powerpc: Name xpn & x fields in HW Hash PTE format

Previously, the 36-bit code was using these bits, but they had
never been named in the pte format definition.  This patch just
gives those fields their proper names and adds a comment that
they are only present on some processors.

There is no functional code change.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Becky Bruce 2009-08-24 06:15:36 +00:00 committed by Benjamin Herrenschmidt
parent 948c28fe30
commit e3e1d15855

View file

@ -55,21 +55,25 @@ struct ppc_bat {
#ifndef __ASSEMBLY__
/* Hardware Page Table Entry */
/*
* Hardware Page Table Entry
* Note that the xpn and x bitfields are used only by processors that
* support extended addressing; otherwise, those bits are reserved.
*/
struct hash_pte {
unsigned long v:1; /* Entry is valid */
unsigned long vsid:24; /* Virtual segment identifier */
unsigned long h:1; /* Hash algorithm indicator */
unsigned long api:6; /* Abbreviated page index */
unsigned long rpn:20; /* Real (physical) page number */
unsigned long :3; /* Unused */
unsigned long xpn:3; /* Real page number bits 0-2, optional */
unsigned long r:1; /* Referenced */
unsigned long c:1; /* Changed */
unsigned long w:1; /* Write-thru cache mode */
unsigned long i:1; /* Cache inhibited */
unsigned long m:1; /* Memory coherence */
unsigned long g:1; /* Guarded */
unsigned long :1; /* Unused */
unsigned long x:1; /* Real page number bit 3, optional */
unsigned long pp:2; /* Page protection */
};