freebsd-dev/sys/powerpc/booke/locore.S
Rafal Jaworowski 959aea56c1 Improve kernel stack handling on e500.
- Allocate thread0.td_kstack in pmap_bootstrap(), provide guard page
- Switch to thread0.td_kstack as soon as possible i.e. right after return
  from e500_init() and before mi_startup() happens
- Clean up temp stack area
- Other minor cosmetics in machdep.c

Obtained from:	Semihalf
2008-08-26 17:07:37 +00:00

505 lines
11 KiB
ArmAsm

/*-
* Copyright (C) 2006 Semihalf, Marian Balakowicz <m8@semihalf.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#include "assym.s"
#include <machine/param.h>
#include <machine/asm.h>
#include <machine/spr.h>
#include <machine/psl.h>
#include <machine/pte.h>
#include <machine/trap.h>
#include <machine/vmparam.h>
#include <machine/tlb.h>
#include <machine/bootinfo.h>
#define TMPSTACKSZ 16384
/*
* This symbol is here for the benefit of kvm_mkdb, and is supposed to
* mark the start of kernel text.
*/
.text
.globl kernel_text
kernel_text:
/*
* Startup entry. Note, this must be the first thing in the text segment!
*/
.text
.globl __start
__start:
/*
* Assumption on a boot loader:
* - system memory starts from physical address 0
* - kernel is loaded at 16MB boundary
* - it's mapped by a single TBL1 entry
* - TLB1 mapping is 1:1 pa to va
* - all PID registers are set to the same value
*
* Loader register use:
* r1 : stack pointer
* r3 : metadata pointer
*
* We rearrange the TLB1 layout as follows:
* - find AS and entry kernel started in
* - make sure it's protected, ivalidate other entries
* - create temp entry in the second AS (make sure it's not TLB[15])
* - switch to temp mapping
* - map 16MB of RAM in TLB1[15]
* - use AS=1, set EPN to KERNBASE and RPN to kernel load address
* - switch to to TLB1[15] mapping
* - invalidate temp mapping
*
* locore register use:
* r1 : stack pointer
* r2 : unused
* r3 : kernel_text
* r4 : _end
* r5 : metadata pointer
* r6-r9 : unused
* r10 : entry we started in
* r11 : temp entry
* r12 : AS we started in
* r13-r31 : auxiliary registers
*/
/*
* Move metadata ptr to r5
*/
mr %r5, %r3
/*
* Initial cleanup
*/
li %r16, 0x200 /* Keep debug exceptions for CodeWarrior. */
mtmsr %r16
isync
#if 0
mtspr SPR_HID0, %r16
isync
msync
mtspr SPR_HID1, %r16
isync
#endif
/* Issue INV_ALL Invalidate on TLB0 */
li %r16, 0x04
tlbivax 0, %r16
isync
msync
/*
* Use tblsx to locate the TLB1 entry that maps kernel code
*/
bl 1f /* Current address */
1: mflr %r15
/* Find entry that maps current address */
mfspr %r17, SPR_PID0
slwi %r17, %r17, MAS6_SPID0_SHIFT
mtspr SPR_MAS6, %r17
isync
tlbsx 0, %r15
/* Copy entry number to r10 */
mfspr %r17, SPR_MAS0
rlwinm %r10, %r17, 16, 28, 31
/* Invalidate TLB1, skipping our entry. */
mfspr %r17, SPR_TLB1CFG /* Get number of entries */
andi. %r17, %r17, TLBCFG_NENTRY_MASK@l
li %r16, 0 /* Start from Entry 0 */
2: lis %r15, MAS0_TLBSEL1@h /* Select TLB1 */
rlwimi %r15, %r16, 16, 12, 15
mtspr SPR_MAS0, %r15
isync
tlbre
mfspr %r15, SPR_MAS1
cmpw %r16, %r10
beq 3f
/* Clear VALID and IPROT bits for other entries */
rlwinm %r15, %r15, 0, 2, 31
mtspr SPR_MAS1, %r15
isync
tlbwe
isync
msync
3: addi %r16, %r16, 1
cmpw %r16, %r17 /* Check if this is the last entry */
bne 2b
/*
* Create temporary mapping in the other Address Space
*/
lis %r17, MAS0_TLBSEL1@h /* Select TLB1 */
rlwimi %r17, %r10, 16, 12, 15 /* Select our entry */
mtspr SPR_MAS0, %r17
isync
tlbre /* Read it in */
/* Prepare and write temp entry */
lis %r17, MAS0_TLBSEL1@h /* Select TLB1 */
addi %r11, %r10, 0x1 /* Use next entry. */
rlwimi %r17, %r11, 16, 12, 15 /* Select temp entry */
mtspr SPR_MAS0, %r17
isync
mfspr %r16, SPR_MAS1
li %r15, 1 /* AS 1 */
rlwimi %r16, %r15, 12, 19, 19
mtspr SPR_MAS1, %r16
li %r17, 0
rlwimi %r16, %r17, 0, 8, 15 /* Global mapping, TID=0 */
isync
tlbwe
isync
msync
mfmsr %r16
ori %r16, %r16, 0x30 /* Switch to AS 1. */
bl 4f /* Find current execution address */
4: mflr %r15
addi %r15, %r15, 20 /* Increment to instruction after rfi */
mtspr SPR_SRR0, %r15
mtspr SPR_SRR1, %r16
rfi /* Switch context */
/*
* Invalidate initial entry
*/
mr %r22, %r10
bl tlb1_inval_entry
/*
* Setup final mapping in TLB1[1] and switch to it
*/
/* Final kernel mapping, map in 16 MB of RAM */
lis %r16, MAS0_TLBSEL1@h /* Select TLB1 */
li %r17, 1 /* Entry 1 */
rlwimi %r16, %r17, 16, 12, 15
mtspr SPR_MAS0, %r16
isync
li %r16, (TLB_SIZE_16M << MAS1_TSIZE_SHIFT)@l
oris %r16, %r16, (MAS1_VALID | MAS1_IPROT)@h
mtspr SPR_MAS1, %r16
isync
lis %r19, KERNBASE@h
ori %r19, %r19, KERNBASE@l
mtspr SPR_MAS2, %r19 /* Set final EPN, clear WIMG */
isync
bl 5f
5: mflr %r16 /* Use current address */
lis %r18, 0xff00 /* 16MB alignment mask */
and %r16, %r16, %r18
mr %r25, %r16 /* Copy kernel load address */
ori %r16, %r16, (MAS3_SX | MAS3_SW | MAS3_SR)@l
mtspr SPR_MAS3, %r16 /* Set RPN and protection */
isync
tlbwe
isync
msync
/* Switch to the above TLB1[1] mapping */
lis %r18, 0x00ff /* 16MB offset mask */
ori %r18, %r18, 0xffff
bl 6f
6: mflr %r20 /* Use current address */
and %r20, %r20, %r18 /* Offset from kernel load address */
add %r20, %r20, %r19 /* Move to kernel virtual address */
addi %r20, %r20, 32 /* Increment to instr. after rfi */
li %r21, 0x200
mtspr SPR_SRR0, %r20
mtspr SPR_SRR1, %r21
rfi
/* Save kernel load address for later use */
lis %r24, kernload@ha
addi %r24, %r24, kernload@l
stw %r25, 0(%r24)
/*
* Invalidate temp mapping
*/
mr %r22, %r11
bl tlb1_inval_entry
/*
* Setup a temporary stack
*/
lis %r1, tmpstack@ha
addi %r1, %r1, tmpstack@l
addi %r1, %r1, (TMPSTACKSZ - 8)
/*
* Intialise exception vector offsets
*/
bl ivor_setup
/*
* Jump to system initialization code
*
* Setup first two arguments for e500_init, metadata (r5) is already in place.
*/
lis %r3, kernel_text@ha
addi %r3, %r3, kernel_text@l
lis %r4, _end@ha
addi %r4, %r4, _end@l
bl e500_init
/* Switch to thread0.td_kstack */
mr %r1, %r3
li %r3, 0
stw %r3, 0(%r1)
bl mi_startup /* Machine independet part, does not return */
/************************************************************************/
/* locore subroutines */
/************************************************************************/
tlb1_inval_entry:
lis %r17, MAS0_TLBSEL1@h /* Select TLB1 */
rlwimi %r17, %r22, 16, 12, 15 /* Select our entry */
mtspr SPR_MAS0, %r17
isync
tlbre /* Read it in */
li %r16, 0
mtspr SPR_MAS1, %r16
isync
tlbwe
isync
msync
blr
ivor_setup:
/* Set base address of interrupt handler routines */
lis %r21, interrupt_vector_base@h
mtspr SPR_IVPR, %r21
/* Assign interrupt handler routines offsets */
li %r21, int_critical_input@l
mtspr SPR_IVOR0, %r21
li %r21, int_machine_check@l
mtspr SPR_IVOR1, %r21
li %r21, int_data_storage@l
mtspr SPR_IVOR2, %r21
li %r21, int_instr_storage@l
mtspr SPR_IVOR3, %r21
li %r21, int_external_input@l
mtspr SPR_IVOR4, %r21
li %r21, int_alignment@l
mtspr SPR_IVOR5, %r21
li %r21, int_program@l
mtspr SPR_IVOR6, %r21
li %r21, int_syscall@l
mtspr SPR_IVOR8, %r21
li %r21, int_decrementer@l
mtspr SPR_IVOR10, %r21
li %r21, int_fixed_interval_timer@l
mtspr SPR_IVOR11, %r21
li %r21, int_watchdog@l
mtspr SPR_IVOR12, %r21
li %r21, int_data_tlb_error@l
mtspr SPR_IVOR13, %r21
li %r21, int_inst_tlb_error@l
mtspr SPR_IVOR14, %r21
li %r21, int_debug@l
mtspr SPR_IVOR15, %r21
blr
/*
* void tlb1_inval_va(vm_offset_t va)
*
* r3 - va to invalidate
*/
ENTRY(tlb1_inval_va)
/* EA mask */
lis %r6, 0xffff
ori %r6, %r6, 0xf000
and %r3, %r3, %r6
/* Select TLB1 */
ori %r3, %r3, 0x08
isync
tlbivax 0, %r3
isync
msync
blr
/*
* void tlb0_inval_va(vm_offset_t va)
*
* r3 - va to invalidate
*/
ENTRY(tlb0_inval_va)
/* EA mask, this also clears TLBSEL, selecting TLB0 */
lis %r6, 0xffff
ori %r6, %r6, 0xf000
and %r3, %r3, %r6
isync
tlbivax 0, %r3
isync
msync
blr
/*
* Cache disable/enable/inval sequences according
* to section 2.16 of E500CORE RM.
*/
ENTRY(dcache_inval)
/* Invalidate d-cache */
mfspr %r3, SPR_L1CSR0
ori %r3, %r3, (L1CSR0_DCFI | L1CSR0_DCLFR)@l
msync
isync
mtspr SPR_L1CSR0, %r3
isync
blr
ENTRY(dcache_disable)
/* Disable d-cache */
mfspr %r3, SPR_L1CSR0
li %r4, L1CSR0_DCE@l
not %r4, %r4
and %r3, %r3, %r4
msync
isync
mtspr SPR_L1CSR0, %r3
isync
blr
ENTRY(dcache_enable)
/* Enable d-cache */
mfspr %r3, SPR_L1CSR0
oris %r3, %r3, (L1CSR0_DCPE | L1CSR0_DCE)@h
ori %r3, %r3, (L1CSR0_DCPE | L1CSR0_DCE)@l
msync
isync
mtspr SPR_L1CSR0, %r3
isync
blr
ENTRY(icache_inval)
/* Invalidate i-cache */
mfspr %r3, SPR_L1CSR1
ori %r3, %r3, (L1CSR1_ICFI | L1CSR1_ICLFR)@l
isync
mtspr SPR_L1CSR1, %r3
isync
blr
ENTRY(icache_disable)
/* Disable i-cache */
mfspr %r3, SPR_L1CSR1
li %r4, L1CSR1_ICE@l
not %r4, %r4
and %r3, %r3, %r4
isync
mtspr SPR_L1CSR1, %r3
isync
blr
ENTRY(icache_enable)
/* Enable i-cache */
mfspr %r3, SPR_L1CSR1
oris %r3, %r3, (L1CSR1_ICPE | L1CSR1_ICE)@h
ori %r3, %r3, (L1CSR1_ICPE | L1CSR1_ICE)@l
isync
mtspr SPR_L1CSR1, %r3
isync
blr
/*
* int setfault()
*
* Similar to setjmp to setup for handling faults on accesses to user memory.
* Any routine using this may only call bcopy, either the form below,
* or the (currently used) C code optimized, so it doesn't use any non-volatile
* registers.
*/
.globl setfault
setfault:
mflr %r0
mfsprg0 %r4
lwz %r4, PC_CURTHREAD(%r4)
lwz %r4, TD_PCB(%r4)
stw %r3, PCB_ONFAULT(%r4)
mfcr %r10
mfctr %r11
mfxer %r12
stw %r0, 0(%r3)
stw %r1, 4(%r3)
stw %r2, 8(%r3)
stmw %r10, 12(%r3) /* store CR, CTR, XER, [r13 .. r31] */
li %r3, 0 /* return FALSE */
blr
/************************************************************************/
/* Data section */
/************************************************************************/
.data
.align 4
tmpstack:
.space TMPSTACKSZ
/*
* Compiled KERNBASE locations
*/
.globl kernbase
.set kernbase, KERNBASE
/*
* Globals
*/
#define INTRCNT_COUNT 256 /* max(HROWPIC_IRQMAX,OPENPIC_IRQMAX) */
GLOBAL(kernload)
.long
GLOBAL(intrnames)
.space INTRCNT_COUNT * (MAXCOMLEN + 1) * 2
GLOBAL(eintrnames)
.align 4
GLOBAL(intrcnt)
.space INTRCNT_COUNT * 4 * 2
GLOBAL(eintrcnt)
#include <powerpc/booke/trap_subr.S>