drivers/net/wireless/b43/dma.h - maze/linux - Git at Google

 #ifndef B43_DMA_H_
 #define B43_DMA_H_

 #include <linux/err.h>

 #include "b43.h"


 /* DMA-Interrupt reasons. */
 #define B43_DMAIRQ_FATALMASK	((1 << 10) | (1 << 11) | (1 << 12) \
 					 | (1 << 14) | (1 << 15))
 #define B43_DMAIRQ_NONFATALMASK	(1 << 13)
 #define B43_DMAIRQ_RX_DONE		(1 << 16)

 /*** 32-bit DMA Engine. ***/

 /* 32-bit DMA controller registers. */
 #define B43_DMA32_TXCTL				0x00
 #define		B43_DMA32_TXENABLE			0x00000001
 #define		B43_DMA32_TXSUSPEND			0x00000002
 #define		B43_DMA32_TXLOOPBACK		0x00000004
 #define		B43_DMA32_TXFLUSH			0x00000010
 #define		B43_DMA32_TXADDREXT_MASK		0x00030000
 #define		B43_DMA32_TXADDREXT_SHIFT		16
 #define B43_DMA32_TXRING				0x04
 #define B43_DMA32_TXINDEX				0x08
 #define B43_DMA32_TXSTATUS				0x0C
 #define		B43_DMA32_TXDPTR			0x00000FFF
 #define		B43_DMA32_TXSTATE			0x0000F000
 #define			B43_DMA32_TXSTAT_DISABLED	0x00000000
 #define			B43_DMA32_TXSTAT_ACTIVE	0x00001000
 #define			B43_DMA32_TXSTAT_IDLEWAIT	0x00002000
 #define			B43_DMA32_TXSTAT_STOPPED	0x00003000
 #define			B43_DMA32_TXSTAT_SUSP	0x00004000
 #define		B43_DMA32_TXERROR			0x000F0000
 #define			B43_DMA32_TXERR_NOERR	0x00000000
 #define			B43_DMA32_TXERR_PROT	0x00010000
 #define			B43_DMA32_TXERR_UNDERRUN	0x00020000
 #define			B43_DMA32_TXERR_BUFREAD	0x00030000
 #define			B43_DMA32_TXERR_DESCREAD	0x00040000
 #define		B43_DMA32_TXACTIVE			0xFFF00000
 #define B43_DMA32_RXCTL				0x10
 #define		B43_DMA32_RXENABLE			0x00000001
 #define		B43_DMA32_RXFROFF_MASK		0x000000FE
 #define		B43_DMA32_RXFROFF_SHIFT		1
 #define		B43_DMA32_RXDIRECTFIFO		0x00000100
 #define		B43_DMA32_RXADDREXT_MASK		0x00030000
 #define		B43_DMA32_RXADDREXT_SHIFT		16
 #define B43_DMA32_RXRING				0x14
 #define B43_DMA32_RXINDEX				0x18
 #define B43_DMA32_RXSTATUS				0x1C
 #define		B43_DMA32_RXDPTR			0x00000FFF
 #define		B43_DMA32_RXSTATE			0x0000F000
 #define			B43_DMA32_RXSTAT_DISABLED	0x00000000
 #define			B43_DMA32_RXSTAT_ACTIVE	0x00001000
 #define			B43_DMA32_RXSTAT_IDLEWAIT	0x00002000
 #define			B43_DMA32_RXSTAT_STOPPED	0x00003000
 #define		B43_DMA32_RXERROR			0x000F0000
 #define			B43_DMA32_RXERR_NOERR	0x00000000
 #define			B43_DMA32_RXERR_PROT	0x00010000
 #define			B43_DMA32_RXERR_OVERFLOW	0x00020000
 #define			B43_DMA32_RXERR_BUFWRITE	0x00030000
 #define			B43_DMA32_RXERR_DESCREAD	0x00040000
 #define		B43_DMA32_RXACTIVE			0xFFF00000

 /* 32-bit DMA descriptor. */
 struct b43_dmadesc32 {
 	__le32 control;
 	__le32 address;
 } __attribute__ ((__packed__));
 #define B43_DMA32_DCTL_BYTECNT		0x00001FFF
 #define B43_DMA32_DCTL_ADDREXT_MASK		0x00030000
 #define B43_DMA32_DCTL_ADDREXT_SHIFT	16
 #define B43_DMA32_DCTL_DTABLEEND		0x10000000
 #define B43_DMA32_DCTL_IRQ			0x20000000
 #define B43_DMA32_DCTL_FRAMEEND		0x40000000
 #define B43_DMA32_DCTL_FRAMESTART		0x80000000

 /*** 64-bit DMA Engine. ***/

 /* 64-bit DMA controller registers. */
 #define B43_DMA64_TXCTL				0x00
 #define		B43_DMA64_TXENABLE			0x00000001
 #define		B43_DMA64_TXSUSPEND			0x00000002
 #define		B43_DMA64_TXLOOPBACK		0x00000004
 #define		B43_DMA64_TXFLUSH			0x00000010
 #define		B43_DMA64_TXADDREXT_MASK		0x00030000
 #define		B43_DMA64_TXADDREXT_SHIFT		16
 #define B43_DMA64_TXINDEX				0x04
 #define B43_DMA64_TXRINGLO				0x08
 #define B43_DMA64_TXRINGHI				0x0C
 #define B43_DMA64_TXSTATUS				0x10
 #define		B43_DMA64_TXSTATDPTR		0x00001FFF
 #define		B43_DMA64_TXSTAT			0xF0000000
 #define			B43_DMA64_TXSTAT_DISABLED	0x00000000
 #define			B43_DMA64_TXSTAT_ACTIVE	0x10000000
 #define			B43_DMA64_TXSTAT_IDLEWAIT	0x20000000
 #define			B43_DMA64_TXSTAT_STOPPED	0x30000000
 #define			B43_DMA64_TXSTAT_SUSP	0x40000000
 #define B43_DMA64_TXERROR				0x14
 #define		B43_DMA64_TXERRDPTR			0x0001FFFF
 #define		B43_DMA64_TXERR			0xF0000000
 #define			B43_DMA64_TXERR_NOERR	0x00000000
 #define			B43_DMA64_TXERR_PROT	0x10000000
 #define			B43_DMA64_TXERR_UNDERRUN	0x20000000
 #define			B43_DMA64_TXERR_TRANSFER	0x30000000
 #define			B43_DMA64_TXERR_DESCREAD	0x40000000
 #define			B43_DMA64_TXERR_CORE	0x50000000
 #define B43_DMA64_RXCTL				0x20
 #define		B43_DMA64_RXENABLE			0x00000001
 #define		B43_DMA64_RXFROFF_MASK		0x000000FE
 #define		B43_DMA64_RXFROFF_SHIFT		1
 #define		B43_DMA64_RXDIRECTFIFO		0x00000100
 #define		B43_DMA64_RXADDREXT_MASK		0x00030000
 #define		B43_DMA64_RXADDREXT_SHIFT		16
 #define B43_DMA64_RXINDEX				0x24
 #define B43_DMA64_RXRINGLO				0x28
 #define B43_DMA64_RXRINGHI				0x2C
 #define B43_DMA64_RXSTATUS				0x30
 #define		B43_DMA64_RXSTATDPTR		0x00001FFF
 #define		B43_DMA64_RXSTAT			0xF0000000
 #define			B43_DMA64_RXSTAT_DISABLED	0x00000000
 #define			B43_DMA64_RXSTAT_ACTIVE	0x10000000
 #define			B43_DMA64_RXSTAT_IDLEWAIT	0x20000000
 #define			B43_DMA64_RXSTAT_STOPPED	0x30000000
 #define			B43_DMA64_RXSTAT_SUSP	0x40000000
 #define B43_DMA64_RXERROR				0x34
 #define		B43_DMA64_RXERRDPTR			0x0001FFFF
 #define		B43_DMA64_RXERR			0xF0000000
 #define			B43_DMA64_RXERR_NOERR	0x00000000
 #define			B43_DMA64_RXERR_PROT	0x10000000
 #define			B43_DMA64_RXERR_UNDERRUN	0x20000000
 #define			B43_DMA64_RXERR_TRANSFER	0x30000000
 #define			B43_DMA64_RXERR_DESCREAD	0x40000000
 #define			B43_DMA64_RXERR_CORE	0x50000000

 /* 64-bit DMA descriptor. */
 struct b43_dmadesc64 {
 	__le32 control0;
 	__le32 control1;
 	__le32 address_low;
 	__le32 address_high;
 } __attribute__ ((__packed__));
 #define B43_DMA64_DCTL0_DTABLEEND		0x10000000
 #define B43_DMA64_DCTL0_IRQ			0x20000000
 #define B43_DMA64_DCTL0_FRAMEEND		0x40000000
 #define B43_DMA64_DCTL0_FRAMESTART		0x80000000
 #define B43_DMA64_DCTL1_BYTECNT		0x00001FFF
 #define B43_DMA64_DCTL1_ADDREXT_MASK	0x00030000
 #define B43_DMA64_DCTL1_ADDREXT_SHIFT	16

 struct b43_dmadesc_generic {
 	union {
 		struct b43_dmadesc32 dma32;
 		struct b43_dmadesc64 dma64;
 	} __attribute__ ((__packed__));
 } __attribute__ ((__packed__));

 /* Misc DMA constants */
 #define B43_DMA_RINGMEMSIZE		PAGE_SIZE
 #define B43_DMA0_RX_FRAMEOFFSET		30

 /* DMA engine tuning knobs */
 #define B43_TXRING_SLOTS		256
 #define B43_RXRING_SLOTS		64
 #define B43_DMA0_RX_BUFFERSIZE		IEEE80211_MAX_FRAME_LEN

 /* Pointer poison */
 #define B43_DMA_PTR_POISON		((void *)ERR_PTR(-ENOMEM))
 #define b43_dma_ptr_is_poisoned(ptr)	(unlikely((ptr) == B43_DMA_PTR_POISON))


 struct sk_buff;
 struct b43_private;
 struct b43_txstatus;

 struct b43_dmadesc_meta {
 	/* The kernel DMA-able buffer. */
 	struct sk_buff *skb;
 	/* DMA base bus-address of the descriptor buffer. */
 	dma_addr_t dmaaddr;
 	/* ieee80211 TX status. Only used once per 802.11 frag. */
 	bool is_last_fragment;
 };

 struct b43_dmaring;

 /* Lowlevel DMA operations that differ between 32bit and 64bit DMA. */
 struct b43_dma_ops {
 	struct b43_dmadesc_generic *(*idx2desc) (struct b43_dmaring * ring,
 						 int slot,
 						 struct b43_dmadesc_meta **
 						 meta);
 	void (*fill_descriptor) (struct b43_dmaring * ring,
 				 struct b43_dmadesc_generic * desc,
 				 dma_addr_t dmaaddr, u16 bufsize, int start,
 				 int end, int irq);
 	void (*poke_tx) (struct b43_dmaring * ring, int slot);
 	void (*tx_suspend) (struct b43_dmaring * ring);
 	void (*tx_resume) (struct b43_dmaring * ring);
 	int (*get_current_rxslot) (struct b43_dmaring * ring);
 	void (*set_current_rxslot) (struct b43_dmaring * ring, int slot);
 };

 enum b43_dmatype {
 	B43_DMA_30BIT	= 30,
 	B43_DMA_32BIT	= 32,
 	B43_DMA_64BIT	= 64,
 };

 struct b43_dmaring {
 	/* Lowlevel DMA ops. */
 	const struct b43_dma_ops *ops;
 	/* Kernel virtual base address of the ring memory. */
 	void *descbase;
 	/* Meta data about all descriptors. */
 	struct b43_dmadesc_meta *meta;
 	/* Cache of TX headers for each TX frame.
 	 * This is to avoid an allocation on each TX.
 	 * This is NULL for an RX ring.
 	 */
 	u8 *txhdr_cache;
 	/* (Unadjusted) DMA base bus-address of the ring memory. */
 	dma_addr_t dmabase;
 	/* Number of descriptor slots in the ring. */
 	int nr_slots;
 	/* Number of used descriptor slots. */
 	int used_slots;
 	/* Currently used slot in the ring. */
 	int current_slot;
 	/* Frameoffset in octets. */
 	u32 frameoffset;
 	/* Descriptor buffer size. */
 	u16 rx_buffersize;
 	/* The MMIO base register of the DMA controller. */
 	u16 mmio_base;
 	/* DMA controller index number (0-5). */
 	int index;
 	/* Boolean. Is this a TX ring? */
 	bool tx;
 	/* The type of DMA engine used. */
 	enum b43_dmatype type;
 	/* Boolean. Is this ring stopped at ieee80211 level? */
 	bool stopped;
 	/* The QOS priority assigned to this ring. Only used for TX rings.
 	 * This is the mac80211 "queue" value. */
 	u8 queue_prio;
 	struct b43_wldev *dev;
 #ifdef CONFIG_B43_DEBUG
 	/* Maximum number of used slots. */
 	int max_used_slots;
 	/* Last time we injected a ring overflow. */
 	unsigned long last_injected_overflow;
 	/* Statistics: Number of successfully transmitted packets */
 	u64 nr_succeed_tx_packets;
 	/* Statistics: Number of failed TX packets */
 	u64 nr_failed_tx_packets;
 	/* Statistics: Total number of TX plus all retries. */
 	u64 nr_total_packet_tries;
 #endif /* CONFIG_B43_DEBUG */
 };

 static inline u32 b43_dma_read(struct b43_dmaring *ring, u16 offset)
 {
 	return b43_read32(ring->dev, ring->mmio_base + offset);
 }

 static inline void b43_dma_write(struct b43_dmaring *ring, u16 offset, u32 value)
 {
 	b43_write32(ring->dev, ring->mmio_base + offset, value);
 }

 int b43_dma_init(struct b43_wldev *dev);
 void b43_dma_free(struct b43_wldev *dev);

 void b43_dma_tx_suspend(struct b43_wldev *dev);
 void b43_dma_tx_resume(struct b43_wldev *dev);

 int b43_dma_tx(struct b43_wldev *dev,
 	       struct sk_buff *skb);
 void b43_dma_handle_txstatus(struct b43_wldev *dev,
 			     const struct b43_txstatus *status);

 void b43_dma_rx(struct b43_dmaring *ring);

 void b43_dma_direct_fifo_rx(struct b43_wldev *dev,
 			    unsigned int engine_index, bool enable);

 #endif /* B43_DMA_H_ */
	#ifndef B43_DMA_H_
	#define B43_DMA_H_

	#include <linux/err.h>

	#include "b43.h"


	/* DMA-Interrupt reasons. */
	#define B43_DMAIRQ_FATALMASK ((1 << 10) \| (1 << 11) \| (1 << 12) \
	\| (1 << 14) \| (1 << 15))
	#define B43_DMAIRQ_NONFATALMASK (1 << 13)
	#define B43_DMAIRQ_RX_DONE (1 << 16)

	/* 32-bit DMA Engine. */

	/* 32-bit DMA controller registers. */
	#define B43_DMA32_TXCTL 0x00
	#define B43_DMA32_TXENABLE 0x00000001
	#define B43_DMA32_TXSUSPEND 0x00000002
	#define B43_DMA32_TXLOOPBACK 0x00000004
	#define B43_DMA32_TXFLUSH 0x00000010
	#define B43_DMA32_TXADDREXT_MASK 0x00030000
	#define B43_DMA32_TXADDREXT_SHIFT 16
	#define B43_DMA32_TXRING 0x04
	#define B43_DMA32_TXINDEX 0x08
	#define B43_DMA32_TXSTATUS 0x0C
	#define B43_DMA32_TXDPTR 0x00000FFF
	#define B43_DMA32_TXSTATE 0x0000F000
	#define B43_DMA32_TXSTAT_DISABLED 0x00000000
	#define B43_DMA32_TXSTAT_ACTIVE 0x00001000
	#define B43_DMA32_TXSTAT_IDLEWAIT 0x00002000
	#define B43_DMA32_TXSTAT_STOPPED 0x00003000
	#define B43_DMA32_TXSTAT_SUSP 0x00004000
	#define B43_DMA32_TXERROR 0x000F0000
	#define B43_DMA32_TXERR_NOERR 0x00000000
	#define B43_DMA32_TXERR_PROT 0x00010000
	#define B43_DMA32_TXERR_UNDERRUN 0x00020000
	#define B43_DMA32_TXERR_BUFREAD 0x00030000
	#define B43_DMA32_TXERR_DESCREAD 0x00040000
	#define B43_DMA32_TXACTIVE 0xFFF00000
	#define B43_DMA32_RXCTL 0x10
	#define B43_DMA32_RXENABLE 0x00000001
	#define B43_DMA32_RXFROFF_MASK 0x000000FE
	#define B43_DMA32_RXFROFF_SHIFT 1
	#define B43_DMA32_RXDIRECTFIFO 0x00000100
	#define B43_DMA32_RXADDREXT_MASK 0x00030000
	#define B43_DMA32_RXADDREXT_SHIFT 16
	#define B43_DMA32_RXRING 0x14
	#define B43_DMA32_RXINDEX 0x18
	#define B43_DMA32_RXSTATUS 0x1C
	#define B43_DMA32_RXDPTR 0x00000FFF
	#define B43_DMA32_RXSTATE 0x0000F000
	#define B43_DMA32_RXSTAT_DISABLED 0x00000000
	#define B43_DMA32_RXSTAT_ACTIVE 0x00001000
	#define B43_DMA32_RXSTAT_IDLEWAIT 0x00002000
	#define B43_DMA32_RXSTAT_STOPPED 0x00003000
	#define B43_DMA32_RXERROR 0x000F0000
	#define B43_DMA32_RXERR_NOERR 0x00000000
	#define B43_DMA32_RXERR_PROT 0x00010000
	#define B43_DMA32_RXERR_OVERFLOW 0x00020000
	#define B43_DMA32_RXERR_BUFWRITE 0x00030000
	#define B43_DMA32_RXERR_DESCREAD 0x00040000
	#define B43_DMA32_RXACTIVE 0xFFF00000

	/* 32-bit DMA descriptor. */
	struct b43_dmadesc32 {
	__le32 control;
	__le32 address;
	} __attribute__ ((__packed__));
	#define B43_DMA32_DCTL_BYTECNT 0x00001FFF
	#define B43_DMA32_DCTL_ADDREXT_MASK 0x00030000
	#define B43_DMA32_DCTL_ADDREXT_SHIFT 16
	#define B43_DMA32_DCTL_DTABLEEND 0x10000000
	#define B43_DMA32_DCTL_IRQ 0x20000000
	#define B43_DMA32_DCTL_FRAMEEND 0x40000000
	#define B43_DMA32_DCTL_FRAMESTART 0x80000000

	/* 64-bit DMA Engine. */

	/* 64-bit DMA controller registers. */
	#define B43_DMA64_TXCTL 0x00
	#define B43_DMA64_TXENABLE 0x00000001
	#define B43_DMA64_TXSUSPEND 0x00000002
	#define B43_DMA64_TXLOOPBACK 0x00000004
	#define B43_DMA64_TXFLUSH 0x00000010
	#define B43_DMA64_TXADDREXT_MASK 0x00030000
	#define B43_DMA64_TXADDREXT_SHIFT 16
	#define B43_DMA64_TXINDEX 0x04
	#define B43_DMA64_TXRINGLO 0x08
	#define B43_DMA64_TXRINGHI 0x0C
	#define B43_DMA64_TXSTATUS 0x10
	#define B43_DMA64_TXSTATDPTR 0x00001FFF
	#define B43_DMA64_TXSTAT 0xF0000000
	#define B43_DMA64_TXSTAT_DISABLED 0x00000000
	#define B43_DMA64_TXSTAT_ACTIVE 0x10000000
	#define B43_DMA64_TXSTAT_IDLEWAIT 0x20000000
	#define B43_DMA64_TXSTAT_STOPPED 0x30000000
	#define B43_DMA64_TXSTAT_SUSP 0x40000000
	#define B43_DMA64_TXERROR 0x14
	#define B43_DMA64_TXERRDPTR 0x0001FFFF
	#define B43_DMA64_TXERR 0xF0000000
	#define B43_DMA64_TXERR_NOERR 0x00000000
	#define B43_DMA64_TXERR_PROT 0x10000000
	#define B43_DMA64_TXERR_UNDERRUN 0x20000000
	#define B43_DMA64_TXERR_TRANSFER 0x30000000
	#define B43_DMA64_TXERR_DESCREAD 0x40000000
	#define B43_DMA64_TXERR_CORE 0x50000000
	#define B43_DMA64_RXCTL 0x20
	#define B43_DMA64_RXENABLE 0x00000001
	#define B43_DMA64_RXFROFF_MASK 0x000000FE
	#define B43_DMA64_RXFROFF_SHIFT 1
	#define B43_DMA64_RXDIRECTFIFO 0x00000100
	#define B43_DMA64_RXADDREXT_MASK 0x00030000
	#define B43_DMA64_RXADDREXT_SHIFT 16
	#define B43_DMA64_RXINDEX 0x24
	#define B43_DMA64_RXRINGLO 0x28
	#define B43_DMA64_RXRINGHI 0x2C
	#define B43_DMA64_RXSTATUS 0x30
	#define B43_DMA64_RXSTATDPTR 0x00001FFF
	#define B43_DMA64_RXSTAT 0xF0000000
	#define B43_DMA64_RXSTAT_DISABLED 0x00000000
	#define B43_DMA64_RXSTAT_ACTIVE 0x10000000
	#define B43_DMA64_RXSTAT_IDLEWAIT 0x20000000
	#define B43_DMA64_RXSTAT_STOPPED 0x30000000
	#define B43_DMA64_RXSTAT_SUSP 0x40000000
	#define B43_DMA64_RXERROR 0x34
	#define B43_DMA64_RXERRDPTR 0x0001FFFF
	#define B43_DMA64_RXERR 0xF0000000
	#define B43_DMA64_RXERR_NOERR 0x00000000
	#define B43_DMA64_RXERR_PROT 0x10000000
	#define B43_DMA64_RXERR_UNDERRUN 0x20000000
	#define B43_DMA64_RXERR_TRANSFER 0x30000000
	#define B43_DMA64_RXERR_DESCREAD 0x40000000
	#define B43_DMA64_RXERR_CORE 0x50000000

	/* 64-bit DMA descriptor. */
	struct b43_dmadesc64 {
	__le32 control0;
	__le32 control1;
	__le32 address_low;
	__le32 address_high;
	} __attribute__ ((__packed__));
	#define B43_DMA64_DCTL0_DTABLEEND 0x10000000
	#define B43_DMA64_DCTL0_IRQ 0x20000000
	#define B43_DMA64_DCTL0_FRAMEEND 0x40000000
	#define B43_DMA64_DCTL0_FRAMESTART 0x80000000
	#define B43_DMA64_DCTL1_BYTECNT 0x00001FFF
	#define B43_DMA64_DCTL1_ADDREXT_MASK 0x00030000
	#define B43_DMA64_DCTL1_ADDREXT_SHIFT 16

	struct b43_dmadesc_generic {
	union {
	struct b43_dmadesc32 dma32;
	struct b43_dmadesc64 dma64;
	} __attribute__ ((__packed__));
	} __attribute__ ((__packed__));

	/* Misc DMA constants */
	#define B43_DMA_RINGMEMSIZE PAGE_SIZE
	#define B43_DMA0_RX_FRAMEOFFSET 30

	/* DMA engine tuning knobs */
	#define B43_TXRING_SLOTS 256
	#define B43_RXRING_SLOTS 64
	#define B43_DMA0_RX_BUFFERSIZE IEEE80211_MAX_FRAME_LEN

	/* Pointer poison */
	#define B43_DMA_PTR_POISON ((void *)ERR_PTR(-ENOMEM))
	#define b43_dma_ptr_is_poisoned(ptr) (unlikely((ptr) == B43_DMA_PTR_POISON))


	struct sk_buff;
	struct b43_private;
	struct b43_txstatus;

	struct b43_dmadesc_meta {
	/* The kernel DMA-able buffer. */
	struct sk_buff *skb;
	/* DMA base bus-address of the descriptor buffer. */
	dma_addr_t dmaaddr;
	/* ieee80211 TX status. Only used once per 802.11 frag. */
	bool is_last_fragment;
	};

	struct b43_dmaring;

	/* Lowlevel DMA operations that differ between 32bit and 64bit DMA. */
	struct b43_dma_ops {
	struct b43_dmadesc_generic (idx2desc) (struct b43_dmaring * ring,
	int slot,
	struct b43_dmadesc_meta **
	meta);
	void (fill_descriptor) (struct b43_dmaring ring,
	struct b43_dmadesc_generic * desc,
	dma_addr_t dmaaddr, u16 bufsize, int start,
	int end, int irq);
	void (poke_tx) (struct b43_dmaring ring, int slot);
	void (tx_suspend) (struct b43_dmaring ring);
	void (tx_resume) (struct b43_dmaring ring);
	int (get_current_rxslot) (struct b43_dmaring ring);
	void (set_current_rxslot) (struct b43_dmaring ring, int slot);
	};

	enum b43_dmatype {
	B43_DMA_30BIT = 30,
	B43_DMA_32BIT = 32,
	B43_DMA_64BIT = 64,
	};

	struct b43_dmaring {
	/* Lowlevel DMA ops. */
	const struct b43_dma_ops *ops;
	/* Kernel virtual base address of the ring memory. */
	void *descbase;
	/* Meta data about all descriptors. */
	struct b43_dmadesc_meta *meta;
	/* Cache of TX headers for each TX frame.
	* This is to avoid an allocation on each TX.
	* This is NULL for an RX ring.
	*/
	u8 *txhdr_cache;
	/* (Unadjusted) DMA base bus-address of the ring memory. */
	dma_addr_t dmabase;
	/* Number of descriptor slots in the ring. */
	int nr_slots;
	/* Number of used descriptor slots. */
	int used_slots;
	/* Currently used slot in the ring. */
	int current_slot;
	/* Frameoffset in octets. */
	u32 frameoffset;
	/* Descriptor buffer size. */
	u16 rx_buffersize;
	/* The MMIO base register of the DMA controller. */
	u16 mmio_base;
	/* DMA controller index number (0-5). */
	int index;
	/* Boolean. Is this a TX ring? */
	bool tx;
	/* The type of DMA engine used. */
	enum b43_dmatype type;
	/* Boolean. Is this ring stopped at ieee80211 level? */
	bool stopped;
	/* The QOS priority assigned to this ring. Only used for TX rings.
	* This is the mac80211 "queue" value. */
	u8 queue_prio;
	struct b43_wldev *dev;
	#ifdef CONFIG_B43_DEBUG
	/* Maximum number of used slots. */
	int max_used_slots;
	/* Last time we injected a ring overflow. */
	unsigned long last_injected_overflow;
	/* Statistics: Number of successfully transmitted packets */
	u64 nr_succeed_tx_packets;
	/* Statistics: Number of failed TX packets */
	u64 nr_failed_tx_packets;
	/* Statistics: Total number of TX plus all retries. */
	u64 nr_total_packet_tries;
	#endif /* CONFIG_B43_DEBUG */
	};

	static inline u32 b43_dma_read(struct b43_dmaring *ring, u16 offset)
	{
	return b43_read32(ring->dev, ring->mmio_base + offset);
	}

	static inline void b43_dma_write(struct b43_dmaring *ring, u16 offset, u32 value)
	{
	b43_write32(ring->dev, ring->mmio_base + offset, value);
	}

	int b43_dma_init(struct b43_wldev *dev);
	void b43_dma_free(struct b43_wldev *dev);

	void b43_dma_tx_suspend(struct b43_wldev *dev);
	void b43_dma_tx_resume(struct b43_wldev *dev);

	int b43_dma_tx(struct b43_wldev *dev,
	struct sk_buff *skb);
	void b43_dma_handle_txstatus(struct b43_wldev *dev,
	const struct b43_txstatus *status);

	void b43_dma_rx(struct b43_dmaring *ring);

	void b43_dma_direct_fifo_rx(struct b43_wldev *dev,
	unsigned int engine_index, bool enable);

	#endif /* B43_DMA_H_ */