1 /* 2 * Copyright (c) 2010 Broadcom Corporation 3 * 4 * Permission to use, copy, modify, and/or distribute this software for any 5 * purpose with or without fee is hereby granted, provided that the above 6 * copyright notice and this permission notice appear in all copies. 7 * 8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 11 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 13 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 14 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 15 */ 16 17 #ifndef _BRCM_DMA_H_ 18 #define _BRCM_DMA_H_ 19 20 #include <linux/delay.h> 21 #include <linux/skbuff.h> 22 #include "types.h" /* forward structure declarations */ 23 24 /* map/unmap direction */ 25 #define DMA_TX 1 /* TX direction for DMA */ 26 #define DMA_RX 2 /* RX direction for DMA */ 27 28 /* DMA structure: 29 * support two DMA engines: 32 bits address or 64 bit addressing 30 * basic DMA register set is per channel(transmit or receive) 31 * a pair of channels is defined for convenience 32 */ 33 34 /* 32 bits addressing */ 35 36 struct dma32diag { /* diag access */ 37 u32 fifoaddr; /* diag address */ 38 u32 fifodatalow; /* low 32bits of data */ 39 u32 fifodatahigh; /* high 32bits of data */ 40 u32 pad; /* reserved */ 41 }; 42 43 /* 64 bits addressing */ 44 45 /* dma registers per channel(xmt or rcv) */ 46 struct dma64regs { 47 u32 control; /* enable, et al */ 48 u32 ptr; /* last descriptor posted to chip */ 49 u32 addrlow; /* desc ring base address low 32-bits (8K aligned) */ 50 u32 addrhigh; /* desc ring base address bits 63:32 (8K aligned) */ 51 u32 status0; /* current descriptor, xmt state */ 52 u32 status1; /* active descriptor, xmt error */ 53 }; 54 55 /* range param for dma_getnexttxp() and dma_txreclaim */ 56 enum txd_range { 57 DMA_RANGE_ALL = 1, 58 DMA_RANGE_TRANSMITTED, 59 DMA_RANGE_TRANSFERED 60 }; 61 62 /* 63 * Exported data structure (read-only) 64 */ 65 /* export structure */ 66 struct dma_pub { 67 uint txavail; /* # free tx descriptors */ 68 uint dmactrlflags; /* dma control flags */ 69 70 /* rx error counters */ 71 uint rxgiants; /* rx giant frames */ 72 uint rxnobuf; /* rx out of dma descriptors */ 73 /* tx error counters */ 74 uint txnobuf; /* tx out of dma descriptors */ 75 }; 76 77 extern struct dma_pub *dma_attach(char *name, struct brcms_c_info *wlc, 78 uint txregbase, uint rxregbase, 79 uint ntxd, uint nrxd, 80 uint rxbufsize, int rxextheadroom, 81 uint nrxpost, uint rxoffset); 82 83 void dma_rxinit(struct dma_pub *pub); 84 int dma_rx(struct dma_pub *pub, struct sk_buff_head *skb_list); 85 bool dma_rxfill(struct dma_pub *pub); 86 bool dma_rxreset(struct dma_pub *pub); 87 bool dma_txreset(struct dma_pub *pub); 88 void dma_txinit(struct dma_pub *pub); 89 int dma_txfast(struct brcms_c_info *wlc, struct dma_pub *pub, 90 struct sk_buff *p0); 91 int dma_txpending(struct dma_pub *pub); 92 void dma_kick_tx(struct dma_pub *pub); 93 void dma_txsuspend(struct dma_pub *pub); 94 bool dma_txsuspended(struct dma_pub *pub); 95 void dma_txresume(struct dma_pub *pub); 96 void dma_txreclaim(struct dma_pub *pub, enum txd_range range); 97 void dma_rxreclaim(struct dma_pub *pub); 98 void dma_detach(struct dma_pub *pub); 99 unsigned long dma_getvar(struct dma_pub *pub, const char *name); 100 struct sk_buff *dma_getnexttxp(struct dma_pub *pub, enum txd_range range); 101 void dma_counterreset(struct dma_pub *pub); 102 103 void dma_walk_packets(struct dma_pub *dmah, void (*callback_fnc) 104 (void *pkt, void *arg_a), void *arg_a); 105 106 /* 107 * DMA(Bug) on bcm47xx chips seems to declare that the packet is ready, but 108 * the packet length is not updated yet (by DMA) on the expected time. 109 * Workaround is to hold processor till DMA updates the length, and stay off 110 * the bus to allow DMA update the length in buffer 111 */ 112 static inline void dma_spin_for_len(uint len, struct sk_buff *head) 113 { 114 #if defined(CONFIG_BCM47XX) 115 if (!len) { 116 while (!(len = *(u16 *) KSEG1ADDR(head->data))) 117 udelay(1); 118 119 *(u16 *) (head->data) = cpu_to_le16((u16) len); 120 } 121 #endif /* defined(CONFIG_BCM47XX) */ 122 } 123 124 #endif /* _BRCM_DMA_H_ */ 125