Module Name: src
Committed By: tsutsui
Date: Sun Dec 13 12:32:46 UTC 2009
Modified Files:
src/sys/arch/m68k/include: pmap_motorola.h
Log Message:
- update some comments
- use unsigned constant for shift op
To generate a diff of this commit:
cvs rdiff -u -r1.27 -r1.28 src/sys/arch/m68k/include/pmap_motorola.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/m68k/include/pmap_motorola.h
diff -u src/sys/arch/m68k/include/pmap_motorola.h:1.27 src/sys/arch/m68k/include/pmap_motorola.h:1.28
--- src/sys/arch/m68k/include/pmap_motorola.h:1.27 Fri Dec 11 18:57:44 2009
+++ src/sys/arch/m68k/include/pmap_motorola.h Sun Dec 13 12:32:46 2009
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap_motorola.h,v 1.27 2009/12/11 18:57:44 tsutsui Exp $ */
+/* $NetBSD: pmap_motorola.h,v 1.28 2009/12/13 12:32:46 tsutsui Exp $ */
/*
* Copyright (c) 1991, 1993
@@ -101,8 +101,8 @@
* We are using following segment layout in m68k pmap_motorola.c:
* 68020/030 4KB/page: l1,l2,page == 10,10,12 (%tc = 0x82c0aa00)
* 68020/030 8KB/page: l1,l2,page == 8,11,13 (%tc = 0x82d08b00)
- * 68040/060 4KB/page: l1,l2,l3,page == 7,7,6,12
- * 68040/060 8KB/page: l1,l2,l3,page == 7,7,5,13
+ * 68040/060 4KB/page: l1,l2,l3,page == 7,7,6,12 (%tc = 0x8000)
+ * 68040/060 8KB/page: l1,l2,l3,page == 7,7,5,13 (%tc = 0xc000)
*
* 68020/030 l2 size is chosen per NPTEPG, a number of page table entries
* per page, to use one whole page for PTEs per one segment table entry,
@@ -152,18 +152,20 @@
* (block 31). For convenience, the level 1 table is considered to be
* block 0.
*
- * MAX[KU]L2SIZE control how many pages of level 2 descriptors are allowed.
- * for the kernel and users. 8 implies only the initial "segment table"
- * page is used. WARNING: don't change MAXUL2SIZE unless you can allocate
- * physically contiguous pages for the ST in pmap.c!
+ * MAX[KU]L2SIZE control how many pages of level 2 descriptors are allowed
+ * for the kernel and users.
+ * 16 or 8 implies only the initial "segment table" page is used,
+ * i.e. it means PAGE_SIZE / (SG4_LEV1SIZE * sizeof(st_entry_t)).
+ * WARNING: don't change MAXUL2SIZE unless you can allocate
+ * physically contiguous pages for the ST in pmap_motorola.c!
*/
#define MAXKL2SIZE 32
-#if PAGE_SIZE == 8192
+#if PAGE_SIZE == 8192 /* NBPG / (SG4_LEV1SIZE * sizeof(st_entry_t)) */
#define MAXUL2SIZE 16
#else
#define MAXUL2SIZE 8
#endif
-#define l2tobm(n) (1 << (n))
+#define l2tobm(n) (1U << (n))
#define bmtol2(n) (ffs(n) - 1)
/*
