> On Apr 14, 2015, at 11:36 AM, Mark Rutland <mark.rutland@xxxxxxx> wrote: > > On Fri, Apr 10, 2015 at 11:05:29AM +0100, Catalin Marinas wrote: >> On Thu, Apr 09, 2015 at 12:37:06PM -0500, Kumar Gala wrote: >>> This patch set adds support for SMP boot on the MSM8x16 family of Qualcomm SoCs. >>> >>> To support SMP on the MSM8x16 SoCs we need to add ARMv8/64-bit SCM interfaces to >>> setup the boot/release addresses for the secondary CPUs. In addition we need >>> a uniquie set of cpu ops. I'm aware the desired methods for booting secondary >>> CPUs is either via spintable or PSCI. However, these SoCs are shipping with a >>> firmware that does not support those methods. >> >> And the reason is? Some guesses: >> >> a) QC doesn't think boot interface (and cpuidle) standardisation is >> worth the effort (to put it nicely) >> b) The hardware was available before we even mentioned PSCI >> c) PSCI is not suitable for the QC's SCM interface >> d) Any combination of the above >> >> I strongly suspect it's point (a). Should we expect future QC hardware >> to do the same? >> >> You could argue the reason was (b), though we've been discussing PSCI >> for at least two years and, according to QC press releases, MSM8916 >> started sampling in 2014. >> >> The only valid reason is (c) and if that's the case, I would expect a >> proposal for a new firmware interface protocol (it could be PSCI-based), >> well documented, that can be shared with others that may encounter the >> same shortcomings. > > There's no need to even fork PSCI. The PSCI specification will evolve > over time as vendors request changes and we try to accomodate them. > > If there's something that PSCI doesn't do that you need it to, contact > ARM. Other vendors already have. But what is someone to do between the period of getting PSCI spec updated and needing to ship a product with firmware? The take still sounds like if you don’t implement an exact version of PSCI you are screwed from being supported in the upstream ARM64 kernel. - k -- Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html