xref: /openbmc/linux/drivers/scsi/a3000.c (revision afdbbc16134ae2eea612b51cab7545938d266dce)

#include <linux/types.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>

#include <asm/setup.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/amigaints.h>
#include <asm/amigahw.h>
#include <asm/irq.h>

#include "scsi.h"
#include <scsi/scsi_host.h>
#include "wd33c93.h"
#include "a3000.h"

#include <linux/stat.h>


#define DMA(ptr)	((a3000_scsiregs *)((ptr)->base))

static struct Scsi_Host *a3000_host = NULL;

static int a3000_release(struct Scsi_Host *instance);

static irqreturn_t a3000_intr(int irq, void *dummy)
{
	unsigned long flags;
	unsigned int status = DMA(a3000_host)->ISTR;

	if (!(status & ISTR_INT_P))
		return IRQ_NONE;
	if (status & ISTR_INTS) {
		spin_lock_irqsave(a3000_host->host_lock, flags);
		wd33c93_intr(a3000_host);
		spin_unlock_irqrestore(a3000_host->host_lock, flags);
		return IRQ_HANDLED;
	}
	printk("Non-serviced A3000 SCSI-interrupt? ISTR = %02x\n", status);
	return IRQ_NONE;
}

static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
{
	struct WD33C93_hostdata *hdata = shost_priv(a3000_host);
	unsigned short cntr = CNTR_PDMD | CNTR_INTEN;
	unsigned long addr = virt_to_bus(cmd->SCp.ptr);

	/*
	 * if the physical address has the wrong alignment, or if
	 * physical address is bad, or if it is a write and at the
	 * end of a physical memory chunk, then allocate a bounce
	 * buffer
	 */
	if (addr & A3000_XFER_MASK) {
		hdata->dma_bounce_len = (cmd->SCp.this_residual + 511) & ~0x1ff;
		hdata->dma_bounce_buffer = kmalloc(hdata->dma_bounce_len,
						   GFP_KERNEL);

		/* can't allocate memory; use PIO */
		if (!hdata->dma_bounce_buffer) {
			hdata->dma_bounce_len = 0;
			return 1;
		}

		if (!dir_in) {
			/* copy to bounce buffer for a write */
			memcpy(hdata->dma_bounce_buffer, cmd->SCp.ptr,
			       cmd->SCp.this_residual);
		}

		addr = virt_to_bus(hdata->dma_bounce_buffer);
	}

	/* setup dma direction */
	if (!dir_in)
		cntr |= CNTR_DDIR;

	/* remember direction */
	hdata->dma_dir = dir_in;

	DMA(a3000_host)->CNTR = cntr;

	/* setup DMA *physical* address */
	DMA(a3000_host)->ACR = addr;

	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 */
	mb();			/* make sure setup is completed */
	DMA(a3000_host)->ST_DMA = 1;
	mb();			/* make sure DMA has started before next IO */

	/* return success */
	return 0;
}

static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
		     int status)
{
	struct WD33C93_hostdata *hdata = shost_priv(instance);

	/* disable SCSI interrupts */
	unsigned short cntr = CNTR_PDMD;

	if (!hdata->dma_dir)
		cntr |= CNTR_DDIR;

	DMA(instance)->CNTR = cntr;
	mb();			/* make sure CNTR is updated before next IO */

	/* flush if we were reading */
	if (hdata->dma_dir) {
		DMA(instance)->FLUSH = 1;
		mb();		/* don't allow prefetch */
		while (!(DMA(instance)->ISTR & ISTR_FE_FLG))
			barrier();
		mb();		/* no IO until FLUSH is done */
	}

	/* clear a possible interrupt */
	/* I think that this CINT is only necessary if you are
	 * using the terminal count features.   HM 7 Mar 1994
	 */
	DMA(instance)->CINT = 1;

	/* stop DMA */
	DMA(instance)->SP_DMA = 1;
	mb();			/* make sure DMA is stopped before next IO */

	/* restore the CONTROL bits (minus the direction flag) */
	DMA(instance)->CNTR = CNTR_PDMD | CNTR_INTEN;
	mb();			/* make sure CNTR is updated before next IO */

	/* copy from a bounce buffer, if necessary */
	if (status && hdata->dma_bounce_buffer) {
		if (SCpnt) {
			if (hdata->dma_dir && SCpnt)
				memcpy(SCpnt->SCp.ptr,
				       hdata->dma_bounce_buffer,
				       SCpnt->SCp.this_residual);
			kfree(hdata->dma_bounce_buffer);
			hdata->dma_bounce_buffer = NULL;
			hdata->dma_bounce_len = 0;
		} else {
			kfree(hdata->dma_bounce_buffer);
			hdata->dma_bounce_buffer = NULL;
			hdata->dma_bounce_len = 0;
		}
	}
}

static int __init a3000_detect(struct scsi_host_template *tpnt)
{
	wd33c93_regs regs;
	struct WD33C93_hostdata *hdata;

	if (!MACH_IS_AMIGA || !AMIGAHW_PRESENT(A3000_SCSI))
		return 0;
	if (!request_mem_region(0xDD0000, 256, "wd33c93"))
		return 0;

	tpnt->proc_name = "A3000";
	tpnt->proc_info = &wd33c93_proc_info;

	a3000_host = scsi_register(tpnt, sizeof(struct WD33C93_hostdata));
	if (a3000_host == NULL)
		goto fail_register;

	a3000_host->base = ZTWO_VADDR(0xDD0000);
	a3000_host->irq = IRQ_AMIGA_PORTS;
	DMA(a3000_host)->DAWR = DAWR_A3000;
	regs.SASR = &(DMA(a3000_host)->SASR);
	regs.SCMD = &(DMA(a3000_host)->SCMD);
	hdata = shost_priv(a3000_host);
	hdata->no_sync = 0xff;
	hdata->fast = 0;
	hdata->dma_mode = CTRL_DMA;
	wd33c93_init(a3000_host, regs, dma_setup, dma_stop, WD33C93_FS_12_15);
	if (request_irq(IRQ_AMIGA_PORTS, a3000_intr, IRQF_SHARED, "A3000 SCSI",
			a3000_intr))
		goto fail_irq;
	DMA(a3000_host)->CNTR = CNTR_PDMD | CNTR_INTEN;

	return 1;

fail_irq:
	scsi_unregister(a3000_host);
fail_register:
	release_mem_region(0xDD0000, 256);
	return 0;
}

static int a3000_bus_reset(struct scsi_cmnd *cmd)
{
	/* FIXME perform bus-specific reset */

	/* FIXME 2: kill this entire function, which should
	   cause mid-layer to call wd33c93_host_reset anyway? */

	spin_lock_irq(cmd->device->host->host_lock);
	wd33c93_host_reset(cmd);
	spin_unlock_irq(cmd->device->host->host_lock);

	return SUCCESS;
}

#define HOSTS_C

static struct scsi_host_template driver_template = {
	.proc_name		= "A3000",
	.name			= "Amiga 3000 built-in SCSI",
	.detect			= a3000_detect,
	.release		= a3000_release,
	.queuecommand		= wd33c93_queuecommand,
	.eh_abort_handler	= wd33c93_abort,
	.eh_bus_reset_handler	= a3000_bus_reset,
	.eh_host_reset_handler	= wd33c93_host_reset,
	.can_queue		= CAN_QUEUE,
	.this_id		= 7,
	.sg_tablesize		= SG_ALL,
	.cmd_per_lun		= CMD_PER_LUN,
	.use_clustering		= ENABLE_CLUSTERING
};


#include "scsi_module.c"

static int a3000_release(struct Scsi_Host *instance)
{
	DMA(instance)->CNTR = 0;
	release_mem_region(0xDD0000, 256);
	free_irq(IRQ_AMIGA_PORTS, a3000_intr);
	return 1;
}

MODULE_LICENSE("GPL");