[lkml]   [2022]   [May]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH v3 04/23] dt-bindings: ata: sata: Extend number of SATA ports
On Thu, 12 May 2022 02:17:51 +0300, Serge Semin wrote:
> The denoted in the description upper limit only concerns the Port
> Multipliers, but not the actual SATA ports. It's an external device
> attached to a SATA port in order to access more than one SATA-drive. So
> when it's attached to a SATA port it just extends the port capability
> while the number of actual SATA ports stays the same. For instance on AHCI
> controllers the number of actual ports is determined by the CAP.NP field
> and the PI (Ports Implemented) register. AFAICS in general the maximum
> number of SATA ports depends on the particular controller implementation.
> Generic AHCI controller can't have more than 32 ports (since CAP.NP is of
> 5 bits wide and PI register is 32-bits size), while DWC AHCI SATA
> controller can't be configured with more than 8 ports activated. So let's
> discard the SATA ports reg-property restrictions and just make sure that
> it consists of a single reg-item.
> Signed-off-by: Serge Semin <>
> ---
> Changelog v2:
> - Add comma and replace "channel" with "SATA port" in the reg property
> description (@Damien).
> ---
> Documentation/devicetree/bindings/ata/sata-common.yaml | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)

Reviewed-by: Rob Herring <>

 \ /
  Last update: 2022-05-17 21:16    [W:0.483 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site