From: tushar.jagad@linaro.org (Tushar Jagad)
To: linux-arm-kernel@lists.infradead.org
Subject: [RFC PATCH 3/4] ARM64: Big Endian fixes for kernel booting
Date: Wed, 16 Oct 2013 12:34:48 +0530 [thread overview]
Message-ID: <525E3A90.4070809@linaro.org> (raw)
In-Reply-To: <525D8860.7080204@codeaurora.org>
Hi Christopher,
On 10/15/2013 11:54 PM, Christopher Covington wrote:
>> /*
>> + * Set el0-el1-el2 to Big endian
>> + */
>
> It might be helpful to say why this has to be done (each level needs to be set
> up before it's used?) and maybe list them in the order they're set up in.
Sure will cover more details in the comment.
>> +#if defined(CONFIG_CPU_BIG_ENDIAN)
>> +ENTRY(setend_be)
>> + mrs x21, CurrentEL
>> + cmp x21, #PSR_MODE_EL2t
>> + b.ne setend_be_el1_el0
>
> Make sure to use tabs rather than spaces and run checkpatch.pl.
Somehow this got skipped. Thanks for pointing it out.
>
>> +
>> +setend_be_el2:
>> + mrs x21, sctlr_el2
>> + mov x22, #(1<<25)
>> + orr x21, x21, x22
>> + msr sctlr_el2, x21
>> + isb
>> +
>> +setend_be_el1_el0:
>> + mrs x21, sctlr_el1
>> + mov x22, #(3<<24)
>> + orr x21, x21, x22
>> + msr sctlr_el1, x21
>> + isb
>> +
>> + ret
>> +ENDPROC(setend_be)
>> +#endif /* defined(CONFIG_CPU_BIG_ENDIAN) */
>> +
>> +/*
>> * If we're fortunate enough to boot at EL2, ensure that the world is
>> * sane before dropping to EL1.
>> */
>> @@ -181,7 +210,11 @@ ENTRY(el2_setup)
>>
>> /* sctlr_el1 */
>> mov x0, #0x0800 // Set/clear RES{1,0} bits
>> +#if defined(CONFIG_CPU_BIG_ENDIAN)
>> + movk x0, #0x33d0, lsl #16
>> +#else
>> movk x0, #0x30d0, lsl #16
>> +#endif
>> msr sctlr_el1, x0
>
> This may be easier to read if the magic number were ifdef'ed instead of the code.
Will change this as well.
--
Regards,
Tushar
next prev parent reply other threads:[~2013-10-16 7:04 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-11 12:22 [RFC PATCH 0/4] Big Endian support for ARM64 kernel Ankit Jindal
2013-10-11 12:22 ` [RFC PATCH 1/4] ARM64: Add Kconfig option to enable Big Endian kernel Ankit Jindal
2013-10-15 18:09 ` Christopher Covington
2013-10-16 6:49 ` Tushar Jagad
2013-10-16 14:30 ` Christopher Covington
2013-10-11 12:22 ` [RFC PATCH 2/4] ARM64: Include appropriate byteorder for Big Endian Ankit Jindal
2013-10-11 12:22 ` [RFC PATCH 3/4] ARM64: Big Endian fixes for kernel booting Ankit Jindal
2013-10-11 12:52 ` Ankit Jindal
2013-10-15 18:24 ` Christopher Covington
2013-10-16 7:04 ` Tushar Jagad [this message]
2013-10-11 12:22 ` [RFC PATCH 4/4] ARM64: Support for 32-bit big endian userspace Ankit Jindal
2013-10-15 18:09 ` [RFC PATCH 0/4] Big Endian support for ARM64 kernel Christopher Covington
2013-10-16 8:05 ` Tushar Jagad
2013-10-16 14:40 ` Christopher Covington
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