Re: [PATCH v4 5/6] ARM: zynq: Add OCM controller driver

[Linus Walleij]

On Thu, Nov 27, 2014 at 2:57 PM, Michal Simek <michal.simek@xxxxxxxxxx> wrote:
> On 11/27/2014 02:20 PM, Linus Walleij wrote:
>> On Fri, Nov 14, 2014 at 11:52 AM, Michal Simek <michal.simek@xxxxxxxxxx> wrote:

>> (...)
>>> +       zynq_ocmc->pool = devm_gen_pool_create(&pdev->dev,
>>> +                                              ilog2(ZYNQ_OCMC_GRANULARITY),
>>> +                                              -1);
>>
>> Do this:
>>
>> #include <linux/sizes.h>
>>
>> zynq_ocmc->pool = devm_gen_pool_create(&pdev->dev,
>>                                        ilog2(SZ_64K),
>>                                        -1);
>>
>> And get rid of the #define for ZYNQ_OCMC_GRANULARITY
>
> ilog2 from 32 is different to ilog2 from ilog2 from 0x10000.

Bah I misread the code, forget this comment.

Maybe it's more like I wanted

+#define ZYNQ_OCMC_BLOCK_SIZE   0x10000

To be replaced with SZ_64K

But it's a petty detail anyway.

> Do you have any opinion regarding calling zynq_slcr_get_ocm_config()?
>
> Is it better to expose slcr this interface to drivers?
> Or use regmap and read this value directly?

Depends on what provides that call. The pattern I usually follow
is to expose the mixed-registers range as a syscon device
using drivers/mfd/syscon.c and then use one of the methods from
<linux/mfd/syscon.h> to look up a reference to the regmap and
use it to access misc registers.

> Also I do read for CONFIG_SMP case jump trampoline size - maybe
> you can have better idea how this can be done.

No I have no clue about that... :(

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