72aad489f9
The {dma|pio}_mode sysfs files are incorrectly documented as having a
list of the supported DMA/PIO transfer modes, while the corresponding
fields of the *struct* ata_device hold the transfer mode IDs, not masks.
To match these docs, the {dma|pio}_mode (and even xfer_mode!) sysfs
files are handled by the ata_bitfield_name_match() macro which leads to
reading such kind of nonsense from them:
$ cat /sys/class/ata_device/dev3.0/pio_mode
XFER_UDMA_7, XFER_UDMA_6, XFER_UDMA_5, XFER_UDMA_4, XFER_MW_DMA_4,
XFER_PIO_6, XFER_PIO_5, XFER_PIO_4, XFER_PIO_3, XFER_PIO_2, XFER_PIO_1,
XFER_PIO_0
Using the correct ata_bitfield_name_search() macro fixes that:
$ cat /sys/class/ata_device/dev3.0/pio_mode
XFER_PIO_4
While fixing the file documentation, somewhat reword the {dma|pio}_mode
file doc and add a note about being mostly useful for PATA devices to
the xfer_mode file doc...
Fixes: d9027470b8 ("[libata] Add ATA transport class")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
4.3 KiB
What: /sys/class/ata_* Description: Provide a place in sysfs for storing the ATA topology of the system. This allows retrieving various information about ATA objects.
Files under /sys/class/ata_port
For each port, a directory ataX is created where X is the ata_port_id of the port. The device parent is the ata host device.
What: /sys/class/ata_port/ataX/nr_pmp_links What: /sys/class/ata_port/ataX/idle_irq Date: May, 2010 KernelVersion: v2.6.37 Contact: Gwendal Grignou gwendal@chromium.org Description: nr_pmp_links: (RO) If a SATA Port Multiplier (PM) is connected, the number of links behind it.
idle_irq: (RO) Number of IRQ received by the port while
idle [some ata HBA only].
What: /sys/class/ata_port/ataX/port_no Date: May, 2013 KernelVersion: v3.11 Contact: Gwendal Grignou gwendal@chromium.org Description: (RO) Host local port number. While registering host controller, port numbers are tracked based upon number of ports available on the controller. This attribute is needed by udev for composing persistent links in /dev/disk/by-path.
Files under /sys/class/ata_link
Behind each port, there is a ata_link. If there is a SATA PM in the topology, 15 ata_link objects are created.
If a link is behind a port, the directory name is linkX, where X is ata_port_id of the port. If a link is behind a PM, its name is linkX.Y where X is ata_port_id of the parent port and Y the PM port.
What: /sys/class/ata_link/linkX[.Y]/hw_sata_spd_limit What: /sys/class/ata_link/linkX[.Y]/sata_spd_limit What: /sys/class/ata_link/linkX[.Y]/sata_spd Date: May, 2010 KernelVersion: v2.6.37 Contact: Gwendal Grignou gwendal@chromium.org Description: hw_sata_spd_limit: (RO) Maximum speed supported by the connected SATA device.
sata_spd_limit: (RO) Maximum speed imposed by libata.
sata_spd: (RO) Current speed of the link
eg. 1.5, 3 Gbps etc.
Files under /sys/class/ata_device
Behind each link, up to two ata devices are created. The name of the directory is devX[.Y].Z where:
- X is ata_port_id of the port where the device is connected,
- Y the port of the PM if any, and
- Z the device id: for PATA, there is usually 2 devices [0,1], only 1 for SATA.
What: /sys/class/ata_device/devX[.Y].Z/spdn_cnt What: /sys/class/ata_device/devX[.Y].Z/gscr What: /sys/class/ata_device/devX[.Y].Z/ering What: /sys/class/ata_device/devX[.Y].Z/id What: /sys/class/ata_device/devX[.Y].Z/pio_mode What: /sys/class/ata_device/devX[.Y].Z/xfer_mode What: /sys/class/ata_device/devX[.Y].Z/dma_mode What: /sys/class/ata_device/devX[.Y].Z/class Date: May, 2010 KernelVersion: v2.6.37 Contact: Gwendal Grignou gwendal@chromium.org Description: spdn_cnt: (RO) Number of times libata decided to lower the speed of link due to errors.
gscr: (RO) Cached result of the dump of PM GSCR
register. Valid registers are:
0: SATA_PMP_GSCR_PROD_ID,
1: SATA_PMP_GSCR_REV,
2: SATA_PMP_GSCR_PORT_INFO,
32: SATA_PMP_GSCR_ERROR,
33: SATA_PMP_GSCR_ERROR_EN,
64: SATA_PMP_GSCR_FEAT,
96: SATA_PMP_GSCR_FEAT_EN,
130: SATA_PMP_GSCR_SII_GPIO
Only valid if the device is a PM.
ering: (RO) Formatted output of the error ring of the
device.
id: (RO) Cached result of IDENTIFY command, as
described in ATA8 7.16 and 7.17. Only valid if
the device is not a PM.
pio_mode: (RO) PIO transfer mode used by the device.
Mostly used by PATA devices.
xfer_mode: (RO) Current transfer mode. Mostly used by
PATA devices.
dma_mode: (RO) DMA transfer mode used by the device.
Mostly used by PATA devices.
class: (RO) Device class. Can be "ata" for disk,
"atapi" for packet device, "pmp" for PM, or
"none" if no device was found behind the link.
What: /sys/class/ata_device/devX[.Y].Z/trim Date: May, 2015 KernelVersion: v4.10 Contact: Gwendal Grignou gwendal@chromium.org Description: (RO) Shows the DSM TRIM mode currently used by the device. Valid values are:
unsupported: Drive does not support DSM TRIM
unqueued: Drive supports unqueued DSM TRIM only
queued: Drive supports queued DSM TRIM
forced_unqueued: Drive's queued DSM support is known to
be buggy and only unqueued TRIM commands
are sent