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Diffstat (limited to 'arch/nds32/cpu/n1213/start.S')
| -rw-r--r-- | arch/nds32/cpu/n1213/start.S | 545 |
1 files changed, 545 insertions, 0 deletions
diff --git a/arch/nds32/cpu/n1213/start.S b/arch/nds32/cpu/n1213/start.S new file mode 100644 index 0000000..558fd0e --- /dev/null +++ b/arch/nds32/cpu/n1213/start.S @@ -0,0 +1,545 @@ +/* + * 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> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <asm-offsets.h> +#include <config.h> +#include <common.h> +#include <asm/macro.h> +#include <version.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: +set_ivb: + li $r0, 0x0 + + /* turn on BTB */ + mtsr $r0, $misc_ctl + /* set IVIC, vector size: 4 bytes, base: 0x0 */ + mtsr $r0, $ivb + +load_lli: +#ifndef CONFIG_SKIP_LOWLEVEL_INIT + jal load_lowlevel_init + jral $p0 +#endif + +/* + * Set the N1213 (Whitiger) core to superuser mode + * According to spec, it is already when reset + */ +turnoff_wtdog: +#ifndef CONFIG_SKIP_TRUNOFF_WATCHDOG + jal load_turnoff_watchdog + jral $p0 +#endif + +/* + * Do CPU critical regs init only at reboot, + * not when booting from ram + */ +#ifdef CONFIG_INIT_CRITICAL + bal 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 $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. + * + */ +.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 + + beq $r0, $r6, clear_bss /* skip relocation */ + + move $r1, $r6 /* r1 <- scratch for copy_loop */ + la $r3, __bss_start + sub $r3, $r3, $r0 /* r3 <- __bss_start_ofs */ + add $r2, $r0, $r3 /* r2 <- source end address */ + +copy_loop: + lwi.p $r7, [$r0], #4 + swi.p $r7, [$r1], #4 + blt $r0, $r2, copy_loop + +/* + * fix relocations related issues + */ +fix_relocations: + l.w $r0, _TEXT_BASE /* r0 <- Text base */ + sub $r9, $r6, $r0 /* r9 <- relocation offset */ + +fix_got: +/* + * Now we want to update GOT. + * + * GOT[0] is reserved. GOT[1] is also reserved for the dynamic object + * generated by GNU ld. Skip these reserved entries from relocation. + */ + la $r2, __got_start /* r2 <- rel __got_start in FLASH */ + add $r2, $r2, $r9 /* r2 <- rel __got_start in RAM */ + la $r3, __got_end /* r3 <- rel __got_end in FLASH */ + add $r3, $r3, $r9 /* r3 <- rel __got_end in RAM */ + addi $r2, $r2, #8 /* skipping first two entries */ +fix_got_loop: + lwi $r0, [$r2] /* r0 <- location in FLASH to fix up */ + add $r0, $r0, $r9 /* r0 <- location fix up to RAM */ + swi.p $r0, [$r2], #4 /* r0 <- store fix into .got in RAM */ + blt $r2, $r3, fix_got_loop + +clear_bss: + la $r0, __bss_start /* r0 <- rel __bss_start in FLASH */ + add $r0, $r0, $r9 /* r0 <- rel __bss_start in FLASH */ + la $r1, __bss_end /* 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 + 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 */ + bal invalidate_icac + bal 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 + +#ifndef CONFIG_SKIP_LOWLEVEL_INIT +load_lowlevel_init: + la $r6, lowlevel_init + la $r7, load_lli + 4 + sub $p0, $r6, $r7 + add $p0, $p0, $lp +ret +#endif + +#ifndef CONFIG_SKIP_TRUNOFF_WATCHDOG +load_turnoff_watchdog: + la $r6, turnoff_watchdog + la $r7, turnoff_wtdog + 4 + sub $p0, $r6, $r7 + add $p0, $p0, $lp +ret +#endif + +/* + * Invalidate I$ + */ +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: + la $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 |
