[PATCH v11 1/3] ARM: Add base support for ARMv7-M

[sboyd@codeaurora.org (Stephen Boyd)]

On 04/17/13 13:28, Uwe Kleine-K?nig wrote:
> Hello Stephen,
>
> On Wed, Apr 17, 2013 at 01:09:15PM -0700, Stephen Boyd wrote:
>> On 04/17/13 09:14, Uwe Kleine-K?nig wrote:
>>> +__v7m_proc_info:
>>> +	.long	0x000f0000		@ Required ID value
>>> +	.long	0x000f0000		@ Mask for ID
>>> +	.long   0			@ proc_info_list.__cpu_mm_mmu_flags
>>> +	.long   0			@ proc_info_list.__cpu_io_mmu_flags
>>> +	b	__v7m_setup		@ proc_info_list.__cpu_flush
>>> +	.long	cpu_arch_name
>>> +	.long	cpu_elf_name
>>> +	.long	HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_IDIVT
>> Mainline is detecting HWCAP_IDIVT for v7 processors so you should be
>> able to leave that part out.
> I cannot confirm that. If I drop HWCAP_IDIVT here, /proc/cpuinfo changes
> as follows:
>
> -Features	: half thumb fastmult idivt 
> +Features	: half thumb fastmult
>
> Maybe I missed to call the respective function to autodetect that? I
> don't consider that an issue big enough to justify another round for
> this series. For me letting v11 hit mainline and fix detection later is
> ok. I'll take a note to look into this, but if you want to come up with
> a patch, don't hesitate :-)

The patch that introduces the detection is
8164f7af88d9ad3a757bd14f634b23997ee77f6b. Sorry I should have read this
patch more closely. I seem to recall that M profile doesn't have the
CPUID registers in a coprocessor so it won't work. Probably easier to
leave it as is for now.

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