The mainboard MSI E350DM-E33 is advertised with 6 SATA ports. As it turns out, two of them seem to be driven by on-board SATA<->PATA converters. If a disk drive is connected to one of them kernel uses UDMA/33 mode due to cable detection: [ 34.550823] scsi4 : pata_atiixp [ 34.555517] scsi5 : pata_atiixp [ 34.555942] ata5: PATA max UDMA/100 cmd 0x1f0 ctl 0x3f6 bmdma 0xf100 irq 14 [ 34.555948] ata6: PATA max UDMA/100 cmd 0x170 ctl 0x376 bmdma 0xf108 irq 15 ... [ 35.040799] ata5.00: ATA-8: WDC WD20EADS-00R6B0, 01.00A01, max UDMA/133 [ 35.040806] ata5.00: 3907029168 sectors, multi 16: LBA48 NCQ (depth 0/32) [ 35.040817] ata5.00: limited to UDMA/33 due to 40-wire cable [ 35.049166] ata5.00: configured for UDMA/33 [ 35.049402] scsi 4:0:0:0: Direct-Access ATA WDC WD20EADS-00R 01.0 PQ: 0 ANSI: 5 This patch forces "short cable" mode on this board, as it seems clear that the on-board SATA<->PATA "cable" is short. With this patch the disk is configured for UDMA/100: [ 5.976756] ata5.00: ATA-8: WDC WD20EADS-00R6B0, 01.00A01, max UDMA/133 [ 5.996434] ata5.00: 3907029168 sectors, multi 16: LBA48 NCQ (depth 0/32) [ 6.024787] ata5.00: configured for UDMA/100 Testing revealed no transfer issues. Signed-off-by: Arnd Hannemann <arnd@xxxxxxxxxx> --- drivers/ata/pata_atiixp.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/ata/pata_atiixp.c b/drivers/ata/pata_atiixp.c index 361c75c..24e5105 100644 --- a/drivers/ata/pata_atiixp.c +++ b/drivers/ata/pata_atiixp.c @@ -20,6 +20,7 @@ #include <linux/delay.h> #include <scsi/scsi_host.h> #include <linux/libata.h> +#include <linux/dmi.h> #define DRV_NAME "pata_atiixp" #define DRV_VERSION "0.4.6" @@ -33,11 +34,26 @@ enum { ATIIXP_IDE_UDMA_MODE = 0x56 }; +static const struct dmi_system_id attixp_cable_override_dmi_table[] = { + { + /* Board has onboard PATA<->SATA converters */ + .ident = "MSI E350DM-E33", + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "MSI"), + DMI_MATCH(DMI_BOARD_NAME, "E350DM-E33(MS-7720)"), + }, + }, + { } +}; + static int atiixp_cable_detect(struct ata_port *ap) { struct pci_dev *pdev = to_pci_dev(ap->host->dev); u8 udma; + if (dmi_check_system(attixp_cable_override_dmi_table)) + return ATA_CBL_PATA40_SHORT; + /* Hack from drivers/ide/pci. Really we want to know how to do the raw detection not play follow the bios mode guess */ pci_read_config_byte(pdev, ATIIXP_IDE_UDMA_MODE + ap->port_no, &udma); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html