dmaengine: ti: k3-udma: Add glue layer for non DMAengine users

Certain users can not use right now the DMAengine API due to missing
features in the core. Prime example is Networking.

These users can use the glue layer interface to avoid misuse of DMAengine
API and when the core gains the needed features they can be converted to
use generic API.

The most prominent features the glue layer clients are depending on:

- most PSI-L native peripheral use extra rflow ranges on a receive channel
   and depending on the peripheral's configuration packets from a single
   free descriptor ring is going to be received to different receive ring
  - it is also possible to have different free descriptor rings per rflow
    and an rflow can also support 4 additional free descriptor ring based
    on the size of the incoming packet
- out of order completion of descriptors on a channel
 - when we have several queues to handle different priority packets the
   descriptors will be completed 'out-of-order'
- the notion of prep_slave_sg is not matching with what the streaming type
   of operation is demanding for networking
- Streaming type of operation
 - Ability to fill the free descriptor ring with descriptors in
   anticipation of incoming traffic and when a packet arrives UDMAP will
   form a packet and gives it to the client driver
 - the descriptors are not backed with exact size data buffers as we don't
   know the size of the packet we will receive, but as a generic pool of
   buffers to be used by the receive channel
- NAPI type of operation (polling instead of interrupt driven transfer)
 - without this we can not sustain gigabit speeds and we need to support NAPI
 - not to limit this to networking, but other high performance operations

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Keerthy <j-keerthy@ti.com>
Link: https://lore.kernel.org/r/20191223110458.30766-12-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 31 insertions, 0 deletions

diff --git a/drivers/dma/ti/k3-udma.h b/drivers/dma/ti/k3-udma.h
index ff428f823e67..128d8744a435 100644
--- a/drivers/dma/ti/k3-udma.h
+++ b/drivers/dma/ti/k3-udma.h
@@ -117,4 +117,35 @@ struct udma_tisci_rm {
 	struct ti_sci_resource *rm_ranges[RM_RANGE_LAST];
 };
 
+/* Direct access to UDMA low lever resources for the glue layer */
+int xudma_navss_psil_pair(struct udma_dev *ud, u32 src_thread, u32 dst_thread);
+int xudma_navss_psil_unpair(struct udma_dev *ud, u32 src_thread,
+			    u32 dst_thread);
+
+struct udma_dev *of_xudma_dev_get(struct device_node *np, const char *property);
+void xudma_dev_put(struct udma_dev *ud);
+u32 xudma_dev_get_psil_base(struct udma_dev *ud);
+struct udma_tisci_rm *xudma_dev_get_tisci_rm(struct udma_dev *ud);
+
+int xudma_alloc_gp_rflow_range(struct udma_dev *ud, int from, int cnt);
+int xudma_free_gp_rflow_range(struct udma_dev *ud, int from, int cnt);
+
+struct udma_tchan *xudma_tchan_get(struct udma_dev *ud, int id);
+struct udma_rchan *xudma_rchan_get(struct udma_dev *ud, int id);
+struct udma_rflow *xudma_rflow_get(struct udma_dev *ud, int id);
+
+void xudma_tchan_put(struct udma_dev *ud, struct udma_tchan *p);
+void xudma_rchan_put(struct udma_dev *ud, struct udma_rchan *p);
+void xudma_rflow_put(struct udma_dev *ud, struct udma_rflow *p);
+
+int xudma_tchan_get_id(struct udma_tchan *p);
+int xudma_rchan_get_id(struct udma_rchan *p);
+int xudma_rflow_get_id(struct udma_rflow *p);
+
+u32 xudma_tchanrt_read(struct udma_tchan *tchan, int reg);
+void xudma_tchanrt_write(struct udma_tchan *tchan, int reg, u32 val);
+u32 xudma_rchanrt_read(struct udma_rchan *rchan, int reg);
+void xudma_rchanrt_write(struct udma_rchan *rchan, int reg, u32 val);
+bool xudma_rflow_is_gp(struct udma_dev *ud, int id);
+
 #endif /* K3_UDMA_H_ */