/*
* pata_ns87415.c - NS87415 (non PARISC) PATA
*
* (C) 2005 Red Hat <alan@redhat.com>
*
* This is a fairly generic MWDMA controller. It has some limitations
* as it requires timing reloads on PIO/DMA transitions but it is otherwise
* fairly well designed.
*
* This driver assumes the firmware has left the chip in a valid ST506
* compliant state, either legacy IRQ 14/15 or native INTA shared. You
* may need to add platform code if your system fails to do this.
*
* The same cell appears in the 87560 controller used by some PARISC
* systems. This has its own special mountain of errata.
*
* TODO:
* Test PARISC SuperIO
* Get someone to test on SPARC
* Implement lazy pio/dma switching for better performance
* 8bit shared timing.
* See if we need to kill the FIFO for ATAPI
*/
#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/device.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#include <linux/ata.h>
#define DRV_NAME "pata_ns87415"
#define DRV_VERSION "0.0.1"
/**
* ns87415_set_mode - Initialize host controller mode timings
* @ap: Port whose timings we are configuring
* @adev: Device whose timings we are configuring
* @mode: Mode to set
*
* Program the mode registers for this controller, channel and
* device. Because the chip is quite an old design we have to do this
* for PIO/DMA switches.
*
* LOCKING:
* None (inherited from caller).
*/
static void ns87415_set_mode(struct ata_port *ap, struct ata_device *adev, u8 mode)
{
struct pci_dev *dev = to_pci_dev(ap->host->dev);
int unit = 2 * ap->port_no + adev->devno;
int timing = 0x44 + 2 * unit;
unsigned long T = 1000000000 / 33333; /* PCI clocks */
struct ata_timing t;
u16 clocking;
u8 iordy;
u8 status;
/* Timing register format is 17 - low nybble read timing with
the high nybble being 16 - x for recovery time in PCI clocks */
ata_timing_compute(adev, adev->pio_mode, &t, T, 0);
clocking = 17 - clamp_val(t.active, 2, 17);
clocking |= (16 - clamp_val(t.recover, 1, 16)) << 4;
/* Use the same timing for read and write bytes */
clocking |= (clocking << 8);
pci_write_config_word(dev, timing, clocking);
/* Set the IORDY enable versus DMA enable on or off properly */
pci_read_config_byte(dev, 0x42, &iordy);
iordy &= ~(1 << (4 + unit));
if (mode >= XFER_MW_DMA_0 || !ata_pio_need_iordy(adev))
iordy |= (1 << (4 + unit));
/* Paranoia: We shouldn't ever get here with busy write buffers
but if so wait */
pci_read_config_byte(dev, 0x43, &status);
while (status & 0x03) {
udelay(1);
pci_read_config_byte(dev, 0x43, &status);
}
/* Flip the IORDY/DMA bits now we are sure the write buffers are
clear */
pci_write_config_byte(dev, 0x42, iordy);
/* TODO: Set byte 54 command timing to the best 8bit
mode shared by all four devices */
}
/**
* ns87415_set_piomode - Initialize host controller PATA PIO timings
* @ap: Port whose timings we are configuring
* @adev: Device to program
*
* Set PIO mode for device, in host controller PCI config space.
*
* LOCKING:
* None (inherited from caller).
*/
static void ns87415_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
ns87415_set_mode(ap, adev, adev->pio_mode);
}
/**
* ns87415_bmdma_setup - Set up DMA
* @qc: Command block
*
* Set up for bus masterng DMA. We have to do this ourselves
* rather than use the helper due to a chip erratum
*/
static void ns87415_bmdma_setup(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
unsigned int rw = (qc->tf.flags & ATA_TFLAG_WRITE);
u8 dmactl;
/* load PRD table addr. */
mb(); /* make sure PRD table writes are visible to controller */
iowrite32(ap->prd_dma, ap->ioaddr.bmdma_addr + ATA_DMA_TABLE_OFS);
/* specify data direction, triple-check start bit is clear */
dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
dmactl &= ~(ATA_DMA_WR | ATA_DMA_START);
/* Due to an erratum we need to write these bits to the wrong
place - which does save us an I/O bizarrely */
dmactl |= ATA_DMA_INTR | ATA_DMA_ERR;
if (!rw)
dmactl |= ATA_DMA_WR;
iowrite8(dmactl, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
/* issue r/w command */
ap->ops->sff_exec_command(ap, &qc->tf);
}
/**
* ns87415_bmdma_start - Begin DMA transfer
* @qc: Command block
*
* Switch the timings for the chip and set up for a DMA transfer
* before the DMA burst begins.
*
* FIXME: We should do lazy switching on bmdma_start versus
* ata_pio_data_xfer for better performance.
*/
static void ns87415_bmdma_start(struct ata_queued_cmd *qc)
{
ns87415_set_mode(qc->ap, qc->dev, qc->dev->dma_mode);
ata_bmdma_start(qc);
}
/**
* ns87415_bmdma_stop - End DMA transfer
* @qc: Command block
*
* End DMA mode and switch the controller back into PIO mode
*/
static void ns87415_bmdma_stop(struct ata_queued_cmd *qc)
{
ata_bmdma_stop(qc);
ns87415_set_mode(qc->ap, qc->dev, qc->dev->pio_mode);
}
/**
* ns87415_irq_clear - Clear interrupt
* @ap: Channel to clear
*
* Erratum: Due to a chip bug regisers 02 and 0A bit 1 and 2 (the
* error bits) are reset by writing to register 00 or 08.
*/
static void ns87415_irq_clear(struct ata_port *ap)
{
void __iomem *mmio = ap->ioaddr.bmdma_addr;
if (!mmio)
return;
iowrite8((ioread8(mmio + ATA_DMA_CMD) | ATA_DMA_INTR | ATA_DMA_ERR),
mmio + ATA_DMA_CMD);
}
/**
* ns87415_check_atapi_dma - ATAPI DMA filter
* @qc: Command block
*
* Disable ATAPI DMA (for now). We may be able to do DMA if we
* kill the prefetching. This isn't clear.
*/
static int ns87415_check_atapi_dma(struct ata_queued_cmd *qc)
{
return -EOPNOTSUPP;
}
#if defined(CONFIG_SUPERIO)
/* SUPERIO 87560 is a PoS chip that NatSem denies exists.
* Unfortunately, it's built-in on all Astro-based PA-RISC workstations
* which use the integrated NS87514 cell for CD-ROM support.
* i.e we have to support for CD-ROM installs.
* See drivers/parisc/superio.c for more gory details.
*
* Workarounds taken from drivers/ide/pci/ns87415.c
*/
#include <asm/superio.h>
#define SUPERIO_IDE_MAX_RETRIES 25
/**
* ns87560_read_buggy - workaround buggy Super I/O chip
* @port: Port to read
*
* Work around chipset problems in the 87560 SuperIO chip
*/
static u8 ns87560_read_buggy(void __iomem *port)
{
u8 tmp;
int retries = SUPERIO_IDE_MAX_RETRIES;
do {
tmp = ioread8(port);
if (tmp != 0)
return tmp;
udelay(50);
} while(retries-- > 0);
return tmp;
}
/**
* ns87560_check_status
* @ap: channel to check
*
* Return the status of the channel working around the
* 87560 flaws.
*/
static u8 ns87560_check_status(struct ata_port *ap)
{
return ns87560_read_buggy(ap->ioaddr.status_addr);
}
/**
* ns87560_tf_read - input device's ATA taskfile shadow registers
* @ap: Port from which input is read
* @tf: ATA taskfile register set for storing input
*
* Reads ATA taskfile registers for currently-selected device
* into @tf. Work around the 87560 bugs.
*
* LOCKING:
* Inherited from caller.
*/
void ns87560_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
{
struct ata_ioports *ioaddr = &ap->ioaddr;
tf->command = ns87560_check_status(ap);
tf->feature = ioread8(ioaddr->error_addr);
tf->nsect = ioread8(ioaddr->nsect_addr);
tf->lbal = ioread8(ioaddr->lbal_addr);
tf->lbam = ioread8(ioaddr->lbam_addr);
tf->lbah = ioread8(ioaddr->lbah_addr);
tf->device = ns87560_read_buggy(ioaddr->device_addr);
if (tf->flags & ATA_TFLAG_LBA48) {
iowrite8(tf->ctl | ATA_HOB, ioaddr->ctl_addr);
tf->hob_feature = ioread8(ioaddr->error_addr);
tf->hob_nsect = ioread8(ioaddr->nsect_addr);
tf->hob_lbal = ioread8(ioaddr->lbal_addr);
tf->hob_lbam = ioread8(ioaddr->lbam_addr);
tf->hob_lbah = ioread8(ioaddr->lbah_addr);
iowrite8(tf->ctl, ioaddr->ctl_addr);
ap->last_ctl = tf->ctl;
}
}
/**
* ns87560_bmdma_status
* @ap: channel to check
*
* Return the DMA status of the channel working around the
* 87560 flaws.
*/
static u8 ns87560_bmdma_status(struct ata_port *ap)
{
return ns87560_read_buggy(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
}
#endif /* 87560 SuperIO Support */
static struct ata_port_operations ns87415_pata_ops = {
.inherits = &ata_bmdma_port_ops,
.check_atapi_dma = ns87415_check_atapi_dma,
.bmdma_setup = ns87415_bmdma_setup,
.bmdma_start = ns87415_bmdma_start,
.bmdma_stop = ns87415_bmdma_stop,
.sff_irq_clear = ns87415_irq_clear,
.cable_detect = ata_cable_40wire,
.set_piomode = ns87415_set_piomode,
};
#if defined(CONFIG_SUPERIO)
static struct ata_port_operations ns87560_pata_ops = {
.inherits = &ns87415_pata_ops,
.sff_tf_read = ns87560_tf_read,
.sff_check_status = ns87560_check_status,
.bmdma_status = ns87560_bmdma_status,
};
#endif
static struct scsi_host_template ns87415_sht = {
ATA_BMDMA_SHT(DRV_NAME),
};
/**
* ns87415_init_one - Register 87415 ATA PCI device with kernel services
* @pdev: PCI device to register
* @ent: Entry in ns87415_pci_tbl matching with @pdev
*
* Called from kernel PCI layer. We probe for combined mode (sigh),
* and then hand over control to libata, for it to do the rest.
*
* LOCKING:
* Inherited from PCI layer (may sleep).
*
* RETURNS:
* Zero on success, or -ERRNO value.
*/
static int ns87415_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
{
static int printed_version;
static const struct ata_port_info info = {
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = 0x1f, /* pio0-4 */
.mwdma_mask = 0x07, /* mwdma0-2 */
.port_ops = &ns87415_pata_ops,
};
const struct ata_port_info *ppi[] = { &info, NULL };
int rc;
#if defined(CONFIG_SUPERIO)
static const struct ata_port_info info87560 = {
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = 0x1f, /* pio0-4 */
.mwdma_mask = 0x07, /* mwdma0-2 */
.port_ops = &ns87560_pata_ops,
};
if (PCI_SLOT(pdev->devfn) == 0x0E)
ppi[0] = &info87560;
#endif
if (!printed_version++)
dev_printk(KERN_DEBUG, &pdev->dev,
"version " DRV_VERSION "\n");
rc = pcim_enable_device(pdev);
if (rc)
return rc;
/* Select 512 byte sectors */
pci_write_config_byte(pdev, 0x55, 0xEE);
/* Select PIO0 8bit clocking */
pci_write_config_byte(pdev, 0x54, 0xB7);
return ata_pci_sff_init_one(pdev, ppi, &ns87415_sht, NULL);
}
static const struct pci_device_id ns87415_pci_tbl[] = {
{ PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_87415), },
{ } /* terminate list */
};
static struct pci_driver ns87415_pci_driver = {
.name = DRV_NAME,
.id_table = ns87415_pci_tbl,
.probe = ns87415_init_one,
.remove = ata_pci_remove_one,
#ifdef CONFIG_PM
.suspend = ata_pci_device_suspend,
.resume = ata_pci_device_resume,
#endif
};
static int __init ns87415_init(void)
{
return pci_register_driver(&ns87415_pci_driver);
}
static void __exit ns87415_exit(void)
{
pci_unregister_driver(&ns87415_pci_driver);
}
module_init(ns87415_init);
module_exit(ns87415_exit);
MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("ATA low-level driver for NS87415 controllers");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, ns87415_pci_tbl);
MODULE_VERSION(DRV_VERSION);
