Hello.

Alan Cox wrote:

        Just one version of Linux ago
        The PLL code broke - oh no!
        But set the right mode
        And fix up the code
        Makes the PLL timing sync go

/me applauds :-)

Closes-bug: #8791
Signed-off-by: Alan Cox <[EMAIL PROTECTED]>

Acked-by: Sergei Shtylyov <[EMAIL PROTECTED]>

However, I found it strange that HPT374 against which was that bug report works with 66 MHz DPLL clock -- while I've recently forbidden that clock in the IDE driver because it was causing DMA timeouts.

diff -u --new-file --recursive --exclude-from /usr/src/exclude 
linux.vanilla-2.6.23rc1/drivers/ata/pata_hpt37x.c 
linux-2.6.23rc1/drivers/ata/pata_hpt37x.c
--- linux.vanilla-2.6.23rc1/drivers/ata/pata_hpt37x.c   2007-07-23 
12:56:11.000000000 +0100
+++ linux-2.6.23rc1/drivers/ata/pata_hpt37x.c   2007-07-23 14:44:39.000000000 
+0100
@@ -26,7 +26,7 @@
 #include <linux/libata.h>
#define DRV_NAME "pata_hpt37x"
-#define DRV_VERSION    "0.6.6"
+#define DRV_VERSION    "0.6.7"
struct hpt_clock {
        u8      xfer_speed;
@@ -1103,17 +1103,17 @@
/* Select the DPLL clock. */
                pci_write_config_byte(dev, 0x5b, 0x21);
-               pci_write_config_dword(dev, 0x5C, (f_high << 16) | f_low);
+               pci_write_config_dword(dev, 0x5C, (f_high << 16) | f_low | 
0x100);

   Heh, was quite a silly mistake. :-)

>            for(adjust = 0; adjust < 8; adjust++) {
>                    if (hpt37x_calibrate_dpll(dev))
>                            break;
>                    /* See if it'll settle at a fractionally different clock */
> -                  if ((adjust & 3) == 3) {
> -                          f_low --;
> -                          f_high ++;
> -                  }
> -                  pci_write_config_dword(dev, 0x5C, (f_high << 16) | f_low);
> +                  if (adjust & 1)
> +                          f_low -= adjust >> 1;
> +                  else
> +                          f_high += adjust >> 1;
> +                  pci_write_config_dword(dev, 0x5C, (f_high << 16) | f_low | 
0x100);

OK, I'm seeing that the "oldie but goodie" calibration algrithm has finally found its way to the libata driver too. :-)

MBR, Sergei
-
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