linux/arch/microblaze/kernel/misc.S
Michal Simek af58ed854b microblaze: Fix comment for TLB
There is wrong comment for TLB. Early printk uartlite
console uses TLB 63.

Signed-off-by: Michal Simek <monstr@monstr.eu>
2010-08-02 10:44:03 +02:00

96 lines
2.1 KiB
ArmAsm

/*
* Miscellaneous low-level MMU functions.
*
* Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2008-2009 PetaLogix
* Copyright (C) 2007 Xilinx, Inc. All rights reserved.
*
* Derived from arch/ppc/kernel/misc.S
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file COPYING in the main directory of this
* archive for more details.
*/
#include <linux/linkage.h>
#include <linux/sys.h>
#include <asm/unistd.h>
#include <linux/errno.h>
#include <asm/mmu.h>
#include <asm/page.h>
.text
/*
* Flush MMU TLB
*
* We avoid flushing the pinned 0, 1 and possibly 2 entries.
*/
.globl _tlbia;
.type _tlbia, @function
.align 4;
_tlbia:
addik r12, r0, MICROBLAZE_TLB_SIZE - 1 /* flush all entries (63 - 3) */
/* isync */
_tlbia_1:
mts rtlbx, r12
nop
mts rtlbhi, r0 /* flush: ensure V is clear */
nop
addik r11, r12, -2
bneid r11, _tlbia_1 /* loop for all entries */
addik r12, r12, -1
/* sync */
rtsd r15, 8
nop
.size _tlbia, . - _tlbia
/*
* Flush MMU TLB for a particular address (in r5)
*/
.globl _tlbie;
.type _tlbie, @function
.align 4;
_tlbie:
mts rtlbsx, r5 /* look up the address in TLB */
nop
mfs r12, rtlbx /* Retrieve index */
nop
blti r12, _tlbie_1 /* Check if found */
mts rtlbhi, r0 /* flush: ensure V is clear */
nop
_tlbie_1:
rtsd r15, 8
nop
.size _tlbie, . - _tlbie
/*
* Allocate TLB entry for early console
*/
.globl early_console_reg_tlb_alloc;
.type early_console_reg_tlb_alloc, @function
.align 4;
early_console_reg_tlb_alloc:
/*
* Load a TLB entry for the UART, so that microblaze_progress() can use
* the UARTs nice and early. We use a 4k real==virtual mapping.
*/
ori r4, r0, MICROBLAZE_TLB_SIZE - 1
mts rtlbx, r4 /* TLB slot 63 */
or r4,r5,r0
andi r4,r4,0xfffff000
ori r4,r4,(TLB_WR|TLB_I|TLB_M|TLB_G)
andi r5,r5,0xfffff000
ori r5,r5,(TLB_VALID | TLB_PAGESZ(PAGESZ_4K))
mts rtlblo,r4 /* Load the data portion of the entry */
nop
mts rtlbhi,r5 /* Load the tag portion of the entry */
nop
rtsd r15, 8
nop
.size early_console_reg_tlb_alloc, . - early_console_reg_tlb_alloc