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linux-2.6/drivers/ata/pata_sl82c105.c
Tejun Heo a1efdaba2d libata: make reset related methods proper port operations
Currently reset methods are not specified directly in the
ata_port_operations table.  If a LLD wants to use custom reset
methods, it should construct and use a error_handler which uses those
reset methods.  It's done this way for two reasons.

First, the ops table already contained too many methods and adding
four more of them would noticeably increase the amount of necessary
boilerplate code all over low level drivers.

Second, as ->error_handler uses those reset methods, it can get
confusing.  ie. By overriding ->error_handler, those reset ops can be
made useless making layering a bit hazy.

Now that ops table uses inheritance, the first problem doesn't exist
anymore.  The second isn't completely solved but is relieved by
providing default values - most drivers can just override what it has
implemented and don't have to concern itself about higher level
callbacks.  In fact, there currently is no driver which actually
modifies error handling behavior.  Drivers which override
->error_handler just wraps the standard error handler only to prepare
the controller for EH.  I don't think making ops layering strict has
any noticeable benefit.

This patch makes ->prereset, ->softreset, ->hardreset, ->postreset and
their PMP counterparts propoer ops.  Default ops are provided in the
base ops tables and drivers are converted to override individual reset
methods instead of creating custom error_handler.

* ata_std_error_handler() doesn't use sata_std_hardreset() if SCRs
  aren't accessible.  sata_promise doesn't need to use separate
  error_handlers for PATA and SATA anymore.

* softreset is broken for sata_inic162x and sata_sx4.  As libata now
  always prefers hardreset, this doesn't really matter but the ops are
  forced to NULL using ATA_OP_NULL for documentation purpose.

* pata_hpt374 needs to use different prereset for the first and second
  PCI functions.  This used to be done by branching from
  hpt374_error_handler().  The proper way to do this is to use
  separate ops and port_info tables for each function.  Converted.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:18 -04:00

354 lines
8.8 KiB
C

/*
* pata_sl82c105.c - SL82C105 PATA for new ATA layer
* (C) 2005 Red Hat Inc
* Alan Cox <alan@redhat.com>
*
* Based in part on linux/drivers/ide/pci/sl82c105.c
* SL82C105/Winbond 553 IDE driver
*
* and in part on the documentation and errata sheet
*
*
* Note: The controller like many controllers has shared timings for
* PIO and DMA. We thus flip to the DMA timings in dma_start and flip back
* in the dma_stop function. Thus we actually don't need a set_dmamode
* method as the PIO method is always called and will set the right PIO
* timing parameters.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#define DRV_NAME "pata_sl82c105"
#define DRV_VERSION "0.3.3"
enum {
/*
* SL82C105 PCI config register 0x40 bits.
*/
CTRL_IDE_IRQB = (1 << 30),
CTRL_IDE_IRQA = (1 << 28),
CTRL_LEGIRQ = (1 << 11),
CTRL_P1F16 = (1 << 5),
CTRL_P1EN = (1 << 4),
CTRL_P0F16 = (1 << 1),
CTRL_P0EN = (1 << 0)
};
/**
* sl82c105_pre_reset - probe begin
* @link: ATA link
* @deadline: deadline jiffies for the operation
*
* Set up cable type and use generic probe init
*/
static int sl82c105_pre_reset(struct ata_link *link, unsigned long deadline)
{
static const struct pci_bits sl82c105_enable_bits[] = {
{ 0x40, 1, 0x01, 0x01 },
{ 0x40, 1, 0x10, 0x10 }
};
struct ata_port *ap = link->ap;
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
if (ap->port_no && !pci_test_config_bits(pdev, &sl82c105_enable_bits[ap->port_no]))
return -ENOENT;
return ata_std_prereset(link, deadline);
}
/**
* sl82c105_configure_piomode - set chip PIO timing
* @ap: ATA interface
* @adev: ATA device
* @pio: PIO mode
*
* Called to do the PIO mode setup. Our timing registers are shared
* so a configure_dmamode call will undo any work we do here and vice
* versa
*/
static void sl82c105_configure_piomode(struct ata_port *ap, struct ata_device *adev, int pio)
{
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
static u16 pio_timing[5] = {
0x50D, 0x407, 0x304, 0x242, 0x240
};
u16 dummy;
int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);
pci_write_config_word(pdev, timing, pio_timing[pio]);
/* Can we lose this oddity of the old driver */
pci_read_config_word(pdev, timing, &dummy);
}
/**
* sl82c105_set_piomode - set initial PIO mode data
* @ap: ATA interface
* @adev: ATA device
*
* Called to do the PIO mode setup. Our timing registers are shared
* but we want to set the PIO timing by default.
*/
static void sl82c105_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
sl82c105_configure_piomode(ap, adev, adev->pio_mode - XFER_PIO_0);
}
/**
* sl82c105_configure_dmamode - set DMA mode in chip
* @ap: ATA interface
* @adev: ATA device
*
* Load DMA cycle times into the chip ready for a DMA transfer
* to occur.
*/
static void sl82c105_configure_dmamode(struct ata_port *ap, struct ata_device *adev)
{
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
static u16 dma_timing[3] = {
0x707, 0x201, 0x200
};
u16 dummy;
int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno);
int dma = adev->dma_mode - XFER_MW_DMA_0;
pci_write_config_word(pdev, timing, dma_timing[dma]);
/* Can we lose this oddity of the old driver */
pci_read_config_word(pdev, timing, &dummy);
}
/**
* sl82c105_reset_engine - Reset the DMA engine
* @ap: ATA interface
*
* The sl82c105 has some serious problems with the DMA engine
* when transfers don't run as expected or ATAPI is used. The
* recommended fix is to reset the engine each use using a chip
* test register.
*/
static void sl82c105_reset_engine(struct ata_port *ap)
{
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
u16 val;
pci_read_config_word(pdev, 0x7E, &val);
pci_write_config_word(pdev, 0x7E, val | 4);
pci_write_config_word(pdev, 0x7E, val & ~4);
}
/**
* sl82c105_bmdma_start - DMA engine begin
* @qc: ATA command
*
* Reset the DMA engine each use as recommended by the errata
* document.
*
* FIXME: if we switch clock at BMDMA start/end we might get better
* PIO performance on DMA capable devices.
*/
static void sl82c105_bmdma_start(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
udelay(100);
sl82c105_reset_engine(ap);
udelay(100);
/* Set the clocks for DMA */
sl82c105_configure_dmamode(ap, qc->dev);
/* Activate DMA */
ata_bmdma_start(qc);
}
/**
* sl82c105_bmdma_end - DMA engine stop
* @qc: ATA command
*
* Reset the DMA engine each use as recommended by the errata
* document.
*
* This function is also called to turn off DMA when a timeout occurs
* during DMA operation. In both cases we need to reset the engine,
* so no actual eng_timeout handler is required.
*
* We assume bmdma_stop is always called if bmdma_start as called. If
* not then we may need to wrap qc_issue.
*/
static void sl82c105_bmdma_stop(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
ata_bmdma_stop(qc);
sl82c105_reset_engine(ap);
udelay(100);
/* This will redo the initial setup of the DMA device to matching
PIO timings */
sl82c105_set_piomode(ap, qc->dev);
}
/**
* sl82c105_qc_defer - implement serialization
* @qc: command
*
* We must issue one command per host not per channel because
* of the reset bug.
*
* Q: is the scsi host lock sufficient ?
*/
static int sl82c105_qc_defer(struct ata_queued_cmd *qc)
{
struct ata_host *host = qc->ap->host;
struct ata_port *alt = host->ports[1 ^ qc->ap->port_no];
int rc;
/* First apply the usual rules */
rc = ata_std_qc_defer(qc);
if (rc != 0)
return rc;
/* Now apply serialization rules. Only allow a command if the
other channel state machine is idle */
if (alt && alt->qc_active)
return ATA_DEFER_PORT;
return 0;
}
static struct scsi_host_template sl82c105_sht = {
ATA_BMDMA_SHT(DRV_NAME),
};
static struct ata_port_operations sl82c105_port_ops = {
.inherits = &ata_bmdma_port_ops,
.qc_defer = sl82c105_qc_defer,
.bmdma_start = sl82c105_bmdma_start,
.bmdma_stop = sl82c105_bmdma_stop,
.cable_detect = ata_cable_40wire,
.set_piomode = sl82c105_set_piomode,
.prereset = sl82c105_pre_reset,
};
/**
* sl82c105_bridge_revision - find bridge version
* @pdev: PCI device for the ATA function
*
* Locates the PCI bridge associated with the ATA function and
* providing it is a Winbond 553 reports the revision. If it cannot
* find a revision or the right device it returns -1
*/
static int sl82c105_bridge_revision(struct pci_dev *pdev)
{
struct pci_dev *bridge;
/*
* The bridge should be part of the same device, but function 0.
*/
bridge = pci_get_slot(pdev->bus,
PCI_DEVFN(PCI_SLOT(pdev->devfn), 0));
if (!bridge)
return -1;
/*
* Make sure it is a Winbond 553 and is an ISA bridge.
*/
if (bridge->vendor != PCI_VENDOR_ID_WINBOND ||
bridge->device != PCI_DEVICE_ID_WINBOND_83C553 ||
bridge->class >> 8 != PCI_CLASS_BRIDGE_ISA) {
pci_dev_put(bridge);
return -1;
}
/*
* We need to find function 0's revision, not function 1
*/
pci_dev_put(bridge);
return bridge->revision;
}
static int sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id)
{
static const struct ata_port_info info_dma = {
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = 0x1f,
.mwdma_mask = 0x07,
.port_ops = &sl82c105_port_ops
};
static const struct ata_port_info info_early = {
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = 0x1f,
.port_ops = &sl82c105_port_ops
};
/* for now use only the first port */
const struct ata_port_info *ppi[] = { &info_early,
NULL };
u32 val;
int rev;
int rc;
rc = pcim_enable_device(dev);
if (rc)
return rc;
rev = sl82c105_bridge_revision(dev);
if (rev == -1)
dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Unable to find bridge, disabling DMA.\n");
else if (rev <= 5)
dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Early bridge revision, no DMA available.\n");
else
ppi[0] = &info_dma;
pci_read_config_dword(dev, 0x40, &val);
val |= CTRL_P0EN | CTRL_P0F16 | CTRL_P1F16;
pci_write_config_dword(dev, 0x40, val);
return ata_pci_init_one(dev, ppi, &sl82c105_sht, NULL);
}
static const struct pci_device_id sl82c105[] = {
{ PCI_VDEVICE(WINBOND, PCI_DEVICE_ID_WINBOND_82C105), },
{ },
};
static struct pci_driver sl82c105_pci_driver = {
.name = DRV_NAME,
.id_table = sl82c105,
.probe = sl82c105_init_one,
.remove = ata_pci_remove_one
};
static int __init sl82c105_init(void)
{
return pci_register_driver(&sl82c105_pci_driver);
}
static void __exit sl82c105_exit(void)
{
pci_unregister_driver(&sl82c105_pci_driver);
}
MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("low-level driver for Sl82c105");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, sl82c105);
MODULE_VERSION(DRV_VERSION);
module_init(sl82c105_init);
module_exit(sl82c105_exit);