Message ID | 1520425514-205565-2-git-send-email-john.garry@huawei.com (mailing list archive) |
---|---|
State | Accepted |
Headers | show |
On Wed, Mar 07, 2018 at 08:25:05PM +0800, John Garry wrote: > From: Xiaofei Tan <tanxiaofei@huawei.com> > > For some new boards with hip07 chipset we are required to > set PHY config registers differently. The hw property which > determines how to set these registers is in the PHY signal > attenuation readings. > > This patch add an devicetree property, "hisilicon,signal-attenuation", > which is used to describe the signal attenuation of an board. > > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Mark Rutland <mark.rutland@arm.com> > Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> > Signed-off-by: John Garry <john.garry@huawei.com> > --- > Documentation/devicetree/bindings/scsi/hisilicon-sas.txt | 7 +++++++ > 1 file changed, 7 insertions(+) Reviewed-by: Rob Herring <robh@kernel.org>
diff --git a/Documentation/devicetree/bindings/scsi/hisilicon-sas.txt b/Documentation/devicetree/bindings/scsi/hisilicon-sas.txt index df3bef7..8c6659e 100644 --- a/Documentation/devicetree/bindings/scsi/hisilicon-sas.txt +++ b/Documentation/devicetree/bindings/scsi/hisilicon-sas.txt @@ -53,6 +53,13 @@ Main node required properties: Optional main node properties: - hip06-sas-v2-quirk-amt : when set, indicates that the v2 controller has the "am-max-transmissions" limitation. + - hisilicon,signal-attenuation : array of 3 32-bit values, containing de-emphasis, + preshoot, and boost attenuation readings for the board. They + are used to describe the signal attenuation of the board. These + values' range is 7600 to 12400, and used to represent -24dB to + 24dB. + The formula is "y = (x-10000)/10000". For example, 10478 + means 4.78dB. Example: sas0: sas@c1000000 {