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Message-Id: <200706032223.49063.bzolnier@gmail.com>
Date: Sun, 3 Jun 2007 22:23:48 +0200
From: Bartlomiej Zolnierkiewicz <bzolnier@...il.com>
To: linux-ide@...r.kernel.org
Cc: linux-kernel@...r.kernel.org, Alan Cox <alan@...rguk.ukuu.org.uk>
Subject: [PATCH 3/2] serverworks: always tune CSB6
[ yeah, this is a follow-up to yesterdays' patches thus #3/2 ]
Switch the driver to always program DMA/PIO timings and set device transfer
mode instead of trusting BIOS on CSB6 controllers (libata pata_serverworks.c
driver is also doing things this way and there were no problems reported so
far). While doing conversion I noticed that the old code had many issues:
* the code was assuming that hwif->dma_status is always valid
(which obviously isn't true if hwif->dma_base == NULL)
* value of "(ultra_timing >> (4*unit)) & ~(0xF0)" expression wasn't checked
to fit into udma_modes[5]
* code validating DMA timings didn't validate corresponding PIO timings
* extra CSB5 PIO register wasn't validated et all
* hwif->ide_dma_off_quietly() is always called before ide_set_dma() (which in
turn calls hwif->speedproc() method - svwks_tune_chipset() in this case)
so the code depending on DMA capable bit of DMA status to be set was never
executed (=> the code was never validating DMA timings despite actually
enabling DMA if the PIO timings were OK!)
* on resume driver dependend entirely on BIOS to restore timings and set
transfer mode on the device
While at it:
There is no need to read PIO/MWDMA timings now so don't do it.
Cc: Alan Cox <alan@...rguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@...il.com>
---
drivers/ide/pci/serverworks.c | 77 +-----------------------------------------
1 file changed, 2 insertions(+), 75 deletions(-)
Index: b/drivers/ide/pci/serverworks.c
===================================================================
--- a/drivers/ide/pci/serverworks.c
+++ b/drivers/ide/pci/serverworks.c
@@ -1,5 +1,5 @@
/*
- * linux/drivers/ide/pci/serverworks.c Version 0.11 Jun 2 2007
+ * linux/drivers/ide/pci/serverworks.c Version 0.20 Jun 3 2007
*
* Copyright (C) 1998-2000 Michel Aubry
* Copyright (C) 1998-2000 Andrzej Krzysztofowicz
@@ -151,84 +151,11 @@ static int svwks_tune_chipset (ide_drive
if(dev->device == PCI_DEVICE_ID_SERVERWORKS_OSB4 &&
drive->media == ide_disk && speed >= XFER_UDMA_0)
BUG();
-
- pci_read_config_byte(dev, drive_pci[drive->dn], &pio_timing);
- pci_read_config_byte(dev, drive_pci2[drive->dn], &dma_timing);
+
pci_read_config_byte(dev, (0x56|hwif->channel), &ultra_timing);
pci_read_config_word(dev, 0x4A, &csb5_pio);
pci_read_config_byte(dev, 0x54, &ultra_enable);
- /* If we are in RAID mode (eg AMI MegaIDE) then we can't it
- turns out trust the firmware configuration */
-
- if ((dev->class >> 8) != PCI_CLASS_STORAGE_IDE)
- goto oem_setup_failed;
-
- /* Per Specified Design by OEM, and ASIC Architect */
- if ((dev->device == PCI_DEVICE_ID_SERVERWORKS_CSB6IDE) ||
- (dev->device == PCI_DEVICE_ID_SERVERWORKS_CSB6IDE2)) {
- if (!drive->init_speed) {
- u8 dma_stat = inb(hwif->dma_status);
-
- if (((ultra_enable << (7-drive->dn) & 0x80) == 0x80) &&
- ((dma_stat & (1<<(5+unit))) == (1<<(5+unit)))) {
- drive->current_speed = drive->init_speed = XFER_UDMA_0 + udma_modes[(ultra_timing >> (4*unit)) & ~(0xF0)];
- return 0;
- } else if ((dma_timing) &&
- ((dma_stat&(1<<(5+unit)))==(1<<(5+unit)))) {
- u8 dmaspeed;
-
- switch (dma_timing & 0x77) {
- case 0x20:
- dmaspeed = XFER_MW_DMA_2;
- break;
- case 0x21:
- dmaspeed = XFER_MW_DMA_1;
- break;
- case 0x77:
- dmaspeed = XFER_MW_DMA_0;
- break;
- default:
- goto dma_pio;
- }
-
- drive->current_speed = drive->init_speed = dmaspeed;
- return 0;
- }
-dma_pio:
- if (pio_timing) {
- u8 piospeed;
-
- switch (pio_timing & 0x7f) {
- case 0x20:
- piospeed = XFER_PIO_4;
- break;
- case 0x22:
- piospeed = XFER_PIO_3;
- break;
- case 0x34:
- piospeed = XFER_PIO_2;
- break;
- case 0x47:
- piospeed = XFER_PIO_1;
- break;
- case 0x5d:
- piospeed = XFER_PIO_0;
- break;
- default:
- goto oem_setup_failed;
- }
-
- drive->current_speed = drive->init_speed = piospeed;
- return 0;
- }
- }
- }
-
-oem_setup_failed:
-
- pio_timing = 0;
- dma_timing = 0;
ultra_timing &= ~(0x0F << (4*unit));
ultra_enable &= ~(0x01 << drive->dn);
csb5_pio &= ~(0x0F << (4*drive->dn));
-
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