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Diffstat (limited to 'drivers/thunderbolt/nhi.h')
| -rw-r--r-- | drivers/thunderbolt/nhi.h | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/drivers/thunderbolt/nhi.h b/drivers/thunderbolt/nhi.h new file mode 100644 index 000000000000..317242939b31 --- /dev/null +++ b/drivers/thunderbolt/nhi.h @@ -0,0 +1,114 @@ +/* + * Thunderbolt Cactus Ridge driver - NHI driver + * + * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com> + */ + +#ifndef DSL3510_H_ +#define DSL3510_H_ + +#include <linux/mutex.h> +#include <linux/workqueue.h> + +/** + * struct tb_nhi - thunderbolt native host interface + */ +struct tb_nhi { + struct mutex lock; /* + * Must be held during ring creation/destruction. + * Is acquired by interrupt_work when dispatching + * interrupts to individual rings. + **/ + struct pci_dev *pdev; + void __iomem *iobase; + struct tb_ring **tx_rings; + struct tb_ring **rx_rings; + struct work_struct interrupt_work; + u32 hop_count; /* Number of rings (end point hops) supported by NHI. */ +}; + +/** + * struct tb_ring - thunderbolt TX or RX ring associated with a NHI + */ +struct tb_ring { + struct mutex lock; /* must be acquired after nhi->lock */ + struct tb_nhi *nhi; + int size; + int hop; + int head; /* write next descriptor here */ + int tail; /* complete next descriptor here */ + struct ring_desc *descriptors; + dma_addr_t descriptors_dma; + struct list_head queue; + struct list_head in_flight; + struct work_struct work; + bool is_tx:1; /* rx otherwise */ + bool running:1; +}; + +struct ring_frame; +typedef void (*ring_cb)(struct tb_ring*, struct ring_frame*, bool canceled); + +/** + * struct ring_frame - for use with ring_rx/ring_tx + */ +struct ring_frame { + dma_addr_t buffer_phy; + ring_cb callback; + struct list_head list; + u32 size:12; /* TX: in, RX: out*/ + u32 flags:12; /* RX: out */ + u32 eof:4; /* TX:in, RX: out */ + u32 sof:4; /* TX:in, RX: out */ +}; + +#define TB_FRAME_SIZE 0x100 /* minimum size for ring_rx */ + +struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size); +struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size); +void ring_start(struct tb_ring *ring); +void ring_stop(struct tb_ring *ring); +void ring_free(struct tb_ring *ring); + +int __ring_enqueue(struct tb_ring *ring, struct ring_frame *frame); + +/** + * ring_rx() - enqueue a frame on an RX ring + * + * frame->buffer, frame->buffer_phy and frame->callback have to be set. The + * buffer must contain at least TB_FRAME_SIZE bytes. + * + * frame->callback will be invoked with frame->size, frame->flags, frame->eof, + * frame->sof set once the frame has been received. + * + * If ring_stop is called after the packet has been enqueued frame->callback + * will be called with canceled set to true. + * + * Return: Returns ESHUTDOWN if ring_stop has been called. Zero otherwise. + */ +static inline int ring_rx(struct tb_ring *ring, struct ring_frame *frame) +{ + WARN_ON(ring->is_tx); + return __ring_enqueue(ring, frame); +} + +/** + * ring_tx() - enqueue a frame on an TX ring + * + * frame->buffer, frame->buffer_phy, frame->callback, frame->size, frame->eof + * and frame->sof have to be set. + * + * frame->callback will be invoked with once the frame has been transmitted. + * + * If ring_stop is called after the packet has been enqueued frame->callback + * will be called with canceled set to true. + * + * Return: Returns ESHUTDOWN if ring_stop has been called. Zero otherwise. + */ +static inline int ring_tx(struct tb_ring *ring, struct ring_frame *frame) +{ + WARN_ON(!ring->is_tx); + return __ring_enqueue(ring, frame); +} + +#endif |