[PATCH v3] PCI: endpoint: Use EPC's device in dma_alloc_coherent/dma_free_coherent

From: Kishon Vijay Abraham I
Date: Thu Jan 11 2018 - 03:31:20 EST


After commit 723288836628bc1c08 ("of: restrict DMA configuration"),
of_dma_configure doesn't configure the coherent_dma_mask/dma_mask
of endpoint function device (since it doesn't have a dt node associated
with and hence no dma-ranges property), resulting in dma_alloc_coherent
(used in pci_epf_alloc_space) to fail.

Fix it by making dma_alloc_coherent use EPC's device for allocating
memory address.

Link: http://lkml.kernel.org/r/64d63468-d28f-8fcd-a6f3-cf2a6401c8cb@xxxxxx
Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Rob Herring <robh@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Tested-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxxxxxxxxxxx>
Tested-by: Niklas Cassel <niklas.cassel@xxxxxxxx>
Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>
---
Changes from v2:
No change in patch. Added "Link", "Reviewed-by" and "Tested-by" tags

Changes from v1:
No change in patch. Only added "Tested-by" of Cyrille Pitchen.

drivers/pci/endpoint/pci-epc-core.c | 10 ----------
drivers/pci/endpoint/pci-epf-core.c | 4 ++--
2 files changed, 2 insertions(+), 12 deletions(-)

diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index 42c2a1156325..cd7d4788b94d 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -18,7 +18,6 @@
*/

#include <linux/device.h>
-#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/of_device.h>
@@ -371,7 +370,6 @@ EXPORT_SYMBOL_GPL(pci_epc_write_header);
int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf)
{
unsigned long flags;
- struct device *dev = epc->dev.parent;

if (epf->epc)
return -EBUSY;
@@ -383,12 +381,6 @@ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf)
return -EINVAL;

epf->epc = epc;
- if (dev->of_node) {
- of_dma_configure(&epf->dev, dev->of_node);
- } else {
- dma_set_coherent_mask(&epf->dev, epc->dev.coherent_dma_mask);
- epf->dev.dma_mask = epc->dev.dma_mask;
- }

spin_lock_irqsave(&epc->lock, flags);
list_add_tail(&epf->list, &epc->pci_epf);
@@ -503,9 +495,7 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops,
INIT_LIST_HEAD(&epc->pci_epf);

device_initialize(&epc->dev);
- dma_set_coherent_mask(&epc->dev, dev->coherent_dma_mask);
epc->dev.class = pci_epc_class;
- epc->dev.dma_mask = dev->dma_mask;
epc->dev.parent = dev;
epc->ops = ops;

diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
index ae1611a62808..95ccc4b8a0a2 100644
--- a/drivers/pci/endpoint/pci-epf-core.c
+++ b/drivers/pci/endpoint/pci-epf-core.c
@@ -99,7 +99,7 @@ EXPORT_SYMBOL_GPL(pci_epf_bind);
*/
void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar)
{
- struct device *dev = &epf->dev;
+ struct device *dev = epf->epc->dev.parent;

if (!addr)
return;
@@ -122,7 +122,7 @@ EXPORT_SYMBOL_GPL(pci_epf_free_space);
void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar)
{
void *space;
- struct device *dev = &epf->dev;
+ struct device *dev = epf->epc->dev.parent;
dma_addr_t phys_addr;

if (size < 128)
--
2.11.0