160 lines
3.9 KiB
ArmAsm
160 lines
3.9 KiB
ArmAsm
/*
|
|
* 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.
|
|
*
|
|
* arch/shmedia/boot/compressed/head.S
|
|
*
|
|
* Copied from
|
|
* arch/shmedia/kernel/head.S
|
|
* which carried the copyright:
|
|
* Copyright (C) 2000, 2001 Paolo Alberelli
|
|
*
|
|
* Modification for compressed loader:
|
|
* Copyright (C) 2002 Stuart Menefy (stuart.menefy@st.com)
|
|
*/
|
|
#include <asm/cache.h>
|
|
#include <asm/tlb.h>
|
|
#include <cpu/mmu_context.h>
|
|
#include <cpu/registers.h>
|
|
|
|
/*
|
|
* Fixed TLB entries to identity map the beginning of RAM
|
|
*/
|
|
#define MMUIR_TEXT_H 0x0000000000000003 | CONFIG_MEMORY_START
|
|
/* Enabled, Shared, ASID 0, Eff. Add. 0xA0000000 */
|
|
#define MMUIR_TEXT_L 0x000000000000009a | CONFIG_MEMORY_START
|
|
/* 512 Mb, Cacheable (Write-back), execute, Not User, Ph. Add. */
|
|
|
|
#define MMUDR_CACHED_H 0x0000000000000003 | CONFIG_MEMORY_START
|
|
/* Enabled, Shared, ASID 0, Eff. Add. 0xA0000000 */
|
|
#define MMUDR_CACHED_L 0x000000000000015a | CONFIG_MEMORY_START
|
|
/* 512 Mb, Cacheable (Write-back), read/write, Not User, Ph. Add. */
|
|
|
|
#define ICCR0_INIT_VAL ICCR0_ON | ICCR0_ICI /* ICE + ICI */
|
|
#define ICCR1_INIT_VAL ICCR1_NOLOCK /* No locking */
|
|
|
|
#define OCCR0_INIT_VAL OCCR0_ON | OCCR0_OCI | OCCR0_WB /* OCE + OCI + WB */
|
|
#define OCCR1_INIT_VAL OCCR1_NOLOCK /* No locking */
|
|
|
|
.text
|
|
|
|
.global startup
|
|
startup:
|
|
/*
|
|
* Prevent speculative fetch on device memory due to
|
|
* uninitialized target registers.
|
|
* This must be executed before the first branch.
|
|
*/
|
|
ptabs/u r63, tr0
|
|
ptabs/u r63, tr1
|
|
ptabs/u r63, tr2
|
|
ptabs/u r63, tr3
|
|
ptabs/u r63, tr4
|
|
ptabs/u r63, tr5
|
|
ptabs/u r63, tr6
|
|
ptabs/u r63, tr7
|
|
synci
|
|
|
|
/*
|
|
* Set initial TLB entries for cached and uncached regions.
|
|
* Note: PTA/BLINK is PIC code, PTABS/BLINK isn't !
|
|
*/
|
|
/* Clear ITLBs */
|
|
pta 1f, tr1
|
|
movi ITLB_FIXED, r21
|
|
movi ITLB_LAST_VAR_UNRESTRICTED+TLB_STEP, r22
|
|
1: putcfg r21, 0, r63 /* Clear MMUIR[n].PTEH.V */
|
|
addi r21, TLB_STEP, r21
|
|
bne r21, r22, tr1
|
|
|
|
/* Clear DTLBs */
|
|
pta 1f, tr1
|
|
movi DTLB_FIXED, r21
|
|
movi DTLB_LAST_VAR_UNRESTRICTED+TLB_STEP, r22
|
|
1: putcfg r21, 0, r63 /* Clear MMUDR[n].PTEH.V */
|
|
addi r21, TLB_STEP, r21
|
|
bne r21, r22, tr1
|
|
|
|
/* Map one big (512Mb) page for ITLB */
|
|
movi ITLB_FIXED, r21
|
|
movi MMUIR_TEXT_L, r22 /* PTEL first */
|
|
putcfg r21, 1, r22 /* Set MMUIR[0].PTEL */
|
|
movi MMUIR_TEXT_H, r22 /* PTEH last */
|
|
putcfg r21, 0, r22 /* Set MMUIR[0].PTEH */
|
|
|
|
/* Map one big CACHED (512Mb) page for DTLB */
|
|
movi DTLB_FIXED, r21
|
|
movi MMUDR_CACHED_L, r22 /* PTEL first */
|
|
putcfg r21, 1, r22 /* Set MMUDR[0].PTEL */
|
|
movi MMUDR_CACHED_H, r22 /* PTEH last */
|
|
putcfg r21, 0, r22 /* Set MMUDR[0].PTEH */
|
|
|
|
/* ICache */
|
|
movi ICCR_BASE, r21
|
|
movi ICCR0_INIT_VAL, r22
|
|
movi ICCR1_INIT_VAL, r23
|
|
putcfg r21, ICCR_REG0, r22
|
|
putcfg r21, ICCR_REG1, r23
|
|
synci
|
|
|
|
/* OCache */
|
|
movi OCCR_BASE, r21
|
|
movi OCCR0_INIT_VAL, r22
|
|
movi OCCR1_INIT_VAL, r23
|
|
putcfg r21, OCCR_REG0, r22
|
|
putcfg r21, OCCR_REG1, r23
|
|
synco
|
|
|
|
/*
|
|
* Enable the MMU.
|
|
* From here-on code can be non-PIC.
|
|
*/
|
|
movi SR_HARMLESS | SR_ENABLE_MMU, r22
|
|
putcon r22, SSR
|
|
movi 1f, r22
|
|
putcon r22, SPC
|
|
synco
|
|
rte /* And now go into the hyperspace ... */
|
|
1: /* ... that's the next instruction ! */
|
|
|
|
/* Set initial stack pointer */
|
|
movi datalabel stack_start, r0
|
|
ld.l r0, 0, r15
|
|
|
|
/*
|
|
* Clear bss
|
|
*/
|
|
pt 1f, tr1
|
|
movi datalabel __bss_start, r22
|
|
movi datalabel _end, r23
|
|
1: st.l r22, 0, r63
|
|
addi r22, 4, r22
|
|
bne r22, r23, tr1
|
|
|
|
/*
|
|
* Decompress the kernel.
|
|
*/
|
|
pt decompress_kernel, tr0
|
|
blink tr0, r18
|
|
|
|
/*
|
|
* Disable the MMU.
|
|
*/
|
|
movi SR_HARMLESS, r22
|
|
putcon r22, SSR
|
|
movi 1f, r22
|
|
putcon r22, SPC
|
|
synco
|
|
rte /* And now go into the hyperspace ... */
|
|
1: /* ... that's the next instruction ! */
|
|
|
|
/* Jump into the decompressed kernel */
|
|
movi datalabel (CONFIG_MEMORY_START + 0x2000)+1, r19
|
|
ptabs r19, tr0
|
|
blink tr0, r18
|
|
|
|
/* Shouldn't return here, but just in case, loop forever */
|
|
pt 1f, tr0
|
|
1: blink tr0, r63
|