1/* 2 * Miscellaneous low-level MMU functions. 3 * 4 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu> 5 * Copyright (C) 2008-2009 PetaLogix 6 * Copyright (C) 2007 Xilinx, Inc. All rights reserved. 7 * 8 * Derived from arch/ppc/kernel/misc.S 9 * 10 * This file is subject to the terms and conditions of the GNU General 11 * Public License. See the file COPYING in the main directory of this 12 * archive for more details. 13 */ 14 15#include <linux/linkage.h> 16#include <linux/sys.h> 17#include <asm/unistd.h> 18#include <linux/errno.h> 19#include <asm/mmu.h> 20#include <asm/page.h> 21 22 .text 23/* 24 * Flush MMU TLB 25 * 26 * We avoid flushing the pinned 0, 1 and possibly 2 entries. 27 */ 28.globl _tlbia; 29.type _tlbia, @function 30.align 4; 31_tlbia: 32 addik r12, r0, MICROBLAZE_TLB_SIZE - 1 /* flush all entries (63 - 3) */ 33 /* isync */ 34_tlbia_1: 35 mts rtlbx, r12 36 nop 37 mts rtlbhi, r0 /* flush: ensure V is clear */ 38 nop 39 addik r11, r12, -2 40 bneid r11, _tlbia_1 /* loop for all entries */ 41 addik r12, r12, -1 42 /* sync */ 43 rtsd r15, 8 44 nop 45 .size _tlbia, . - _tlbia 46 47/* 48 * Flush MMU TLB for a particular address (in r5) 49 */ 50.globl _tlbie; 51.type _tlbie, @function 52.align 4; 53_tlbie: 54 mts rtlbsx, r5 /* look up the address in TLB */ 55 nop 56 mfs r12, rtlbx /* Retrieve index */ 57 nop 58 blti r12, _tlbie_1 /* Check if found */ 59 mts rtlbhi, r0 /* flush: ensure V is clear */ 60 nop 61_tlbie_1: 62 rtsd r15, 8 63 nop 64 65 .size _tlbie, . - _tlbie 66 67/* 68 * Allocate TLB entry for early console 69 */ 70.globl early_console_reg_tlb_alloc; 71.type early_console_reg_tlb_alloc, @function 72.align 4; 73early_console_reg_tlb_alloc: 74 /* 75 * Load a TLB entry for the UART, so that microblaze_progress() can use 76 * the UARTs nice and early. We use a 4k real==virtual mapping. 77 */ 78 ori r4, r0, MICROBLAZE_TLB_SIZE - 1 79 mts rtlbx, r4 /* TLB slot 63 */ 80 81 or r4,r5,r0 82 andi r4,r4,0xfffff000 83 ori r4,r4,(TLB_WR|TLB_I|TLB_M|TLB_G) 84 85 andi r5,r5,0xfffff000 86 ori r5,r5,(TLB_VALID | TLB_PAGESZ(PAGESZ_4K)) 87 88 mts rtlblo,r4 /* Load the data portion of the entry */ 89 nop 90 mts rtlbhi,r5 /* Load the tag portion of the entry */ 91 nop 92 rtsd r15, 8 93 nop 94 95 .size early_console_reg_tlb_alloc, . - early_console_reg_tlb_alloc 96