[lkml]   [2013]   [Jun]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [Arm-netbook] getting allwinner SoC support upstream (was Re: Uploading linux (3.9.4-1))
On Wed, Jun 5, 2013 at 7:26 PM, luke.leighton <> wrote:
> On Thu, Jun 6, 2013 at 12:07 AM, <> wrote:
>> On Wed, Jun 5, 2013 at 6:47 PM, luke.leighton <> wrote:
>>> On Wed, Jun 5, 2013 at 10:59 PM, Henrik Nordström
>>> <> wrote:
>>>>> .... and then there's the boot0 and boot1 loaders, these *do* have
>>>> no, these are not tiny. boot0 is 24KB to fit the initial embedded SRAM
>>>> (not cache), but boot1 is on pair with u-boot in size and runs from
>>>> DRAM.
>>> btw, please listen to henrik: he knows what he's talking about, as
>>> you can see :) henrik, thank you for correcting my technical
>>> misunderstandings, i'll try to remember them and not propagate
>>> incorrect stuff.
>> This is not about the fex syntax or uboot. The root problem is needing
>> two sets of binding for every device driver in the kernel. Pick a
>> random driver like gpio-pca953x.c and look at the source. In that file
>> there are #ifdef CONFIG_OF_ sections. Those sections are directly
>> reading the FDT binary via calls like of_get_property(node,
>> "linux,gpio-base", &size);. If fex is added to the kernel every driver
>> driver will now need both a #ifdef CONFIG_OF_ section and also a
>> #ifdef CONFIG_FEX_ section. Doing that is just crazy.
> yes. which is why they haven't done it.
>> Is Allwinner
>> going to add fex support to every single device driver in the kernel?
> no john - they've only added it to the multiplexed sections of the
> drivers which they themselves have written. such as
> drivers/usb/sun{N}i_usb/*.[ch], drivers/block/nand/sun{N}_i,
> arch/arm/mach-sun{N}i and so on.
> even the touchscreen driver that they wrote, that's got nothing to do
> with any other code in the touchscreen linux kernel source tree: it's
> more of a "meta-"driver which even has the name of the linux kernel
> module that needs to be loaded and what I2C address, GPIO options etc.
> to pass in [normally done as modprobe options in userspace].
> to be honest, there are better people to fully answer this question
> (alejandro and henrik are two that spring to mind) but you're
> definitely off-base, jon. the script.fex system deals with the pinmux
> issue in a very neat way that:
> a) has very little impact on the rest of the kernel tree [citation
> needed! i'm saying that: could someone please confirm if it's true]
> b) the linux kernel developers could, instead of criticising it,
> actually learn a great deal from.
> l.

Jon Smirl
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2013-06-06 02:01    [W:0.402 / U:1.804 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site