Re: [PATCH] gpu: host1x: use %pa to print dma_addr_t

From: Olof Johansson
Date: Mon Sep 16 2013 - 20:06:18 EST


On Mon, Sep 16, 2013 at 8:54 AM, Joe Perches <joe@xxxxxxxxxxx> wrote:
> On Mon, 2013-09-16 at 08:46 -0700, Olof Johansson wrote:
>> On Mon, Sep 16, 2013 at 8:17 AM, Thierry Reding
>> <thierry.reding@xxxxxxxxx> wrote:
>> > On Wed, Sep 11, 2013 at 09:41:49PM -0700, Olof Johansson wrote:
>> >> This removes two warnings where dma_addr_t variables were printed using
>> >> %x when built with CONFIG_ARM_LPAE=y, thus having 64-bit dma_addr_t:
>> >>
>> >> drivers/gpu/host1x/hw/cdma_hw.c:57:3: warning: format '%x' expects argument of type 'unsigned int', but argument 5 has type 'dma_addr_t'
>> >> drivers/gpu/host1x/hw/debug_hw.c:175:10: warning: format '%x' expects argument of type 'unsigned int', but argument 3 has type 'dma_addr_t'
>> >
>> > Hi Olof,
>> >
>> > I can't reproduce this. Does this perhaps depend on some other patch?
>> > When I enable LPAE I do see similar warnings in drivers/iommu/tegra-*.c
>> > and those can indeed be fixed using an equivalent patch.
>>
>> You need to enable LPAE on a platform that also selects
>> ARCH_DMA_ADDR_T_64BIT, I don't think tegra does. If you do it with
>> multi_v7_defconfig you'll see them.
>>
>> However, see discussion on another of the emails in the series; I'll
>> have to introduce a new format specifier instead.
>
> Or not.
>
> I don't know whether or not the dma_addr_t really needs a
> fixed 18 byte output length for 64 bit uses.
>
> I think always using a cast for dma_addr_t addresses like:
>
> printk("dma_addr_t: %#llx\n", (u64)addr);
>
> would probably work just fine.

Sigh. Any color would do. I just want to get rid of the mostly-bogus
warnings that makes it harder to spot real problems, I really don't
care how they're resolved.

None of the affected platforms today use 64-bit DMA anyway, so casting
down to u32 is equally acceptable. I'll repost with that instead.


-Olof
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