LXR linux/arch/powerpc/sysdev/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 "bestcomm.h"
  22#include "bestcomm_priv.h"
  23#include "ata.h"
  24
  25
  26/* ======================================================================== */
  27/* Task image/var/inc                                                       */
  28/* ======================================================================== */
  29
  30/* ata task image */
  31extern u32 bcom_ata_task[];
  32
  33/* ata task vars that need to be set before enabling the task */
  34struct 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 */
  43struct 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
  57struct bcom_task *
  58bcom_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}
 101EXPORT_SYMBOL_GPL(bcom_ata_init);
 102
 103void 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}
 115EXPORT_SYMBOL_GPL(bcom_ata_rx_prepare);
 116
 117void 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}
 129EXPORT_SYMBOL_GPL(bcom_ata_tx_prepare);
 130
 131void 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}
 144EXPORT_SYMBOL_GPL(bcom_ata_reset_bd);
 145
 146void bcom_ata_release(struct bcom_task *tsk)
 147{
 148        /* Nothing special for the ATA tasks */
 149        bcom_task_free(tsk);
 150}
 151EXPORT_SYMBOL_GPL(bcom_ata_release);
 152
 153
 154MODULE_DESCRIPTION("BestComm ATA task driver");
 155MODULE_AUTHOR("John Rigby");
 156MODULE_LICENSE("GPL v2");
 157
 158