drivers/dma/bestcomm/ata.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Bestcomm ATA task driver
   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
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/types.h>
  15 #include <asm/io.h>
  16
  17 #include <linux/fsl/bestcomm/bestcomm.h>
  18 #include <linux/fsl/bestcomm/bestcomm_priv.h>
  19 #include <linux/fsl/bestcomm/ata.h>
  20
  21
  22 /* ======================================================================== */
  23 /* Task image/var/inc                                                       */
  24 /* ======================================================================== */
  25
  26 /* ata task image */
  27 extern u32 bcom_ata_task[];
  28
  29 /* ata task vars that need to be set before enabling the task */
  30 struct bcom_ata_var {
  31         u32 enable;             /* (u16*) address of task's control register */
  32         u32 bd_base;            /* (struct bcom_bd*) beginning of ring buffer */
  33         u32 bd_last;            /* (struct bcom_bd*) end of ring buffer */
  34         u32 bd_start;           /* (struct bcom_bd*) current bd */
  35         u32 buffer_size;        /* size of receive buffer */
  36 };
  37
  38 /* ata task incs that need to be set before enabling the task */
  39 struct bcom_ata_inc {
  40         u16 pad0;
  41         s16 incr_bytes;
  42         u16 pad1;
  43         s16 incr_dst;
  44         u16 pad2;
  45         s16 incr_src;
  46 };
  47
  48
  49 /* ======================================================================== */
  50 /* Task support code                                                        */
  51 /* ======================================================================== */
  52
  53 struct bcom_task *
  54 bcom_ata_init(int queue_len, int maxbufsize)
  55 {
  56         struct bcom_task *tsk;
  57         struct bcom_ata_var *var;
  58         struct bcom_ata_inc *inc;
  59
  60         /* Prefetch breaks ATA DMA.  Turn it off for ATA DMA */
  61         bcom_disable_prefetch();
  62
  63         tsk = bcom_task_alloc(queue_len, sizeof(struct bcom_ata_bd), 0);
  64         if (!tsk)
  65                 return NULL;
  66
  67         tsk->flags = BCOM_FLAGS_NONE;
  68
  69         bcom_ata_reset_bd(tsk);
  70
  71         var = (struct bcom_ata_var *) bcom_task_var(tsk->tasknum);
  72         inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
  73
  74         if (bcom_load_image(tsk->tasknum, bcom_ata_task)) {
  75                 bcom_task_free(tsk);
  76                 return NULL;
  77         }
  78
  79         var->enable     = bcom_eng->regs_base +
  80                                 offsetof(struct mpc52xx_sdma, tcr[tsk->tasknum]);
  81         var->bd_base    = tsk->bd_pa;
  82         var->bd_last    = tsk->bd_pa + ((tsk->num_bd-1) * tsk->bd_size);
  83         var->bd_start   = tsk->bd_pa;
  84         var->buffer_size = maxbufsize;
  85
  86         /* Configure some stuff */
  87         bcom_set_task_pragma(tsk->tasknum, BCOM_ATA_PRAGMA);
  88         bcom_set_task_auto_start(tsk->tasknum, tsk->tasknum);
  89
  90         out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ATA_RX], BCOM_IPR_ATA_RX);
  91         out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ATA_TX], BCOM_IPR_ATA_TX);
  92
  93         out_be32(&bcom_eng->regs->IntPend, 1<<tsk->tasknum); /* Clear ints */
  94
  95         return tsk;
  96 }
  97 EXPORT_SYMBOL_GPL(bcom_ata_init);
  98
  99 void bcom_ata_rx_prepare(struct bcom_task *tsk)
 100 {
 101         struct bcom_ata_inc *inc;
 102
 103         inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
 104
 105         inc->incr_bytes = -(s16)sizeof(u32);
 106         inc->incr_src   = 0;
 107         inc->incr_dst   = sizeof(u32);
 108
 109         bcom_set_initiator(tsk->tasknum, BCOM_INITIATOR_ATA_RX);
 110 }
 111 EXPORT_SYMBOL_GPL(bcom_ata_rx_prepare);
 112
 113 void bcom_ata_tx_prepare(struct bcom_task *tsk)
 114 {
 115         struct bcom_ata_inc *inc;
 116
 117         inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
 118
 119         inc->incr_bytes = -(s16)sizeof(u32);
 120         inc->incr_src   = sizeof(u32);
 121         inc->incr_dst   = 0;
 122
 123         bcom_set_initiator(tsk->tasknum, BCOM_INITIATOR_ATA_TX);
 124 }
 125 EXPORT_SYMBOL_GPL(bcom_ata_tx_prepare);
 126
 127 void bcom_ata_reset_bd(struct bcom_task *tsk)
 128 {
 129         struct bcom_ata_var *var;
 130
 131         /* Reset all BD */
 132         memset_io(tsk->bd, 0x00, tsk->num_bd * tsk->bd_size);
 133
 134         tsk->index = 0;
 135         tsk->outdex = 0;
 136
 137         var = (struct bcom_ata_var *) bcom_task_var(tsk->tasknum);
 138         var->bd_start = var->bd_base;
 139 }
 140 EXPORT_SYMBOL_GPL(bcom_ata_reset_bd);
 141
 142 void bcom_ata_release(struct bcom_task *tsk)
 143 {
 144         /* Nothing special for the ATA tasks */
 145         bcom_task_free(tsk);
 146 }
 147 EXPORT_SYMBOL_GPL(bcom_ata_release);
 148
 149
 150 MODULE_DESCRIPTION("BestComm ATA task driver");
 151 MODULE_AUTHOR("John Rigby");
 152 MODULE_LICENSE("GPL v2");