linux/drivers/dma/bestcomm/ata.c
Anatolij Gustschin adec566b05 dmaengine: bestcomm: fix system boot lockups
memset() and memcpy() on an MMIO region like here results in a
lockup at startup on mpc5200 platform (since this first happens
during probing of the ATA and Ethernet drivers). Use memset_io()
and memcpy_toio() instead.

Fixes: 2f9ea1bde0 ("bestcomm: core bestcomm support for Freescale MPC5200")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Link: https://lore.kernel.org/r/20211014094012.21286-1-agust@denx.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-10-18 11:43:12 +05:30

158 lines
4.2 KiB
C

/*
* Bestcomm ATA task driver
*
*
* Patterned after bestcomm/fec.c by Dale Farnsworth <dfarnsworth@mvista.com>
* 2003-2004 (c) MontaVista, Software, Inc.
*
* Copyright (C) 2006-2007 Sylvain Munaut <tnt@246tNt.com>
* Copyright (C) 2006 Freescale - John Rigby
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <asm/io.h>
#include <linux/fsl/bestcomm/bestcomm.h>
#include <linux/fsl/bestcomm/bestcomm_priv.h>
#include <linux/fsl/bestcomm/ata.h>
/* ======================================================================== */
/* Task image/var/inc */
/* ======================================================================== */
/* ata task image */
extern u32 bcom_ata_task[];
/* ata task vars that need to be set before enabling the task */
struct bcom_ata_var {
u32 enable; /* (u16*) address of task's control register */
u32 bd_base; /* (struct bcom_bd*) beginning of ring buffer */
u32 bd_last; /* (struct bcom_bd*) end of ring buffer */
u32 bd_start; /* (struct bcom_bd*) current bd */
u32 buffer_size; /* size of receive buffer */
};
/* ata task incs that need to be set before enabling the task */
struct bcom_ata_inc {
u16 pad0;
s16 incr_bytes;
u16 pad1;
s16 incr_dst;
u16 pad2;
s16 incr_src;
};
/* ======================================================================== */
/* Task support code */
/* ======================================================================== */
struct bcom_task *
bcom_ata_init(int queue_len, int maxbufsize)
{
struct bcom_task *tsk;
struct bcom_ata_var *var;
struct bcom_ata_inc *inc;
/* Prefetch breaks ATA DMA. Turn it off for ATA DMA */
bcom_disable_prefetch();
tsk = bcom_task_alloc(queue_len, sizeof(struct bcom_ata_bd), 0);
if (!tsk)
return NULL;
tsk->flags = BCOM_FLAGS_NONE;
bcom_ata_reset_bd(tsk);
var = (struct bcom_ata_var *) bcom_task_var(tsk->tasknum);
inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
if (bcom_load_image(tsk->tasknum, bcom_ata_task)) {
bcom_task_free(tsk);
return NULL;
}
var->enable = bcom_eng->regs_base +
offsetof(struct mpc52xx_sdma, tcr[tsk->tasknum]);
var->bd_base = tsk->bd_pa;
var->bd_last = tsk->bd_pa + ((tsk->num_bd-1) * tsk->bd_size);
var->bd_start = tsk->bd_pa;
var->buffer_size = maxbufsize;
/* Configure some stuff */
bcom_set_task_pragma(tsk->tasknum, BCOM_ATA_PRAGMA);
bcom_set_task_auto_start(tsk->tasknum, tsk->tasknum);
out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ATA_RX], BCOM_IPR_ATA_RX);
out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ATA_TX], BCOM_IPR_ATA_TX);
out_be32(&bcom_eng->regs->IntPend, 1<<tsk->tasknum); /* Clear ints */
return tsk;
}
EXPORT_SYMBOL_GPL(bcom_ata_init);
void bcom_ata_rx_prepare(struct bcom_task *tsk)
{
struct bcom_ata_inc *inc;
inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
inc->incr_bytes = -(s16)sizeof(u32);
inc->incr_src = 0;
inc->incr_dst = sizeof(u32);
bcom_set_initiator(tsk->tasknum, BCOM_INITIATOR_ATA_RX);
}
EXPORT_SYMBOL_GPL(bcom_ata_rx_prepare);
void bcom_ata_tx_prepare(struct bcom_task *tsk)
{
struct bcom_ata_inc *inc;
inc = (struct bcom_ata_inc *) bcom_task_inc(tsk->tasknum);
inc->incr_bytes = -(s16)sizeof(u32);
inc->incr_src = sizeof(u32);
inc->incr_dst = 0;
bcom_set_initiator(tsk->tasknum, BCOM_INITIATOR_ATA_TX);
}
EXPORT_SYMBOL_GPL(bcom_ata_tx_prepare);
void bcom_ata_reset_bd(struct bcom_task *tsk)
{
struct bcom_ata_var *var;
/* Reset all BD */
memset_io(tsk->bd, 0x00, tsk->num_bd * tsk->bd_size);
tsk->index = 0;
tsk->outdex = 0;
var = (struct bcom_ata_var *) bcom_task_var(tsk->tasknum);
var->bd_start = var->bd_base;
}
EXPORT_SYMBOL_GPL(bcom_ata_reset_bd);
void bcom_ata_release(struct bcom_task *tsk)
{
/* Nothing special for the ATA tasks */
bcom_task_free(tsk);
}
EXPORT_SYMBOL_GPL(bcom_ata_release);
MODULE_DESCRIPTION("BestComm ATA task driver");
MODULE_AUTHOR("John Rigby");
MODULE_LICENSE("GPL v2");