dma/bestcomm/ata.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Bestcomm ATA task driver
0004  *
0005  * Patterned after bestcomm/fec.c by Dale Farnsworth <dfarnsworth@mvista.com>
0006  *                                   2003-2004 (c) MontaVista, Software, Inc.
0007  *
0008  * Copyright (C) 2006-2007 Sylvain Munaut <tnt@246tNt.com>
0009  * Copyright (C) 2006      Freescale - John Rigby
0010  */
0011
0012 #include <linux/kernel.h>
0013 #include <linux/module.h>
0014 #include <linux/types.h>
0015 #include <asm/io.h>
0016
0017 #include <linux/fsl/bestcomm/bestcomm.h>
0018 #include <linux/fsl/bestcomm/bestcomm_priv.h>
0019 #include <linux/fsl/bestcomm/ata.h>
0020
0021
0022 /* ======================================================================== */
0023 /* Task image/var/inc                                                       */
0024 /* ======================================================================== */
0025
0026 /* ata task image */
0027 extern u32 bcom_ata_task[];
0028
0029 /* ata task vars that need to be set before enabling the task */
0030 struct bcom_ata_var {
0031     u32 enable;     /* (u16*) address of task's control register */
0032     u32 bd_base;        /* (struct bcom_bd*) beginning of ring buffer */
0033     u32 bd_last;        /* (struct bcom_bd*) end of ring buffer */
0034     u32 bd_start;       /* (struct bcom_bd*) current bd */
0035     u32 buffer_size;    /* size of receive buffer */
0036 };
0037
0038 /* ata task incs that need to be set before enabling the task */
0039 struct bcom_ata_inc {
0040     u16 pad0;
0041     s16 incr_bytes;
0042     u16 pad1;
0043     s16 incr_dst;
0044     u16 pad2;
0045     s16 incr_src;
0046 };
0047
0048
0049 /* ======================================================================== */
0050 /* Task support code                                                        */
0051 /* ======================================================================== */
0052
0053 struct bcom_task *
0054 bcom_ata_init(int queue_len, int maxbufsize)
0055 {
0056     struct bcom_task *tsk;
0057     struct bcom_ata_var *var;
0058     struct bcom_ata_inc *inc;
0059
0060     /* Prefetch breaks ATA DMA.  Turn it off for ATA DMA */
0061     bcom_disable_prefetch();
0062
0063     tsk = bcom_task_alloc(queue_len, sizeof(struct bcom_ata_bd), 0);
0064     if (!tsk)
0065         return NULL;
0066
0067     tsk->flags = BCOM_FLAGS_NONE;
0068
0069     bcom_ata_reset_bd(tsk);
0070
0071     var = (struct bcom_ata_var *) bcom_task_var(tsk->tasknum);
0072     inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
0073
0074     if (bcom_load_image(tsk->tasknum, bcom_ata_task)) {
0075         bcom_task_free(tsk);
0076         return NULL;
0077     }
0078
0079     var->enable = bcom_eng->regs_base +
0080                 offsetof(struct mpc52xx_sdma, tcr[tsk->tasknum]);
0081     var->bd_base    = tsk->bd_pa;
0082     var->bd_last    = tsk->bd_pa + ((tsk->num_bd-1) * tsk->bd_size);
0083     var->bd_start   = tsk->bd_pa;
0084     var->buffer_size = maxbufsize;
0085
0086     /* Configure some stuff */
0087     bcom_set_task_pragma(tsk->tasknum, BCOM_ATA_PRAGMA);
0088     bcom_set_task_auto_start(tsk->tasknum, tsk->tasknum);
0089
0090     out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ATA_RX], BCOM_IPR_ATA_RX);
0091     out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ATA_TX], BCOM_IPR_ATA_TX);
0092
0093     out_be32(&bcom_eng->regs->IntPend, 1<<tsk->tasknum); /* Clear ints */
0094
0095     return tsk;
0096 }
0097 EXPORT_SYMBOL_GPL(bcom_ata_init);
0098
0099 void bcom_ata_rx_prepare(struct bcom_task *tsk)
0100 {
0101     struct bcom_ata_inc *inc;
0102
0103     inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
0104
0105     inc->incr_bytes = -(s16)sizeof(u32);
0106     inc->incr_src   = 0;
0107     inc->incr_dst   = sizeof(u32);
0108
0109     bcom_set_initiator(tsk->tasknum, BCOM_INITIATOR_ATA_RX);
0110 }
0111 EXPORT_SYMBOL_GPL(bcom_ata_rx_prepare);
0112
0113 void bcom_ata_tx_prepare(struct bcom_task *tsk)
0114 {
0115     struct bcom_ata_inc *inc;
0116
0117     inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
0118
0119     inc->incr_bytes = -(s16)sizeof(u32);
0120     inc->incr_src   = sizeof(u32);
0121     inc->incr_dst   = 0;
0122
0123     bcom_set_initiator(tsk->tasknum, BCOM_INITIATOR_ATA_TX);
0124 }
0125 EXPORT_SYMBOL_GPL(bcom_ata_tx_prepare);
0126
0127 void bcom_ata_reset_bd(struct bcom_task *tsk)
0128 {
0129     struct bcom_ata_var *var;
0130
0131     /* Reset all BD */
0132     memset_io(tsk->bd, 0x00, tsk->num_bd * tsk->bd_size);
0133
0134     tsk->index = 0;
0135     tsk->outdex = 0;
0136
0137     var = (struct bcom_ata_var *) bcom_task_var(tsk->tasknum);
0138     var->bd_start = var->bd_base;
0139 }
0140 EXPORT_SYMBOL_GPL(bcom_ata_reset_bd);
0141
0142 void bcom_ata_release(struct bcom_task *tsk)
0143 {
0144     /* Nothing special for the ATA tasks */
0145     bcom_task_free(tsk);
0146 }
0147 EXPORT_SYMBOL_GPL(bcom_ata_release);
0148
0149
0150 MODULE_DESCRIPTION("BestComm ATA task driver");
0151 MODULE_AUTHOR("John Rigby");
0152 MODULE_LICENSE("GPL v2");