On 11/11/2019 11.00, Vinod Koul wrote:

On 11-11-19, 10:33, Peter Ujfalusi wrote:

quoted

On 11/11/2019 7.28, Vinod Koul wrote:

quoted

On 01-11-19, 10:41, Peter Ujfalusi wrote:

quoted

quoted

quoted

+	struct udma_static_tr static_tr;
+	char *name;
+
+	struct udma_tchan *tchan;
+	struct udma_rchan *rchan;
+	struct udma_rflow *rflow;
+
+	bool psil_paired;
+
+	int irq_num_ring;
+	int irq_num_udma;
+
+	bool cyclic;
+	bool paused;
+
+	enum udma_chan_state state;
+	struct completion teardown_completed;
+
+	u32 bcnt; /* number of bytes completed since the start of the channel */
+	u32 in_ring_cnt; /* number of descriptors in flight */
+
+	bool pkt_mode; /* TR or packet */
+	bool needs_epib; /* EPIB is needed for the communication or not */
+	u32 psd_size; /* size of Protocol Specific Data */
+	u32 metadata_size; /* (needs_epib ? 16:0) + psd_size */
+	u32 hdesc_size; /* Size of a packet descriptor in packet mode */
+	bool notdpkt; /* Suppress sending TDC packet */
+	int remote_thread_id;
+	u32 src_thread;
+	u32 dst_thread;
+	enum psil_endpoint_type ep_type;
+	bool enable_acc32;
+	bool enable_burst;
+	enum udma_tp_level channel_tpl; /* Channel Throughput Level */
+
+	/* dmapool for packet mode descriptors */
+	bool use_dma_pool;
+	struct dma_pool *hdesc_pool;
+
+	u32 id;
+	enum dma_transfer_direction dir;

why does channel have this, it already exists in descriptor

The channel can not change role, it is set when it was requested. In the

how do you do this on set? The channel is requested, we do not know the
direction. When prep_ is invoked we know it..

In UDMAP we must know it as a channel can do only one direction transfer:

dmas = <&main_udmap 0xc400>, <&main_udmap 0x4400>;
dma-names = "tx", "rx";

0xc400 is a destination thread ID, so the 'tx' channel can only do
MEM_TO_DEV
0x4400 is a source thread, 'rx' can only do DEV_TO_MEM.

We can not switch direction runtime.

- Péter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

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