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authorLeonid Yegoshin <Leonid.Yegoshin@imgtec.com>2013-11-14 16:12:31 +0000
committerRalf Baechle <ralf@linux-mips.org>2014-01-22 20:19:00 +0100
commit75b5b5e0a262790fa11043fe45700499c7e3d818 (patch)
tree3c5af9caa9c5478668159ff34db0ab34b51d7511 /arch/mips/include/asm/page.h
parent601cfa7b6fb657cff9e8f77bbcce79f75dd7ab74 (diff)
MIPS: Add support for FTLBs
The Fixed Page Size TLB (FTLB) is a set-associative dual entry TLB. Its purpose is to reduce the number of TLB misses by increasing the effective TLB size and keep the implementation complexity to minimum levels. A supported core can have both VTLB and FTLB. Reviewed-by: James Hogan <james.hogan@imgtec.com> Reviewed-by: Paul Burton <paul.burton@imgtec.com> Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Signed-off-by: John Crispin <blogic@openwrt.org> Patchwork: http://patchwork.linux-mips.org/patch/6139/
Diffstat (limited to 'arch/mips/include/asm/page.h')
-rw-r--r--arch/mips/include/asm/page.h25
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h
index f6be4741f7e..5e08bcc7489 100644
--- a/arch/mips/include/asm/page.h
+++ b/arch/mips/include/asm/page.h
@@ -11,6 +11,8 @@
#include <spaces.h>
#include <linux/const.h>
+#include <linux/kernel.h>
+#include <asm/mipsregs.h>
/*
* PAGE_SHIFT determines the page size
@@ -33,6 +35,29 @@
#define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
#define PAGE_MASK (~((1 << PAGE_SHIFT) - 1))
+/*
+ * This is used for calculating the real page sizes
+ * for FTLB or VTLB + FTLB confugrations.
+ */
+static inline unsigned int page_size_ftlb(unsigned int mmuextdef)
+{
+ switch (mmuextdef) {
+ case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
+ if (PAGE_SIZE == (1 << 30))
+ return 5;
+ if (PAGE_SIZE == (1llu << 32))
+ return 6;
+ if (PAGE_SIZE > (256 << 10))
+ return 7; /* reserved */
+ /* fall through */
+ case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
+ return (PAGE_SHIFT - 10) / 2;
+ default:
+ panic("Invalid FTLB configuration with Conf4_mmuextdef=%d value\n",
+ mmuextdef >> 14);
+ }
+}
+
#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
#define HPAGE_SHIFT (PAGE_SHIFT + PAGE_SHIFT - 3)
#define HPAGE_SIZE (_AC(1,UL) << HPAGE_SHIFT)