cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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tehuti.h (15145B)


      1/* SPDX-License-Identifier: GPL-2.0-or-later */
      2/*
      3 * Tehuti Networks(R) Network Driver
      4 * Copyright (C) 2007 Tehuti Networks Ltd. All rights reserved
      5 */
      6
      7#ifndef _TEHUTI_H
      8#define _TEHUTI_H
      9
     10#include <linux/module.h>
     11#include <linux/kernel.h>
     12#include <linux/netdevice.h>
     13#include <linux/etherdevice.h>
     14#include <linux/pci.h>
     15#include <linux/delay.h>
     16#include <linux/ethtool.h>
     17#include <linux/mii.h>
     18#include <linux/crc32.h>
     19#include <linux/uaccess.h>
     20#include <linux/in.h>
     21#include <linux/ip.h>
     22#include <linux/tcp.h>
     23#include <linux/sched.h>
     24#include <linux/tty.h>
     25#include <linux/if_vlan.h>
     26#include <linux/interrupt.h>
     27#include <linux/vmalloc.h>
     28#include <linux/firmware.h>
     29#include <asm/byteorder.h>
     30#include <linux/dma-mapping.h>
     31#include <linux/slab.h>
     32
     33/* Compile Time Switches */
     34/* start */
     35#define BDX_TSO
     36#define BDX_LLTX
     37#define BDX_DELAY_WPTR
     38/* #define BDX_MSI */
     39/* end */
     40
     41#if !defined CONFIG_PCI_MSI
     42#   undef BDX_MSI
     43#endif
     44
     45#define BDX_DEF_MSG_ENABLE	(NETIF_MSG_DRV          | \
     46				NETIF_MSG_PROBE        | \
     47				NETIF_MSG_LINK)
     48
     49/* ioctl ops */
     50#define BDX_OP_READ  1
     51#define BDX_OP_WRITE 2
     52
     53/* RX copy break size */
     54#define BDX_COPYBREAK    257
     55
     56#define DRIVER_AUTHOR     "Tehuti Networks(R)"
     57#define BDX_DRV_DESC      "Tehuti Networks(R) Network Driver"
     58#define BDX_DRV_NAME      "tehuti"
     59#define BDX_NIC_NAME      "Tehuti 10 Giga TOE SmartNIC"
     60#define BDX_NIC2PORT_NAME "Tehuti 2-Port 10 Giga TOE SmartNIC"
     61#define BDX_DRV_VERSION   "7.29.3"
     62
     63#ifdef BDX_MSI
     64#    define BDX_MSI_STRING "msi "
     65#else
     66#    define BDX_MSI_STRING ""
     67#endif
     68
     69/* netdev tx queue len for Luxor. default value is, btw, 1000
     70 * ifcontig eth1 txqueuelen 3000 - to change it at runtime */
     71#define BDX_NDEV_TXQ_LEN 3000
     72
     73/* Max MTU for Jumbo Frame mode, per tehutinetworks.net Features FAQ is 16k */
     74#define BDX_MAX_MTU	(16 * 1024)
     75
     76#define FIFO_SIZE  4096
     77#define FIFO_EXTRA_SPACE            1024
     78
     79#if BITS_PER_LONG == 64
     80#    define H32_64(x)  (u32) ((u64)(x) >> 32)
     81#    define L32_64(x)  (u32) ((u64)(x) & 0xffffffff)
     82#elif BITS_PER_LONG == 32
     83#    define H32_64(x)  0
     84#    define L32_64(x)  ((u32) (x))
     85#else				/* BITS_PER_LONG == ?? */
     86#    error BITS_PER_LONG is undefined. Must be 64 or 32
     87#endif				/* BITS_PER_LONG */
     88
     89#ifdef __BIG_ENDIAN
     90#   define CPU_CHIP_SWAP32(x) swab32(x)
     91#   define CPU_CHIP_SWAP16(x) swab16(x)
     92#else
     93#   define CPU_CHIP_SWAP32(x) (x)
     94#   define CPU_CHIP_SWAP16(x) (x)
     95#endif
     96
     97#define READ_REG(pp, reg)         readl(pp->pBdxRegs + reg)
     98#define WRITE_REG(pp, reg, val)   writel(val, pp->pBdxRegs + reg)
     99
    100#ifndef NET_IP_ALIGN
    101#   define NET_IP_ALIGN 2
    102#endif
    103
    104#ifndef NETDEV_TX_OK
    105#   define NETDEV_TX_OK 0
    106#endif
    107
    108#define LUXOR_MAX_PORT     2
    109#define BDX_MAX_RX_DONE    150
    110#define BDX_TXF_DESC_SZ    16
    111#define BDX_MAX_TX_LEVEL   (priv->txd_fifo0.m.memsz - 16)
    112#define BDX_MIN_TX_LEVEL   256
    113#define BDX_NO_UPD_PACKETS 40
    114
    115struct pci_nic {
    116	int port_num;
    117	void __iomem *regs;
    118	int irq_type;
    119	struct bdx_priv *priv[LUXOR_MAX_PORT];
    120};
    121
    122enum { IRQ_INTX, IRQ_MSI, IRQ_MSIX };
    123
    124#define PCK_TH_MULT   128
    125#define INT_COAL_MULT 2
    126
    127#define BITS_MASK(nbits)			((1<<nbits)-1)
    128#define GET_BITS_SHIFT(x, nbits, nshift)	(((x)>>nshift)&BITS_MASK(nbits))
    129#define BITS_SHIFT_MASK(nbits, nshift)		(BITS_MASK(nbits)<<nshift)
    130#define BITS_SHIFT_VAL(x, nbits, nshift)	(((x)&BITS_MASK(nbits))<<nshift)
    131#define BITS_SHIFT_CLEAR(x, nbits, nshift)	\
    132	((x)&(~BITS_SHIFT_MASK(nbits, nshift)))
    133
    134#define GET_INT_COAL(x)				GET_BITS_SHIFT(x, 15, 0)
    135#define GET_INT_COAL_RC(x)			GET_BITS_SHIFT(x, 1, 15)
    136#define GET_RXF_TH(x)				GET_BITS_SHIFT(x, 4, 16)
    137#define GET_PCK_TH(x)				GET_BITS_SHIFT(x, 4, 20)
    138
    139#define INT_REG_VAL(coal, coal_rc, rxf_th, pck_th)	\
    140	((coal)|((coal_rc)<<15)|((rxf_th)<<16)|((pck_th)<<20))
    141
    142struct fifo {
    143	dma_addr_t da;		/* physical address of fifo (used by HW) */
    144	char *va;		/* virtual address of fifo (used by SW) */
    145	u32 rptr, wptr;		/* cached values of RPTR and WPTR registers,
    146				   they're 32 bits on both 32 and 64 archs */
    147	u16 reg_CFG0, reg_CFG1;
    148	u16 reg_RPTR, reg_WPTR;
    149	u16 memsz;		/* memory size allocated for fifo */
    150	u16 size_mask;
    151	u16 pktsz;		/* skb packet size to allocate */
    152	u16 rcvno;		/* number of buffers that come from this RXF */
    153};
    154
    155struct txf_fifo {
    156	struct fifo m;		/* minimal set of variables used by all fifos */
    157};
    158
    159struct txd_fifo {
    160	struct fifo m;		/* minimal set of variables used by all fifos */
    161};
    162
    163struct rxf_fifo {
    164	struct fifo m;		/* minimal set of variables used by all fifos */
    165};
    166
    167struct rxd_fifo {
    168	struct fifo m;		/* minimal set of variables used by all fifos */
    169};
    170
    171struct rx_map {
    172	u64 dma;
    173	struct sk_buff *skb;
    174};
    175
    176struct rxdb {
    177	int *stack;
    178	struct rx_map *elems;
    179	int nelem;
    180	int top;
    181};
    182
    183union bdx_dma_addr {
    184	dma_addr_t dma;
    185	struct sk_buff *skb;
    186};
    187
    188/* Entry in the db.
    189 * if len == 0 addr is dma
    190 * if len != 0 addr is skb */
    191struct tx_map {
    192	union bdx_dma_addr addr;
    193	int len;
    194};
    195
    196/* tx database - implemented as circular fifo buffer*/
    197struct txdb {
    198	struct tx_map *start;	/* points to the first element */
    199	struct tx_map *end;	/* points just AFTER the last element */
    200	struct tx_map *rptr;	/* points to the next element to read */
    201	struct tx_map *wptr;	/* points to the next element to write */
    202	int size;		/* number of elements in the db */
    203};
    204
    205/*Internal stats structure*/
    206struct bdx_stats {
    207	u64 InUCast;			/* 0x7200 */
    208	u64 InMCast;			/* 0x7210 */
    209	u64 InBCast;			/* 0x7220 */
    210	u64 InPkts;			/* 0x7230 */
    211	u64 InErrors;			/* 0x7240 */
    212	u64 InDropped;			/* 0x7250 */
    213	u64 FrameTooLong;		/* 0x7260 */
    214	u64 FrameSequenceErrors;	/* 0x7270 */
    215	u64 InVLAN;			/* 0x7280 */
    216	u64 InDroppedDFE;		/* 0x7290 */
    217	u64 InDroppedIntFull;		/* 0x72A0 */
    218	u64 InFrameAlignErrors;		/* 0x72B0 */
    219
    220	/* 0x72C0-0x72E0 RSRV */
    221
    222	u64 OutUCast;			/* 0x72F0 */
    223	u64 OutMCast;			/* 0x7300 */
    224	u64 OutBCast;			/* 0x7310 */
    225	u64 OutPkts;			/* 0x7320 */
    226
    227	/* 0x7330-0x7360 RSRV */
    228
    229	u64 OutVLAN;			/* 0x7370 */
    230	u64 InUCastOctects;		/* 0x7380 */
    231	u64 OutUCastOctects;		/* 0x7390 */
    232
    233	/* 0x73A0-0x73B0 RSRV */
    234
    235	u64 InBCastOctects;		/* 0x73C0 */
    236	u64 OutBCastOctects;		/* 0x73D0 */
    237	u64 InOctects;			/* 0x73E0 */
    238	u64 OutOctects;			/* 0x73F0 */
    239};
    240
    241struct bdx_priv {
    242	void __iomem *pBdxRegs;
    243	struct net_device *ndev;
    244
    245	struct napi_struct napi;
    246
    247	/* RX FIFOs: 1 for data (full) descs, and 2 for free descs */
    248	struct rxd_fifo rxd_fifo0;
    249	struct rxf_fifo rxf_fifo0;
    250	struct rxdb *rxdb;	/* rx dbs to store skb pointers */
    251	int napi_stop;
    252
    253	/* Tx FIFOs: 1 for data desc, 1 for empty (acks) desc */
    254	struct txd_fifo txd_fifo0;
    255	struct txf_fifo txf_fifo0;
    256
    257	struct txdb txdb;
    258	int tx_level;
    259#ifdef BDX_DELAY_WPTR
    260	int tx_update_mark;
    261	int tx_noupd;
    262#endif
    263	spinlock_t tx_lock;	/* NETIF_F_LLTX mode */
    264
    265	/* rarely used */
    266	u8 port;
    267	u32 msg_enable;
    268	int stats_flag;
    269	struct bdx_stats hw_stats;
    270	struct pci_dev *pdev;
    271
    272	struct pci_nic *nic;
    273
    274	u8 txd_size;
    275	u8 txf_size;
    276	u8 rxd_size;
    277	u8 rxf_size;
    278	u32 rdintcm;
    279	u32 tdintcm;
    280};
    281
    282/* RX FREE descriptor - 64bit*/
    283struct rxf_desc {
    284	u32 info;		/* Buffer Count + Info - described below */
    285	u32 va_lo;		/* VAdr[31:0] */
    286	u32 va_hi;		/* VAdr[63:32] */
    287	u32 pa_lo;		/* PAdr[31:0] */
    288	u32 pa_hi;		/* PAdr[63:32] */
    289	u32 len;		/* Buffer Length */
    290};
    291
    292#define GET_RXD_BC(x)			GET_BITS_SHIFT((x), 5, 0)
    293#define GET_RXD_RXFQ(x)			GET_BITS_SHIFT((x), 2, 8)
    294#define GET_RXD_TO(x)			GET_BITS_SHIFT((x), 1, 15)
    295#define GET_RXD_TYPE(x)			GET_BITS_SHIFT((x), 4, 16)
    296#define GET_RXD_ERR(x)			GET_BITS_SHIFT((x), 6, 21)
    297#define GET_RXD_RXP(x)			GET_BITS_SHIFT((x), 1, 27)
    298#define GET_RXD_PKT_ID(x)		GET_BITS_SHIFT((x), 3, 28)
    299#define GET_RXD_VTAG(x)			GET_BITS_SHIFT((x), 1, 31)
    300#define GET_RXD_VLAN_ID(x)		GET_BITS_SHIFT((x), 12, 0)
    301#define GET_RXD_VLAN_TCI(x)		GET_BITS_SHIFT((x), 16, 0)
    302#define GET_RXD_CFI(x)			GET_BITS_SHIFT((x), 1, 12)
    303#define GET_RXD_PRIO(x)			GET_BITS_SHIFT((x), 3, 13)
    304
    305struct rxd_desc {
    306	u32 rxd_val1;
    307	u16 len;
    308	u16 rxd_vlan;
    309	u32 va_lo;
    310	u32 va_hi;
    311};
    312
    313/* PBL describes each virtual buffer to be */
    314/* transmitted from the host.*/
    315struct pbl {
    316	u32 pa_lo;
    317	u32 pa_hi;
    318	u32 len;
    319};
    320
    321/* First word for TXD descriptor. It means: type = 3 for regular Tx packet,
    322 * hw_csum = 7 for ip+udp+tcp hw checksums */
    323#define TXD_W1_VAL(bc, checksum, vtag, lgsnd, vlan_id)	\
    324	((bc) | ((checksum)<<5) | ((vtag)<<8) | \
    325	((lgsnd)<<9) | (0x30000) | ((vlan_id)<<20))
    326
    327struct txd_desc {
    328	u32 txd_val1;
    329	u16 mss;
    330	u16 length;
    331	u32 va_lo;
    332	u32 va_hi;
    333	struct pbl pbl[];	/* Fragments */
    334} __packed;
    335
    336/* Register region size */
    337#define BDX_REGS_SIZE	  0x1000
    338
    339/* Registers from 0x0000-0x00fc were remapped to 0x4000-0x40fc */
    340#define regTXD_CFG1_0   0x4000
    341#define regRXF_CFG1_0   0x4010
    342#define regRXD_CFG1_0   0x4020
    343#define regTXF_CFG1_0   0x4030
    344#define regTXD_CFG0_0   0x4040
    345#define regRXF_CFG0_0   0x4050
    346#define regRXD_CFG0_0   0x4060
    347#define regTXF_CFG0_0   0x4070
    348#define regTXD_WPTR_0   0x4080
    349#define regRXF_WPTR_0   0x4090
    350#define regRXD_WPTR_0   0x40A0
    351#define regTXF_WPTR_0   0x40B0
    352#define regTXD_RPTR_0   0x40C0
    353#define regRXF_RPTR_0   0x40D0
    354#define regRXD_RPTR_0   0x40E0
    355#define regTXF_RPTR_0   0x40F0
    356#define regTXF_RPTR_3   0x40FC
    357
    358/* hardware versioning */
    359#define  FW_VER         0x5010
    360#define  SROM_VER       0x5020
    361#define  FPGA_VER       0x5030
    362#define  FPGA_SEED      0x5040
    363
    364/* Registers from 0x0100-0x0150 were remapped to 0x5100-0x5150 */
    365#define regISR regISR0
    366#define regISR0          0x5100
    367
    368#define regIMR regIMR0
    369#define regIMR0          0x5110
    370
    371#define regRDINTCM0      0x5120
    372#define regRDINTCM2      0x5128
    373
    374#define regTDINTCM0      0x5130
    375
    376#define regISR_MSK0      0x5140
    377
    378#define regINIT_SEMAPHORE 0x5170
    379#define regINIT_STATUS    0x5180
    380
    381#define regMAC_LNK_STAT  0x0200
    382#define MAC_LINK_STAT    0x4	/* Link state */
    383
    384#define regGMAC_RXF_A   0x1240
    385
    386#define regUNC_MAC0_A   0x1250
    387#define regUNC_MAC1_A   0x1260
    388#define regUNC_MAC2_A   0x1270
    389
    390#define regVLAN_0       0x1800
    391
    392#define regMAX_FRAME_A  0x12C0
    393
    394#define regRX_MAC_MCST0    0x1A80
    395#define regRX_MAC_MCST1    0x1A84
    396#define MAC_MCST_NUM       15
    397#define regRX_MCST_HASH0   0x1A00
    398#define MAC_MCST_HASH_NUM  8
    399
    400#define regVPC                  0x2300
    401#define regVIC                  0x2320
    402#define regVGLB                 0x2340
    403
    404#define regCLKPLL               0x5000
    405
    406/*for 10G only*/
    407#define regREVISION        0x6000
    408#define regSCRATCH         0x6004
    409#define regCTRLST          0x6008
    410#define regMAC_ADDR_0      0x600C
    411#define regMAC_ADDR_1      0x6010
    412#define regFRM_LENGTH      0x6014
    413#define regPAUSE_QUANT     0x6018
    414#define regRX_FIFO_SECTION 0x601C
    415#define regTX_FIFO_SECTION 0x6020
    416#define regRX_FULLNESS     0x6024
    417#define regTX_FULLNESS     0x6028
    418#define regHASHTABLE       0x602C
    419#define regMDIO_ST         0x6030
    420#define regMDIO_CTL        0x6034
    421#define regMDIO_DATA       0x6038
    422#define regMDIO_ADDR       0x603C
    423
    424#define regRST_PORT        0x7000
    425#define regDIS_PORT        0x7010
    426#define regRST_QU          0x7020
    427#define regDIS_QU          0x7030
    428
    429#define regCTRLST_TX_ENA   0x0001
    430#define regCTRLST_RX_ENA   0x0002
    431#define regCTRLST_PRM_ENA  0x0010
    432#define regCTRLST_PAD_ENA  0x0020
    433
    434#define regCTRLST_BASE     (regCTRLST_PAD_ENA|regCTRLST_PRM_ENA)
    435
    436#define regRX_FLT   0x1400
    437
    438/* TXD TXF RXF RXD  CONFIG 0x0000 --- 0x007c*/
    439#define  TX_RX_CFG1_BASE          0xffffffff	/*0-31 */
    440#define  TX_RX_CFG0_BASE          0xfffff000	/*31:12 */
    441#define  TX_RX_CFG0_RSVD          0x0ffc	/*11:2 */
    442#define  TX_RX_CFG0_SIZE          0x0003	/*1:0 */
    443
    444/*  TXD TXF RXF RXD  WRITE 0x0080 --- 0x00BC */
    445#define  TXF_WPTR_WR_PTR        0x7ff8	/*14:3 */
    446
    447/*  TXD TXF RXF RXD  READ  0x00CO --- 0x00FC */
    448#define  TXF_RPTR_RD_PTR        0x7ff8	/*14:3 */
    449
    450#define TXF_WPTR_MASK 0x7ff0	/* last 4 bits are dropped
    451				 * size is rounded to 16 */
    452
    453/*  regISR 0x0100 */
    454/*  regIMR 0x0110 */
    455#define  IMR_INPROG   0x80000000	/*31 */
    456#define  IR_LNKCHG1   0x10000000	/*28 */
    457#define  IR_LNKCHG0   0x08000000	/*27 */
    458#define  IR_GPIO      0x04000000	/*26 */
    459#define  IR_RFRSH     0x02000000	/*25 */
    460#define  IR_RSVD      0x01000000	/*24 */
    461#define  IR_SWI       0x00800000	/*23 */
    462#define  IR_RX_FREE_3 0x00400000	/*22 */
    463#define  IR_RX_FREE_2 0x00200000	/*21 */
    464#define  IR_RX_FREE_1 0x00100000	/*20 */
    465#define  IR_RX_FREE_0 0x00080000	/*19 */
    466#define  IR_TX_FREE_3 0x00040000	/*18 */
    467#define  IR_TX_FREE_2 0x00020000	/*17 */
    468#define  IR_TX_FREE_1 0x00010000	/*16 */
    469#define  IR_TX_FREE_0 0x00008000	/*15 */
    470#define  IR_RX_DESC_3 0x00004000	/*14 */
    471#define  IR_RX_DESC_2 0x00002000	/*13 */
    472#define  IR_RX_DESC_1 0x00001000	/*12 */
    473#define  IR_RX_DESC_0 0x00000800	/*11 */
    474#define  IR_PSE       0x00000400	/*10 */
    475#define  IR_TMR3      0x00000200	/*9 */
    476#define  IR_TMR2      0x00000100	/*8 */
    477#define  IR_TMR1      0x00000080	/*7 */
    478#define  IR_TMR0      0x00000040	/*6 */
    479#define  IR_VNT       0x00000020	/*5 */
    480#define  IR_RxFL      0x00000010	/*4 */
    481#define  IR_SDPERR    0x00000008	/*3 */
    482#define  IR_TR        0x00000004	/*2 */
    483#define  IR_PCIE_LINK 0x00000002	/*1 */
    484#define  IR_PCIE_TOUT 0x00000001	/*0 */
    485
    486#define  IR_EXTRA (IR_RX_FREE_0 | IR_LNKCHG0 | IR_PSE | \
    487    IR_TMR0 | IR_PCIE_LINK | IR_PCIE_TOUT)
    488#define  IR_RUN (IR_EXTRA | IR_RX_DESC_0 | IR_TX_FREE_0)
    489#define  IR_ALL 0xfdfffff7
    490
    491#define  IR_LNKCHG0_ofst        27
    492
    493#define  GMAC_RX_FILTER_OSEN  0x1000	/* shared OS enable */
    494#define  GMAC_RX_FILTER_TXFC  0x0400	/* Tx flow control */
    495#define  GMAC_RX_FILTER_RSV0  0x0200	/* reserved */
    496#define  GMAC_RX_FILTER_FDA   0x0100	/* filter out direct address */
    497#define  GMAC_RX_FILTER_AOF   0x0080	/* accept over run */
    498#define  GMAC_RX_FILTER_ACF   0x0040	/* accept control frames */
    499#define  GMAC_RX_FILTER_ARUNT 0x0020	/* accept under run */
    500#define  GMAC_RX_FILTER_ACRC  0x0010	/* accept crc error */
    501#define  GMAC_RX_FILTER_AM    0x0008	/* accept multicast */
    502#define  GMAC_RX_FILTER_AB    0x0004	/* accept broadcast */
    503#define  GMAC_RX_FILTER_PRM   0x0001	/* [0:1] promiscuous mode */
    504
    505#define  MAX_FRAME_AB_VAL       0x3fff	/* 13:0 */
    506
    507#define  CLKPLL_PLLLKD          0x0200	/*9 */
    508#define  CLKPLL_RSTEND          0x0100	/*8 */
    509#define  CLKPLL_SFTRST          0x0001	/*0 */
    510
    511#define  CLKPLL_LKD             (CLKPLL_PLLLKD|CLKPLL_RSTEND)
    512
    513/*
    514 * PCI-E Device Control Register (Offset 0x88)
    515 * Source: Luxor Data Sheet, 7.1.3.3.3
    516 */
    517#define PCI_DEV_CTRL_REG 0x88
    518#define GET_DEV_CTRL_MAXPL(x)           GET_BITS_SHIFT(x, 3, 5)
    519#define GET_DEV_CTRL_MRRS(x)            GET_BITS_SHIFT(x, 3, 12)
    520
    521/*
    522 * PCI-E Link Status Register (Offset 0x92)
    523 * Source: Luxor Data Sheet, 7.1.3.3.7
    524 */
    525#define PCI_LINK_STATUS_REG 0x92
    526#define GET_LINK_STATUS_LANES(x)		GET_BITS_SHIFT(x, 6, 4)
    527
    528/* Debugging Macros */
    529
    530#define DBG2(fmt, args...)					\
    531	pr_err("%s:%-5d: " fmt, __func__, __LINE__, ## args)
    532
    533#define BDX_ASSERT(x) BUG_ON(x)
    534
    535#ifdef DEBUG
    536
    537#define ENTER						\
    538do {							\
    539	pr_err("%s:%-5d: ENTER\n", __func__, __LINE__); \
    540} while (0)
    541
    542#define RET(args...)					 \
    543do {							 \
    544	pr_err("%s:%-5d: RETURN\n", __func__, __LINE__); \
    545	return args;					 \
    546} while (0)
    547
    548#define DBG(fmt, args...)					\
    549	pr_err("%s:%-5d: " fmt, __func__, __LINE__, ## args)
    550#else
    551#define ENTER do {  } while (0)
    552#define RET(args...)   return args
    553#define DBG(fmt, args...)			\
    554do {						\
    555	if (0)					\
    556		pr_err(fmt, ##args);		\
    557} while (0)
    558#endif
    559
    560#endif /* _BDX__H */