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2b0e86cc5d
This patch add support to boot kernel from places other than KERNELBASE. Since CONFIG_RELOCATABLE has already supported, what we need to do is map or copy kernel to a proper place and relocate. Freescale Book-E parts expect lowmem to be mapped by fixed TLB entries(TLB1). The TLB1 entries are not suitable to map the kernel directly in a randomized region, so we chose to copy the kernel to a proper place and restart to relocate. The offset of the kernel was not randomized yet(a fixed 64M is set). We will randomize it in the next patch. Signed-off-by: Jason Yan <yanaijie@huawei.com> Tested-by: Diana Craciun <diana.craciun@nxp.com> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net> [mpe: Use PTRRELOC() in early_init()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
39 lines
920 B
C
39 lines
920 B
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Early init before relocation
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*/
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <asm/setup.h>
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#include <asm/sections.h>
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#include <asm/asm-prototypes.h>
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/*
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* We're called here very early in the boot.
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*
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* Note that the kernel may be running at an address which is different
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* from the address that it was linked at, so we must use RELOC/PTRRELOC
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* to access static data (including strings). -- paulus
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*/
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notrace unsigned long __init early_init(unsigned long dt_ptr)
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{
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unsigned long kva, offset = reloc_offset();
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kva = *PTRRELOC(&kernstart_virt_addr);
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/* First zero the BSS */
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if (kva == KERNELBASE)
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memset(PTRRELOC(&__bss_start), 0, __bss_stop - __bss_start);
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/*
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* Identify the CPU type and fix up code sections
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* that depend on which cpu we have.
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*/
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identify_cpu(offset, mfspr(SPRN_PVR));
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apply_feature_fixups();
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return kva + offset;
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}
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