On Mon, Oct 28, 2013 at 8:12 AM, Kukjin Kim <kgene....@samsung.com> wrote: > On 10/28/13 08:15, Olof Johansson wrote: >> >> On Sun, Oct 27, 2013 at 10:36 PM, Jingoo Han<jg1....@samsung.com> wrote: >>> >>> On Monday, October 28, 2013 1:52 PM, Olof Johansson wrote: >>>> >>>> On Wed, Sep 4, 2013 at 11:08 PM, Jingoo Han<jg1....@samsung.com> wrote: >>>>> >>>>> Disable PCIe for SD5v1 board, because there is no PCIe slot >>>>> on SD5v1 board. >>>>> >>>>> Signed-off-by: Jingoo Han<jg1....@samsung.com> >>>>> --- >>>>> Tested on SD5v1 board. >>>>> >>>>> arch/arm/boot/dts/exynos5440-sd5v1.dts | 7 +++++++ >>>>> 1 file changed, 7 insertions(+) >>>>> >>>>> diff --git a/arch/arm/boot/dts/exynos5440-sd5v1.dts >>>>> b/arch/arm/boot/dts/exynos5440-sd5v1.dts >>>>> index 5b22508..78a239d 100644 >>>>> --- a/arch/arm/boot/dts/exynos5440-sd5v1.dts >>>>> +++ b/arch/arm/boot/dts/exynos5440-sd5v1.dts >>>>> @@ -36,4 +36,11 @@ >>>>> status = "disabled"; >>>>> }; >>>>> >>>>> + pcie@290000 { >>>>> + status = "disabled"; >>>>> + }; >>>>> + >>>>> + pcie@2a0000 { >>>>> + status = "disabled"; >>>>> + }; >>>>> }; >>>> >>>> >>>> Usually IP blocks like these are always left disabled in the dtsi, and >>>> explicitly _enabled_ in the DTS on boards that make use of that part >>>> of the chip. >>>> So the real solution here should be to move the disabling to the 5440 >>>> .dtsi instead. >>> >>> >>> OK, right. >>> Thank you for your guidance. >>> >>> Then, do you mean the following? >>> If it is right, I will send the v2 patch. >> >> >> Yes, exactly! >> > > Hmm...I thought both ways (#1 disabling something in soc dt, enabling in > board dt if required, #2 enabling in soc dt, disabling in board dt if > required) are possible but I have no strong objection with your suggestion. > In addition, just one way is more clear to us :) > > OK, I will keep the way for Samsung stuff.
It varies, in some cases it makes sense to make the default enabled and just disable where needed, for example for entirely on-chip IP blocks. For things like PCI-e, where different board manufacturers might choose to use it or not, it seems that keeping disabled by default is sensible. -Olof -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html