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

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

quoted

+struct udma_chan {
+	struct virt_dma_chan vc;
+	struct dma_slave_config	cfg;
+	struct udma_dev *ud;
+	struct udma_desc *desc;
+	struct udma_desc *terminated_desc;

descriptor and not a list?

Yes, not a list. I have only one transfer (if any) submitted to
hardware. This is mostly due to the packet mode RX operation: no
prelinked support in UDMAP so I need to have as many descriptors queued
up as the number of sg elements.

I need to keep the terminated descriptor around to be able to free it up
_after_ UDMAP returned it to avoid it modifying released memory.

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
prep callbacks I do check if the direction matches with the channel's
direction.

quoted

+static irqreturn_t udma_udma_irq_handler(int irq, void *data)
+{
+	struct udma_chan *uc = data;
+
+	udma_tr_event_callback(uc);

any reason why we want to call a fn and not code here..?

No particular reason, I'll move them.

- Péter

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

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