linux-kernel - Re: [PATCH] ARM: exynos_defconfig: Enable big.LITTLE CPUidle support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 29 Aug 2015 18:01:39 +0900
From:	Krzysztof Kozlowski <k.kozlowski@...sung.com>
To:	Javier Martinez Canillas <javier@....samsung.com>,
	linux-kernel@...r.kernel.org
Cc:	Kukjin Kim <kgene@...nel.org>, Thierry Reding <treding@...dia.com>,
	Anand Moon <linux.amoon@...il.com>,
	Russell King <linux@....linux.org.uk>,
	linux-samsung-soc@...r.kernel.org,
	Sjoerd Simons <sjoerd.simons@...labora.co.uk>,
	Lukasz Majewski <l.majewski@...sung.com>,
	linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH] ARM: exynos_defconfig: Enable big.LITTLE CPUidle support

W dniu 28.08.2015 o 17:16, Javier Martinez Canillas pisze:
> Some Exynos big.LITTLE boards (i.e: Exynos5420 and Exynos5800 based
> Chromebooks) have proper firmware that allow the big.LITTLE CPUidle
> driver to work correctly, so enable support for this.
> 
> Signed-off-by: Javier Martinez Canillas <javier@....samsung.com>
> 
> ---
> Kukjin and Krzysztof,
> 
> As you know there are other boards like the Exynos5422 based Odroid XU{3,4}
> whose firmware is broken due leaving CCI in secure mode which means that the
> kernel MCPM support can't properly manage CCI.
> 
> So if you pick this patch, it should be tested in kernelci before appearing
> in linux-next to prevent any boot issues.
> 
> But if that happens, I believe that is better to do a fix / workaround in
> those broken platforms since nothing prevents users to enable this option
> anyways. For example the CCI device node could be disabled in the DTS.
> 
>  arch/arm/configs/exynos_defconfig | 1 +
>  1 file changed, 1 insertion(+)

On Odroid XU3L (next-20150828, Hardkernel u-boot) boot hangs just after:

[    2.568650] dwmmc_exynos 12200000.mmc: num-slots property not found,
assuming 1 slot is available

... so no. NACK :). First the boards, firmware, bootloader or kernel
code have to be fixed.

Best regards,
Krzysztof

> 
> diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig
> index 729e2fae3e58..228ee945b8ed 100644
> --- a/arch/arm/configs/exynos_defconfig
> +++ b/arch/arm/configs/exynos_defconfig
> @@ -30,6 +30,7 @@ CONFIG_CPU_FREQ=y
>  CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
>  CONFIG_CPUFREQ_DT=y
>  CONFIG_CPU_IDLE=y
> +CONFIG_ARM_BIG_LITTLE_CPUIDLE=y
>  CONFIG_ARM_EXYNOS_CPUIDLE=y
>  CONFIG_VFP=y
>  CONFIG_NEON=y
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/