Re: [PATCH v7 01/10] x86/cpufeatures: Add support for L3 Smart Data Cache Injection Allocation Enforcement

[Reinette Chatre]

Hi Babu,

On 7/10/25 10:16 AM, Babu Moger wrote:
> Smart Data Cache Injection (SDCI) is a mechanism that enables direct
> insertion of data from I/O devices into the L3 cache. By directly caching
> data from I/O devices rather than first storing the I/O data in DRAM,
> SDCI reduces demands on DRAM bandwidth and reduces latency to the processor
> consuming the I/O data.
> 
> The SDCIAE (SDCI Allocation Enforcement) PQE feature allows system software
> to control the portion of the L3 cache used for SDCI.
> 
> When enabled, SDCIAE forces all SDCI lines to be placed into the L3 cache
> partitions identified by the highest-supported L3_MASK_n register, where n
> is the maximum supported CLOSID.
> 
> Add CPUID feature bit that can be used to configure SDCIAE.
> 
> The feature details are documented in APM listed below [1].
> [1] AMD64 Architecture Programmer's Manual Volume 2: System Programming
> Publication # 24593 Revision 3.41 section 19.4.7 L3 Smart Data Cache
> Injection Allocation Enforcement (SDCIAE)
> 
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
> Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
> ---

Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>

Reinette