Commit f13c1526 authored by Sergei Shtylyov's avatar Sergei Shtylyov Committed by Linus Torvalds

[PATCH] HPT37x: read f_CNT saved by BIOS from port

The undocumented register BIOS uses for saving f_CNT seems to only be
mapped to I/O space while all the other HPT3xx regs are dual-mapped.  Looks
like another HighPoint's dirty trick.  With this patch, the deadly kernel
oops on the cards having the modern HighPoint BIOSes is now at last gone!
Signed-off-by: default avatarSergei Shtylyov <>
Cc: Bartlomiej Zolnierkiewicz <>
Cc: Alan Cox <>
Signed-off-by: default avatarAndrew Morton <>
Signed-off-by: default avatarLinus Torvalds <>
parent 26c068da
......@@ -1035,14 +1035,14 @@ static void __devinit hpt37x_clocking(ide_hwif_t *hwif)
* First try reading the register in which the HighPoint BIOS
* saves f_CNT value before reprogramming the DPLL from its
* default setting (which differs for the various chips).
* NOTE: This register is only accessible via I/O space.
* In case the signature check fails, we'll have to resort to
* reading the f_CNT register itself in hopes that nobody has
* touched the DPLL yet...
pci_read_config_dword(dev, 0x70, &temp);
temp = inl(pci_resource_start(dev, 4) + 0x90);
if ((temp & 0xFFFFF000) != 0xABCDE000) {
int i;
printk(KERN_WARNING "HPT37X: no clock data saved by BIOS\n");
/* Calculate the average value of f_CNT */
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