kernel-fxtec-pro1x/drivers/ata/pata_cmd640.c
Tejun Heo c7087652e1 libata-sff: clean up BMDMA initialization
When BMDMA initialization failed or BMDMA was not available for
whatever reason, bmdma_addr was left at zero and used as an indication
that BMDMA shouldn't be used.  This leads to the following problems.

p1. For BMDMA drivers which don't use traditional BMDMA register,
    ata_bmdma_mode_filter() incorrectly inhibits DMA modes.  Those
    drivers either have to inherit from ata_sff_port_ops or clear
    ->mode_filter explicitly.

p2. non-BMDMA drivers call into BMDMA PRD table allocation.  It
    doesn't actually allocate PRD table if bmdma_addr is not
    initialized but is still confusing.

p3. For BMDMA drivers which don't use traditional BMDMA register, some
    methods might not be invoked as expected (e.g. bmdma_stop from
    ata_sff_post_internal_cmd()).

p4. SFF drivers w/ custom DMA interface implement noop BMDMA ops
    worrying libata core might call into one of them.

These problems are caused by the muddy line between SFF and BMDMA and
the assumption that all BMDMA controllers initialize bmdma_addr.

This patch fixes p1 and p2 by removing the bmdma_addr assumption and
moving prd allocation to BMDMA port start.  Later patches will fix the
remaining issues.

This patch improves BMDMA initialization such that

* When BMDMA register initialization fails, falls back to PIO instead
  of failing.  ata_pci_bmdma_init() never fails now.

* When ata_pci_bmdma_init() falls back to PIO, it clears
  ap->mwdma_mask and udma_mask instead of depending on
  ata_bmdma_mode_filter().  This makes ata_bmdma_mode_filter()
  unnecessary thus resolving p1.

* ata_port_start() which actually is BMDMA specific is moved to
  ata_bmdma_port_start().  ata_port_start() and ata_sff_port_start()
  are killed.

* ata_sff_port_start32() is moved and renamed to
  ata_bmdma_port_start32().

Drivers which no longer call into PRD table allocation are...

  pdc_adma, sata_inic162x, sata_qstor, sata_sx4, pata_cmd640 and all
  drivers which inherit from ata_sff_port_ops.

pata_icside sets ->port_start to ATA_OP_NULL as it doesn't need PRD
but is a BMDMA controller and doesn't have custom port_start like
other such controllers.

Note that with the previous patch which makes all and only BMDMA
drivers inherit from ata_bmdma_port_ops, this change doesn't break
drivers which need PRD table.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2010-05-19 13:32:19 -04:00

271 lines
6.4 KiB
C

/*
* pata_cmd640.c - CMD640 PCI PATA for new ATA layer
* (C) 2007 Red Hat Inc
*
* Based upon
* linux/drivers/ide/pci/cmd640.c Version 1.02 Sep 01, 1996
*
* Copyright (C) 1995-1996 Linus Torvalds & authors (see driver)
*
* This drives only the PCI version of the controller. If you have a
* VLB one then we have enough docs to support it but you can write
* your own code.
*/
#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 <linux/gfp.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#define DRV_NAME "pata_cmd640"
#define DRV_VERSION "0.0.5"
struct cmd640_reg {
int last;
u8 reg58[ATA_MAX_DEVICES];
};
enum {
CFR = 0x50,
CNTRL = 0x51,
CMDTIM = 0x52,
ARTIM0 = 0x53,
DRWTIM0 = 0x54,
ARTIM23 = 0x57,
DRWTIM23 = 0x58,
BRST = 0x59
};
/**
* cmd640_set_piomode - set initial PIO mode data
* @ap: ATA port
* @adev: ATA device
*
* Called to do the PIO mode setup.
*/
static void cmd640_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
struct cmd640_reg *timing = ap->private_data;
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
struct ata_timing t;
const unsigned long T = 1000000 / 33;
const u8 setup_data[] = { 0x40, 0x40, 0x40, 0x80, 0x00 };
u8 reg;
int arttim = ARTIM0 + 2 * adev->devno;
struct ata_device *pair = ata_dev_pair(adev);
if (ata_timing_compute(adev, adev->pio_mode, &t, T, 0) < 0) {
printk(KERN_ERR DRV_NAME ": mode computation failed.\n");
return;
}
/* The second channel has shared timings and the setup timing is
messy to switch to merge it for worst case */
if (ap->port_no && pair) {
struct ata_timing p;
ata_timing_compute(pair, pair->pio_mode, &p, T, 1);
ata_timing_merge(&p, &t, &t, ATA_TIMING_SETUP);
}
/* Make the timings fit */
if (t.recover > 16) {
t.active += t.recover - 16;
t.recover = 16;
}
if (t.active > 16)
t.active = 16;
/* Now convert the clocks into values we can actually stuff into
the chip */
if (t.recover > 1)
t.recover--; /* 640B only */
else
t.recover = 15;
if (t.setup > 4)
t.setup = 0xC0;
else
t.setup = setup_data[t.setup];
if (ap->port_no == 0) {
t.active &= 0x0F; /* 0 = 16 */
/* Load setup timing */
pci_read_config_byte(pdev, arttim, &reg);
reg &= 0x3F;
reg |= t.setup;
pci_write_config_byte(pdev, arttim, reg);
/* Load active/recovery */
pci_write_config_byte(pdev, arttim + 1, (t.active << 4) | t.recover);
} else {
/* Save the shared timings for channel, they will be loaded
by qc_issue. Reloading the setup time is expensive so we
keep a merged one loaded */
pci_read_config_byte(pdev, ARTIM23, &reg);
reg &= 0x3F;
reg |= t.setup;
pci_write_config_byte(pdev, ARTIM23, reg);
timing->reg58[adev->devno] = (t.active << 4) | t.recover;
}
}
/**
* cmd640_qc_issue - command preparation hook
* @qc: Command to be issued
*
* Channel 1 has shared timings. We must reprogram the
* clock each drive 2/3 switch we do.
*/
static unsigned int cmd640_qc_issue(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
struct ata_device *adev = qc->dev;
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
struct cmd640_reg *timing = ap->private_data;
if (ap->port_no != 0 && adev->devno != timing->last) {
pci_write_config_byte(pdev, DRWTIM23, timing->reg58[adev->devno]);
timing->last = adev->devno;
}
return ata_sff_qc_issue(qc);
}
/**
* cmd640_port_start - port setup
* @ap: ATA port being set up
*
* The CMD640 needs to maintain private data structures so we
* allocate space here.
*/
static int cmd640_port_start(struct ata_port *ap)
{
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
struct cmd640_reg *timing;
timing = devm_kzalloc(&pdev->dev, sizeof(struct cmd640_reg), GFP_KERNEL);
if (timing == NULL)
return -ENOMEM;
timing->last = -1; /* Force a load */
ap->private_data = timing;
return 0;
}
static struct scsi_host_template cmd640_sht = {
ATA_PIO_SHT(DRV_NAME),
};
static struct ata_port_operations cmd640_port_ops = {
.inherits = &ata_sff_port_ops,
/* In theory xfer_noirq is not needed once we kill the prefetcher */
.sff_data_xfer = ata_sff_data_xfer_noirq,
.qc_issue = cmd640_qc_issue,
.cable_detect = ata_cable_40wire,
.set_piomode = cmd640_set_piomode,
.port_start = cmd640_port_start,
};
static void cmd640_hardware_init(struct pci_dev *pdev)
{
u8 ctrl;
/* CMD640 detected, commiserations */
pci_write_config_byte(pdev, 0x5B, 0x00);
/* PIO0 command cycles */
pci_write_config_byte(pdev, CMDTIM, 0);
/* 512 byte bursts (sector) */
pci_write_config_byte(pdev, BRST, 0x40);
/*
* A reporter a long time ago
* Had problems with the data fifo
* So don't run the risk
* Of putting crap on the disk
* For its better just to go slow
*/
/* Do channel 0 */
pci_read_config_byte(pdev, CNTRL, &ctrl);
pci_write_config_byte(pdev, CNTRL, ctrl | 0xC0);
/* Ditto for channel 1 */
pci_read_config_byte(pdev, ARTIM23, &ctrl);
ctrl |= 0x0C;
pci_write_config_byte(pdev, ARTIM23, ctrl);
}
static int cmd640_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
{
static const struct ata_port_info info = {
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = ATA_PIO4,
.port_ops = &cmd640_port_ops
};
const struct ata_port_info *ppi[] = { &info, NULL };
int rc;
rc = pcim_enable_device(pdev);
if (rc)
return rc;
cmd640_hardware_init(pdev);
return ata_pci_sff_init_one(pdev, ppi, &cmd640_sht, NULL, 0);
}
#ifdef CONFIG_PM
static int cmd640_reinit_one(struct pci_dev *pdev)
{
struct ata_host *host = dev_get_drvdata(&pdev->dev);
int rc;
rc = ata_pci_device_do_resume(pdev);
if (rc)
return rc;
cmd640_hardware_init(pdev);
ata_host_resume(host);
return 0;
}
#endif
static const struct pci_device_id cmd640[] = {
{ PCI_VDEVICE(CMD, 0x640), 0 },
{ },
};
static struct pci_driver cmd640_pci_driver = {
.name = DRV_NAME,
.id_table = cmd640,
.probe = cmd640_init_one,
.remove = ata_pci_remove_one,
#ifdef CONFIG_PM
.suspend = ata_pci_device_suspend,
.resume = cmd640_reinit_one,
#endif
};
static int __init cmd640_init(void)
{
return pci_register_driver(&cmd640_pci_driver);
}
static void __exit cmd640_exit(void)
{
pci_unregister_driver(&cmd640_pci_driver);
}
MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("low-level driver for CMD640 PATA controllers");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, cmd640);
MODULE_VERSION(DRV_VERSION);
module_init(cmd640_init);
module_exit(cmd640_exit);