linux-hardened/drivers/scsi/sgiwd93.c
peter fuerst 8f3334edae [SCSI] sgiwd93: interfacing to wd33c93
1) sgiwd93 used to switch off asynchronous mode on the wd33c93, discarding
   any "nosync"-requests from the commandline.
   But we need to allow "nosync"-requests for selected devices, for example
   the Pioneer DVD305S.
   (For the curious: this device accepts the SDTR from wd33c93 and success-
   fully sends inquiry data in sync mode, but after the data phase in the
   inquiry command does an unexpected disconnect, seemingly sending no
   "status" or "command complete". Forcing async transfers makes it work
   together flawlessly with the wd33c93. Of course, preferable would be, to
   implement wd33c93's "resume command" stuff, but that probably will not
   come soon.)

2) Maximize benefit from the preceding Fast SCSI patch for wd33c93 by passing
   the higher input-clock frequency explicitely. To be applied after the
   mentioned wd33c93 patch.

Signed-off-by: peter fuerst <post@pfrst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-02-16 09:38:12 -06:00

343 lines
8.4 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
* Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
* Copyright (C) 2001 Florian Lohoff (flo@rfc822.org)
* Copyright (C) 2003 Ralf Baechle (ralf@linux-mips.org)
*
* (In all truth, Jed Schimmel wrote all this code.)
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/spinlock.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/sgialib.h>
#include <asm/sgi/sgi.h>
#include <asm/sgi/mc.h>
#include <asm/sgi/hpc3.h>
#include <asm/sgi/ip22.h>
#include <asm/irq.h>
#include <asm/io.h>
#include "scsi.h"
#include <scsi/scsi_host.h>
#include "wd33c93.h"
#include <linux/stat.h>
#if 0
#define DPRINTK(args...) printk(args)
#else
#define DPRINTK(args...)
#endif
#define HDATA(ptr) ((struct ip22_hostdata *)((ptr)->hostdata))
struct ip22_hostdata {
struct WD33C93_hostdata wh;
struct hpc_data {
dma_addr_t dma;
void * cpu;
} hd;
};
struct hpc_chunk {
struct hpc_dma_desc desc;
u32 _padding; /* align to quadword boundary */
};
struct Scsi_Host *sgiwd93_host;
struct Scsi_Host *sgiwd93_host1;
/* Wuff wuff, wuff, wd33c93.c, wuff wuff, object oriented, bow wow. */
static inline void write_wd33c93_count(const wd33c93_regs regs,
unsigned long value)
{
*regs.SASR = WD_TRANSFER_COUNT_MSB;
mb();
*regs.SCMD = ((value >> 16) & 0xff);
*regs.SCMD = ((value >> 8) & 0xff);
*regs.SCMD = ((value >> 0) & 0xff);
mb();
}
static inline unsigned long read_wd33c93_count(const wd33c93_regs regs)
{
unsigned long value;
*regs.SASR = WD_TRANSFER_COUNT_MSB;
mb();
value = ((*regs.SCMD & 0xff) << 16);
value |= ((*regs.SCMD & 0xff) << 8);
value |= ((*regs.SCMD & 0xff) << 0);
mb();
return value;
}
static irqreturn_t sgiwd93_intr(int irq, void *dev_id)
{
struct Scsi_Host * host = (struct Scsi_Host *) dev_id;
unsigned long flags;
spin_lock_irqsave(host->host_lock, flags);
wd33c93_intr(host);
spin_unlock_irqrestore(host->host_lock, flags);
return IRQ_HANDLED;
}
static inline
void fill_hpc_entries(struct hpc_chunk *hcp, struct scsi_cmnd *cmd, int datainp)
{
unsigned long len = cmd->SCp.this_residual;
void *addr = cmd->SCp.ptr;
dma_addr_t physaddr;
unsigned long count;
physaddr = dma_map_single(NULL, addr, len, cmd->sc_data_direction);
cmd->SCp.dma_handle = physaddr;
while (len) {
/*
* even cntinfo could be up to 16383, without
* magic only 8192 works correctly
*/
count = len > 8192 ? 8192 : len;
hcp->desc.pbuf = physaddr;
hcp->desc.cntinfo = count;
hcp++;
len -= count;
physaddr += count;
}
/*
* To make sure, if we trip an HPC bug, that we transfer every single
* byte, we tag on an extra zero length dma descriptor at the end of
* the chain.
*/
hcp->desc.pbuf = 0;
hcp->desc.cntinfo = HPCDMA_EOX;
}
static int dma_setup(struct scsi_cmnd *cmd, int datainp)
{
struct ip22_hostdata *hdata = HDATA(cmd->device->host);
struct hpc3_scsiregs *hregs =
(struct hpc3_scsiregs *) cmd->device->host->base;
struct hpc_chunk *hcp = (struct hpc_chunk *) hdata->hd.cpu;
DPRINTK("dma_setup: datainp<%d> hcp<%p> ", datainp, hcp);
hdata->wh.dma_dir = datainp;
/*
* wd33c93 shouldn't pass us bogus dma_setups, but it does:-( The
* other wd33c93 drivers deal with it the same way (which isn't that
* obvious). IMHO a better fix would be, not to do these dma setups
* in the first place.
*/
if (cmd->SCp.ptr == NULL || cmd->SCp.this_residual == 0)
return 1;
fill_hpc_entries(hcp, cmd, datainp);
DPRINTK(" HPCGO\n");
/* Start up the HPC. */
hregs->ndptr = hdata->hd.dma;
if (datainp)
hregs->ctrl = HPC3_SCTRL_ACTIVE;
else
hregs->ctrl = HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR;
return 0;
}
static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
int status)
{
struct ip22_hostdata *hdata = HDATA(instance);
struct hpc3_scsiregs *hregs;
if (!SCpnt)
return;
hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;
DPRINTK("dma_stop: status<%d> ", status);
/* First stop the HPC and flush it's FIFO. */
if (hdata->wh.dma_dir) {
hregs->ctrl |= HPC3_SCTRL_FLUSH;
while (hregs->ctrl & HPC3_SCTRL_ACTIVE)
barrier();
}
hregs->ctrl = 0;
dma_unmap_single(NULL, SCpnt->SCp.dma_handle, SCpnt->SCp.this_residual,
SCpnt->sc_data_direction);
DPRINTK("\n");
}
void sgiwd93_reset(unsigned long base)
{
struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) base;
hregs->ctrl = HPC3_SCTRL_CRESET;
udelay(50);
hregs->ctrl = 0;
}
static inline void init_hpc_chain(struct hpc_data *hd)
{
struct hpc_chunk *hcp = (struct hpc_chunk *) hd->cpu;
struct hpc_chunk *dma = (struct hpc_chunk *) hd->dma;
unsigned long start, end;
start = (unsigned long) hcp;
end = start + PAGE_SIZE;
while (start < end) {
hcp->desc.pnext = (u32) (dma + 1);
hcp->desc.cntinfo = HPCDMA_EOX;
hcp++; dma++;
start += sizeof(struct hpc_chunk);
};
hcp--;
hcp->desc.pnext = hd->dma;
}
static struct Scsi_Host * __init sgiwd93_setup_scsi(
struct scsi_host_template *SGIblows, int unit, int irq,
struct hpc3_scsiregs *hregs, unsigned char *wdregs)
{
struct ip22_hostdata *hdata;
struct Scsi_Host *host;
wd33c93_regs regs;
host = scsi_register(SGIblows, sizeof(struct ip22_hostdata));
if (!host)
return NULL;
host->base = (unsigned long) hregs;
host->irq = irq;
hdata = HDATA(host);
hdata->hd.cpu = dma_alloc_coherent(NULL, PAGE_SIZE, &hdata->hd.dma,
GFP_KERNEL);
if (!hdata->hd.cpu) {
printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
"host %d buffer.\n", unit);
goto out_unregister;
}
init_hpc_chain(&hdata->hd);
regs.SASR = wdregs + 3;
regs.SCMD = wdregs + 7;
wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_MHZ(20));
if (hdata->wh.no_sync == 0xff)
hdata->wh.no_sync = 0;
if (request_irq(irq, sgiwd93_intr, 0, "SGI WD93", (void *) host)) {
printk(KERN_WARNING "sgiwd93: Could not register irq %d "
"for host %d.\n", irq, unit);
goto out_free;
}
return host;
out_free:
dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
wd33c93_release();
out_unregister:
scsi_unregister(host);
return NULL;
}
static int __init sgiwd93_detect(struct scsi_host_template *SGIblows)
{
int found = 0;
SGIblows->proc_name = "SGIWD93";
sgiwd93_host = sgiwd93_setup_scsi(SGIblows, 0, SGI_WD93_0_IRQ,
&hpc3c0->scsi_chan0,
(unsigned char *)hpc3c0->scsi0_ext);
if (sgiwd93_host)
found++;
/* Set up second controller on the Indigo2 */
if (ip22_is_fullhouse()) {
sgiwd93_host1 = sgiwd93_setup_scsi(SGIblows, 1, SGI_WD93_1_IRQ,
&hpc3c0->scsi_chan1,
(unsigned char *)hpc3c0->scsi1_ext);
if (sgiwd93_host1)
found++;
}
return found;
}
static int sgiwd93_release(struct Scsi_Host *instance)
{
struct ip22_hostdata *hdata = HDATA(instance);
int irq = 0;
if (sgiwd93_host && sgiwd93_host == instance)
irq = SGI_WD93_0_IRQ;
else if (sgiwd93_host1 && sgiwd93_host1 == instance)
irq = SGI_WD93_1_IRQ;
free_irq(irq, sgiwd93_intr);
dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
wd33c93_release();
return 1;
}
static int sgiwd93_bus_reset(struct scsi_cmnd *cmd)
{
/* FIXME perform bus-specific reset */
/* FIXME 2: kill this function, and let midlayer fallback
to the same result, calling wd33c93_host_reset() */
spin_lock_irq(cmd->device->host->host_lock);
wd33c93_host_reset(cmd);
spin_unlock_irq(cmd->device->host->host_lock);
return SUCCESS;
}
/*
* Kludge alert - the SCSI code calls the abort and reset method with int
* arguments not with pointers. So this is going to blow up beautyfully
* on 64-bit systems with memory outside the compat address spaces.
*/
static struct scsi_host_template driver_template = {
.proc_name = "SGIWD93",
.name = "SGI WD93",
.detect = sgiwd93_detect,
.release = sgiwd93_release,
.queuecommand = wd33c93_queuecommand,
.eh_abort_handler = wd33c93_abort,
.eh_bus_reset_handler = sgiwd93_bus_reset,
.eh_host_reset_handler = wd33c93_host_reset,
.can_queue = 16,
.this_id = 7,
.sg_tablesize = SG_ALL,
.cmd_per_lun = 8,
.use_clustering = DISABLE_CLUSTERING,
};
#include "scsi_module.c"