• Serge Semin's avatar
    dt-bindings: ata: sata: Extend number of SATA ports · 388f08ec
    Serge Semin authored
    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: default avatarSerge Semin <Sergey.Semin@baikalelectronics.ru>
    Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
    Reviewed-by: default avatarRob Herring <robh@kernel.org>
    Signed-off-by: default avatarDamien Le Moal <damien.lemoal@opensource.wdc.com>
    388f08ec
sata-common.yaml 1.47 KB