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powerpc/e6500: kexec: Handle hardware threads

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The new kernel will be expecting secondary threads to be disabled,
not spinning.

Signed-off-by: Scott Wood <scottwood@freescale.com>
This commit is contained in:
Scott Wood
2015-10-06 22:48:12 -05:00
parent 939fbf0080
commit f34b3e19fd
2 changed files with 62 additions and 0 deletions
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16
arch/powerpc/kernel/head_64.S
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@@ -182,6 +182,8 @@ exception_marker:
#ifdef CONFIG_PPC_BOOK3E
_GLOBAL(fsl_secondary_thread_init)
mfspr r4,SPRN_BUCSR
/* Enable branch prediction */
lis r3,BUCSR_INIT@h
ori r3,r3,BUCSR_INIT@l
@@ -196,10 +198,24 @@ _GLOBAL(fsl_secondary_thread_init)
* number. There are two threads per core, so shift everything
* but the low bit right by two bits so that the cpu numbering is
* continuous.
*
* If the old value of BUCSR is non-zero, this thread has run
* before. Thus, we assume we are coming from kexec or a similar
* scenario, and PIR is already set to the correct value. This
* is a bit of a hack, but there are limited opportunities for
* getting information into the thread and the alternatives
* seemed like they'd be overkill. We can't tell just by looking
* at the old PIR value which state it's in, since the same value
* could be valid for one thread out of reset and for a different
* thread in Linux.
*/
mfspr r3, SPRN_PIR
cmpwi r4,0
bne 1f
rlwimi r3, r3, 30, 2, 30
mtspr SPRN_PIR, r3
1:
#endif
_GLOBAL(generic_secondary_thread_init)