sh: Fixup various PAGE_SIZE == 4096 assumptions.

There were a number of places that made evil PAGE_SIZE == 4k
assumptions that ended up breaking when trying to play with
8k and 64k page sizes, this fixes those up.

The most significant change is the way we load THREAD_SIZE,
previously this was done via:

	mov	#(THREAD_SIZE >> 8), reg
	shll8	reg

to avoid a memory access and allow the immediate load. With
a 64k PAGE_SIZE, we're out of range for the immediate load
size without resorting to special instructions available in
later ISAs (movi20s and so on). The "workaround" for this is
to bump up the shift to 10 and insert a shll2, which gives a
bit more flexibility while still being much cheaper than a
memory access.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/arch/sh/kernel/head.S b/arch/sh/kernel/head.S
index b5ff23264617..6aca4bc6ec5d 100644
--- a/arch/sh/kernel/head.S
+++ b/arch/sh/kernel/head.S
@@ -33,7 +33,7 @@ ENTRY(empty_zero_page)
         .long   0x00360000      /* INITRD_START */
         .long   0x000a0000      /* INITRD_SIZE */
         .long   0
-        .balign 4096,0,4096
+        .balign PAGE_SIZE,0,PAGE_SIZE
 
         .text   
 /*
@@ -70,8 +70,9 @@ ENTRY(_stext)
         !
         mov.l   2f, r0
         mov     r0, r15         ! Set initial r15 (stack pointer)
-        mov     #(THREAD_SIZE >> 8), r1
+        mov     #(THREAD_SIZE >> 10), r1
         shll8   r1              ! r1 = THREAD_SIZE
+        shll2   r1
         sub     r1, r0          !
 #ifdef CONFIG_CPU_HAS_SR_RB
         ldc     r0, r7_bank     ! ... and initial thread_info