[PATCH 6/7] remoteproc: modify vring allocation to support preallocated region

From: Loic Pallardy
Date: Fri Oct 27 2017 - 08:45:08 EST


Current version of rproc_alloc_vring function supports only dynamic vring
allocation.
This patch extends rproc_alloc_vring to verify if requested vring DA is
already part or not of a registered carveout. If true, nothing to do, else
just allocate vring as before.

Signed-off-by: Loic Pallardy <loic.pallardy@xxxxxx>
---
drivers/remoteproc/remoteproc_core.c | 50 +++++++++++++++++++++++-------------
1 file changed, 32 insertions(+), 18 deletions(-)

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 515a17a..e1dbe65 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -263,21 +263,41 @@ int rproc_alloc_vring(struct rproc_vdev *rvdev, int i)
struct device *dev = &rproc->dev;
struct rproc_vring *rvring = &rvdev->vring[i];
struct fw_rsc_vdev *rsc;
- dma_addr_t dma;
+ dma_addr_t dma = 0;
void *va;
int ret, size, notifyid;

/* actual size of vring (in bytes) */
size = PAGE_ALIGN(vring_size(rvring->len, rvring->align));

- /*
- * Allocate non-cacheable memory for the vring. In the future
- * this call will also configure the IOMMU for us
- */
- va = dma_alloc_coherent(dev->parent, size, &dma, GFP_KERNEL);
- if (!va) {
- dev_err(dev->parent, "dma_alloc_coherent failed\n");
- return -EINVAL;
+ /* get vring resource table pointer */
+ rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
+
+ if (rsc->vring[i].da != FW_RSC_ADDR_ANY) {
+ va = rproc_find_carveout_by_da(rproc, rsc->vring[i].da, size);
+
+ if (!va) {
+ /* No region not found */
+ dev_err(dev->parent, "Pre-allocated vring not found\n");
+ return -ENOMEM;
+ }
+ } else {
+ /*
+ * Allocate non-cacheable memory for the vring. In the future
+ * this call will also configure the IOMMU for us
+ */
+ va = dma_alloc_coherent(dev->parent, size, &dma, GFP_KERNEL);
+ if (!va) {
+ dev_err(dev->parent, "dma_alloc_coherent failed\n");
+ return -EINVAL;
+ }
+ /*
+ * Let the rproc know the da of this vring.
+ * Not all platforms use dma_alloc_coherent to automatically
+ * set up the iommu. In this case the device address (da) will
+ * hold the physical address and not the device address.
+ */
+ rsc->vring[i].da = dma;
}

/*
@@ -304,14 +324,7 @@ int rproc_alloc_vring(struct rproc_vdev *rvdev, int i)
rvring->dma = dma;
rvring->notifyid = notifyid;

- /*
- * Let the rproc know the notifyid and da of this vring.
- * Not all platforms use dma_alloc_coherent to automatically
- * set up the iommu. In this case the device address (da) will
- * hold the physical address and not the device address.
- */
- rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
- rsc->vring[i].da = dma;
+ /* Let the rproc know the notifyid of this vring. */
rsc->vring[i].notifyid = notifyid;
return 0;
}
@@ -348,7 +361,8 @@ void rproc_free_vring(struct rproc_vring *rvring)
int idx = rvring->rvdev->vring - rvring;
struct fw_rsc_vdev *rsc;

- dma_free_coherent(rproc->dev.parent, size, rvring->va, rvring->dma);
+ if (rvring->dma)
+ dma_free_coherent(rproc->dev.parent, size, rvring->va, rvring->dma);
idr_remove(&rproc->notifyids, rvring->notifyid);

/* reset resource entry info */
--
1.9.1