On Apr 10, 2015, at 5:05 AM, Catalin Marinas <catalin.marinas@xxxxxxx> 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. > > -- > Catalin Does it matter? I’ve always felt the kernel was a place of inclusion. Qualcomm choose for whatever reason to not use PSCI or spin table. You don’t like it, I might not like it, but it is what it is. - 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
