From 1189be6508d45183013ddb82b18f4934193de274 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Thu, 11 Oct 2007 20:37:10 +1000 Subject: [POWERPC] Use 1TB segments This makes the kernel use 1TB segments for all kernel mappings and for user addresses of 1TB and above, on machines which support them (currently POWER5+, POWER6 and PA6T). We detect that the machine supports 1TB segments by looking at the ibm,processor-segment-sizes property in the device tree. We don't currently use 1TB segments for user addresses < 1T, since that would effectively prevent 32-bit processes from using huge pages unless we also had a way to revert to using 256MB segments. That would be possible but would involve extra complications (such as keeping track of which segment size was used when HPTEs were inserted) and is not addressed here. Parts of this patch were originally written by Ben Herrenschmidt. Signed-off-by: Paul Mackerras --- include/asm-powerpc/page_64.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'include/asm-powerpc/page_64.h') diff --git a/include/asm-powerpc/page_64.h b/include/asm-powerpc/page_64.h index 56a2df0f6836..4ee82c61e4d7 100644 --- a/include/asm-powerpc/page_64.h +++ b/include/asm-powerpc/page_64.h @@ -26,12 +26,18 @@ */ #define PAGE_FACTOR (PAGE_SHIFT - HW_PAGE_SHIFT) -/* Segment size */ +/* Segment size; normal 256M segments */ #define SID_SHIFT 28 #define SID_MASK ASM_CONST(0xfffffffff) #define ESID_MASK 0xfffffffff0000000UL #define GET_ESID(x) (((x) >> SID_SHIFT) & SID_MASK) +/* 1T segments */ +#define SID_SHIFT_1T 40 +#define SID_MASK_1T 0xffffffUL +#define ESID_MASK_1T 0xffffff0000000000UL +#define GET_ESID_1T(x) (((x) >> SID_SHIFT_1T) & SID_MASK_1T) + #ifndef __ASSEMBLY__ #include -- cgit v1.2.3