CONFIG_PL310_ERRATA_769419 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

PL310 errata: no automatic Store Buffer drain

configname: CONFIG_PL310_ERRATA_769419

Linux Kernel Configuration
└─>System Type
└─>PL310 errata: no automatic Store Buffer drain
In linux kernel since version 2.6.32.6 (release Date: 2010-01-25)  
On revisions of the PL310 prior to r3p2, the Store Buffer does
not automatically drain. This can cause normal, non-cacheable
writes to be retained when the memory system is idle, leading
to suboptimal I/O performance for drivers using coherent DMA.
This option adds a write barrier to the cpu_idle loop so that,
on systems with an outer cache, the store buffer is drained
explicitly.