernel address of tx buffers + * @num_bufs: total number of buffers for rx and tx * @last_sbuf: index of last tx buffer used * @bufs_dma: dma base addr of the buffers * @tx_lock: protects svq, sbufs and sleepers, to allow concurrent senders. @@ -60,6 +61,7 @@ struct virtproc_info { struct virtio_device *vdev; struct virtqueue *rvq, *svq; void *rbufs, *sbufs; + unsigned int num_bufs; int last_sbuf; dma_addr_t bufs_dma; struct mutex tx_lock; @@ -86,13 +88,14 @@ struct rpmsg_channel_info { #define to_rpmsg_driver(d) container_of(d, struct rpmsg_driver, drv) /* - * We're allocating 512 buffers of 512 bytes for communications, and then - * using the first 256 buffers for RX, and the last 256 buffers for TX. + * We're allocating buffers of 512 bytes each for communications. The + * number of buffers will be computed from the number of buffers supported + * by the vring, upto a maximum of 512 buffers (256 in each direction). * * Each buffer will have 16 bytes for the msg header and 496 bytes for * the payload. * - * This will require a total space of 256KB for the buffers. + * This will utilize a maximum total space of 256KB for the buffers. * * We might also want to add support for user-provided buffers in time. * This will allow bigger buffer size flexibility, and can also be used @@ -102,9 +105,8 @@ struct rpmsg_channel_info { * can change this without changing anything in the firmware of the remote * processor. */ -#define RPMSG_NUM_BUFS (512) +#define MAX_RPMSG_NUM_BUFS (512) #define RPMSG_BUF_SIZE (512) -#define RPMSG_TOTAL_BUF_SPACE (RPMSG_NUM_BUFS * RPMSG_BUF_SIZE) /* * Local addresses are dynamically allocated on-demand. @@ -579,7 +581,7 @@ static void *get_a_tx_buf(struct virtproc_info *vrp) * either pick the next unused tx buffer * (half of our buffers are used for sending messages) */ - if (vrp->last_sbuf < RPMSG_NUM_BUFS / 2) + if (vrp->last_sbuf < vrp->num_bufs / 2) ret = vrp->sbufs + RPMSG_BUF_SIZE * vrp->last_sbuf++; /* or recycle a used one */ else @@ -948,6 +950,7 @@ static int rpmsg_probe(struct virtio_device *vdev) struct virtproc_info *vrp; void *bufs_va; int err = 0, i; + size_t total_buf_space; vrp = kzalloc(sizeof(*vrp), GFP_KERNEL); if (!vrp) @@ -968,10 +971,22 @@ static int rpmsg_probe(struct virtio_device *vdev) vrp->rvq = vqs[0]; vrp->svq = vqs[1]; + /* we expect symmetric tx/rx vrings */ + WARN_ON(virtqueue_get_vring_size(vrp->rvq) != + virtqueue_get_vring_size(vrp->svq)); + + /* we need less buffers if vrings are small */ + if (virtqueue_get_vring_size(vrp->rvq) < MAX_RPMSG_NUM_BUFS / 2) + vrp->num_bufs = virtqueue_get_vring_size(vrp->rvq) * 2; + else + vrp->num_bufs = MAX_RPMSG_NUM_BUFS; + + total_buf_space = vrp->num_bufs * RPMSG_BUF_SIZE; + /* allocate coherent memory for the buffers */ bufs_va = dma_alloc_coherent(vdev->dev.parent->parent, - RPMSG_TOTAL_BUF_SPACE, - &vrp->bufs_dma, GFP_KERNEL); + total_buf_space, &vrp->bufs_dma, + GFP_KERNEL); if (!bufs_va) { err = -ENOMEM; goto vqs_del; @@ -984,10 +999,10 @@ static int rpmsg_probe(struct virtio_device *vdev) vrp->rbufs = bufs_va; /* and half is dedicated for TX */ - vrp->sbufs = bufs_va + RPMSG_TOTAL_BUF_SPACE / 2; + vrp->sbufs = bufs_va + total_buf_space / 2; /* set up the receive buffers */ - for (i = 0; i < RPMSG_NUM_BUFS / 2; i++) { + for (i = 0; i < vrp->num_bufs / 2; i++) { struct scatterlist sg; void *cpu_addr = vrp->rbufs + i * RPMSG_BUF_SIZE; @@ -1023,8 +1038,8 @@ static int rpmsg_probe(struct virtio_device *vdev) return 0; free_coherent: - dma_free_coherent(vdev->dev.parent->parent, RPMSG_TOTAL_BUF_SPACE, - bufs_va, vrp->bufs_dma); + dma_free_coherent(vdev->dev.parent->parent, total_buf_space, + bufs_va, vrp->bufs_dma); vqs_del: vdev->config->del_vqs(vrp->vdev); free_vrp: @@ -1042,6 +1057,7 @@ static int rpmsg_remove_device(struct device *dev, void *data) static void rpmsg_remove(struct virtio_device *vdev) { struct virtproc_info *vrp = vdev->priv; + size_t total_buf_space = vrp->num_bufs * RPMSG_BUF_SIZE; int ret; vdev->config->reset(vdev); @@ -1057,8 +1073,8 @@ static void rpmsg_remove(struct virtio_device *vdev) vdev->config->del_vqs(vrp->vdev); - dma_free_coherent(vdev->dev.parent->parent, RPMSG_TOTAL_BUF_SPACE, - vrp->rbufs, vrp->bufs_dma); + dma_free_coherent(vdev->dev.parent->parent, total_buf_space, + vrp->rbufs, vrp->bufs_dma); kfree(vrp); } |