| /* |
| * CRISv32 kernel startup code. |
| * |
| * Copyright (C) 2003, Axis Communications AB |
| */ |
| |
| |
| #define ASSEMBLER_MACROS_ONLY |
| |
| /* |
| * The macros found in mmu_defs_asm.h uses the ## concatenation operator, so |
| * -traditional must not be used when assembling this file. |
| */ |
| #include <asm/arch/hwregs/reg_rdwr.h> |
| #include <asm/arch/hwregs/asm/mmu_defs_asm.h> |
| #include <asm/arch/hwregs/asm/reg_map_asm.h> |
| #include <asm/arch/hwregs/asm/config_defs_asm.h> |
| #include <asm/arch/hwregs/asm/bif_core_defs_asm.h> |
| |
| #define CRAMFS_MAGIC 0x28cd3d45 |
| #define RAM_INIT_MAGIC 0x56902387 |
| #define COMMAND_LINE_MAGIC 0x87109563 |
| |
| ;; NOTE: R8 and R9 carry information from the decompressor (if the |
| ;; kernel was compressed). They must not be used in the code below |
| ;; until they are read! |
| |
| ;; Exported symbols. |
| .global etrax_irv |
| .global romfs_start |
| .global romfs_length |
| .global romfs_in_flash |
| .global swapper_pg_dir |
| .global crisv32_nand_boot |
| .global crisv32_nand_cramfs_offset |
| |
| ;; Dummy section to make it bootable with current VCS simulator |
| #ifdef CONFIG_ETRAXFS_SIM |
| .section ".boot", "ax" |
| ba tstart |
| nop |
| #endif |
| |
| .text |
| tstart: |
| ;; This is the entry point of the kernel. The CPU is currently in |
| ;; supervisor mode. |
| ;; |
| ;; 0x00000000 if flash. |
| ;; 0x40004000 if DRAM. |
| ;; |
| di |
| |
| ;; Start clocks for used blocks. |
| move.d REG_ADDR(config, regi_config, rw_clk_ctrl), $r1 |
| move.d [$r1], $r0 |
| or.d REG_STATE(config, rw_clk_ctrl, cpu, yes) | \ |
| REG_STATE(config, rw_clk_ctrl, bif, yes) | \ |
| REG_STATE(config, rw_clk_ctrl, fix_io, yes), $r0 |
| move.d $r0, [$r1] |
| |
| ;; Set up waitstates etc |
| move.d REG_ADDR(bif_core, regi_bif_core, rw_grp1_cfg), $r0 |
| move.d CONFIG_ETRAX_MEM_GRP1_CONFIG, $r1 |
| move.d $r1, [$r0] |
| move.d REG_ADDR(bif_core, regi_bif_core, rw_grp2_cfg), $r0 |
| move.d CONFIG_ETRAX_MEM_GRP2_CONFIG, $r1 |
| move.d $r1, [$r0] |
| move.d REG_ADDR(bif_core, regi_bif_core, rw_grp3_cfg), $r0 |
| move.d CONFIG_ETRAX_MEM_GRP3_CONFIG, $r1 |
| move.d $r1, [$r0] |
| move.d REG_ADDR(bif_core, regi_bif_core, rw_grp4_cfg), $r0 |
| move.d CONFIG_ETRAX_MEM_GRP4_CONFIG, $r1 |
| move.d $r1, [$r0] |
| |
| #ifdef CONFIG_ETRAXFS_SIM |
| ;; Set up minimal flash waitstates |
| move.d 0, $r10 |
| move.d REG_ADDR(bif_core, regi_bif_core, rw_grp1_cfg), $r11 |
| move.d $r10, [$r11] |
| #endif |
| |
| ;; Setup and enable the MMU. Use same configuration for both the data |
| ;; and the instruction MMU. |
| ;; |
| ;; Note; 3 cycles is needed for a bank-select to take effect. Further; |
| ;; bank 1 is the instruction MMU, bank 2 is the data MMU. |
| #ifndef CONFIG_ETRAXFS_SIM |
| move.d REG_FIELD(mmu, rw_mm_kbase_hi, base_e, 8) \ |
| | REG_FIELD(mmu, rw_mm_kbase_hi, base_c, 4) \ |
| | REG_FIELD(mmu, rw_mm_kbase_hi, base_b, 0xb), $r0 |
| #else |
| ;; Map the virtual DRAM to the RW eprom area at address 0. |
| ;; Also map 0xa for the hook calls, |
| move.d REG_FIELD(mmu, rw_mm_kbase_hi, base_e, 8) \ |
| | REG_FIELD(mmu, rw_mm_kbase_hi, base_c, 0) \ |
| | REG_FIELD(mmu, rw_mm_kbase_hi, base_b, 0xb) \ |
| | REG_FIELD(mmu, rw_mm_kbase_hi, base_a, 0xa), $r0 |
| #endif |
| |
| ;; Temporary map of 0x40 -> 0x40 and 0x00 -> 0x00. |
| move.d REG_FIELD(mmu, rw_mm_kbase_lo, base_4, 4) \ |
| | REG_FIELD(mmu, rw_mm_kbase_lo, base_0, 0), $r1 |
| |
| ;; Enable certain page protections and setup linear mapping |
| ;; for f,e,c,b,4,0. |
| #ifndef CONFIG_ETRAXFS_SIM |
| move.d REG_STATE(mmu, rw_mm_cfg, we, on) \ |
| | REG_STATE(mmu, rw_mm_cfg, acc, on) \ |
| | REG_STATE(mmu, rw_mm_cfg, ex, on) \ |
| | REG_STATE(mmu, rw_mm_cfg, inv, on) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_f, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_e, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_d, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_c, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_b, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_a, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_9, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_8, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_7, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_6, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_5, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_4, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_3, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_2, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_1, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_0, linear), $r2 |
| #else |
| move.d REG_STATE(mmu, rw_mm_cfg, we, on) \ |
| | REG_STATE(mmu, rw_mm_cfg, acc, on) \ |
| | REG_STATE(mmu, rw_mm_cfg, ex, on) \ |
| | REG_STATE(mmu, rw_mm_cfg, inv, on) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_f, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_e, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_d, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_c, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_b, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_a, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_9, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_8, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_7, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_6, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_5, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_4, linear) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_3, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_2, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_1, page) \ |
| | REG_STATE(mmu, rw_mm_cfg, seg_0, linear), $r2 |
| #endif |
| |
| ;; Update instruction MMU. |
| move 1, $srs |
| nop |
| nop |
| nop |
| move $r0, $s2 ; kbase_hi. |
| move $r1, $s1 ; kbase_lo. |
| move $r2, $s0 ; mm_cfg, virtual memory configuration. |
| |
| ;; Update data MMU. |
| move 2, $srs |
| nop |
| nop |
| nop |
| move $r0, $s2 ; kbase_hi. |
| move $r1, $s1 ; kbase_lo |
| move $r2, $s0 ; mm_cfg, virtual memory configuration. |
| |
| ;; Enable data and instruction MMU. |
| move 0, $srs |
| moveq 0xf, $r0 ; IMMU, DMMU, DCache, Icache on |
| nop |
| nop |
| nop |
| move $r0, $s0 |
| nop |
| nop |
| nop |
| |
| #ifdef CONFIG_SMP |
| ;; Read CPU ID |
| move 0, $srs |
| nop |
| nop |
| nop |
| move $s10, $r0 |
| cmpq 0, $r0 |
| beq master_cpu |
| nop |
| slave_cpu: |
| ; A slave waits for cpu_now_booting to be equal to CPU ID. |
| move.d cpu_now_booting, $r1 |
| slave_wait: |
| cmp.d [$r1], $r0 |
| bne slave_wait |
| nop |
| ; Time to boot-up. Get stack location provided by master CPU. |
| move.d smp_init_current_idle_thread, $r1 |
| move.d [$r1], $sp |
| add.d 8192, $sp |
| move.d ebp_start, $r0 ; Defined in linker-script. |
| move $r0, $ebp |
| jsr smp_callin |
| nop |
| master_cpu: |
| #endif |
| #ifndef CONFIG_ETRAXFS_SIM |
| ;; Check if starting from DRAM or flash. |
| lapcq ., $r0 |
| and.d 0x7fffffff, $r0 ; Mask off the non-cache bit. |
| cmp.d 0x10000, $r0 ; Arbitrary, something above this code. |
| blo _inflash0 |
| nop |
| #endif |
| |
| jump _inram ; Jump to cached RAM. |
| nop |
| |
| ;; Jumpgate. |
| _inflash0: |
| jump _inflash |
| nop |
| |
| ;; Put the following in a section so that storage for it can be |
| ;; reclaimed after init is finished. |
| .section ".init.text", "ax" |
| |
| _inflash: |
| |
| ;; Initialize DRAM. |
| cmp.d RAM_INIT_MAGIC, $r8 ; Already initialized? |
| beq _dram_initialized |
| nop |
| |
| #include "../lib/dram_init.S" |
| |
| _dram_initialized: |
| ;; Copy the text and data section to DRAM. This depends on that the |
| ;; variables used below are correctly set up by the linker script. |
| ;; The calculated value stored in R4 is used below. |
| moveq 0, $r0 ; Source. |
| move.d text_start, $r1 ; Destination. |
| move.d __vmlinux_end, $r2 |
| move.d $r2, $r4 |
| sub.d $r1, $r4 |
| 1: move.w [$r0+], $r3 |
| move.w $r3, [$r1+] |
| cmp.d $r2, $r1 |
| blo 1b |
| nop |
| |
| ;; Keep CRAMFS in flash. |
| moveq 0, $r0 |
| move.d romfs_length, $r1 |
| move.d $r0, [$r1] |
| move.d [$r4], $r0 ; cramfs_super.magic |
| cmp.d CRAMFS_MAGIC, $r0 |
| bne 1f |
| nop |
| |
| addoq +4, $r4, $acr |
| move.d [$acr], $r0 |
| move.d romfs_length, $r1 |
| move.d $r0, [$r1] |
| add.d 0xf0000000, $r4 ; Add cached flash start in virtual memory. |
| move.d romfs_start, $r1 |
| move.d $r4, [$r1] |
| 1: moveq 1, $r0 |
| move.d romfs_in_flash, $r1 |
| move.d $r0, [$r1] |
| |
| jump _start_it ; Jump to cached code. |
| nop |
| |
| _inram: |
| ;; Check if booting from NAND flash (in that case we just remember the offset |
| ;; into the flash where cramfs should be). |
| move.d REG_ADDR(config, regi_config, r_bootsel), $r0 |
| move.d [$r0], $r0 |
| and.d REG_MASK(config, r_bootsel, boot_mode), $r0 |
| cmp.d REG_STATE(config, r_bootsel, boot_mode, nand), $r0 |
| bne move_cramfs |
| moveq 1,$r0 |
| move.d crisv32_nand_boot, $r1 |
| move.d $r0, [$r1] |
| move.d crisv32_nand_cramfs_offset, $r1 |
| move.d $r9, [$r1] |
| moveq 1, $r0 |
| move.d romfs_in_flash, $r1 |
| move.d $r0, [$r1] |
| jump _start_it |
| nop |
| |
| move_cramfs: |
| ;; Move the cramfs after BSS. |
| moveq 0, $r0 |
| move.d romfs_length, $r1 |
| move.d $r0, [$r1] |
| |
| #ifndef CONFIG_ETRAXFS_SIM |
| ;; The kernel could have been unpacked to DRAM by the loader, but |
| ;; the cramfs image could still be inte the flash immediately |
| ;; following the compressed kernel image. The loaded passes the address |
| ;; of the bute succeeding the last compressed byte in the flash in |
| ;; register R9 when starting the kernel. |
| cmp.d 0x0ffffff8, $r9 |
| bhs _no_romfs_in_flash ; R9 points outside the flash area. |
| nop |
| #else |
| ba _no_romfs_in_flash |
| nop |
| #endif |
| move.d [$r9], $r0 ; cramfs_super.magic |
| cmp.d CRAMFS_MAGIC, $r0 |
| bne _no_romfs_in_flash |
| nop |
| |
| addoq +4, $r9, $acr |
| move.d [$acr], $r0 |
| move.d romfs_length, $r1 |
| move.d $r0, [$r1] |
| add.d 0xf0000000, $r9 ; Add cached flash start in virtual memory. |
| move.d romfs_start, $r1 |
| move.d $r9, [$r1] |
| moveq 1, $r0 |
| move.d romfs_in_flash, $r1 |
| move.d $r0, [$r1] |
| |
| jump _start_it ; Jump to cached code. |
| nop |
| |
| _no_romfs_in_flash: |
| ;; Look for cramfs. |
| #ifndef CONFIG_ETRAXFS_SIM |
| move.d __vmlinux_end, $r0 |
| #else |
| move.d __end, $r0 |
| #endif |
| move.d [$r0], $r1 |
| cmp.d CRAMFS_MAGIC, $r1 |
| bne 2f |
| nop |
| |
| addoq +4, $r0, $acr |
| move.d [$acr], $r2 |
| move.d _end, $r1 |
| move.d romfs_start, $r3 |
| move.d $r1, [$r3] |
| move.d romfs_length, $r3 |
| move.d $r2, [$r3] |
| |
| #ifndef CONFIG_ETRAXFS_SIM |
| add.d $r2, $r0 |
| add.d $r2, $r1 |
| |
| lsrq 1, $r2 ; Size is in bytes, we copy words. |
| addq 1, $r2 |
| 1: |
| move.w [$r0], $r3 |
| move.w $r3, [$r1] |
| subq 2, $r0 |
| subq 2, $r1 |
| subq 1, $r2 |
| bne 1b |
| nop |
| #endif |
| |
| 2: |
| moveq 0, $r0 |
| move.d romfs_in_flash, $r1 |
| move.d $r0, [$r1] |
| |
| jump _start_it ; Jump to cached code. |
| nop |
| |
| _start_it: |
| |
| ;; Check if kernel command line is supplied |
| cmp.d COMMAND_LINE_MAGIC, $r10 |
| bne no_command_line |
| nop |
| |
| move.d 256, $r13 |
| move.d cris_command_line, $r10 |
| or.d 0x80000000, $r11 ; Make it virtual |
| 1: |
| move.b [$r11+], $r12 |
| move.b $r12, [$r10+] |
| subq 1, $r13 |
| bne 1b |
| nop |
| |
| no_command_line: |
| |
| ;; The kernel stack contains a task structure for each task. This |
| ;; the initial kernel stack is in the same page as the init_task, |
| ;; but starts at the top of the page, i.e. + 8192 bytes. |
| move.d init_thread_union + 8192, $sp |
| move.d ebp_start, $r0 ; Defined in linker-script. |
| move $r0, $ebp |
| move.d etrax_irv, $r1 ; Set the exception base register and pointer. |
| move.d $r0, [$r1] |
| |
| #ifndef CONFIG_ETRAXFS_SIM |
| ;; Clear the BSS region from _bss_start to _end. |
| move.d __bss_start, $r0 |
| move.d _end, $r1 |
| 1: clear.d [$r0+] |
| cmp.d $r1, $r0 |
| blo 1b |
| nop |
| #endif |
| |
| #ifdef CONFIG_ETRAXFS_SIM |
| /* Set the watchdog timeout to something big. Will be removed when */ |
| /* watchdog can be disabled with command line option */ |
| move.d 0x7fffffff, $r10 |
| jsr CPU_WATCHDOG_TIMEOUT |
| nop |
| #endif |
| |
| ; Initialize registers to increase determinism |
| move.d __bss_start, $r0 |
| movem [$r0], $r13 |
| |
| jump start_kernel ; Jump to start_kernel() in init/main.c. |
| nop |
| |
| .data |
| etrax_irv: |
| .dword 0 |
| romfs_start: |
| .dword 0 |
| romfs_length: |
| .dword 0 |
| romfs_in_flash: |
| .dword 0 |
| crisv32_nand_boot: |
| .dword 0 |
| crisv32_nand_cramfs_offset: |
| .dword 0 |
| |
| swapper_pg_dir = 0xc0002000 |
| |
| .section ".init.data", "aw" |
| |
| #include "../lib/hw_settings.S" |
