20  * The PDC driver allows multiple messages to be pending in the descriptor
21  * rings. The tx_msg_start descriptor index indicates where the last message
22  * starts. The txin_numd value at this index indicates how many descriptor
55  * Minimum number of ring descriptor entries that must be free to tell mailbox
68 /* descriptor bumping macros */
141 /* descriptor flags */
142 #define D64_CTRL1_EOT   BIT(28)	/* end of descriptor table */
161 /* dma descriptor */
172 	u32  ptr;       /* last descriptor posted to chip */
173 	u32  addrlow;   /* descriptor ring base address low 32-bits */
174 	u32  addrhigh;  /* descriptor ring base address bits 63:32 */
175 	u32  status0;   /* last rx descriptor written by hw */
256  * context associated with a receive descriptor.
262  *             at a descriptor index. Not set for every index. For example,
263  *             if descriptor index i points to a scatterlist with 4 entries,
264  *             then the next three descriptor indexes don't have a value set.
313 	 * The base virtual address of DMA tx/rx descriptor rings. Corresponding
328 	struct dma64dd   *txd_64;  /* tx descriptor ring */
329 	struct dma64dd   *rxd_64;  /* rx descriptor ring */
331 	/* descriptor ring sizes */
338 	 * Index of next tx descriptor to reclaim. That is, the descriptor
345 	 * Index of the first receive descriptor for the sequence of
352 	/* Index of next tx descriptor to post. */
357 	 * at this tx descriptor index.
362 	 * Index of next rx descriptor to reclaim. This is the index of
363 	 * the next descriptor whose data has yet to be processed by the host.
368 	 * Index of the first receive descriptor for the sequence of
376 	 * Saved value of current hardware rx descriptor index.
382 	/* Index of next rx descriptor to post. */
400 	u32  txnobuf;          /* unable to create tx descriptor */
401 	u32  rxnobuf;          /* unable to create rx descriptor */
509  * pdc_build_rxd() - Build DMA descriptor to receive SPU result.
511  * @dma_addr:  DMA address of buffer that descriptor is being built for
513  * @flags:     Flags to be stored in descriptor
523 		"Writing rx descriptor for PDC %u at index %u with length %u. flags %#x\n",  in pdc_build_rxd()
536  * pdc_build_txd() - Build a DMA descriptor to transmit a SPU request to
541  * @flags:       Flags to be stored in descriptor
551 		"Writing tx descriptor for PDC %u at index %u with length %u, flags %#x\n",  in pdc_build_txd()
709 	 * Num descriptors needed. Conservatively assume we need a descriptor  in pdc_tx_list_sg_add()
714 	u32 bufcnt;	/* Number of bytes of buffer pointed to by descriptor */  in pdc_tx_list_sg_add()
715 	dma_addr_t databufptr;	/* DMA address to put in descriptor */  in pdc_tx_list_sg_add()
760 			/* Writing last descriptor for frame */  in pdc_tx_list_sg_add()
764 		/* Clear start of frame after first descriptor */  in pdc_tx_list_sg_add()
777  * Sets the index of the last descriptor written in both the rx and tx ring.
796  * pdc_rx_list_init() - Start a new receive descriptor list for a given PDC.
802  * Posts a single receive descriptor to hold the metadata that precedes a
804  * an 8-byte BCM header. Moves the msg_start descriptor indexes for both tx and
834 	 * of a new sequence of descriptor indexes that contain the fragments  in pdc_rx_list_init()
840 	/* This is always the first descriptor in the receive sequence */  in pdc_rx_list_init()
876 	 * Num descriptors needed. Conservatively assume we need a descriptor  in pdc_rx_list_sg_add()
881 	u32 bufcnt;	/* Number of bytes of buffer pointed to by descriptor */  in pdc_rx_list_sg_add()
882 	dma_addr_t databufptr;	/* DMA address to put in descriptor */  in pdc_rx_list_sg_add()
1019 	/* Set descriptor array base addresses */  in pdc_ring_init()
1051 		/* Every tx descriptor can be used for start of frame. */  in pdc_ring_init()
1056 			/* Last descriptor in ringset. Set End of Table. */  in pdc_ring_init()
1061 		/* Every rx descriptor can be used for start of frame */  in pdc_ring_init()
1066 			/* Last descriptor in ringset. Set End of Table. */  in pdc_ring_init()
1228 	 * and the entire sequence of descriptor to happen without another  in pdc_send_data()