u-boot/arch/xtensa/cpu/u-boot.lds
Chris Zankel c978b52410 xtensa: add support for the xtensa processor architecture [2/2]
The Xtensa processor architecture is a configurable, extensible,
and synthesizable 32-bit RISC processor core provided by Tensilica, inc.

This is the second part of the basic architecture port, adding the
'arch/xtensa' directory and a readme file.

Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
2016-08-15 18:46:38 -04:00

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/*
* (C) Copyright 2008 - 2013 Tensilica, Inc.
* (C) Copyright 2014 - 2016 Cadence Design Systems Inc.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <config.h>
#include <asm/ldscript.h>
#include <asm/arch/core.h>
#include <asm/addrspace.h>
#include <asm-offsets.h>
OUTPUT_ARCH(xtensa)
ENTRY(_start)
/*
* U-Boot resets from SYSROM and unpacks itself from a ROM store to RAM.
* The reset vector is usually near the base of SYSROM and has room
* above it for the ROM store into which the rest of U-Boot is packed.
* The ROM store also needs to be above any other vectors that are in ROM.
* If a core has its vectors near the top of ROM, this must be edited.
*
* Note that to run C code out of ROM, the processor would have to support
* 'relocatable' exception vectors and provide a scratch memory for the
* initial stack. Not all Xtensa processor configurations support that, so
* we can simplify the boot process and unpack U-Boot to RAM immediately.
* This, however, requires that memory have been initialized throug some
* other means (serial ROM, for example) or are initialized early (requiring
* an assembler function. See start.S for more details)
*/
SECTIONS
{
. = + SIZEOF_HEADERS;
SECTION_ResetVector(XCHAL_RESET_VECTOR_VADDR, LMA_EQ_VMA)
.reloc_table ALIGN(4) : FOLLOWING(.ResetVector.text)
{
__reloc_table_start = ABSOLUTE(.);
#if XCHAL_HAVE_WINDOWED
RELOCATE2(WindowVectors,text);
#endif
RELOCATE2(KernelExceptionVector,literal);
RELOCATE2(KernelExceptionVector,text);
RELOCATE2(UserExceptionVector,literal);
RELOCATE2(UserExceptionVector,text);
RELOCATE2(DoubleExceptionVector,literal);
RELOCATE2(DoubleExceptionVector,text);
RELOCATE1(text);
RELOCATE1(rodata);
RELOCATE1(data);
RELOCATE1(u_boot_list);
__reloc_table_end = ABSOLUTE(.);
}
#if XCHAL_HAVE_WINDOWED
SECTION_VECTOR(WindowVectors,text,XCHAL_WINDOW_VECTORS_VADDR,
FOLLOWING(.reloc_table))
SECTION_VECTOR(KernelExceptionVector,literal,XCHAL_KERNEL_VECTOR_VADDR-8,
FOLLOWING(.WindowVectors.text))
#else
SECTION_VECTOR(KernelExceptionVector,literal,XCHAL_KERNEL_VECTOR_VADDR-8,
FOLLOWING(.reloc_table))
#endif
SECTION_VECTOR(KernelExceptionVector,text,XCHAL_KERNEL_VECTOR_VADDR,
FOLLOWING(.KernelExceptionVector.literal))
SECTION_VECTOR(UserExceptionVector,literal,XCHAL_USER_VECTOR_VADDR-8,
FOLLOWING(.KernelExceptionVector.text))
SECTION_VECTOR(UserExceptionVector,text,XCHAL_USER_VECTOR_VADDR,
FOLLOWING(.UserExceptionVector.literal))
SECTION_VECTOR(DoubleExceptionVector,literal,XCHAL_DOUBLEEXC_VECTOR_VADDR-8,
FOLLOWING(.UserExceptionVector.text))
SECTION_VECTOR(DoubleExceptionVector,text,XCHAL_DOUBLEEXC_VECTOR_VADDR,
FOLLOWING(.DoubleExceptionVector.literal))
__monitor_start = CONFIG_SYS_TEXT_ADDR;
SECTION_text(CONFIG_SYS_TEXT_ADDR, FOLLOWING(.DoubleExceptionVector.text))
SECTION_rodata(ALIGN(16), FOLLOWING(.text))
SECTION_u_boot_list(ALIGN(16), FOLLOWING(.rodata))
SECTION_data(ALIGN(16), FOLLOWING(.u_boot_list))
__reloc_end = .;
__init_end = .;
SECTION_bss(__init_end (OVERLAY),)
__monitor_end = .;
/*
* On many Xtensa boards a region of RAM may be mapped to the ROM address
* space to facilitate on-chip-debug, and U-Boot must fit with that region.
* The config variables CONFIG_SYS_MONITOR_* define the region.
* If U-Boot extends beyond this region it will appear discontiguous in the
* address space and is in danger of overwriting itself during unpacking
* ("relocation").
* This causes U-Boot to crash in a way that is difficult to debug. On some
* boards (such as xtav60) the region is small enough that U-Boot will not
* fit if compiled entirely with -O0 (a common scenario). To avoid a lengthy
* debugging session when this happens, ensure a link-time error occurs.
*
*/
ASSERT(__monitor_end - __monitor_start <= CONFIG_SYS_MONITOR_LEN,
"U-Boot ROM image is too large. Check optimization level.")
SECTION_xtensa
SECTION_debug
/DISCARD/ : { *(.dynstr*) }
/DISCARD/ : { *(.hash*) }
/DISCARD/ : { *(.interp) }
/DISCARD/ : { *(.got*) }
/DISCARD/ : { *(.dynsym) }
}