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@xxxxxxxxx>
--- old/drivers/ata/sata_mv.c 2009-02-12 22:38:24.000000000 -0500
+++ upstream/drivers/ata/sata_mv.c 2009-02-12 22:47:59.000000000 -0500
@@ -1822,6 +1822,105 @@
}
/**
+ * 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 @@
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);
}
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