From: Martyn Welch <martyn.welch@xxxxxxxxxxx>
Check the directions in which the DMA controller is expected to operate
before giving control of a resource.
Signed-off-by: Martyn Welch <martyn.welch@xxxxxxxxxxx>
---
drivers/staging/vme/TODO | 22 ----------------------
drivers/staging/vme/bridges/vme_ca91cx42.c | 2 ++
drivers/staging/vme/bridges/vme_tsi148.c | 4 ++++
drivers/staging/vme/vme.c | 8 +++++---
drivers/staging/vme/vme.h | 10 +++++++++-
drivers/staging/vme/vme_api.txt | 27 +++++++++++++++++++--------
drivers/staging/vme/vme_bridge.h | 1 +
7 files changed, 40 insertions(+), 34 deletions(-)
diff --git a/drivers/staging/vme/TODO b/drivers/staging/vme/TODO
index 2201ff6..bdc5f62 100644
--- a/drivers/staging/vme/TODO
+++ b/drivers/staging/vme/TODO
@@ -4,28 +4,6 @@
API
===
-DMA Resource Allocation incomplete
-----------------------------------
-
-The current DMA resource Allocation provides no means of selecting the
-suitability of a DMA controller based on it's supported modes of operation, as
-opposed to the resource allocation mechanisms for master and slave windows:
-
- struct vme_resource *vme_dma_request(struct device *dev);
-
-As opposed to:
-
- struct vme_resource * vme_master_request(struct device *dev,
- vme_address_t aspace, vme_cycle_t cycle, vme_width_t width);
-
-The TSI148 can perform, VME-to-PCI, PCI-to-VME, PATTERN-to-VME, PATTERN-to-PCI,
-VME-to-VME and PCI-to-PCI transfers. The CA91C142 can only provide VME-to-PCI
-and PCI-to-VME.
-
-Add a mechanism to select a VME controller based on source/target type,
-required aspace, cycle and width requirements.
-
-
Master window broadcast select mask
-----------------------------------
diff --git a/drivers/staging/vme/bridges/vme_ca91cx42.c b/drivers/staging/vme/bridges/vme_ca91cx42.c
index 272cc26..7eaba35 100644
--- a/drivers/staging/vme/bridges/vme_ca91cx42.c
+++ b/drivers/staging/vme/bridges/vme_ca91cx42.c
@@ -1109,6 +1109,8 @@ static int ca91cx42_probe(struct pci_dev *pdev, const struct pci_device_id *id)
mutex_init(&(dma_ctrlr->mtx));
dma_ctrlr->locked = 0;
dma_ctrlr->number = i;
+ dma_ctrlr->route_attr = VME_DMA_VME_TO_MEM |
+ VME_DMA_MEM_TO_VME;
INIT_LIST_HEAD(&(dma_ctrlr->pending));
INIT_LIST_HEAD(&(dma_ctrlr->running));
list_add_tail(&(dma_ctrlr->list),
diff --git a/drivers/staging/vme/bridges/vme_tsi148.c b/drivers/staging/vme/bridges/vme_tsi148.c
index 2ca5126..e74c4a9 100644
--- a/drivers/staging/vme/bridges/vme_tsi148.c
+++ b/drivers/staging/vme/bridges/vme_tsi148.c
@@ -2421,6 +2421,10 @@ static int tsi148_probe(struct pci_dev *pdev, const struct pci_device_id *id)
mutex_init(&(dma_ctrlr->mtx));
dma_ctrlr->locked = 0;
dma_ctrlr->number = i;
+ dma_ctrlr->route_attr = VME_DMA_VME_TO_MEM |
+ VME_DMA_MEM_TO_VME | VME_DMA_VME_TO_VME |
+ VME_DMA_MEM_TO_MEM | VME_DMA_PATTERN_TO_VME |
+ VME_DMA_PATTERN_TO_MEM;
INIT_LIST_HEAD(&(dma_ctrlr->pending));
INIT_LIST_HEAD(&(dma_ctrlr->running));
list_add_tail(&(dma_ctrlr->list),
diff --git a/drivers/staging/vme/vme.c b/drivers/staging/vme/vme.c
index 8d8f9cb..79c501d 100644
--- a/drivers/staging/vme/vme.c
+++ b/drivers/staging/vme/vme.c
@@ -643,7 +643,7 @@ EXPORT_SYMBOL(vme_master_free);
* Request a DMA controller with specific attributes, return some unique
* identifier.
*/
-struct vme_resource *vme_dma_request(struct device *dev)
+struct vme_resource *vme_dma_request(struct device *dev, vme_dma_route_t route)
{
struct vme_bridge *bridge;
struct list_head *dma_pos = NULL;
@@ -670,9 +670,11 @@ struct vme_resource *vme_dma_request(struct device *dev)
continue;
}
- /* Find an unlocked controller */
+ /* Find an unlocked and compatible controller */
mutex_lock(&(dma_ctrlr->mtx));
- if (dma_ctrlr->locked == 0) {
+ if (((dma_ctrlr->route_attr & route) == route) &&
+ (dma_ctrlr->locked == 0)) {
+
dma_ctrlr->locked = 1;
mutex_unlock(&(dma_ctrlr->mtx));
allocated_ctrlr = dma_ctrlr;
diff --git a/drivers/staging/vme/vme.h b/drivers/staging/vme/vme.h
index 5a4d163..48768ca 100644
--- a/drivers/staging/vme/vme.h
+++ b/drivers/staging/vme/vme.h
@@ -68,6 +68,14 @@ typedef u32 vme_pattern_t;
#define VME_DMA_PATTERN_WORD (1<<1)
#define VME_DMA_PATTERN_INCREMENT (1<<2)
+typedef u32 vme_dma_route_t;
+#define VME_DMA_VME_TO_MEM (1<<0)
+#define VME_DMA_MEM_TO_VME (1<<1)
+#define VME_DMA_VME_TO_VME (1<<2)
+#define VME_DMA_MEM_TO_MEM (1<<3)
+#define VME_DMA_PATTERN_TO_VME (1<<4)
+#define VME_DMA_PATTERN_TO_MEM (1<<5)
+
struct vme_dma_attr {
vme_dma_t type;
void *private;
@@ -124,7 +132,7 @@ unsigned int vme_master_rmw(struct vme_resource *, unsigned int, unsigned int,
unsigned int, loff_t);
void vme_master_free(struct vme_resource *);
-struct vme_resource *vme_dma_request(struct device *);
+struct vme_resource *vme_dma_request(struct device *, vme_dma_route_t);
struct vme_dma_list *vme_new_dma_list(struct vme_resource *);
struct vme_dma_attr *vme_dma_pattern_attribute(u32, vme_pattern_t);
struct vme_dma_attr *vme_dma_pci_attribute(dma_addr_t);
diff --git a/drivers/staging/vme/vme_api.txt b/drivers/staging/vme/vme_api.txt
index a5c1b1c..a910a0c 100644
--- a/drivers/staging/vme/vme_api.txt
+++ b/drivers/staging/vme/vme_api.txt
@@ -77,16 +77,21 @@ driver in question:
struct vme_resource * vme_slave_request(struct device *dev,
vme_address_t aspace, vme_cycle_t cycle);
- struct vme_resource *vme_dma_request(struct device *dev);
+ struct vme_resource *vme_dma_request(struct device *dev,
+ vme_dma_route_t route);
For slave windows these attributes are split into those of type 'vme_address_t'
-and 'vme_cycle_t'. Master windows add a further set of attributes 'vme_cycle_t'.
-These attributes are defined as bitmasks and as such any combination of the
-attributes can be requested for a single window, the core will assign a window
-that meets the requirements, returning a pointer of type vme_resource that
-should be used to identify the allocated resource when it is used. If an
-unallocated window fitting the requirements can not be found a NULL pointer will
-be returned.
+and 'vme_cycle_t'. Master windows add a further set of attributes
+'vme_cycle_t'. These attributes are defined as bitmasks and as such any
+combination of the attributes can be requested for a single window, the core
+will assign a window that meets the requirements, returning a pointer of type
+vme_resource that should be used to identify the allocated resource when it is
+used. For DMA controllers, the request function requires the potential
+direction of any transfers to be provided in the route attributes. This is
+typically VME-to-MEM and/or MEM-to-VME, though some hardware can support
+VME-to-VME and MEM-to-MEM transfers as well as test pattern generation. If an
+unallocated window fitting the requirements can not be found a NULL pointer
+will be returned.
Functions are also provided to free window allocations once they are no longer
required. These functions should be passed the pointer to the resource provided
@@ -237,6 +242,12 @@ covered under "Transfer Attributes"):
struct vme_dma_attr *src, struct vme_dma_attr *dest,
size_t count);
+NOTE: The detailed attributes of the transfers source and destination
+ are not checked until an entry is added to a DMA list, the request
+ for a DMA channel purely checks the directions in which the
+ controller is expected to transfer data. As a result it is
+ possible for this call to return an error, for example if the
+ source or destination is in an unsupported VME address space.
Transfer Attributes
-------------------
diff --git a/drivers/staging/vme/vme_bridge.h b/drivers/staging/vme/vme_bridge.h
index 92e5614..f8ead21 100644
--- a/drivers/staging/vme/vme_bridge.h
+++ b/drivers/staging/vme/vme_bridge.h
@@ -64,6 +64,7 @@ struct vme_dma_resource {
int number;
struct list_head pending;
struct list_head running;
+ vme_dma_route_t route_attr;
};
struct vme_lm_resource {
--
Martyn Welch (Principal Software Engineer) | Registered in England and
GE Intelligent Platforms | Wales (3828642) at 100
T +44(0)127322748 | Barbirolli Square, Manchester,
E martyn.welch@xxxxxx | M2 3AB VAT:GB 927559189
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