u-boot/arch/nds32/cpu/n1213/start.S

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/*
* Andesboot - Startup Code for Whitiger core
*
* Copyright (C) 2006 Andes Technology Corporation
* Copyright (C) 2006 Shawn Lin <nobuhiro@andestech.com>
* Copyright (C) 2011 Macpaul Lin <macpaul@andestech.com>
* Greentime Hu <greentime@andestech.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
.pic
#include <asm-offsets.h>
#include <config.h>
#include <common.h>
#include <asm/macro.h>
/*
* Jump vector table for EVIC mode
*/
#define ENA_DCAC 2UL
#define DIS_DCAC ~ENA_DCAC
#define ICAC_MEM_KBF_ISET (0x07) ! I Cache sets per way
#define ICAC_MEM_KBF_IWAY (0x07<<3) ! I cache ways
#define ICAC_MEM_KBF_ISZ (0x07<<6) ! I cache line size
#define DCAC_MEM_KBF_DSET (0x07) ! D Cache sets per way
#define DCAC_MEM_KBF_DWAY (0x07<<3) ! D cache ways
#define DCAC_MEM_KBF_DSZ (0x07<<6) ! D cache line size
#define PSW $ir0
#define EIT_INTR_PSW $ir1 ! interruption $PSW
#define EIT_PREV_IPSW $ir2 ! previous $IPSW
#define EIT_IVB $ir3 ! intr vector base address
#define EIT_EVA $ir4 ! MMU related Exception VA reg
#define EIT_PREV_EVA $ir5 ! previous $eva
#define EIT_ITYPE $ir6 ! interruption type
#define EIT_PREV_ITYPE $ir7 ! prev intr type
#define EIT_MACH_ERR $ir8 ! machine error log
#define EIT_INTR_PC $ir9 ! Interruption PC
#define EIT_PREV_IPC $ir10 ! previous $IPC
#define EIT_OVL_INTR_PC $ir11 ! overflow interruption PC
#define EIT_PREV_P0 $ir12 ! prev $P0
#define EIT_PREV_P1 $ir13 ! prev $p1
#define CR_ICAC_MEM $cr1 ! I-cache/memory config reg
#define CR_DCAC_MEM $cr2 ! D-cache/memory config reg
#define MR_CAC_CTL $mr8
.globl _start
_start: j reset
j tlb_fill
j tlb_not_present
j tlb_misc
j tlb_vlpt_miss
j machine_error
j debug
j general_exception
j syscall
j internal_interrupt ! H0I
j internal_interrupt ! H1I
j internal_interrupt ! H2I
j internal_interrupt ! H3I
j internal_interrupt ! H4I
j internal_interrupt ! H5I
j software_interrupt ! S0I
.balign 16
/*
* Andesboot Startup Code (reset vector)
*
* 1. bootstrap
* 1.1 reset - start of u-boot
* 1.2 to superuser mode - as is when reset
* 1.4 Do lowlevel_init
* - (this will jump out to lowlevel_init.S in SoC)
* - (lowlevel_init)
* 1.3 Turn off watchdog timer
* - (this will jump out to watchdog.S in SoC)
* - (turnoff_watchdog)
* 2. Do critical init when reboot (not from mem)
* 3. Relocate andesboot to ram
* 4. Setup stack
* 5. Jump to second stage (board_init_r)
*/
/* Note: TEXT_BASE is defined by the (board-dependent) linker script */
.globl _TEXT_BASE
_TEXT_BASE:
.word CONFIG_SYS_TEXT_BASE
/*
* These are defined in the board-specific linker script.
* Subtracting _start from them lets the linker put their
* relative position in the executable instead of leaving
* them null.
*/
#ifdef CONFIG_USE_IRQ
/* IRQ stack memory (calculated at run-time) */
.globl IRQ_STACK_START
IRQ_STACK_START:
.word 0x0badc0de
/* IRQ stack memory (calculated at run-time) */
.globl FIQ_STACK_START
FIQ_STACK_START:
.word 0x0badc0de
#endif
/* IRQ stack memory (calculated at run-time) + 8 bytes */
.globl IRQ_STACK_START_IN
IRQ_STACK_START_IN:
.word 0x0badc0de
/*
* The bootstrap code of nds32 core
*/
reset:
/*
* gp = ~0 for burn mode
* = ~load_address for load mode
*/
reset_gp:
.relax_hint 0
sethi $gp, hi20(_GLOBAL_OFFSET_TABLE_-8)
.relax_hint 0
ori $gp, $gp, lo12(_GLOBAL_OFFSET_TABLE_-4)
add5.pc $gp
set_ivb:
li $r0, 0x0
/* turn on BTB */
mtsr $r0, $misc_ctl
/* set IVIC, vector size: 4 bytes, base: 0x0 */
mtsr $r0, $ivb
#ifndef CONFIG_SKIP_LOWLEVEL_INIT
jal lowlevel_init
/*
* gp = ~VMA for burn mode
* = ~load_address for load mode
*/
update_gp:
.relax_hint 0
sethi $gp, hi20(_GLOBAL_OFFSET_TABLE_-8)
.relax_hint 0
ori $gp, $gp, lo12(_GLOBAL_OFFSET_TABLE_-4)
add5.pc $gp
#endif
/*
* do critical initializations first (shall be in short time)
* do self_relocation ASAP.
*/
/*
* Set the N1213 (Whitiger) core to superuser mode
* According to spec, it is already when reset
*/
#ifndef CONFIG_SKIP_TRUNOFF_WATCHDOG
jal turnoff_watchdog
#endif
/*
* Do CPU critical regs init only at reboot,
* not when booting from ram
*/
#ifdef CONFIG_INIT_CRITICAL
jal cpu_init_crit ! Do CPU critical regs init
#endif
/*
* Set stackpointer in internal RAM to call board_init_f
* $sp must be 8-byte alignment for ABI compliance.
*/
call_board_init_f:
li $sp, CONFIG_SYS_INIT_SP_ADDR
li $r10, GD_SIZE /* get GD size */
sub $sp, $sp, $r10 /* GD start addr */
move $r10, $sp
li $r0, 0x00000000
#ifdef __PIC__
#ifdef __NDS32_N1213_43U1H__
/* __NDS32_N1213_43U1H__ implies NDS32 V0 ISA */
la $r15, board_init_f ! store function address into $r15
#endif
#endif
j board_init_f ! jump to board_init_f() in lib/board.c
/*
* void relocate_code (addr_sp, gd, addr_moni)
*
* This "function" does not return, instead it continues in RAM
* after relocating the monitor code.
*
*/
/*
* gp = ~RAM_SIZE - TEXT_SIZE for burn/load mode
*/
.globl relocate_code
relocate_code:
move $r4, $r0 /* save addr_sp */
move $r5, $r1 /* save addr of gd */
move $r6, $r2 /* save addr of destination */
/* Set up the stack */
stack_setup:
move $sp, $r4
la $r0, _start@GOTOFF
beq $r0, $r6, clear_bss /* skip relocation */
la $r1, _end@GOTOFF
move $r2, $r6 /* r2 <- scratch for copy_loop */
copy_loop:
lwi.p $r7, [$r0], #4
swi.p $r7, [$r2], #4
blt $r0, $r1, copy_loop
/*
* fix relocations related issues
*/
fix_relocations:
l.w $r0, _TEXT_BASE@GOTOFF /* r0 <- Text base */
sub $r9, $r6, $r0 /* r9 <- relocation offset */
la $r7, __rel_dyn_start@GOTOFF
add $r7, $r7, $r9 /* r2 <- rel __got_start in RAM */
la $r8, __rel_dyn_end@GOTOFF
add $r8, $r8, $r9 /* r2 <- rel __got_start in RAM */
li $r3, #0x2a /* R_NDS32_RELATIVE */
1:
lmw.bim $r0, [$r7], $r2 /* r0,r1,r2 <- adr,type,addend */
bne $r1, $r3, 2f
add $r0, $r0, $r9
add $r2, $r2, $r9
sw $r2, [$r0]
2:
blt $r7, $r8, 1b
clear_bss:
la $r0, __bss_start@GOTOFF /* r0 <- rel __bss_start in FLASH */
add $r0, $r0, $r9 /* r0 <- rel __bss_start in FLASH */
la $r1, __bss_end@GOTOFF /* r1 <- rel __bss_end in RAM */
add $r1, $r1, $r9 /* r0 <- rel __bss_end in RAM */
li $r2, 0x00000000 /* clear */
clbss_l:
sw $r2, [$r0] /* clear loop... */
addi $r0, $r0, #4
bne $r0, $r1, clbss_l
/*
* We are done. Do not return, instead branch to second part of board
* initialization, now running from RAM.
*/
call_board_init_r:
la $r0, board_init_r@GOTOFF
move $lp, $r0 /* offset of board_init_r() */
add $lp, $lp, $r9 /* real address of board_init_r() */
/* setup parameters for board_init_r */
move $r0, $r5 /* gd_t */
move $r1, $r6 /* dest_addr */
#ifdef __PIC__
#ifdef __NDS32_N1213_43U1H__ /* NDS32 V0 ISA */
move $r15, $lp /* store function address into $r15 */
#endif
#endif
/* jump to it ... */
jr $lp /* jump to board_init_r() */
/*
* Initialize CPU critical registers
*
* 1. Setup control registers
* 1.1 Mask all IRQs
* 1.2 Flush cache and TLB
* 1.3 Disable MMU and cache
* 2. Setup memory timing
*/
cpu_init_crit:
move $r0, $lp /* push ra */
/* Disable Interrupts by clear GIE in $PSW reg */
setgie.d
/* Flush caches and TLB */
/* Invalidate caches */
jal invalidate_icac
jal invalidate_dcac
/* Flush TLB */
mfsr $p0, $MMU_CFG
andi $p0, $p0, 0x3 ! MMPS
li $p1, 0x2 ! TLB MMU
bne $p0, $p1, 1f
tlbop flushall ! Flush TLB
1:
! Disable MMU, Dcache
! Whitiger is MMU disabled when reset
! Disable the D$
mfsr $p0, MR_CAC_CTL ! Get the $CACHE_CTL reg
li $p1, DIS_DCAC
and $p0, $p0, $p1 ! Set DC_EN bit
mtsr $p0, MR_CAC_CTL ! write back the $CACHE_CTL reg
isb
move $lp, $r0
2:
ret
/*
* Invalidate I$
*/
invalidate_icac:
! read $cr1(I CAC/MEM cfg. reg.) configuration
mfsr $t0, CR_ICAC_MEM
! Get the ISZ field
andi $p0, $t0, ICAC_MEM_KBF_ISZ
! if $p0=0, then no I CAC existed
beqz $p0, end_flush_icache
! get $p0 the index of I$ block
srli $p0, $p0, 6
! $t1= bit width of I cache line size(ISZ)
addi $t1, $p0, 2
li $t4, 1
sll $t5, $t4, $t1 ! get $t5 cache line size
andi $p1, $t0, ICAC_MEM_KBF_ISET ! get the ISET field
addi $t2, $p1, 6 ! $t2= bit width of ISET
andi $p1, $t0, ICAC_MEM_KBF_IWAY ! get bitfield of Iway
srli $p1, $p1, 3
addi $p1, $p1, 1 ! then $p1 is I way number
add $t3, $t2, $t1 ! SHIFT
sll $p1, $p1, $t3 ! GET the total cache size
ICAC_LOOP:
sub $p1, $p1, $t5
cctl $p1, L1I_IX_INVAL
bnez $p1, ICAC_LOOP
end_flush_icache:
ret
/*
* Invalidate D$
*/
invalidate_dcac:
! read $cr2(D CAC/MEM cfg. reg.) configuration
mfsr $t0, CR_DCAC_MEM
! Get the DSZ field
andi $p0, $t0, DCAC_MEM_KBF_DSZ
! if $p0=0, then no D CAC existed
beqz $p0, end_flush_dcache
! get $p0 the index of D$ block
srli $p0, $p0, 6
! $t1= bit width of D cache line size(DSZ)
addi $t1, $p0, 2
li $t4, 1
sll $t5, $t4, $t1 ! get $t5 cache line size
andi $p1, $t0, DCAC_MEM_KBF_DSET ! get the DSET field
addi $t2, $p1, 6 ! $t2= bit width of DSET
andi $p1, $t0, DCAC_MEM_KBF_DWAY ! get bitfield of D way
srli $p1, $p1, 3
addi $p1, $p1, 1 ! then $p1 is D way number
add $t3, $t2, $t1 ! SHIFT
sll $p1, $p1, $t3 ! GET the total cache size
DCAC_LOOP:
sub $p1, $p1, $t5
cctl $p1, L1D_IX_INVAL
bnez $p1, DCAC_LOOP
end_flush_dcache:
ret
/*
* Interrupt handling
*/
/*
* exception handlers
*/
.align 5
.macro SAVE_ALL
! FIXME: Other way to get PC?
! FIXME: Update according to the newest spec!!
1:
li $r28, 1
push $r28
mfsr $r28, PSW ! $PSW
push $r28
mfsr $r28, EIT_EVA ! $ir1 $EVA
push $r28
mfsr $r28, EIT_ITYPE ! $ir2 $ITYPE
push $r28
mfsr $r28, EIT_MACH_ERR ! $ir3 Mach Error
push $r28
mfsr $r28, EIT_INTR_PSW ! $ir5 $IPSW
push $r28
mfsr $r28, EIT_PREV_IPSW ! $ir6 prev $IPSW
push $r28
mfsr $r28, EIT_PREV_EVA ! $ir7 prev $EVA
push $r28
mfsr $r28, EIT_PREV_ITYPE ! $ir8 prev $ITYPE
push $r28
mfsr $r28, EIT_INTR_PC ! $ir9 Interruption PC
push $r28
mfsr $r28, EIT_PREV_IPC ! $ir10 prev INTR_PC
push $r28
mfsr $r28, EIT_OVL_INTR_PC ! $ir11 Overflowed INTR_PC
push $r28
mfusr $r28, $d1.lo
push $r28
mfusr $r28, $d1.hi
push $r28
mfusr $r28, $d0.lo
push $r28
mfusr $r28, $d0.hi
push $r28
pushm $r0, $r30 ! store $sp-$r31, ra-$r30, $gp-$r29, $r28-$fp
addi $sp, $sp, -4 ! make room for implicit pt_regs parameters
.endm
.align 5
tlb_fill:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 1 ! Determine interruption type
bal do_interruption
.align 5
tlb_not_present:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 2 ! Determine interruption type
bal do_interruption
.align 5
tlb_misc:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 3 ! Determine interruption type
bal do_interruption
.align 5
tlb_vlpt_miss:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 4 ! Determine interruption type
bal do_interruption
.align 5
machine_error:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 5 ! Determine interruption type
bal do_interruption
.align 5
debug:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 6 ! Determine interruption type
bal do_interruption
.align 5
general_exception:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 7 ! Determine interruption type
bal do_interruption
.align 5
syscall:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 8 ! Determine interruption type
bal do_interruption
.align 5
internal_interrupt:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 9 ! Determine interruption type
bal do_interruption
.align 5
software_interrupt:
SAVE_ALL
move $r0, $sp ! To get the kernel stack
li $r1, 10 ! Determine interruption type
bal do_interruption
.align 5
/*
* void reset_cpu(ulong addr);
* $r0: input address to jump to
*/
.globl reset_cpu
reset_cpu:
/* No need to disable MMU because we never enable it */
bal invalidate_icac
bal invalidate_dcac
mfsr $p0, $MMU_CFG
andi $p0, $p0, 0x3 ! MMPS
li $p1, 0x2 ! TLB MMU
bne $p0, $p1, 1f
tlbop flushall ! Flush TLB
1:
mfsr $p0, MR_CAC_CTL ! Get the $CACHE_CTL reg
li $p1, DIS_DCAC
and $p0, $p0, $p1 ! Clear the DC_EN bit
mtsr $p0, MR_CAC_CTL ! Write back the $CACHE_CTL reg
br $r0 ! Jump to the input address