[PATCH v5 0/4] ARM: shmobile: r8a7740/sh73a0 DT Cache Handling

Geert Uytterhoeven geert at linux-m68k.org
Wed Nov 25 00:45:20 PST 2015

Hi Simon,

On Wed, Nov 25, 2015 at 2:50 AM, Simon Horman <horms at verge.net.au> wrote:
> On Mon, Nov 23, 2015 at 02:55:58PM +0100, Geert Uytterhoeven wrote:
>> This patch series add minimal L1 and L2 cache descriptions to DT for
>> r8a7740 and sh73a0, and migrates the shmobile DT-based generic r8a7740
>> platform from calling l2x0_of_init() to the generic l2c OF
>> initialization.
>> Note that the conversion to the generic l2c OF initialization is not
>> done yet for sh73a0, as this initializes the L2 cache earlier, breaking
>> the (fragile) sh73a0 secondary CPU bringup code.
>> Also note that this conversion should be done on r8a7778, and r8a7779,
>> too.
> Based on your work I have prepared a DT patch for the r8a7779.

Thanks for following up.

> I don't think that a C patch is necessary, please correct me if I am wrong.

Yes you do!
Without machine_desc.l2x_aux_{val,mask}, the information in DT is not used.
Cfr. arch/arm/mach-shmobile/setup-r8a7740.c

> Regarding the r8a7778: My reading of the documentation is that although a
> pl310 L2 cache controller is present it is not available for use as there
> is no L2 cache memory present. For this reason I do not think any patches
> are required for the r8a7798.

I agree after consulting the datasheet.

>> Dependencies:
>>   - This series applies to renesas-devel-20151123-v4.4-rc2,
>>   - Patch 3 depends on patch 1,
>>   - Patch 4 depends on patch 3.
>> Given C code changesets depending on DT changesets in the same branch
>> are frowned upon, you may want to postpone patches 3 and 4 to v4.6.
>> Of course I'll sleep better if you just apply all 4 of them now ;-)
> I have queued up the DT changes for v4.5.
> And tentatively queued up the C changes for v4.6.

Thank you!



Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

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