Re: [PATCH] ARM: i.MX23: fix memory size calulcation

[Sascha Hauer <sha@pengutronix.de>]

On Fri, Sep 09, 2022 at 04:39:15PM +0200, Bastian Krause wrote:
> According to the i.MX233 Reference Manual (i.MX233RM, Rev. 4, 03 April
> 2009) section "14.1.1 AHB Address Ranges", the formula to calculate the
> DRAM memory size is:
> 
>   dram_memory_available = 2 * 2^col * 2^row * (# dram_devices) * (# banks_per_device)
> 
> The calulcation in barebox misses the first factor, so the result is
> only half as big as it should be.
> 
> On an iMX233 OLinuXino board the following errors can be observed:
> 
>   mmu: Critical Error: Can't request SDRAM region for ttb at 43fe4000
>   Error: Cannot request SDRAM region for stack
> 
> The faulty calulcation leads to 32 MB being detected (as seen in the
> output of `iomem`), although 64 MB should be available (as passed to
> barebox_arm_entry() in lowlevel code).
> 
> Fix the memory calculation by adding the missing factor 2.
> 
> Fixes: 7158c5987e6 ("ARM: i.MX23: Add memory size detection")
> Signed-off-by: Bastian Krause <bst@pengutronix.de>
> Signed-off-by: Jürgen Borleis <jbe@pengutronix.de>
> ---
>  arch/arm/mach-mxs/include/mach/imx23.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Applied to master, thanks

Sascha

> 
> diff --git a/arch/arm/mach-mxs/include/mach/imx23.h b/arch/arm/mach-mxs/include/mach/imx23.h
> index bdd3ae4407a..03eddabed0a 100644
> --- a/arch/arm/mach-mxs/include/mach/imx23.h
> +++ b/arch/arm/mach-mxs/include/mach/imx23.h
> @@ -25,7 +25,7 @@ static inline u32 imx23_get_memsize(void)
>  	cs0 = FIELD_GET(DRAM_CTL14_CS0_EN, ctl14);
>  	cs1 = FIELD_GET(DRAM_CTL14_CS1_EN, ctl14);
>  
> -	return (1 << columns) * (1 << rows) * banks * (cs0 + cs1);
> +	return 2 * (1 << columns) * (1 << rows) * banks * (cs0 + cs1);
>  }
>  
>  #endif /* __MACH_IMX23_H */
> -- 
> 2.30.2
> 
> 
> 

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