Re: [RESEND PATCH v3 1/2] drivers: amba: Updates to component identification for driver matching.

From: Suzuki K Poulose
Date: Fri Jan 11 2019 - 06:43:46 EST


Hi Mike,

On 18/12/2018 21:59, Mike Leach wrote:
The CoreSight specification (ARM IHI 0029E), updates the ID register
requirements for components on an AMBA bus, to cover both traditional
ARM Primecell type devices, and newer CoreSight and other components.

The Peripheral ID (PID) / Component ID (CID) pair is extended in certain
cases to uniquely identify components. CoreSight components related to
a single function can share Peripheral ID values, and must be further
identified using a Unique Component Identifier (UCI). e.g. the ETM, CTI,
PMU and Debug hardware of the A35 all share the same PID.

Bits 15:12 of the CID are defined to be the device class.
Class 0xF remains for PrimeCell and legacy components.
Class 0x9 defines the component as CoreSight (CORESIGHT_CID above)
Class 0x0, 0x1, 0xB, 0xE define components that do not have driver support
at present.
Class 0x2-0x8,0xA and 0xD-0xD are presently reserved.

The specification futher defines which classes of device use the standard
CID/PID pair, and when additional ID registers are required.

The patches provide an update of amba_device and matching code to handle
the additional registers required for the Class 0x9 (CoreSight) UCI.
The *data pointer in the amba_id is used by the driver to provide extended
ID register values for matching.

CoreSight components where PID/CID pair is currently sufficient for
unique identification need not provide this additional information.

Signed-off-by: Mike Leach <mike.leach@xxxxxxxxxx>
Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>

Looks like you missed my Reviewed tags on the previous version. Anyways,

Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>