powerpc/mm/book3s-64: Clean up some obsolete or misleading comments

No code changes.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
index edb0991..ef6fac6 100644
--- a/arch/powerpc/mm/hash64_64k.c
+++ b/arch/powerpc/mm/hash64_64k.c
@@ -249,8 +249,7 @@
 			return 0;
 		/*
 		 * Try to lock the PTE, add ACCESSED and DIRTY if it was
-		 * a write access. Since this is 4K insert of 64K page size
-		 * also add _PAGE_COMBO
+		 * a write access.
 		 */
 		new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED;
 		if (access & _PAGE_RW)
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index ba59d59..47a0bc1 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -168,11 +168,11 @@
 		rflags |= HPTE_R_N;
 	/*
 	 * PP bits:
-	 * Linux use slb key 0 for kernel and 1 for user.
-	 * kernel areas are mapped by PP bits 00
-	 * and and there is no kernel RO (_PAGE_KERNEL_RO).
-	 * User area mapped by 0x2 and read only use by
-	 * 0x3.
+	 * Linux uses slb key 0 for kernel and 1 for user.
+	 * kernel areas are mapped with PP=00
+	 * and there is no kernel RO (_PAGE_KERNEL_RO).
+	 * User area is mapped with PP=0x2 for read/write
+	 * or PP=0x3 for read-only (including writeable but clean pages).
 	 */
 	if (pteflags & _PAGE_USER) {
 		rflags |= 0x2;