linux/drivers/scsi/mvme147.c
Christoph Hellwig 2a3d4eb8e2 scsi: flip the default on use_clustering
Most SCSI drivers want to enable "clustering", that is merging of
segments so that they might span more than a single page.  Remove the
ENABLE_CLUSTERING define, and require drivers to explicitly set
DISABLE_CLUSTERING to disable this feature.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-12-18 23:13:12 -05:00

158 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/blkdev.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/mvme147hw.h>
#include <asm/irq.h>
#include "scsi.h"
#include <scsi/scsi_host.h>
#include "wd33c93.h"
#include "mvme147.h"
static irqreturn_t mvme147_intr(int irq, void *data)
{
struct Scsi_Host *instance = data;
if (irq == MVME147_IRQ_SCSI_PORT)
wd33c93_intr(instance);
else
m147_pcc->dma_intr = 0x89; /* Ack and enable ints */
return IRQ_HANDLED;
}
static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
{
struct Scsi_Host *instance = cmd->device->host;
struct WD33C93_hostdata *hdata = shost_priv(instance);
unsigned char flags = 0x01;
unsigned long addr = virt_to_bus(cmd->SCp.ptr);
/* setup dma direction */
if (!dir_in)
flags |= 0x04;
/* remember direction */
hdata->dma_dir = dir_in;
if (dir_in) {
/* invalidate any cache */
cache_clear(addr, cmd->SCp.this_residual);
} else {
/* push any dirty cache */
cache_push(addr, cmd->SCp.this_residual);
}
/* start DMA */
m147_pcc->dma_bcr = cmd->SCp.this_residual | (1 << 24);
m147_pcc->dma_dadr = addr;
m147_pcc->dma_cntrl = flags;
/* return success */
return 0;
}
static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
int status)
{
m147_pcc->dma_cntrl = 0;
}
static struct scsi_host_template mvme147_host_template = {
.module = THIS_MODULE,
.proc_name = "MVME147",
.name = "MVME147 built-in SCSI",
.queuecommand = wd33c93_queuecommand,
.eh_abort_handler = wd33c93_abort,
.eh_host_reset_handler = wd33c93_host_reset,
.show_info = wd33c93_show_info,
.write_info = wd33c93_write_info,
.can_queue = CAN_QUEUE,
.this_id = 7,
.sg_tablesize = SG_ALL,
.cmd_per_lun = CMD_PER_LUN,
};
static struct Scsi_Host *mvme147_shost;
static int __init mvme147_init(void)
{
wd33c93_regs regs;
struct WD33C93_hostdata *hdata;
int error = -ENOMEM;
if (!MACH_IS_MVME147)
return 0;
mvme147_shost = scsi_host_alloc(&mvme147_host_template,
sizeof(struct WD33C93_hostdata));
if (!mvme147_shost)
goto err_out;
mvme147_shost->base = 0xfffe4000;
mvme147_shost->irq = MVME147_IRQ_SCSI_PORT;
regs.SASR = (volatile unsigned char *)0xfffe4000;
regs.SCMD = (volatile unsigned char *)0xfffe4001;
hdata = shost_priv(mvme147_shost);
hdata->no_sync = 0xff;
hdata->fast = 0;
hdata->dma_mode = CTRL_DMA;
wd33c93_init(mvme147_shost, regs, dma_setup, dma_stop, WD33C93_FS_8_10);
error = request_irq(MVME147_IRQ_SCSI_PORT, mvme147_intr, 0,
"MVME147 SCSI PORT", mvme147_shost);
if (error)
goto err_unregister;
error = request_irq(MVME147_IRQ_SCSI_DMA, mvme147_intr, 0,
"MVME147 SCSI DMA", mvme147_shost);
if (error)
goto err_free_irq;
#if 0 /* Disabled; causes problems booting */
m147_pcc->scsi_interrupt = 0x10; /* Assert SCSI bus reset */
udelay(100);
m147_pcc->scsi_interrupt = 0x00; /* Negate SCSI bus reset */
udelay(2000);
m147_pcc->scsi_interrupt = 0x40; /* Clear bus reset interrupt */
#endif
m147_pcc->scsi_interrupt = 0x09; /* Enable interrupt */
m147_pcc->dma_cntrl = 0x00; /* ensure DMA is stopped */
m147_pcc->dma_intr = 0x89; /* Ack and enable ints */
error = scsi_add_host(mvme147_shost, NULL);
if (error)
goto err_free_irq;
scsi_scan_host(mvme147_shost);
return 0;
err_free_irq:
free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
err_unregister:
scsi_host_put(mvme147_shost);
err_out:
return error;
}
static void __exit mvme147_exit(void)
{
scsi_remove_host(mvme147_shost);
/* XXX Make sure DMA is stopped! */
free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
free_irq(MVME147_IRQ_SCSI_DMA, mvme147_shost);
scsi_host_put(mvme147_shost);
}
module_init(mvme147_init);
module_exit(mvme147_exit);