Re: [RFC]hpt366/ide-probe reset drive on probe error.

[Sergei Shtylyov <sshtylyov@xxxxxxxxxxxxx>]

Bartlomiej Zolnierkiewicz wrote:

> > > > diff --git a/drivers/ide/hpt366.c b/drivers/ide/hpt366.c
> > > > index 3377766..ba4b802 100644
> > > > --- a/drivers/ide/hpt366.c
> > > > +++ b/drivers/ide/hpt366.c
> > > > @@ -1280,6 +1280,31 @@ static u8 hpt3xx_cable_detect(ide_hwif_t *hwif)
> > > > 	return (scr1 & ata66) ? ATA_CBL_PATA40 : ATA_CBL_PATA80;
> > > > }
> > > >
> > > > +/** routine to reset disk
> > > > + *
> > > > + * Since SUN Cobalt is attempting to do this operation, I should disclose
> > > > + * this has been a long time ago Thu Jul 27 16:40:57 2000 was the patch date
> > > > + * HOTSWAP ATA Infrastructure.
> > > > + */
> > > > +
> > > > +static void hpt3xx_reset (ide_drive_t *drive)
> > > > +{
> > > > +	ide_hwif_t *hwif = drive->hwif;
> > > > +	struct pci_dev *dev = to_pci_dev(hwif->dev);
> > > > +	unsigned long high_16;
> > > > +	u8 reset;
> > > > +	u8 reg59h = 0;
> > > > +
> > > > +	printk(KERN_INFO "%s reset drive channel %d\n", __func__, hwif->channel);
> > > > +	high_16 = pci_resource_start(dev, 4);
> > > > +
> > > > +	reset = hwif->channel ? 0x80 : 0x40;
> > > > +
> > > > +	pci_read_config_byte(dev, 0x59, &reg59h);
> > > > +	pci_write_config_byte(dev, 0x59, reg59h|reset);
> > > > +	pci_write_config_byte(dev, 0x59, reg59h);
> > > > +}
> > > > +
> > > > static void __devinit init_hwif_hpt366(ide_hwif_t *hwif)
> > > > {
> > > > 	struct hpt_info *info	= hpt3xx_get_info(hwif->dev);
> > > > @@ -1406,6 +1431,7 @@ static const struct ide_port_ops hpt3xx_port_ops = {
> > > > 	.set_pio_mode		= hpt3xx_set_pio_mode,
> > > > 	.set_dma_mode		= hpt3xx_set_mode,
> > > > 	.quirkproc		= hpt3xx_quirkproc,
> > > > +	.resetproc		= hpt3xx_reset,
> > > > 	.maskproc		= hpt3xx_maskproc,
> > > > 	.mdma_filter		= hpt3xx_mdma_filter,
> > > > 	.udma_filter		= hpt3xx_udma_filter,
> > > > diff --git a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c
> > > > index 7f264ed..09295b4 100644
> > > > --- a/drivers/ide/ide-probe.c
> > > > +++ b/drivers/ide/ide-probe.c
> > > > @@ -367,6 +367,7 @@ static int do_probe (ide_drive_t *drive, u8 cmd)
> > > > {
> > > > 	ide_hwif_t *hwif = drive->hwif;
> > > > 	const struct ide_tp_ops *tp_ops = hwif->tp_ops;
> > > > +	const struct ide_port_ops *port_ops = hwif->port_ops;
> > > > 	u16 *id = drive->id;
> > > > 	int rc;
> > > > 	u8 present = !!(drive->dev_flags & IDE_DFLAG_PRESENT), stat;
> > > > @@ -427,9 +428,20 @@ static int do_probe (ide_drive_t *drive, u8 cmd)
> > > > 		/* ensure drive IRQ is clear */
> > > > 		stat = tp_ops->read_status(hwif);
> > > >
> > > > -		if (rc == 1)
> > > > +		if (rc == 1) {
> > > > 			printk(KERN_ERR "%s: no response (status = 0x%02x)\n",
> > > > 					drive->name, stat);
> > > > +
> > > > +			if (port_ops->resetproc) {
> > > > +				port_ops->resetproc(drive);
> > > > +				msleep(50);
> > > > +			}
> > > > +			tp_ops->dev_select(drive);
> > > > +			msleep(50);
> > > > +			tp_ops->exec_command(hwif, ATA_CMD_DEV_RESET);
> > > > +			(void)ide_busy_sleep(hwif, WAIT_WORSTCASE, 0);
> > > > +			rc = ide_dev_read_id(drive, cmd, id);
> > > > +		}
> > > > 	} else {
> > > > 		/* not present or maybe ATAPI */
> > > > 		rc = 3;
> > >
> > > Since the current code in ide-probe.c looks like this:
> > >
> > > 		stat = tp_ops->read_status(hwif);
> > >
> > > 		if (stat == (ATA_BUSY | ATA_DRDY))
> > > 			return 4;
> > >
> > > 		if (rc == 1 && cmd == ATA_CMD_ID_ATAPI) {
> > > 			printk(KERN_ERR "%s: no response (status = 0x%02x), "
> > > 					"resetting drive\n", drive->name, stat);
> > > 			msleep(50);
> > > 			tp_ops->dev_select(drive);
> > > 			msleep(50);
> > > 			tp_ops->exec_command(hwif, ATA_CMD_DEV_RESET);
> > > 			(void)ide_busy_sleep(hwif, WAIT_WORSTCASE, 0);
> > > 			rc = ide_dev_read_id(drive, cmd, id);
> > > 		}
> > >
> > > 		/* ensure drive IRQ is clear */
> > > 		stat = tp_ops->read_status(hwif);
> > >
> > > 		if (rc == 1)
> > > 			printk(KERN_ERR "%s: no response (status = 0x%02x)\n",
> > > 					drive->name, stat);
> > >
> > > I would really prefer fixing ATAPI case while we are at it
> > > (+ this would also get rid of code duplication).
> > >
> > > IOW:
> > >
> > > - in patch #1 we would add ->resetproc call
> > >
> > > - in patch #2 we would remove 'cmd == ATA_CMD_ID_ATAPI' check
> >
> > [ looking a bit closer at the code in ide-probe.c ]
> >
> > - in patch #2 we would move the ATAPI check to cover device selection/reset
> >  inside 'if ()' block

> Sigh, this is even more complicated...

> We should defer ->resetproc call until both drives are probed and do the
> port reset after probing both drives given that:

   We should just reset the port (and call resetproc() as a part of that). 
The resetproc() change should not be needed.

> - we didn't detect any devices

> and 

> - for one of devices do_probe() returned '1' (== "no response")

> Also it would greatly help to clean/fix return values of do_probe()
> and probe_for_drive() before doing the real changes.

   Sounds like the plan. :-)

> Thanks,
> Bart

MBR, Sergei
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