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

[Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>]

On Friday 08 May 2009 15:50:11 Bartlomiej Zolnierkiewicz wrote:
> 
> On Tuesday 05 May 2009 16:53:31 Karl Hiramoto wrote:
> > Hi,
> > 
> > Part of this patch (htp366.c) is commented in an #if 0   in older 
> > kernels.   2.6.11 for sure.
> > 
> > I have an ARM IXP4xx based board with CompactFlash slot that this patch 
> > fixes some issues for.    I think the case, is only with a warm boot, 
> > where the drive was busy before the board was reset.   There is  no 
> > BIOS, only the redboot loader which loads the kernel.
> > 
> > 
> > A few questions:
> > 
> > 1.  Would this be considerd to be brought into mainline?
> 
> When it comes to ide-probe.c changes: yes given that you split them on
> smaller patches.  hpt366.c change also seems to be correct on the first
> glance but I think that Sergei's opinion would be more suited here.
> 
> > 2.  How would you port something like this to using the SATA layer?
> > 
> > Would it go to the ata_port_operations.prereset,  softreset or hardreset?
> > 
> > --
> > Karl
> > 
> > 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