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Diffstat (limited to 'drivers/ata/pata_ns87415.c')
-rw-r--r--drivers/ata/pata_ns87415.c415
1 files changed, 415 insertions, 0 deletions
diff --git a/drivers/ata/pata_ns87415.c b/drivers/ata/pata_ns87415.c
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+++ b/drivers/ata/pata_ns87415.c
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+/*
+ * pata_ns87415.c - NS87415 (non PARISC) PATA
+ *
+ * (C) 2005 Red Hat <alan@lxorguk.ukuu.org.uk>
+ *
+ * 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);
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