leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

[PATCH] powerpc: work around a cell interrupt HW bug

Browse Source 
Apparently we have found a bug in the CPU that causes
external interrupts to sometimes get disabled indefinitely.
This adds a workaround for the problem.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Arnd Bergmann 2006-03-23 00:00:07 +01:00 committed by Paul Mackerras
parent d0e57c6837
commit 5536408c21
1 changed files with 18 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
arch/powerpc/platforms/cell/interrupt.c
View File

@ -63,7 +63,24 @@ static DEFINE_PER_CPU(struct iic, iic);
void iic_local_enable(void)
{
out_be64(&__get_cpu_var(iic).regs->prio, 0xff);
struct iic *iic = &__get_cpu_var(iic);
u64 tmp;
/*
* There seems to be a bug that is present in DD2.x CPUs
* and still only partially fixed in DD3.1.
* This bug causes a value written to the priority register
* not to make it there, resulting in a system hang unless we
* write it again.
* Masking with 0xf0 is done because the Cell BE does not
* implement the lower four bits of the interrupt priority,
* they always read back as zeroes, although future CPUs
* might implement different bits.
*/
do {
out_be64(&iic->regs->prio, 0xff);
tmp = in_be64(&iic->regs->prio);
} while ((tmp & 0xf0) != 0xf0);
}
void iic_local_disable(void)