| Message ID | 1336623449-7697-1-git-send-email-tqnguyen@apm.com |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
Hello. On 10-05-2012 8:17, Thang Q. Nguyen wrote: > Signed-off-by: Thang Q. Nguyen<tqnguyen@apm.com> > --- > drivers/ata/sata_dwc_460ex.c | 64 ++++++++++++++++++++++++++++++++++++++++-- > 1 files changed, 61 insertions(+), 3 deletions(-) > diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c > index 937aeb3..6175e01 100755 > --- a/drivers/ata/sata_dwc_460ex.c > +++ b/drivers/ata/sata_dwc_460ex.c [...] > @@ -1385,6 +1389,58 @@ static void sata_dwc_port_stop(struct ata_port *ap) > ap->private_data = NULL; > } > > +/** > + * sata_dwc_check_atapi_dma - Filter ATAPI cmds which are unsuitable for DMA. > + * @qc: queued command to check for chipset/DMA compatibility. > + * > + * The bmdma engines cannot handle speculative data sizes (bytecount > + * under/over flow). So only allow DMA for data transfer commands with > + * known data sizes. > + */ > +static int sata_dwc_check_atapi_dma(struct ata_queued_cmd *qc) > +{ [...] > + > + /* -45150 (FFFF4FA2) to -1 (FFFFFFFF) shall use PIO mode */ Sector numbers are unsigned entities. > + if (scmd->cmnd[0] == WRITE_10) { > + lba = (scmd->cmnd[2] << 24) | > + (scmd->cmnd[3] << 16) | > + (scmd->cmnd[4] << 8) | > + scmd->cmnd[5]; > + if (lba>= 0xFFFF4FA2) > + pio = 1; > + } > + /* > + * WORK AROUND: Fix DMA issue when blank CD/DVD disc in the drive > + * and user use the 'fdisk -l' command. No DMA data returned so > + * we can not complete the QC. The user shouldn't use 'fdisk' command on CD/DVD disks. On the other hand, he could use something like 'hdparm -t' od 'dd' with offset in which case I'm not sure this heuristics will work. > + */ > + else if (scmd->cmnd[0] == READ_10) { > + lba = (scmd->cmnd[2] << 24) | > + (scmd->cmnd[3] << 16) | > + (scmd->cmnd[4] << 8) | > + scmd->cmnd[5]; > + if (lba < 0x20) > + pio = 1; > + } > + } > + return pio; > +} > + > /* > * Function : sata_dwc_exec_command_by_tag > * arguments : ata_port *ap, ata_taskfile *tf, u8 tag, u32 cmd_issued WBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hello. On 10-05-2012 14:12, Thang Q. Nguyen wrote: > Thanks for quick response, > I do not mean user use fdisk command on CD/DVD. However, whenever using 'fdisk > -l' command, the system will access each first sector on each SCSI device > (including CD/DVD on it) and the DMA transfer on blank CD/DVD will not return > any data. Shouldn't the drive return error status in this case? > The timeout is detected and error handler will be called. But user may also run 'hdparm -t' or even 'dd' with offset on a drive. Have you tried your workaround with those? > Using PIO on some first sectors will avoid the issue. > Regards, > Thang Nguyen - MBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c index 937aeb3..6175e01 100755 --- a/drivers/ata/sata_dwc_460ex.c +++ b/drivers/ata/sata_dwc_460ex.c @@ -1035,7 +1035,8 @@ DRVSTILLBUSY: if ((host_pvt.dma_interrupt_count % 2) == 0) sata_dwc_dma_xfer_complete(ap, 1); - } else if (ata_is_pio(qc->tf.protocol)) { + } else if (ata_is_pio(qc->tf.protocol) || + ata_is_nodata(qc->tf.protocol)) { ata_sff_hsm_move(ap, qc, status, 0); handled = 1; goto DONE; @@ -1235,7 +1236,10 @@ static int sata_dwc_qc_complete(struct ata_port *ap, struct ata_queued_cmd *qc, & mask; host_pvt.sata_dwc_sactive_issued = (host_pvt.sata_dwc_sactive_issued) \ & mask; - ata_qc_complete(qc); + if (ata_is_atapi(qc->tf.protocol)) + ata_sff_hsm_move(ap, qc, status, 0); + else + ata_qc_complete(qc); return 0; } @@ -1385,6 +1389,58 @@ static void sata_dwc_port_stop(struct ata_port *ap) ap->private_data = NULL; } +/** + * sata_dwc_check_atapi_dma - Filter ATAPI cmds which are unsuitable for DMA. + * @qc: queued command to check for chipset/DMA compatibility. + * + * The bmdma engines cannot handle speculative data sizes (bytecount + * under/over flow). So only allow DMA for data transfer commands with + * known data sizes. + */ +static int sata_dwc_check_atapi_dma(struct ata_queued_cmd *qc) +{ + struct scsi_cmnd *scmd = qc->scsicmd; + int pio = 1; /* atapi dma off by default */ + unsigned int lba; + + if (scmd) { + switch (scmd->cmnd[0]) { + case WRITE_6: + case WRITE_10: + case WRITE_12: + case READ_6: + case READ_10: + case READ_12: + pio = 0; /* DMA is safe */ + break; + } + + /* -45150 (FFFF4FA2) to -1 (FFFFFFFF) shall use PIO mode */ + if (scmd->cmnd[0] == WRITE_10) { + lba = (scmd->cmnd[2] << 24) | + (scmd->cmnd[3] << 16) | + (scmd->cmnd[4] << 8) | + scmd->cmnd[5]; + if (lba >= 0xFFFF4FA2) + pio = 1; + } + /* + * WORK AROUND: Fix DMA issue when blank CD/DVD disc in the drive + * and user use the 'fdisk -l' command. No DMA data returned so + * we can not complete the QC. + */ + else if (scmd->cmnd[0] == READ_10) { + lba = (scmd->cmnd[2] << 24) | + (scmd->cmnd[3] << 16) | + (scmd->cmnd[4] << 8) | + scmd->cmnd[5]; + if (lba < 0x20) + pio = 1; + } + } + return pio; +} + /* * Function : sata_dwc_exec_command_by_tag * arguments : ata_port *ap, ata_taskfile *tf, u8 tag, u32 cmd_issued @@ -1572,7 +1628,8 @@ static unsigned int sata_dwc_qc_issue(struct ata_queued_cmd *qc) static void sata_dwc_qc_prep(struct ata_queued_cmd *qc) { - if ((qc->dma_dir == DMA_NONE) || (qc->tf.protocol == ATA_PROT_PIO)) + if ((qc->dma_dir == DMA_NONE) || (qc->tf.protocol == ATA_PROT_PIO) || + (qc->tf.protocol == ATAPI_PROT_PIO)) return; #ifdef DEBUG_NCQ @@ -1641,6 +1698,7 @@ static struct ata_port_operations sata_dwc_ops = { .port_start = sata_dwc_port_start, .port_stop = sata_dwc_port_stop, + .check_atapi_dma = sata_dwc_check_atapi_dma, .bmdma_setup = sata_dwc_bmdma_setup, .bmdma_start = sata_dwc_bmdma_start, };
Signed-off-by: Thang Q. Nguyen <tqnguyen@apm.com> --- drivers/ata/sata_dwc_460ex.c | 64 ++++++++++++++++++++++++++++++++++++++++-- 1 files changed, 61 insertions(+), 3 deletions(-)