/*
* 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