Messages in this thread | | | Date | Fri, 25 Sep 2015 14:05:52 +0100 | From | "Suzuki K. Poulose" <> | Subject | Re: [PATCH 07/22] arm64: Keep track of CPU feature registers |
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On 25/09/15 12:38, Dave P Martin wrote: > On Wed, Sep 16, 2015 at 03:21:05PM +0100, Suzuki K. Poulose wrote: >> From: "Suzuki K. Poulose" <suzuki.poulose@arm.com> >> >> This patch adds an infrastructure to keep track of the CPU feature >> registers on the system. For each register, the infrastructure keeps >> track of the system wide safe value of the feature bits. Also, tracks >> the which fields of a register should be matched strictly across all >> the CPUs on the system for the SANITY check infrastructure. >> >> The feature bits are classified as one of SCALAR_MIN, SCALAR_MAX and DISCRETE >> depending on the implication of the possible values. This information >> is used to decide the safe value for a feature. >> >> SCALAR_MIN - The smaller value is safer >> SCALAR_MAX - The bigger value is safer >> DISCRETE - We can't decide between the two, so a predefined safe_value is used. > > Can documentation of the meanings of these be added somewhere in the > relevant header or in Documentation?
Sure. They were part of the initial draft and eventually lost them over the reworks. I will add them back, since there is wider use of the information across the system, from what I started with(i.e, Userspace visibility).
Cheers Suzuki
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