diff options
author | Mark Lord <mlord@pobox.com> | 2009-02-25 20:19:20 (GMT) |
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committer | Jeff Garzik <jgarzik@redhat.com> | 2009-03-25 02:02:41 (GMT) |
commit | 70f8b79cf3a2eb892a01271fdfbb1903c0c982a8 (patch) | |
tree | ca959654f45cf57760470a17742a530a0a1e21b6 /drivers | |
parent | 1a660164c291f41b2aa853a7269b310933574ef9 (diff) | |
download | linux-fsl-qoriq-70f8b79cf3a2eb892a01271fdfbb1903c0c982a8.tar.xz |
[libata] sata_mv: Implement direct FIS transmission via mv_qc_issue_fis().
This is initially needed to work around NCQ errata,
whereby the READ_LOG_EXT command sometimes fails
when issued in the traditional (sff) fashion.
Portions of this code will likely be reused for
implementation of the target mode feature later on.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/ata/sata_mv.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c index 542e244..8cad3b2 100644 --- a/drivers/ata/sata_mv.c +++ b/drivers/ata/sata_mv.c @@ -1822,6 +1822,105 @@ static u8 mv_sff_check_status(struct ata_port *ap) } /** + * mv_send_fis - Send a FIS, using the "Vendor-Unique FIS" register + * @fis: fis to be sent + * @nwords: number of 32-bit words in the fis + */ +static unsigned int mv_send_fis(struct ata_port *ap, u32 *fis, int nwords) +{ + void __iomem *port_mmio = mv_ap_base(ap); + u32 ifctl, old_ifctl, ifstat; + int i, timeout = 200, final_word = nwords - 1; + + /* Initiate FIS transmission mode */ + old_ifctl = readl(port_mmio + SATA_IFCTL_OFS); + ifctl = 0x100 | (old_ifctl & 0xf); + writelfl(ifctl, port_mmio + SATA_IFCTL_OFS); + + /* Send all words of the FIS except for the final word */ + for (i = 0; i < final_word; ++i) + writel(fis[i], port_mmio + VENDOR_UNIQUE_FIS_OFS); + + /* Flag end-of-transmission, and then send the final word */ + writelfl(ifctl | 0x200, port_mmio + SATA_IFCTL_OFS); + writelfl(fis[final_word], port_mmio + VENDOR_UNIQUE_FIS_OFS); + + /* + * Wait for FIS transmission to complete. + * This typically takes just a single iteration. + */ + do { + ifstat = readl(port_mmio + SATA_IFSTAT_OFS); + } while (!(ifstat & 0x1000) && --timeout); + + /* Restore original port configuration */ + writelfl(old_ifctl, port_mmio + SATA_IFCTL_OFS); + + /* See if it worked */ + if ((ifstat & 0x3000) != 0x1000) { + ata_port_printk(ap, KERN_WARNING, + "%s transmission error, ifstat=%08x\n", + __func__, ifstat); + return AC_ERR_OTHER; + } + return 0; +} + +/** + * mv_qc_issue_fis - Issue a command directly as a FIS + * @qc: queued command to start + * + * Note that the ATA shadow registers are not updated + * after command issue, so the device will appear "READY" + * if polled, even while it is BUSY processing the command. + * + * So we use a status hook to fake ATA_BUSY until the drive changes state. + * + * Note: we don't get updated shadow regs on *completion* + * of non-data commands. So avoid sending them via this function, + * as they will appear to have completed immediately. + * + * GEN_IIE has special registers that we could get the result tf from, + * but earlier chipsets do not. For now, we ignore those registers. + */ +static unsigned int mv_qc_issue_fis(struct ata_queued_cmd *qc) +{ + struct ata_port *ap = qc->ap; + struct mv_port_priv *pp = ap->private_data; + struct ata_link *link = qc->dev->link; + u32 fis[5]; + int err = 0; + + ata_tf_to_fis(&qc->tf, link->pmp, 1, (void *)fis); + err = mv_send_fis(ap, fis, sizeof(fis) / sizeof(fis[0])); + if (err) + return err; + + switch (qc->tf.protocol) { + case ATAPI_PROT_PIO: + pp->pp_flags |= MV_PP_FLAG_FAKE_ATA_BUSY; + /* fall through */ + case ATAPI_PROT_NODATA: + ap->hsm_task_state = HSM_ST_FIRST; + break; + case ATA_PROT_PIO: + pp->pp_flags |= MV_PP_FLAG_FAKE_ATA_BUSY; + if (qc->tf.flags & ATA_TFLAG_WRITE) + ap->hsm_task_state = HSM_ST_FIRST; + else + ap->hsm_task_state = HSM_ST; + break; + default: + ap->hsm_task_state = HSM_ST_LAST; + break; + } + + if (qc->tf.flags & ATA_TFLAG_POLLING) + ata_pio_queue_task(ap, qc, 0); + return 0; +} + +/** * mv_qc_issue - Initiate a command to the host * @qc: queued command to start * @@ -1896,6 +1995,23 @@ static unsigned int mv_qc_issue(struct ata_queued_cmd *qc) mv_stop_edma(ap); mv_clear_and_enable_port_irqs(ap, mv_ap_base(ap), port_irqs); mv_pmp_select(ap, qc->dev->link->pmp); + + if (qc->tf.command == ATA_CMD_READ_LOG_EXT) { + struct mv_host_priv *hpriv = ap->host->private_data; + /* + * Workaround for 88SX60x1 FEr SATA#25 (part 2). + * + * After any NCQ error, the READ_LOG_EXT command + * from libata-eh *must* use mv_qc_issue_fis(). + * Otherwise it might fail, due to chip errata. + * + * Rather than special-case it, we'll just *always* + * use this method here for READ_LOG_EXT, making for + * easier testing. + */ + if (IS_GEN_II(hpriv)) + return mv_qc_issue_fis(qc); + } return ata_sff_qc_issue(qc); } |