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/*
* Thunderbolt Cactus Ridge driver - NHI driver
*
* Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
*/
#ifndef DSL3510_H_
#define DSL3510_H_
#include <linux/idr.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>
/**
* struct tb_nhi - thunderbolt native host interface
* @lock: Must be held during ring creation/destruction. Is acquired by
* interrupt_work when dispatching interrupts to individual rings.
* @pdev: Pointer to the PCI device
* @iobase: MMIO space of the NHI
* @tx_rings: All Tx rings available on this host controller
* @rx_rings: All Rx rings available on this host controller
* @msix_ida: Used to allocate MSI-X vectors for rings
* @interrupt_work: Work scheduled to handle ring interrupt when no
* MSI-X is used.
* @hop_count: Number of rings (end point hops) supported by NHI.
*/
struct tb_nhi {
struct mutex lock;
struct pci_dev *pdev;
void __iomem *iobase;
struct tb_ring **tx_rings;
struct tb_ring **rx_rings;
struct ida msix_ida;
struct work_struct interrupt_work;
u32 hop_count;
};
/**
* struct tb_ring - thunderbolt TX or RX ring associated with a NHI
* @lock: Lock serializing actions to this ring. Must be acquired after
* nhi->lock.
* @nhi: Pointer to the native host controller interface
* @size: Size of the ring
* @hop: Hop (DMA channel) associated with this ring
* @head: Head of the ring (write next descriptor here)
* @tail: Tail of the ring (complete next descriptor here)
* @descriptors: Allocated descriptors for this ring
* @queue: Queue holding frames to be transferred over this ring
* @in_flight: Queue holding frames that are currently in flight
* @work: Interrupt work structure
* @is_tx: Is the ring Tx or Rx
* @running: Is the ring running
* @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
* @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
* @flags: Ring specific flags
*/
struct tb_ring {
struct mutex lock;
struct tb_nhi *nhi;
int size;
int hop;
int head;
int tail;
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;
bool running:1;
int irq;
u8 vector;
unsigned int flags;
};
/* Leave ring interrupt enabled on suspend */
#define RING_FLAG_NO_SUSPEND BIT(0)
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,
unsigned int flags);
struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
unsigned int flags);
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
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