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ide: remove stale comments from ide-dma.c (take 2)

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- ide-dma.c is not a separate module

- ide-dma.c is not PCI specific anymore

- DMA is enabled by default nowadays

- link for Intel Zappa BIOS is dead

etc.

v2:
* Some comments should be preserved. (Noticed by Mark Lord)

Cc: Mark Lord <liml@rtr.ca>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This commit is contained in:
Bartlomiej Zolnierkiewicz 2008-02-26 21:50:36 +01:00
parent 56467d17d2
commit 204f47c5a5
1 changed files with 4 additions and 48 deletions
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52
drivers/ide/ide-dma.c
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@ -1,9 +1,13 @@
/*
* IDE DMA support (including IDE PCI BM-DMA).
*
* Copyright (C) 1995-1998 Mark Lord
* Copyright (C) 1999-2000 Andre Hedrick <andre@linux-ide.org>
* Copyright (C) 2004, 2007 Bartlomiej Zolnierkiewicz
*
* May be copied or modified under the terms of the GNU General Public License
*
* DMA is supported for all IDE devices (disk drives, cdroms, tapes, floppies).
*/
/*
@ -11,49 +15,6 @@
*/
/*
* This module provides support for the bus-master IDE DMA functions
* of various PCI chipsets, including the Intel PIIX (i82371FB for
* the 430 FX chipset), the PIIX3 (i82371SB for the 430 HX/VX and
* 440 chipsets), and the PIIX4 (i82371AB for the 430 TX chipset)
* ("PIIX" stands for "PCI ISA IDE Xcellerator").
*
* Pretty much the same code works for other IDE PCI bus-mastering chipsets.
*
* DMA is supported for all IDE devices (disk drives, cdroms, tapes, floppies).
*
* By default, DMA support is prepared for use, but is currently enabled only
* for drives which already have DMA enabled (UltraDMA or mode 2 multi/single),
* or which are recognized as "good" (see table below). Drives with only mode0
* or mode1 (multi/single) DMA should also work with this chipset/driver
* (eg. MC2112A) but are not enabled by default.
*
* Use "hdparm -i" to view modes supported by a given drive.
*
* The hdparm-3.5 (or later) utility can be used for manually enabling/disabling
* DMA support, but must be (re-)compiled against this kernel version or later.
*
* To enable DMA, use "hdparm -d1 /dev/hd?" on a per-drive basis after booting.
* If problems arise, ide.c will disable DMA operation after a few retries.
* This error recovery mechanism works and has been extremely well exercised.
*
* IDE drives, depending on their vintage, may support several different modes
* of DMA operation. The boot-time modes are indicated with a "*" in
* the "hdparm -i" listing, and can be changed with *knowledgeable* use of
* the "hdparm -X" feature. There is seldom a need to do this, as drives
* normally power-up with their "best" PIO/DMA modes enabled.
*
* Testing has been done with a rather extensive number of drives,
* with Quantum & Western Digital models generally outperforming the pack,
* and Fujitsu & Conner (and some Seagate which are really Conner) drives
* showing more lackluster throughput.
*
* Keep an eye on /var/adm/messages for "DMA disabled" messages.
*
* Some people have reported trouble with Intel Zappa motherboards.
* This can be fixed by upgrading the AMI BIOS to version 1.00.04.BS0,
* available from ftp://ftp.intel.com/pub/bios/10004bs0.exe
* (thanks to Glen Morrell <glen@spin.Stanford.edu> for researching this).
*
* Thanks to "Christopher J. Reimer" <reimer@doe.carleton.ca> for
* fixing the problem with the BIOS on some Acer motherboards.
*
@ -65,11 +26,6 @@
*
* Most importantly, thanks to Robert Bringman <rob@mars.trion.com>
* for supplying a Promise UDMA board & WD UDMA drive for this work!
*
* And, yes, Intel Zappa boards really *do* use both PIIX IDE ports.
*
* ATA-66/100 and recovery functions, I forgot the rest......
*
*/
#include <linux/module.h>