Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753077Ab0DGH5i (ORCPT ); Wed, 7 Apr 2010 03:57:38 -0400 Received: from sdcmail01.amcc.com ([198.137.200.72]:23845 "EHLO sdcmail01.amcc.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751033Ab0DGH5b convert rfc822-to-8bit (ORCPT ); Wed, 7 Apr 2010 03:57:31 -0400 X-IronPort-AV: E=Sophos;i="4.51,377,1267430400"; d="scan'208";a="25583535" X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Subject: RE: [PATCH] 460EX on-chip SATA driver < resubmission : 02> Date: Wed, 7 Apr 2010 00:57:28 -0700 Message-ID: In-Reply-To: <4BBB5045.5020004@pobox.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: thread-topic: [PATCH] 460EX on-chip SATA driver < resubmission : 02> Thread-Index: AcrVnCD6kmNo/NRGQbW17ql3hN4ACgAi6GvQ References: <201004061141.o36BfTsr028163@amcc.com> <4BBB5045.5020004@pobox.com> From: "Rupjyoti Sarmah" To: "Jeff Garzik" Cc: , , , Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 19756 Lines: 728 Hi Jeff, Thanks. I would go through your suggestions and resubmit a newer version. Regards, Rup -----Original Message----- From: Jeff Garzik [mailto:jgpobox@gmail.com] On Behalf Of Jeff Garzik Sent: Tuesday, April 06, 2010 8:46 PM To: Rupjyoti Sarmah Cc: linux-ide@vger.kernel.org; linux-kernel@vger.kernel.org; sr@denx.de; linuxppc-dev@ozlabs.org Subject: Re: [PATCH] 460EX on-chip SATA driver < resubmission : 02> On 04/06/2010 07:41 AM, Rupjyoti Sarmah wrote: General comment: remove "inline" and let the compiler select those functions that need it. > +struct sata_dwc_host_priv { > + > + void __iomem *scr_addr_sstatus; > + u32 sata_dwc_sactive_issued; > + u32 sata_dwc_sactive_queued; > + u32 dma_interrupt_count; > + struct ahb_dma_regs *sata_dma_regs; > + struct device *dwc_dev; > + > +}; use proper indentation (separate type from member name with tabs) > +struct sata_dwc_host_priv host_pvt; > + > +/* > + * Prototypes > + */ > +static void sata_dwc_bmdma_start_by_tag(struct ata_queued_cmd *qc, u8 tag); > +static int sata_dwc_qc_complete(struct ata_port *ap, struct ata_queued_cmd *qc, > + u32 check_status); > +static void sata_dwc_dma_xfer_complete(struct ata_port *ap, u32 check_status); > +static void sata_dwc_port_stop(struct ata_port *ap); > +static void sata_dwc_clear_dmacr(struct sata_dwc_device_port *hsdevp, u8 tag); > + > +static int dma_dwc_init(struct sata_dwc_device *hsdev, int irq); > +static void dma_dwc_exit(struct sata_dwc_device *hsdev); > +static int dma_dwc_xfer_setup(struct scatterlist *sg, int num_elems, > + struct lli *lli, dma_addr_t dma_lli, > + void __iomem *addr, int dir); > +static void dma_dwc_xfer_start(int dma_ch); > + > +static const char *dir_2_txt(enum dma_data_direction dir) > +{ > + switch (dir) { > + case DMA_BIDIRECTIONAL: > + return "bi"; > + case DMA_FROM_DEVICE: > + return "from"; > + case DMA_TO_DEVICE: > + return "to"; > + case DMA_NONE: > + return "none"; > + default: > + return "err"; > + } > +} > + > +static const char *prot_2_txt(enum ata_tf_protocols protocol) > +{ > + switch (protocol) { > + case ATA_PROT_UNKNOWN: > + return "unknown"; > + case ATA_PROT_NODATA: > + return "nodata"; > + case ATA_PROT_PIO: > + return "pio"; > + case ATA_PROT_DMA: > + return "dma"; > + case ATA_PROT_NCQ: > + return "ncq"; > + case ATAPI_PROT_PIO: > + return "atapi pio"; > + case ATAPI_PROT_NODATA: > + return "atapi nodata"; > + case ATAPI_PROT_DMA: > + return "atapi dma"; > + default: > + return "err"; > + } > +} > + > +inline const char *ata_cmd_2_txt(const struct ata_taskfile *tf) > +{ > + switch (tf->command) { > + case ATA_CMD_CHK_POWER: > + return "ATA_CMD_CHK_POWER"; > + case ATA_CMD_EDD: > + return "ATA_CMD_EDD"; > + case ATA_CMD_FLUSH: > + return "ATA_CMD_FLUSH"; > + case ATA_CMD_FLUSH_EXT: > + return "ATA_CMD_FLUSH_EXT"; > + case ATA_CMD_ID_ATA: > + return "ATA_CMD_ID_ATA"; > + case ATA_CMD_ID_ATAPI: > + return "ATA_CMD_ID_ATAPI"; > + case ATA_CMD_FPDMA_READ: > + return "ATA_CMD_FPDMA_READ"; > + case ATA_CMD_FPDMA_WRITE: > + return "ATA_CMD_FPDMA_WRITE"; > + case ATA_CMD_READ: > + return "ATA_CMD_READ"; > + case ATA_CMD_READ_EXT: > + return "ATA_CMD_READ_EXT"; > + case ATA_CMD_READ_NATIVE_MAX_EXT: > + return "ATA_CMD_READ_NATIVE_MAX_EXT"; > + case ATA_CMD_VERIFY_EXT: > + return "ATA_CMD_VERIFY_EXT"; > + case ATA_CMD_WRITE: > + return "ATA_CMD_WRITE"; > + case ATA_CMD_WRITE_EXT: > + return "ATA_CMD_WRITE_EXT"; > + case ATA_CMD_PIO_READ: > + return "ATA_CMD_PIO_READ"; > + case ATA_CMD_PIO_READ_EXT: > + return "ATA_CMD_PIO_READ_EXT"; > + case ATA_CMD_PIO_WRITE: > + return "ATA_CMD_PIO_WRITE"; > + case ATA_CMD_PIO_WRITE_EXT: > + return "ATA_CMD_PIO_WRITE_EXT"; > + case ATA_CMD_SET_FEATURES: > + return "ATA_CMD_SET_FEATURES"; > + case ATA_CMD_PACKET: > + return "ATA_CMD_PACKET"; > + default: > + return "ATA_CMD_???"; > + } use ata_get_cmd_descript() rather than duplicating it > +static irqreturn_t dma_dwc_interrupt(int irq, void *hsdev_instance) > +{ > + int chan; > + u32 tfr_reg, err_reg; > + > + struct sata_dwc_device *hsdev = > + (struct sata_dwc_device *) hsdev_instance; > + struct ata_host *host = (struct ata_host *) hsdev->host; > + struct ata_port *ap; > + struct sata_dwc_device_port *hsdevp; > + u8 tag = 0; > + unsigned int port = 0; > + struct sata_dwc_host_priv *hp; > + hp = kmalloc(sizeof(*hp), GFP_KERNEL); 1) interrupt is not GFP_KERNEL 2) you must failure kmalloc failure 3) it is not clear to me where you initialize this structure??? > + spin_lock(&host->lock); > + > + ap = host->ports[port]; > + hsdevp = HSDEVP_FROM_AP(ap); > + tag = ap->link.active_tag; > + > + tfr_reg = in_le32(&(host_pvt.sata_dma_regs->interrupt_status.tfr.low)); > + err_reg = in_le32(&(host_pvt.sata_dma_regs-> \ > + interrupt_status.error.low)); > + > + dev_dbg(ap->dev, "eot=0x%08x err=0x%08x pending=%d active port=%d\n", > + tfr_reg, err_reg, hsdevp->dma_pending[tag], port); > + > + for (chan = 0; chan< DMA_NUM_CHANS; chan++) { > + /* Check for end-of-transfer interrupt. */ > + if (tfr_reg& DMA_CHANNEL(chan)) { > + /* Each DMA command produces 2 interrupts. Only > + * complete the command after both interrupts have been > + * seen. (See sata_dwc_isr()) > + */ > + hp->dma_interrupt_count++; > + > + sata_dwc_clear_dmacr(hsdevp, tag); > + > + if (hsdevp->dma_pending[tag] == > + SATA_DWC_DMA_PENDING_NONE) { > + dev_err(ap->dev, "DMA not pending eot=0x%08x " > + "err=0x%08x tag=0x%02x pending=%d\n", > + tfr_reg, err_reg, tag, > + hsdevp->dma_pending[tag]); > + } > + > + if ((hp->dma_interrupt_count) % 2 == 0) > + sata_dwc_dma_xfer_complete(ap, 1); > + > + /* Clear the interrupt */ > + out_le32(&(host_pvt.sata_dma_regs-> \ > + interrupt_clear.tfr.low), DMA_CHANNEL(chan)); > + } > + > + /* Check for error interrupt. */ > + if (err_reg& DMA_CHANNEL(chan)) { > + /* Error handler ! */ > + dev_err(ap->dev, "error interrupt err_reg=0x%08x\n", > + err_reg); > + > + /* Clear the interrupt. */ > + out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.\ > + error.low), DMA_CHANNEL(chan)); > + } > + } > + > + spin_unlock(&host->lock); > + kfree(hp); > + > + return IRQ_HANDLED; > +} > +static inline void clear_serror(void) > +{ > + out_le32((host_pvt.scr_addr_sstatus) + 4, > + in_le32((host_pvt.scr_addr_sstatus) + 4)); > +} this should be defined in terms of scr_read/write functions defined previously. > +/* See ahci.c */ > +static void sata_dwc_error_intr(struct ata_port *ap, > + struct sata_dwc_device *hsdev, uint intpr) > +{ > + struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap); > + struct ata_eh_info *ehi =&ap->link.eh_info; > + unsigned int err_mask = 0, action = 0; > + struct ata_queued_cmd *qc; > + u32 serror; > + u8 status, tag; > + u32 err_reg; > + struct sata_dwc_host_priv *hp; > + hp = kmalloc(sizeof(*hp), GFP_KERNEL); ditto above 3 comments about 'hp' > + ata_ehi_clear_desc(ehi); > + > + serror = core_scr_read(SCR_ERROR); > + status = ap->ops->sff_check_status(ap); > + > + err_reg = in_le32(&(host_pvt.sata_dma_regs-> \ > + interrupt_status.error.low)); > + tag = ap->link.active_tag; > + > + dev_err(ap->dev, "%s SCR_ERROR=0x%08x intpr=0x%08x status=0x%08x " > + "dma_intp=%d pending=%d issued=%d dma_err_status=0x%08x\n", > + __func__, serror, intpr, status, hp->dma_interrupt_count, > + hsdevp->dma_pending[tag], hsdevp->cmd_issued[tag], err_reg); > + > + /* Clear error register and interrupt bit */ > + clear_serror(); > + clear_interrupt_bit(hsdev, SATA_DWC_INTPR_ERR); > + > + /* This is the only error happening now. */ > + err_mask |= AC_ERR_HOST_BUS; > + action |= ATA_EH_RESET; > + > + /* Pass this on to EH */ > + ehi->serror |= serror; > + ehi->action |= action; > + > + qc = ata_qc_from_tag(ap, tag); > + if (qc) > + qc->err_mask |= err_mask; > + else > + ehi->err_mask |= err_mask; > + > + ata_port_abort(ap); > + kfree(hp); > + > + /* > + if (irq_stat& PORT_IRQ_FREEZE) > + ata_port_freeze(ap); > + else > + ata_port_abort(ap); > + */ > +} > + > +/* > + * Function : sata_dwc_isr > + * arguments : irq, void *dev_instance, struct pt_regs *regs > + * Return value : irqreturn_t - status of IRQ > + * This Interrupt handler called via port ops registered function. > + * .irq_handler = sata_dwc_isr > + */ > +static irqreturn_t sata_dwc_isr(int irq, void *dev_instance) > +{ > + u8 status, tag; > + int handled, num_processed, port = 0; > + uint intpr, sactive, sactive2, tag_mask; > + struct sata_dwc_device_port *hsdevp; > + struct ata_host *host = (struct ata_host *)dev_instance; > + struct sata_dwc_device *hsdev = HSDEV_FROM_HOST(host); > + struct ata_port *ap; > + struct ata_queued_cmd *qc; > + struct sata_dwc_host_priv *hp; > + > + hp = kmalloc(sizeof(*hp), GFP_KERNEL); > + hp->sata_dwc_sactive_issued = 0; ditto above 3 comments about 'hp' > + spin_lock(&host->lock); > + > + /* Read the interrupt register */ > + intpr = in_le32(&hsdev->sata_dwc_regs->intpr); > + > + ap = host->ports[port]; > + hsdevp = HSDEVP_FROM_AP(ap); > + > + dev_dbg(ap->dev, "%s intpr=0x%08x active_tag=%d\n", __func__, intpr, > + ap->link.active_tag); > + > + /* Check for error interrupt */ > + if (intpr& SATA_DWC_INTPR_ERR) { > + sata_dwc_error_intr(ap, hsdev, intpr); > + handled = 1; > + goto DONE; > + } > + > + /* Check for DMA SETUP FIS (FP DMA) interrupt */ > + if (intpr& SATA_DWC_INTPR_NEWFP) { > + clear_interrupt_bit(hsdev, SATA_DWC_INTPR_NEWFP); > + > + tag = (u8)(in_le32(&hsdev->sata_dwc_regs->fptagr)); > + dev_dbg(ap->dev, "%s: NEWFP tag=%d\n", __func__, tag); > + if (hsdevp->cmd_issued[tag] != SATA_DWC_CMD_ISSUED_PEND) > + dev_warn(ap->dev, "CMD tag=%d not pending?\n", tag); > + > + hp->sata_dwc_sactive_issued |= qcmd_tag_to_mask(tag); > + > + qc = ata_qc_from_tag(ap, tag); > + /* Start FP DMA for NCQ command. At this point the tag is the > + * active tag. It is the tag that matches the command about to > + * be completed. > + */ > + qc->ap->link.active_tag = tag; > + sata_dwc_bmdma_start_by_tag(qc, tag); > + > + handled = 1; > + goto DONE; > + } > + sactive = core_scr_read(SCR_ACTIVE); > + tag_mask = (hp->sata_dwc_sactive_issued | sactive) ^ sactive; > + > + /* If no sactive issued and tag_mask is zero then this is not NCQ */ > + if (hp->sata_dwc_sactive_issued == 0&& tag_mask == 0) { > + if (ap->link.active_tag == ATA_TAG_POISON) > + tag = 0; > + else > + tag = ap->link.active_tag; > + qc = ata_qc_from_tag(ap, tag); > + > + /* DEV interrupt w/ no active qc? */ > + if (unlikely(!qc || (qc->tf.flags& ATA_TFLAG_POLLING))) { > + dev_err(ap->dev, "%s interrupt with no active qc " > + "qc=%p\n", __func__, qc); > + ata_sff_check_status(ap); > + handled = 1; > + goto DONE; > + } > + > + status = ap->ops->sff_check_status(ap); either call ->sff_check_status or ata_sff_check_status(), pick one. in above code, you do both. > + qc->ap->link.active_tag = tag; > + hsdevp->cmd_issued[tag] = SATA_DWC_CMD_ISSUED_NOT; > + > + if (status& ATA_ERR) { > + dev_dbg(ap->dev, "interrupt ATA_ERR (0x%x)\n", status); > + sata_dwc_qc_complete(ap, qc, 1); > + handled = 1; > + goto DONE; > + } > + > + dev_dbg(ap->dev, "%s non-NCQ cmd interrupt, protocol: %s\n", > + __func__, prot_2_txt(qc->tf.protocol)); > +DRVSTILLBUSY: > + if (ata_is_dma(qc->tf.protocol)) { > + /* Each DMA transaction produces 2 interrupts. The DMAC > + * transfer complete interrupt and the SATA controller > + * operation done interrupt. The command should be > + * completed only after both interrupts are seen. > + */ > + hp->dma_interrupt_count++; > + if (hsdevp->dma_pending[tag] == \ > + SATA_DWC_DMA_PENDING_NONE) { > + dev_err(ap->dev, "%s: DMA not pending " > + "intpr=0x%08x status=0x%08x pending=%d\n", > + __func__, intpr, status, > + hsdevp->dma_pending[tag]); > + } > + > + if ((hp->dma_interrupt_count) % 2 == 0) > + sata_dwc_dma_xfer_complete(ap, 1); > + } else if (ata_is_pio(qc->tf.protocol)) { > + ata_sff_hsm_move(ap, qc, status, 0); > + handled = 1; > + goto DONE; > + } else { > + if (unlikely(sata_dwc_qc_complete(ap, qc, 1))) > + goto DRVSTILLBUSY; > + } > + > + handled = 1; > + goto DONE; > + } > + > + /* > + * This is NCQ command. At this point we need to figure out for which > + * tags we have gotten a completion interrupt. One interrupt may serve > + * as completion for more than one operation when commands are queued > + * (NCQ). We need to process each completed command. > + */ > + > +PROCESS: /* process completed commands */ > + sactive = core_scr_read(SCR_ACTIVE); > + tag_mask = (hp->sata_dwc_sactive_issued | sactive) ^ sactive; > + > + if (sactive != 0 || hp->sata_dwc_sactive_issued> 1 || tag_mask> 1) { > + dev_dbg(ap->dev, "%s NCQ:sactive=0x%08x sactive_issued=0x%08x " > + "tag_mask=0x%08x\n", __func__, sactive, > + hp->sata_dwc_sactive_issued, tag_mask); > + } > + > + if ((tag_mask | (hp->sata_dwc_sactive_issued)) != \ > + (hp->sata_dwc_sactive_issued)) { > + dev_warn(ap->dev, "Bad tag mask? sactive=0x%08x " > + "hp->sata_dwc_sactive_issued=0x%08x tag_mask=0x%08x\n" > + , sactive, hp->sata_dwc_sactive_issued, tag_mask); > + } > + > + /* read just to clear ... not bad if currently still busy */ > + status = ap->ops->sff_check_status(ap); > + dev_dbg(ap->dev, "%s ATA status register=0x%x\n", __func__, status); > + > + tag = 0; > + num_processed = 0; > + while (tag_mask) { > + num_processed++; > + while (!(tag_mask& 0x00000001)) { > + tag++; > + tag_mask>>= 1; > + } > + tag_mask&= (~0x00000001); > + qc = ata_qc_from_tag(ap, tag); > + > + /* To be picked up by completion functions */ > + qc->ap->link.active_tag = tag; > + hsdevp->cmd_issued[tag] = SATA_DWC_CMD_ISSUED_NOT; > + > + /* Let libata/scsi layers handle error */ > + if (status& ATA_ERR) { > + dev_dbg(ap->dev, "%s ATA_ERR (0x%x)\n", __func__, > + status); > + sata_dwc_qc_complete(ap, qc, 1); > + handled = 1; > + goto DONE; > + } > + > + /* Process completed command */ > + dev_dbg(ap->dev, "%s NCQ command, protocol: %s\n", __func__, > + prot_2_txt(qc->tf.protocol)); > + if (ata_is_dma(qc->tf.protocol)) { > + hp->dma_interrupt_count++; > + if (hsdevp->dma_pending[tag] == \ > + SATA_DWC_DMA_PENDING_NONE) > + dev_warn(ap->dev, "%s: DMA not pending?\n", > + __func__); > + if ((hp->dma_interrupt_count) % 2 == 0) > + sata_dwc_dma_xfer_complete(ap, 1); > + } else { > + if (unlikely(sata_dwc_qc_complete(ap, qc, 1))) > + goto STILLBUSY; > + } > + continue; > + > +STILLBUSY: > + ap->stats.idle_irq++; > + dev_warn(ap->dev, "STILL BUSY IRQ ata%d: irq trap\n", > + ap->print_id); > + } /* while tag_mask */ > + > + /* > + * Check to see if any commands completed while we were processing our > + * initial set of completed commands (reading of status clears > + * interrupts, so we might miss a completed command interrupt if one > + * came in while we were processing --we read status as part of > + * processing a completed command). > + */ > + sactive2 = core_scr_read(SCR_ACTIVE); > + if (sactive2 != sactive) { > + dev_dbg(ap->dev, "More completed-sactive=0x%x sactive2=0x%x\n", > + sactive, sactive2); > + goto PROCESS; this appears to be a recipe for an infinite loop? > +/* > + * Function : sata_dwc_port_start > + * arguments : struct ata_ioports *port > + * Return value : returns 0 if success, error code otherwise > + * This function allocates the scatter gather LLI table for AHB DMA > + */ > +static int sata_dwc_port_start(struct ata_port *ap) > +{ > + int err = 0; > + struct sata_dwc_device *hsdev; > + struct sata_dwc_device_port *hsdevp = NULL; > + struct device *pdev; > + u32 sstatus; > + int i; > + > + hsdev = HSDEV_FROM_AP(ap); > + > + dev_dbg(ap->dev, "%s: port_no=%d\n", __func__, ap->port_no); > + > + hsdev->host = ap->host; > + pdev = ap->host->dev; > + if (!pdev) { > + dev_err(ap->dev, "%s: no ap->host->dev\n", __func__); > + err = -ENODEV; > + goto CLEANUP; > + } > + > + /* Allocate Port Struct */ > + hsdevp = kmalloc(sizeof(*hsdevp), GFP_KERNEL); > + if (!hsdevp) { > + dev_err(ap->dev, "%s: kmalloc failed for hsdevp\n", __func__); > + err = -ENOMEM; > + goto CLEANUP; > + } > + memset(hsdevp, 0, sizeof(*hsdevp)); use kzalloc() > + /* Clear any error bits before libata starts issuing commands */ > + clear_serror(); > + > + ap->private_data = hsdevp; > + > + /* Are we in Gen I or II */ > + sstatus = core_scr_read(SCR_STATUS); > + switch (SATA_DWC_SCR0_SPD_GET(sstatus)) { > + case 0x0: > + dev_info(ap->dev, "**** No negotiated speed (nothing attached?" > + ") ****\n"); > + break; > + case 0x1: > + dev_info(ap->dev, "**** GEN I speed rate negotiated ****\n"); > + break; > + case 0x2: > + dev_info(ap->dev, "**** GEN II speed rate negotiated ****\n"); > + break; > + } NAK, libata already prints this out > +/* > + * Function : sata_dwc_exec_command_by_tag > + * arguments : ata_port *ap, ata_taskfile *tf, u8 tag, u32 cmd_issued > + * Return value : None > + * This function keeps track of individual command tag ids and calls > + * ata_exec_command in libata > + */ > +static void sata_dwc_exec_command_by_tag(struct ata_port *ap, > + struct ata_taskfile *tf, > + u8 tag, u32 cmd_issued) > +{ > + > + struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap); > + > + dev_dbg(ap->dev, "%s cmd(0x%02x): %s tag=%d\n", __func__, tf->command, > + ata_cmd_2_txt(tf), tag); > + > + spin_lock(&ap->host->lock); > + hsdevp->cmd_issued[tag] = cmd_issued; > + spin_unlock(&ap->host->lock); either you need spin_lock_irqsave(), or you don't need the lock at all. investigate which. > +static void sata_dwc_qc_prep(struct ata_queued_cmd *qc) > +{ > + u32 sactive; > + u8 tag = qc->tag; > + > + if ((qc->dma_dir == DMA_NONE) || (qc->tf.protocol == ATA_PROT_PIO)) > + return; > + > +#ifdef DEBUG_NCQ > + if (qc->tag> 0) > + dev_info(qc->ap->dev, "%s: qc->tag=%d ap->active_tag=0x%08x\n", > + __func__, tag, qc->ap->link.active_tag); > +#endif > + > + if (ata_is_ncq(qc->tf.protocol)) { > + sactive = core_scr_read(SCR_ACTIVE); > + sactive |= (0x00000001<< tag); > + core_scr_write(SCR_ACTIVE, sactive); > + dev_dbg(qc->ap->dev, "%s: tag=%d ap->link.sactive = 0x%08x " > + "sactive=0x%08x\n", __func__, tag, qc->ap->link.sactive, > + sactive); > + } else { > + tag = 0; > + } > + > + sata_dwc_qc_prep_by_tag(qc, tag); qc_prep is for setting up DMA internally, not on the hardware. SActive should be twiddled in qc_issue. > +static struct scsi_host_template sata_dwc_sht = { > + ATA_NCQ_SHT(DRV_NAME), > + /* > + * test-only: Currently this driver doesn't handle NCQ > + * correctly. We enable NCQ but set the queue depth to a > + * max of 1. This will get fixed in in a future release. > + */ > + .sg_tablesize = LIBATA_MAX_PRD, > + .can_queue = ATA_DEF_QUEUE, /* ATA_MAX_QUEUE */ > + .dma_boundary = ATA_DMA_BOUNDARY, > +}; What is the problem with NCQ? It is better to submit a non-NCQ driver then, rather than a driver with lots of buggy, unused NCQ code. > +static const struct ata_port_info sata_dwc_port_info[] = { > + { > + .flags = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY | > + ATA_FLAG_MMIO | ATA_FLAG_NCQ, > + .pio_mask = 0x1f, /* pio 0-4 */ > + .udma_mask = ATA_UDMA6, > + .port_ops =&sata_dwc_ops, > + }, ditto... don't flag ATA_FLAG_NCQ if you note in the above comment that NCQ is broken -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/