ARM: zImage: some comments for __armv3_mpu_cache_on

__armv3_mpu_cache_on seems broken.  As there is noone around who knows
about these machines just keep the code as is but point out the strange
things.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
This commit is contained in:
Uwe Kleine-König 2010-01-26 22:14:23 +01:00
parent 88237c25aa
commit 4a8d57a54f

View file

@ -396,12 +396,18 @@ __armv3_mpu_cache_on:
mov r0, #0
mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
/*
* ?? ARMv3 MMU does not allow reading the control register,
* does this really work on ARMv3 MPU?
*/
mrc p15, 0, r0, c1, c0, 0 @ read control reg
@ .... .... .... WC.M
orr r0, r0, #0x000d @ .... .... .... 11.1
/* ?? this overwrites the value constructed above? */
mov r0, #0
mcr p15, 0, r0, c1, c0, 0 @ write control reg
/* ?? invalidate for the second time? */
mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
mov pc, lr