Subject: [PATCH v2] ARM: imx: gpc: Initialize all power domains

From: [email-masked] (Shawn Guo)
Date: Fri, 21 Oct 2016 11:11:16 +0800

On Thu, Oct 20, 2016 at 11:28:29PM -0200, Fabio Estevam wrote:
> From: Fabio Estevam <[email-masked]>
> 
> Since commit 0159ec670763dd ("PM / Domains: Verify the PM domain is present
> when adding a provider") the following regression is observed on imx6:
> 
> imx-gpc: probe of 20dc000.gpc failed with error -22
> 
> The imx-gpc driver probe failure causes several issues such as:
> 
> - When booting a kernel built with multi_v7_defconfig a kernel crash is
> seen.
> 
> - When booting a kernel built with imx_v6_v7_defconfig the Etnaviv GPU
> driver is not loaded due to the lack of power domains.
> 
> The gpc probe fails because of_genpd_add_provider_onecell() now checks
> if all the domains are initialized via pm_genpd_present() function
> and it fails because not all the power domains are initialized.

Thanks for the update.  Now we understand that this is a regression
caused by power domain core change.  But my question on why kernel
crashes with multi_v7_defconfig but not with imx_v6_v7_defconfig stays
unanswered.

Shawn

> 
> In order to fix this error, initialize all the power domains from
> imx_gpc_domains[], not only the imx6q_pu_domain.base one.
> 
> Reported-by: Olof's autobooter <[email-masked]>
> Signed-off-by: Fabio Estevam <[email-masked]>
> ---
>  arch/arm/mach-imx/gpc.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-imx/gpc.c b/arch/arm/mach-imx/gpc.c
> index 0df062d..d0463e9 100644
> --- a/arch/arm/mach-imx/gpc.c
> +++ b/arch/arm/mach-imx/gpc.c
> @@ -430,7 +430,8 @@ static int imx_gpc_genpd_init(struct device *dev, struct regulator *pu_reg)
>  	if (!IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS))
>  		return 0;
>  
> -	pm_genpd_init(&imx6q_pu_domain.base, NULL, false);
> +	for (i = 0; i < ARRAY_SIZE(imx_gpc_domains); i++)
> +		pm_genpd_init(imx_gpc_domains[i], NULL, false);
>  	return of_genpd_add_provider_onecell(dev->of_node,
>  					     &imx_gpc_onecell_data);
>  
> -- 
> 2.7.4
> 
> 
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