linux/drivers/net/wireless/broadcom/brcm80211/brcmsmac/dma.h

/*
 * Copyright (c) 2010 Broadcom Corporation
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef	_BRCM_DMA_H_
#define _BRCM_DMA_H_

#include <linux/delay.h>
#include <linux/skbuff.h>
#include "types.h"		/* forward structure declarations */

/* map/unmap direction */
#define DMA_TX …
#define DMA_RX …

/* DMA structure:
 *  support two DMA engines: 32 bits address or 64 bit addressing
 *  basic DMA register set is per channel(transmit or receive)
 *  a pair of channels is defined for convenience
 */

/* 32 bits addressing */

struct dma32diag { … };

/* 64 bits addressing */

/* dma registers per channel(xmt or rcv) */
struct dma64regs { … };

/* range param for dma_getnexttxp() and dma_txreclaim */
enum txd_range { … };

/*
 * Exported data structure (read-only)
 */
/* export structure */
struct dma_pub { … };

extern struct dma_pub *dma_attach(char *name, struct brcms_c_info *wlc,
				  uint txregbase, uint rxregbase,
				  uint ntxd, uint nrxd,
				  uint rxbufsize, int rxextheadroom,
				  uint nrxpost, uint rxoffset);

void dma_rxinit(struct dma_pub *pub);
int dma_rx(struct dma_pub *pub, struct sk_buff_head *skb_list);
bool dma_rxfill(struct dma_pub *pub);
bool dma_rxreset(struct dma_pub *pub);
bool dma_txreset(struct dma_pub *pub);
void dma_txinit(struct dma_pub *pub);
int dma_txfast(struct brcms_c_info *wlc, struct dma_pub *pub,
	       struct sk_buff *p0);
void dma_txflush(struct dma_pub *pub);
int dma_txpending(struct dma_pub *pub);
void dma_kick_tx(struct dma_pub *pub);
void dma_txsuspend(struct dma_pub *pub);
bool dma_txsuspended(struct dma_pub *pub);
void dma_txresume(struct dma_pub *pub);
void dma_txreclaim(struct dma_pub *pub, enum txd_range range);
void dma_rxreclaim(struct dma_pub *pub);
void dma_detach(struct dma_pub *pub);
unsigned long dma_getvar(struct dma_pub *pub, const char *name);
struct sk_buff *dma_getnexttxp(struct dma_pub *pub, enum txd_range range);
void dma_counterreset(struct dma_pub *pub);

void dma_walk_packets(struct dma_pub *dmah, void (*callback_fnc)
		      (void *pkt, void *arg_a), void *arg_a);

/*
 * DMA(Bug) on bcm47xx chips seems to declare that the packet is ready, but
 * the packet length is not updated yet (by DMA) on the expected time.
 * Workaround is to hold processor till DMA updates the length, and stay off
 * the bus to allow DMA update the length in buffer
 */
static inline void dma_spin_for_len(uint len, struct sk_buff *head)
{ … }

#endif				/* _BRCM_DMA_H_ */