kernel/drivers/dma/bestcomm/ata.c

   1 /*
   2  * Bestcomm ATA task driver
   3  *
   4  *
   5  * Patterned after bestcomm/fec.c by Dale Farnsworth <dfarnsworth@mvista.com>
   6  *                                   2003-2004 (c) MontaVista, Software, Inc.
   7  *
   8  * Copyright (C) 2006-2007 Sylvain Munaut <tnt@246tNt.com>
   9  * Copyright (C) 2006      Freescale - John Rigby
  10  *
  11  * This file is licensed under the terms of the GNU General Public License
  12  * version 2. This program is licensed "as is" without any warranty of any
  13  * kind, whether express or implied.
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/types.h>
  19 #include <asm/io.h>
  20
  21 #include <linux/fsl/bestcomm/bestcomm.h>
  22 #include <linux/fsl/bestcomm/bestcomm_priv.h>
  23 #include <linux/fsl/bestcomm/ata.h>
  24
  25
  26 /* ======================================================================== */
  27 /* Task image/var/inc                                                       */
  28 /* ======================================================================== */
  29
  30 /* ata task image */
  31 extern u32 bcom_ata_task[];
  32
  33 /* ata task vars that need to be set before enabling the task */
  34 struct bcom_ata_var {
  35         u32 enable;             /* (u16*) address of task's control register */
  36         u32 bd_base;            /* (struct bcom_bd*) beginning of ring buffer */
  37         u32 bd_last;            /* (struct bcom_bd*) end of ring buffer */
  38         u32 bd_start;           /* (struct bcom_bd*) current bd */
  39         u32 buffer_size;        /* size of receive buffer */
  40 };
  41
  42 /* ata task incs that need to be set before enabling the task */
  43 struct bcom_ata_inc {
  44         u16 pad0;
  45         s16 incr_bytes;
  46         u16 pad1;
  47         s16 incr_dst;
  48         u16 pad2;
  49         s16 incr_src;
  50 };
  51
  52
  53 /* ======================================================================== */
  54 /* Task support code                                                        */
  55 /* ======================================================================== */
  56
  57 struct bcom_task *
  58 bcom_ata_init(int queue_len, int maxbufsize)
  59 {
  60         struct bcom_task *tsk;
  61         struct bcom_ata_var *var;
  62         struct bcom_ata_inc *inc;
  63
  64         /* Prefetch breaks ATA DMA.  Turn it off for ATA DMA */
  65         bcom_disable_prefetch();
  66
  67         tsk = bcom_task_alloc(queue_len, sizeof(struct bcom_ata_bd), 0);
  68         if (!tsk)
  69                 return NULL;
  70
  71         tsk->flags = BCOM_FLAGS_NONE;
  72
  73         bcom_ata_reset_bd(tsk);
  74
  75         var = (struct bcom_ata_var *) bcom_task_var(tsk->tasknum);
  76         inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
  77
  78         if (bcom_load_image(tsk->tasknum, bcom_ata_task)) {
  79                 bcom_task_free(tsk);
  80                 return NULL;
  81         }
  82
  83         var->enable     = bcom_eng->regs_base +
  84                                 offsetof(struct mpc52xx_sdma, tcr[tsk->tasknum]);
  85         var->bd_base    = tsk->bd_pa;
  86         var->bd_last    = tsk->bd_pa + ((tsk->num_bd-1) * tsk->bd_size);
  87         var->bd_start   = tsk->bd_pa;
  88         var->buffer_size = maxbufsize;
  89
  90         /* Configure some stuff */
  91         bcom_set_task_pragma(tsk->tasknum, BCOM_ATA_PRAGMA);
  92         bcom_set_task_auto_start(tsk->tasknum, tsk->tasknum);
  93
  94         out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ATA_RX], BCOM_IPR_ATA_RX);
  95         out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ATA_TX], BCOM_IPR_ATA_TX);
  96
  97         out_be32(&bcom_eng->regs->IntPend, 1<<tsk->tasknum); /* Clear ints */
  98
  99         return tsk;
 100 }
 101 EXPORT_SYMBOL_GPL(bcom_ata_init);
 102
 103 void bcom_ata_rx_prepare(struct bcom_task *tsk)
 104 {
 105         struct bcom_ata_inc *inc;
 106
 107         inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
 108
 109         inc->incr_bytes = -(s16)sizeof(u32);
 110         inc->incr_src   = 0;
 111         inc->incr_dst   = sizeof(u32);
 112
 113         bcom_set_initiator(tsk->tasknum, BCOM_INITIATOR_ATA_RX);
 114 }
 115 EXPORT_SYMBOL_GPL(bcom_ata_rx_prepare);
 116
 117 void bcom_ata_tx_prepare(struct bcom_task *tsk)
 118 {
 119         struct bcom_ata_inc *inc;
 120
 121         inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
 122
 123         inc->incr_bytes = -(s16)sizeof(u32);
 124         inc->incr_src   = sizeof(u32);
 125         inc->incr_dst   = 0;
 126
 127         bcom_set_initiator(tsk->tasknum, BCOM_INITIATOR_ATA_TX);
 128 }
 129 EXPORT_SYMBOL_GPL(bcom_ata_tx_prepare);
 130
 131 void bcom_ata_reset_bd(struct bcom_task *tsk)
 132 {
 133         struct bcom_ata_var *var;
 134
 135         /* Reset all BD */
 136         memset(tsk->bd, 0x00, tsk->num_bd * tsk->bd_size);
 137
 138         tsk->index = 0;
 139         tsk->outdex = 0;
 140
 141         var = (struct bcom_ata_var *) bcom_task_var(tsk->tasknum);
 142         var->bd_start = var->bd_base;
 143 }
 144 EXPORT_SYMBOL_GPL(bcom_ata_reset_bd);
 145
 146 void bcom_ata_release(struct bcom_task *tsk)
 147 {
 148         /* Nothing special for the ATA tasks */
 149         bcom_task_free(tsk);
 150 }
 151 EXPORT_SYMBOL_GPL(bcom_ata_release);
 152
 153
 154 MODULE_DESCRIPTION("BestComm ATA task driver");
 155 MODULE_AUTHOR("John Rigby");
 156 MODULE_LICENSE("GPL v2");
 157