[PATCH] (pata-2.6 fix queue) sl82c105: DMA support code cleanup
Sergei Shtylyov
sshtylyov at ru.mvista.com
Wed Feb 14 08:43:25 EST 2007
Fold the now equivalent code in the ide_dma_check() method into a mere call to
ide_use_dma(). Make config_for_dma() return non-zero if DMA mode has been set
and call it from the ide_dma_check() method instead of ide_dma_on().
Also, defer writing the DMA timings to the chip registers until DMA is actually
turned on (and do not enable IORDY for DMA). Remove unnecessary code from the
init_hwif() method, improve its looks overall, and also rename the driver's
ide_dma_check() and dma_start() methods.
Signed-off-by: Sergei Shtylyov <sshtylyov at ru.mvista.com>
---
The patch has been actually tested at last. :-)
Note that now this driver can be joined to the ide-use-fast-pio patch.
drivers/ide/pci/sl82c105.c | 114 +++++++++++++++++----------------------------
1 files changed, 45 insertions(+), 69 deletions(-)
Index: linux-2.6/drivers/ide/pci/sl82c105.c
===================================================================
--- linux-2.6.orig/drivers/ide/pci/sl82c105.c
+++ linux-2.6/drivers/ide/pci/sl82c105.c
@@ -11,6 +11,8 @@
* Merge in Russell's HW workarounds, fix various problems
* with the timing registers setup.
* -- Benjamin Herrenschmidt (01/11/03) benh at kernel.crashing.org
+ *
+ * Copyright (C) 2006-2007 MontaVista Software, Inc. <source at mvista.com>
*/
#include <linux/types.h>
@@ -114,59 +116,32 @@ static void config_for_pio(ide_drive_t *
}
/*
- * Configure the drive and the chipset for DMA
+ * Configure the drive for DMA.
+ * We'll program the chipset only when DMA is actually turned on.
*/
static int config_for_dma (ide_drive_t *drive)
{
- ide_hwif_t *hwif = HWIF(drive);
- struct pci_dev *dev = hwif->pci_dev;
- unsigned int reg;
-
DBG(("config_for_dma(drive:%s)\n", drive->name));
- reg = (hwif->channel ? 0x4c : 0x44) + (drive->select.b.unit ? 4 : 0);
-
if (ide_config_drive_speed(drive, XFER_MW_DMA_2) != 0)
- return 1;
+ return 0;
- pci_write_config_word(dev, reg, 0x0240);
-
- return 0;
+ return ide_dma_enable(drive);
}
/*
- * Check to see if the drive and
- * chipset is capable of DMA mode
+ * Check to see if the drive and chipset are capable of DMA mode.
*/
-
-static int sl82c105_check_drive (ide_drive_t *drive)
+static int sl82c105_ide_dma_check (ide_drive_t *drive)
{
ide_hwif_t *hwif = HWIF(drive);
+ struct hd_driveid *id = drive->id;
- DBG(("sl82c105_check_drive(drive:%s)\n", drive->name));
-
- do {
- struct hd_driveid *id = drive->id;
-
- if (!drive->autodma)
- break;
-
- if (!id || !(id->capability & 1))
- break;
-
- /* Consult the list of known "bad" drives */
- if (__ide_dma_bad_drive(drive))
- break;
+ DBG(("sl82c105_ide_dma_check(drive:%s)\n", drive->name));
- if (id->field_valid & 2) {
- if ((id->dma_mword & hwif->mwdma_mask) ||
- (id->dma_1word & hwif->swdma_mask))
- return hwif->ide_dma_on(drive);
- }
-
- if (__ide_dma_good_drive(drive) && id->eide_dma_time < 150)
- return hwif->ide_dma_on(drive);
- } while (0);
+ if (drive->autodma && (id->capability & 1) &&
+ ide_use_dma(drive) && config_for_dma(drive))
+ return hwif->ide_dma_on(drive);
return hwif->ide_dma_off_quietly(drive);
}
@@ -235,7 +210,7 @@ static int sl82c105_ide_dma_lost_irq(ide
* The generic IDE core will have disabled the BMEN bit before this
* function is called.
*/
-static void sl82c105_ide_dma_start(ide_drive_t *drive)
+static void sl82c105_dma_start(ide_drive_t *drive)
{
ide_hwif_t *hwif = HWIF(drive);
struct pci_dev *dev = hwif->pci_dev;
@@ -257,12 +232,18 @@ static int sl82c105_ide_dma_timeout(ide_
static int sl82c105_ide_dma_on (ide_drive_t *drive)
{
+ struct pci_dev *dev = HWIF(drive)->pci_dev;
+ int rc, reg = 0x44 + drive->dn * 4;
+
DBG(("sl82c105_ide_dma_on(drive:%s)\n", drive->name));
- if (config_for_dma(drive))
- return 1;
- printk(KERN_INFO "%s: DMA enabled\n", drive->name);
- return __ide_dma_on(drive);
+ rc = __ide_dma_on(drive);
+ if (rc == 0) {
+ pci_write_config_word(dev, reg, 0x0200);
+
+ printk(KERN_INFO "%s: DMA enabled\n", drive->name);
+ }
+ return rc;
}
static int sl82c105_ide_dma_off_quietly (ide_drive_t *drive)
@@ -396,7 +377,7 @@ static unsigned int __devinit init_chips
}
/*
- * Initialise the chip
+ * Initialise IDE channel
*/
static void __devinit init_hwif_sl82c105(ide_hwif_t *hwif)
{
@@ -418,11 +399,6 @@ static void __devinit init_hwif_sl82c105
hwif->drives[1].pio_speed = XFER_PIO_0;
hwif->drives[1].autotune = 1;
- hwif->atapi_dma = 0;
- hwif->mwdma_mask = 0;
- hwif->swdma_mask = 0;
- hwif->autodma = 0;
-
if (!hwif->dma_base)
return;
@@ -432,27 +408,27 @@ static void __devinit init_hwif_sl82c105
* Never ever EVER under any circumstances enable
* DMA when the bridge is this old.
*/
- printk(" %s: Winbond 553 bridge revision %d, BM-DMA disabled\n",
- hwif->name, rev);
- } else {
- hwif->atapi_dma = 1;
- hwif->mwdma_mask = 0x04;
-
- hwif->ide_dma_check = &sl82c105_check_drive;
- hwif->ide_dma_on = &sl82c105_ide_dma_on;
- hwif->ide_dma_off_quietly = &sl82c105_ide_dma_off_quietly;
- hwif->ide_dma_lostirq = &sl82c105_ide_dma_lost_irq;
- hwif->dma_start = &sl82c105_ide_dma_start;
- hwif->ide_dma_timeout = &sl82c105_ide_dma_timeout;
-
- if (!noautodma)
- hwif->autodma = 1;
- hwif->drives[0].autodma = hwif->autodma;
- hwif->drives[1].autodma = hwif->autodma;
-
- if (hwif->mate)
- hwif->serialized = hwif->mate->serialized = 1;
+ printk(" %s: Winbond W83C553 bridge revision %d, "
+ "BM-DMA disabled\n", hwif->name, rev);
+ return;
}
+
+ hwif->atapi_dma = 1;
+ hwif->mwdma_mask = 0x04;
+
+ hwif->ide_dma_check = &sl82c105_ide_dma_check;
+ hwif->ide_dma_on = &sl82c105_ide_dma_on;
+ hwif->ide_dma_off_quietly = &sl82c105_ide_dma_off_quietly;
+ hwif->ide_dma_lostirq = &sl82c105_ide_dma_lost_irq;
+ hwif->dma_start = &sl82c105_dma_start;
+ hwif->ide_dma_timeout = &sl82c105_ide_dma_timeout;
+
+ if (!noautodma)
+ hwif->autodma = 1;
+ hwif->drives[0].autodma = hwif->drives[1].autodma = hwif->autodma;
+
+ if (hwif->mate)
+ hwif->serialized = hwif->mate->serialized = 1;
}
static ide_pci_device_t sl82c105_chipset __devinitdata = {
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