From 3f50425c0c9815411b760e36b48e18958819a304 Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Tue, 26 May 2009 16:30:10 +0200 Subject: microblaze_mmu_v2: TLB low level code Signed-off-by: Michal Simek --- arch/microblaze/kernel/misc.S | 120 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) create mode 100644 arch/microblaze/kernel/misc.S (limited to 'arch/microblaze') diff --git a/arch/microblaze/kernel/misc.S b/arch/microblaze/kernel/misc.S new file mode 100644 index 000000000000..d623efc9083c --- /dev/null +++ b/arch/microblaze/kernel/misc.S @@ -0,0 +1,120 @@ +/* + * Miscellaneous low-level MMU functions. + * + * Copyright (C) 2008-2009 Michal Simek + * 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 +#include +#include +#include +#include +#include + + .text +/* + * Flush MMU TLB + * + * We avoid flushing the pinned 0, 1 and possibly 2 entries. + */ +.globl _tlbia; +.align 4; +_tlbia: + addik r12, r0, 63 /* 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 + +/* + * Flush MMU TLB for a particular address (in r5) + */ +.globl _tlbie; +.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 + +/* + * Allocate TLB entry for early console + */ +.globl early_console_reg_tlb_alloc; +.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, 2 + mts rtlbx, r4 /* TLB slot 2 */ + + 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 + +/* + * Copy a whole page (4096 bytes). + */ +#define COPY_16_BYTES \ + lwi r7, r6, 0; \ + lwi r8, r6, 4; \ + lwi r9, r6, 8; \ + lwi r10, r6, 12; \ + swi r7, r5, 0; \ + swi r8, r5, 4; \ + swi r9, r5, 8; \ + swi r10, r5, 12 + + +/* FIXME DCACHE_LINE_BYTES (CONFIG_XILINX_MICROBLAZE0_DCACHE_LINE_LEN * 4)*/ +#define DCACHE_LINE_BYTES (4 * 4) + +.globl copy_page; +.align 4; +copy_page: + ori r11, r0, (PAGE_SIZE/DCACHE_LINE_BYTES) - 1 +_copy_page_loop: + COPY_16_BYTES +#if DCACHE_LINE_BYTES >= 32 + COPY_16_BYTES +#endif + addik r6, r6, DCACHE_LINE_BYTES + addik r5, r5, DCACHE_LINE_BYTES + bneid r11, _copy_page_loop + addik r11, r11, -1 + rtsd r15, 8 + nop -- cgit v1.2.3