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https://github.com/brain-hackers/u-boot-brain
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![Tom Rini](/assets/img/avatar_default.png)
When U-Boot started using SPDX tags we were among the early adopters and there weren't a lot of other examples to borrow from. So we picked the area of the file that usually had a full license text and replaced it with an appropriate SPDX-License-Identifier: entry. Since then, the Linux Kernel has adopted SPDX tags and they place it as the very first line in a file (except where shebangs are used, then it's second line) and with slightly different comment styles than us. In part due to community overlap, in part due to better tag visibility and in part for other minor reasons, switch over to that style. This commit changes all instances where we have a single declared license in the tag as both the before and after are identical in tag contents. There's also a few places where I found we did not have a tag and have introduced one. Signed-off-by: Tom Rini <trini@konsulko.com>
180 lines
4.2 KiB
ArmAsm
180 lines
4.2 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0+ */
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/*
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* (C) Copyright 2004, Psyent Corporation <www.psyent.com>
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* Scott McNutt <smcnutt@psyent.com>
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*/
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#include <asm-offsets.h>
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#include <config.h>
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#include <version.h>
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/*
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* icache and dcache configuration used only for start.S.
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* the values are chosen so that it will work for all configuration.
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*/
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#define ICACHE_LINE_SIZE 32 /* fixed 32 */
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#define ICACHE_SIZE_MAX 0x10000 /* 64k max */
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#define DCACHE_LINE_SIZE_MIN 4 /* 4, 16, 32 */
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#define DCACHE_SIZE_MAX 0x10000 /* 64k max */
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/* RESTART */
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.text
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.global _start, _except_start, _except_end
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_start:
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wrctl status, r0 /* Disable interrupts */
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/*
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* ICACHE INIT -- only the icache line at the reset address
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* is invalidated at reset. So the init must stay within
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* the cache line size (8 words). If GERMS is used, we'll
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* just be invalidating the cache a second time. If cache
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* is not implemented initi behaves as nop.
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*/
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ori r4, r0, %lo(ICACHE_LINE_SIZE)
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movhi r5, %hi(ICACHE_SIZE_MAX)
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ori r5, r5, %lo(ICACHE_SIZE_MAX)
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0: initi r5
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sub r5, r5, r4
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bgt r5, r0, 0b
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br _except_end /* Skip the tramp */
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/*
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* EXCEPTION TRAMPOLINE -- the following gets copied
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* to the exception address (below), but is otherwise at the
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* default exception vector offset (0x0020).
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*/
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_except_start:
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movhi et, %hi(_exception)
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ori et, et, %lo(_exception)
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jmp et
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_except_end:
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/*
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* INTERRUPTS -- for now, all interrupts masked and globally
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* disabled.
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*/
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wrctl ienable, r0 /* All disabled */
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/*
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* DCACHE INIT -- if dcache not implemented, initd behaves as
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* nop.
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*/
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ori r4, r0, %lo(DCACHE_LINE_SIZE_MIN)
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movhi r5, %hi(DCACHE_SIZE_MAX)
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ori r5, r5, %lo(DCACHE_SIZE_MAX)
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mov r6, r0
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1: initd 0(r6)
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add r6, r6, r4
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bltu r6, r5, 1b
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/*
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* RELOCATE CODE, DATA & COMMAND TABLE -- the following code
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* assumes code, data and the command table are all
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* contiguous. This lets us relocate everything as a single
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* block. Make sure the linker script matches this ;-)
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*/
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nextpc r4
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_cur: movhi r5, %hi(_cur - _start)
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ori r5, r5, %lo(_cur - _start)
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sub r4, r4, r5 /* r4 <- cur _start */
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mov r8, r4
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movhi r5, %hi(_start)
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ori r5, r5, %lo(_start) /* r5 <- linked _start */
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mov sp, r5 /* initial stack below u-boot code */
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beq r4, r5, 3f
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movhi r6, %hi(CONFIG_SYS_MONITOR_LEN)
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ori r6, r6, %lo(CONFIG_SYS_MONITOR_LEN)
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add r6, r6, r5
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2: ldwio r7, 0(r4)
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addi r4, r4, 4
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stwio r7, 0(r5)
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addi r5, r5, 4
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bne r5, r6, 2b
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3:
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/* JUMP TO RELOC ADDR */
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movhi r4, %hi(_reloc)
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ori r4, r4, %lo(_reloc)
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jmp r4
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_reloc:
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/* STACK INIT -- zero top two words for call back chain. */
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addi sp, sp, -8
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stw r0, 0(sp)
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stw r0, 4(sp)
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mov fp, sp
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#ifdef CONFIG_DEBUG_UART
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/* Set up the debug UART */
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movhi r2, %hi(debug_uart_init@h)
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ori r2, r2, %lo(debug_uart_init@h)
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callr r2
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#endif
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/* Allocate and initialize reserved area, update SP */
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mov r4, sp
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movhi r2, %hi(board_init_f_alloc_reserve@h)
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ori r2, r2, %lo(board_init_f_alloc_reserve@h)
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callr r2
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mov sp, r2
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mov r4, sp
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movhi r2, %hi(board_init_f_init_reserve@h)
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ori r2, r2, %lo(board_init_f_init_reserve@h)
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callr r2
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/* Update frame-pointer */
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mov fp, sp
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/* Call board_init_f -- never returns */
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mov r4, r0
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movhi r2, %hi(board_init_f@h)
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ori r2, r2, %lo(board_init_f@h)
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callr r2
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/*
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* NEVER RETURNS -- but branch to the _start just
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* in case ;-)
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*/
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br _start
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/*
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* relocate_code -- Nios2 handles the relocation above. But
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* the generic board code monkeys with the heap, stack, etc.
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* (it makes some assumptions that may not be appropriate
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* for Nios). Nevertheless, we capitulate here.
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*
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* We'll call the board_init_r from here since this isn't
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* supposed to return.
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*
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* void relocate_code (ulong sp, gd_t *global_data,
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* ulong reloc_addr)
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* __attribute__ ((noreturn));
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*/
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.text
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.global relocate_code
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relocate_code:
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mov sp, r4 /* Set the new sp */
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mov r4, r5
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/*
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* ZERO BSS/SBSS -- bss and sbss are assumed to be adjacent
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* and between __bss_start and __bss_end.
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*/
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movhi r5, %hi(__bss_start)
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ori r5, r5, %lo(__bss_start)
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movhi r6, %hi(__bss_end)
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ori r6, r6, %lo(__bss_end)
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beq r5, r6, 5f
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4: stw r0, 0(r5)
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addi r5, r5, 4
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bne r5, r6, 4b
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5:
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movhi r8, %hi(board_init_r@h)
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ori r8, r8, %lo(board_init_r@h)
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callr r8
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ret
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