Re: [PATCH] regulator: ti-abb: Add support for interleaved LDO registers

From: Nishanth Menon
Date: Tue Jan 21 2014 - 15:06:37 EST


On 01/21/2014 12:55 PM, Mark Brown wrote:
> On Thu, Jan 16, 2014 at 01:32:30PM -0600, Nishanth Menon wrote:
>
>> - abb->base = devm_ioremap_resource(dev, res);
>
>> + abb->base = devm_ioremap_nocache(dev, res->start, resource_size(res));
>
> devm_ioremap_resouce() should do the right thing if the memory region is
> marked as uncacheable (with IORESOURCE_CACHEABLE not set). Since I
> can't see the OF code actually setting that flag on the resources unless
> I'm missing something this change isn't needed?
>
Without this change, on DRA7 I get:
[ 0.579500] abb_mpu: 1060 <--> 1210 mV
[ 0.580321] abb_ivahd: 1055 <--> 1250 mV
[ 0.580583] ti_abb 4ae07e20.regulator-abb-dspeve: can't request
region for resource [mem 0x4ae07e20-0x4ae07e2f]
[ 0.580610] ti_abb: probe of 4ae07e20.regulator-abb-dspeve failed
with error -16
[ 0.581216] abb_gpu: 1090 <--> 1280 mV

with the change in the patch, I get:
[ 0.589750] abb_mpu: 1060 <--> 1210 mV
[ 0.590522] abb_ivahd: 1055 <--> 1250 mV
[ 0.591331] abb_dspeve: 1055 <--> 1250 mV
[ 0.592097] abb_gpu: 1090 <--> 1280 mV

reference dts:
https://github.com/nmenon/linux-2.6-playground/blob/abb-rev-v3.14-rc1-vnext-20140121/arch/arm/boot/dts/dra7.dtsi#L562
--
Regards,
Nishanth Menon
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