Re:[PATCH] powerpc/Kconfig: Make FSL_85XX_CACHE_SRAM configurable

[王文虎]

From: Scott Wood <oss at buserror.net>
Date: 2020-01-21 11:25:25
To:  wangwenhu <wenhu.pku at gmail.com>,Kumar Gala <galak at kernel.crashing.org>,Benjamin Herrenschmidt <benh at kernel.crashing.org>,Paul Mackerras <paulus at samba.org>,Michael Ellerman <mpe at ellerman.id.au>,linuxppc-dev at lists.ozlabs.org,linux-kernel at vger.kernel.org
Cc:  trivial at kernel.org,wenhu.wang at vivo.com,Rai Harninder <harninder.rai at nxp.com>
Subject: Re: [PATCH] powerpc/Kconfig: Make FSL_85XX_CACHE_SRAM configurable>On Mon, 2020-01-20 at 06:43 -0800, wangwenhu wrote:
>> From: wangwenhu <wenhu.wang at vivo.com>
>> 
>> When generating .config file with menuconfig on Freescale BOOKE
>> SOC, FSL_85XX_CACHE_SRAM is not configurable for the lack of
>> description in the Kconfig field, which makes it impossible
>> to support L2Cache-Sram driver. Add a description to make it
>> configurable.
>> 
>> Signed-off-by: wangwenhu <wenhu.wang at vivo.com>
>
>The intent was that drivers using the SRAM API would select the symbol.  What
>is the use case for selecting it manually?
>

With a repository of multiple products(meaning different defconfigs) and multiple
developers, the Kconfigs of the Kernel Source Tree change frequently. So the "make menuconfig"
process is needed for defconfigs' re-generating or updating for the complexity of dependencies
between different features defined in the Kconfigs.

>Since this code was added almost ten years ago and there are still no (in-
>tree?) users of the API, we should just remove the sram code (unless this
>prods someone to submit such a user very soon).
>

Yes, pretty long a time. But we DO really use the API now for PPCE500/Freescale SoC.
Like sometimes we need to reset the whole RAM, then the L2-Cache would be used as
SRAM for backup using. Since it is useful for us now, a re-consideration is recommanded.

>-Scott
>
>

--
Wenhu
vivo