microblaze_mmu_v2: MMU update for startup code
Signed-off-by: Michal Simek <monstr@monstr.eu>
This commit is contained in:
parent
2c65b4665f
commit
5846cc608f
|
@ -3,6 +3,26 @@
|
|||
* Copyright (C) 2007-2009 PetaLogix
|
||||
* Copyright (C) 2006 Atmark Techno, Inc.
|
||||
*
|
||||
* MMU code derived from arch/ppc/kernel/head_4xx.S:
|
||||
* Copyright (c) 1995-1996 Gary Thomas <gdt@linuxppc.org>
|
||||
* Initial PowerPC version.
|
||||
* Copyright (c) 1996 Cort Dougan <cort@cs.nmt.edu>
|
||||
* Rewritten for PReP
|
||||
* Copyright (c) 1996 Paul Mackerras <paulus@cs.anu.edu.au>
|
||||
* Low-level exception handers, MMU support, and rewrite.
|
||||
* Copyright (c) 1997 Dan Malek <dmalek@jlc.net>
|
||||
* PowerPC 8xx modifications.
|
||||
* Copyright (c) 1998-1999 TiVo, Inc.
|
||||
* PowerPC 403GCX modifications.
|
||||
* Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu>
|
||||
* PowerPC 403GCX/405GP modifications.
|
||||
* Copyright 2000 MontaVista Software Inc.
|
||||
* PPC405 modifications
|
||||
* PowerPC 403GCX/405GP modifications.
|
||||
* Author: MontaVista Software, Inc.
|
||||
* frank_rowand@mvista.com or source@mvista.com
|
||||
* debbie_chu@mvista.com
|
||||
*
|
||||
* 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.
|
||||
|
@ -12,6 +32,22 @@
|
|||
#include <asm/thread_info.h>
|
||||
#include <asm/page.h>
|
||||
|
||||
#ifdef CONFIG_MMU
|
||||
#include <asm/setup.h> /* COMMAND_LINE_SIZE */
|
||||
#include <asm/mmu.h>
|
||||
#include <asm/processor.h>
|
||||
|
||||
.data
|
||||
.global empty_zero_page
|
||||
.align 12
|
||||
empty_zero_page:
|
||||
.space 4096
|
||||
.global swapper_pg_dir
|
||||
swapper_pg_dir:
|
||||
.space 4096
|
||||
|
||||
#endif /* CONFIG_MMU */
|
||||
|
||||
.text
|
||||
ENTRY(_start)
|
||||
mfs r1, rmsr
|
||||
|
@ -32,6 +68,123 @@ _copy_fdt:
|
|||
addik r3, r3, -4 /* descrement loop */
|
||||
no_fdt_arg:
|
||||
|
||||
#ifdef CONFIG_MMU
|
||||
|
||||
#ifndef CONFIG_CMDLINE_BOOL
|
||||
/*
|
||||
* handling command line
|
||||
* copy command line to __init_end. There is space for storing command line.
|
||||
*/
|
||||
or r6, r0, r0 /* incremment */
|
||||
ori r4, r0, __init_end /* load address of command line */
|
||||
tophys(r4,r4) /* convert to phys address */
|
||||
ori r3, r0, COMMAND_LINE_SIZE - 1 /* number of loops */
|
||||
_copy_command_line:
|
||||
lbu r7, r5, r6 /* r7=r5+r6 - r5 contain pointer to command line */
|
||||
sb r7, r4, r6 /* addr[r4+r6]= r7*/
|
||||
addik r6, r6, 1 /* increment counting */
|
||||
bgtid r3, _copy_command_line /* loop for all entries */
|
||||
addik r3, r3, -1 /* descrement loop */
|
||||
addik r5, r4, 0 /* add new space for command line */
|
||||
tovirt(r5,r5)
|
||||
#endif /* CONFIG_CMDLINE_BOOL */
|
||||
|
||||
#ifdef NOT_COMPILE
|
||||
/* save bram context */
|
||||
or r6, r0, r0 /* incremment */
|
||||
ori r4, r0, TOPHYS(_bram_load_start) /* save bram context */
|
||||
ori r3, r0, (LMB_SIZE - 4)
|
||||
_copy_bram:
|
||||
lw r7, r0, r6 /* r7 = r0 + r6 */
|
||||
sw r7, r4, r6 /* addr[r4 + r6] = r7*/
|
||||
addik r6, r6, 4 /* increment counting */
|
||||
bgtid r3, _copy_bram /* loop for all entries */
|
||||
addik r3, r3, -4 /* descrement loop */
|
||||
#endif
|
||||
/* We have to turn on the MMU right away. */
|
||||
|
||||
/*
|
||||
* Set up the initial MMU state so we can do the first level of
|
||||
* kernel initialization. This maps the first 16 MBytes of memory 1:1
|
||||
* virtual to physical.
|
||||
*/
|
||||
nop
|
||||
addik r3, r0, 63 /* Invalidate all TLB entries */
|
||||
_invalidate:
|
||||
mts rtlbx, r3
|
||||
mts rtlbhi, r0 /* flush: ensure V is clear */
|
||||
bgtid r3, _invalidate /* loop for all entries */
|
||||
addik r3, r3, -1
|
||||
/* sync */
|
||||
|
||||
/*
|
||||
* We should still be executing code at physical address area
|
||||
* RAM_BASEADDR at this point. However, kernel code is at
|
||||
* a virtual address. So, set up a TLB mapping to cover this once
|
||||
* translation is enabled.
|
||||
*/
|
||||
|
||||
addik r3,r0, CONFIG_KERNEL_START /* Load the kernel virtual address */
|
||||
tophys(r4,r3) /* Load the kernel physical address */
|
||||
|
||||
mts rpid,r0 /* Load the kernel PID */
|
||||
nop
|
||||
bri 4
|
||||
|
||||
/*
|
||||
* Configure and load two entries into TLB slots 0 and 1.
|
||||
* In case we are pinning TLBs, these are reserved in by the
|
||||
* other TLB functions. If not reserving, then it doesn't
|
||||
* matter where they are loaded.
|
||||
*/
|
||||
andi r4,r4,0xfffffc00 /* Mask off the real page number */
|
||||
ori r4,r4,(TLB_WR | TLB_EX) /* Set the write and execute bits */
|
||||
|
||||
andi r3,r3,0xfffffc00 /* Mask off the effective page number */
|
||||
ori r3,r3,(TLB_VALID | TLB_PAGESZ(PAGESZ_16M))
|
||||
|
||||
mts rtlbx,r0 /* TLB slow 0 */
|
||||
|
||||
mts rtlblo,r4 /* Load the data portion of the entry */
|
||||
mts rtlbhi,r3 /* Load the tag portion of the entry */
|
||||
|
||||
addik r4, r4, 0x01000000 /* Map next 16 M entries */
|
||||
addik r3, r3, 0x01000000
|
||||
|
||||
ori r6,r0,1 /* TLB slot 1 */
|
||||
mts rtlbx,r6
|
||||
|
||||
mts rtlblo,r4 /* Load the data portion of the entry */
|
||||
mts rtlbhi,r3 /* Load the tag portion of the entry */
|
||||
|
||||
/*
|
||||
* Load a TLB entry for LMB, since we need access to
|
||||
* the exception vectors, using a 4k real==virtual mapping.
|
||||
*/
|
||||
ori r6,r0,3 /* TLB slot 3 */
|
||||
mts rtlbx,r6
|
||||
|
||||
ori r4,r0,(TLB_WR | TLB_EX)
|
||||
ori r3,r0,(TLB_VALID | TLB_PAGESZ(PAGESZ_4K))
|
||||
|
||||
mts rtlblo,r4 /* Load the data portion of the entry */
|
||||
mts rtlbhi,r3 /* Load the tag portion of the entry */
|
||||
|
||||
/*
|
||||
* We now have the lower 16 Meg of RAM mapped into TLB entries, and the
|
||||
* caches ready to work.
|
||||
*/
|
||||
turn_on_mmu:
|
||||
ori r15,r0,start_here
|
||||
ori r4,r0,MSR_KERNEL_VMS
|
||||
mts rmsr,r4
|
||||
nop
|
||||
rted r15,0 /* enables MMU */
|
||||
nop
|
||||
|
||||
start_here:
|
||||
#endif /* CONFIG_MMU */
|
||||
|
||||
/* Initialize small data anchors */
|
||||
la r13, r0, _KERNEL_SDA_BASE_
|
||||
la r2, r0, _KERNEL_SDA2_BASE_
|
||||
|
@ -51,6 +204,43 @@ no_fdt_arg:
|
|||
brald r15, r8
|
||||
nop
|
||||
|
||||
#ifndef CONFIG_MMU
|
||||
la r15, r0, machine_halt
|
||||
braid start_kernel
|
||||
nop
|
||||
#else
|
||||
/*
|
||||
* Initialize the MMU.
|
||||
*/
|
||||
bralid r15, mmu_init
|
||||
nop
|
||||
|
||||
/* Go back to running unmapped so we can load up new values
|
||||
* and change to using our exception vectors.
|
||||
* On the MicroBlaze, all we invalidate the used TLB entries to clear
|
||||
* the old 16M byte TLB mappings.
|
||||
*/
|
||||
ori r15,r0,TOPHYS(kernel_load_context)
|
||||
ori r4,r0,MSR_KERNEL
|
||||
mts rmsr,r4
|
||||
nop
|
||||
bri 4
|
||||
rted r15,0
|
||||
nop
|
||||
|
||||
/* Load up the kernel context */
|
||||
kernel_load_context:
|
||||
# Keep entry 0 and 1 valid. Entry 3 mapped to LMB can go away.
|
||||
ori r5,r0,3
|
||||
mts rtlbx,r5
|
||||
nop
|
||||
mts rtlbhi,r0
|
||||
nop
|
||||
addi r15, r0, machine_halt
|
||||
ori r17, r0, start_kernel
|
||||
ori r4, r0, MSR_KERNEL_VMS
|
||||
mts rmsr, r4
|
||||
nop
|
||||
rted r17, 0 /* enable MMU and jump to start_kernel */
|
||||
nop
|
||||
#endif /* CONFIG_MMU */
|
||||
|
|
Loading…
Reference in a new issue