| Message ID | 1447943047-22427-1-git-send-email-chris.brandt@renesas.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 2015-11-19 15:24, Chris Brandt wrote: > When building an XIP kernel, the linker script needs to be much different > than a conventional kernel's script. Over time, it's been difficult to > maintain both XIP and non-XIP layouts in one linker script. Therefore, > this patch separates the two procedures into two completely different > files. > > The new linker script is essentially a straight copy of the current script > with all the non-CONFIG_XIP_KERNEL portions removed. > > Additionally, all CONFIG_XIP_KERNEL portions have been removed from the > existing linker script...never to return again. > > From now on, for any architecture, when CONFIG_XIP_KERNEL is enabled, you > must provide a vmlinux-xip.lds.S for the build process. Why not have a vmlinux.lds.S and #include a vmlinux-xip.lds.S / vmlinux-nonxip.lds.S from there? That way, you do not clutter the main Makefile and you can reuse the boilerplate of the linker script. Michal
On Thu, 19 Nov 2015, Chris Brandt wrote: > When building an XIP kernel, the linker script needs to be much different > than a conventional kernel's script. Over time, it's been difficult to > maintain both XIP and non-XIP layouts in one linker script. Therefore, > this patch separates the two procedures into two completely different > files. > > The new linker script is essentially a straight copy of the current script > with all the non-CONFIG_XIP_KERNEL portions removed. > > Additionally, all CONFIG_XIP_KERNEL portions have been removed from the > existing linker script...never to return again. Would be worth mentioning that XIP is still broken and this is just the first move to fix it properly with subsequent patches. > From now on, for any architecture, when CONFIG_XIP_KERNEL is enabled, you > must provide a vmlinux-xip.lds.S for the build process. I agree with Michal's suggestion to do the selection locally with an include. This could be commonalized in the main makefile if many architecturs come to have XIP support. > > Signed-off-by: Chris Brandt <chris.brandt@renesas.com> > --- > Makefile | 4 + > arch/arm/kernel/.gitignore | 1 + > arch/arm/kernel/vmlinux-xip.lds.S | 322 +++++++++++++++++++++++++++++++++++++ > arch/arm/kernel/vmlinux.lds.S | 31 +--- > 4 files changed, 331 insertions(+), 27 deletions(-) > create mode 100644 arch/arm/kernel/vmlinux-xip.lds.S > > diff --git a/Makefile b/Makefile > index 3a0234f..b55440f 100644 > --- a/Makefile > +++ b/Makefile > @@ -900,7 +900,11 @@ virt-y := $(patsubst %/, %/built-in.o, $(virt-y)) > # Externally visible symbols (used by link-vmlinux.sh) > export KBUILD_VMLINUX_INIT := $(head-y) $(init-y) > export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y) $(virt-y) > +ifdef CONFIG_XIP_KERNEL > +export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux-xip.lds > +else > export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds > +endif > export LDFLAGS_vmlinux > # used by scripts/pacmage/Makefile > export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools) > diff --git a/arch/arm/kernel/.gitignore b/arch/arm/kernel/.gitignore > index c5f676c..522c636 100644 > --- a/arch/arm/kernel/.gitignore > +++ b/arch/arm/kernel/.gitignore > @@ -1 +1,2 @@ > vmlinux.lds > +vmlinux-xip.lds > diff --git a/arch/arm/kernel/vmlinux-xip.lds.S b/arch/arm/kernel/vmlinux-xip.lds.S > new file mode 100644 > index 0000000..1fd938d > --- /dev/null > +++ b/arch/arm/kernel/vmlinux-xip.lds.S > @@ -0,0 +1,322 @@ > +/* ld script to make ARM Linux kernel > + * taken from the i386 version by Russell King > + * Written by Martin Mares <mj@atrey.karlin.mff.cuni.cz> > + */ > + > +#include <asm-generic/vmlinux.lds.h> > +#include <asm/cache.h> > +#include <asm/thread_info.h> > +#include <asm/memory.h> > +#include <asm/page.h> > +#ifdef CONFIG_ARM_KERNMEM_PERMS > +#include <asm/pgtable.h> > +#endif > + > +#define PROC_INFO \ > + . = ALIGN(4); \ > + VMLINUX_SYMBOL(__proc_info_begin) = .; \ > + *(.proc.info.init) \ > + VMLINUX_SYMBOL(__proc_info_end) = .; > + > +#define IDMAP_TEXT \ > + ALIGN_FUNCTION(); \ > + VMLINUX_SYMBOL(__idmap_text_start) = .; \ > + *(.idmap.text) \ > + VMLINUX_SYMBOL(__idmap_text_end) = .; \ > + . = ALIGN(PAGE_SIZE); \ > + VMLINUX_SYMBOL(__hyp_idmap_text_start) = .; \ > + *(.hyp.idmap.text) \ > + VMLINUX_SYMBOL(__hyp_idmap_text_end) = .; > + > +#ifdef CONFIG_HOTPLUG_CPU > +#define ARM_CPU_DISCARD(x) > +#define ARM_CPU_KEEP(x) x > +#else > +#define ARM_CPU_DISCARD(x) x > +#define ARM_CPU_KEEP(x) > +#endif > + > +#if (defined(CONFIG_SMP_ON_UP) && !defined(CONFIG_DEBUG_SPINLOCK)) || \ > + defined(CONFIG_GENERIC_BUG) > +#define ARM_EXIT_KEEP(x) x > +#define ARM_EXIT_DISCARD(x) > +#else > +#define ARM_EXIT_KEEP(x) > +#define ARM_EXIT_DISCARD(x) x > +#endif > + > +OUTPUT_ARCH(arm) > +ENTRY(stext) > + > +#ifndef __ARMEB__ > +jiffies = jiffies_64; > +#else > +jiffies = jiffies_64 + 4; > +#endif > + > +SECTIONS > +{ > + /* > + * XXX: The linker does not define how output sections are > + * assigned to input sections when there are multiple statements > + * matching the same input section name. There is no documented > + * order of matching. > + * > + * unwind exit sections must be discarded before the rest of the > + * unwind sections get included. > + */ > + /DISCARD/ : { > + *(.ARM.exidx.exit.text) > + *(.ARM.extab.exit.text) > + ARM_CPU_DISCARD(*(.ARM.exidx.cpuexit.text)) > + ARM_CPU_DISCARD(*(.ARM.extab.cpuexit.text)) > + ARM_EXIT_DISCARD(EXIT_TEXT) > + ARM_EXIT_DISCARD(EXIT_DATA) > + EXIT_CALL > +#ifndef CONFIG_MMU > + *(.text.fixup) > + *(__ex_table) > +#endif > +#ifndef CONFIG_SMP_ON_UP > + *(.alt.smp.init) > +#endif > + *(.discard) > + *(.discard.*) > + } > + > + . = XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR); > + > + .head.text : { > + _text = .; > + HEAD_TEXT > + } > + > +#ifdef CONFIG_ARM_KERNMEM_PERMS > + . = ALIGN(1<<SECTION_SHIFT); > +#endif > + > + .text : { /* Real text segment */ > + _stext = .; /* Text and read-only data */ > + IDMAP_TEXT > + __exception_text_start = .; > + *(.exception.text) > + __exception_text_end = .; > + IRQENTRY_TEXT > + TEXT_TEXT > + SCHED_TEXT > + LOCK_TEXT > + KPROBES_TEXT > + *(.gnu.warning) > + *(.glue_7) > + *(.glue_7t) > + . = ALIGN(4); > + *(.got) /* Global offset table */ > + ARM_CPU_KEEP(PROC_INFO) > + } > + > +#ifdef CONFIG_DEBUG_RODATA > + . = ALIGN(1<<SECTION_SHIFT); > +#endif > + RO_DATA(PAGE_SIZE) > + > + . = ALIGN(4); > + __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { > + __start___ex_table = .; > +#ifdef CONFIG_MMU > + *(__ex_table) > +#endif > + __stop___ex_table = .; > + } > + > +#ifdef CONFIG_ARM_UNWIND > + /* > + * Stack unwinding tables > + */ > + . = ALIGN(8); > + .ARM.unwind_idx : { > + __start_unwind_idx = .; > + *(.ARM.exidx*) > + __stop_unwind_idx = .; > + } > + .ARM.unwind_tab : { > + __start_unwind_tab = .; > + *(.ARM.extab*) > + __stop_unwind_tab = .; > + } > +#endif > + > + NOTES > + > + _etext = .; /* End of text and rodata section */ > + > + /* > + * The vectors and stubs are relocatable code, and the > + * only thing that matters is their relative offsets > + */ > + __vectors_start = .; > + .vectors 0 : AT(__vectors_start) { > + *(.vectors) > + } > + . = __vectors_start + SIZEOF(.vectors); > + __vectors_end = .; > + > + __stubs_start = .; > + .stubs 0x1000 : AT(__stubs_start) { > + *(.stubs) > + } > + . = __stubs_start + SIZEOF(.stubs); > + __stubs_end = .; > + > + INIT_TEXT_SECTION(8) > + .exit.text : { > + ARM_EXIT_KEEP(EXIT_TEXT) > + } > + .init.proc.info : { > + ARM_CPU_DISCARD(PROC_INFO) > + } > + .init.arch.info : { > + __arch_info_begin = .; > + *(.arch.info.init) > + __arch_info_end = .; > + } > + .init.tagtable : { > + __tagtable_begin = .; > + *(.taglist.init) > + __tagtable_end = .; > + } > +#ifdef CONFIG_SMP_ON_UP > + .init.smpalt : { > + __smpalt_begin = .; > + *(.alt.smp.init) > + __smpalt_end = .; > + } > +#endif > + .init.pv_table : { > + __pv_table_begin = .; > + *(.pv_table) > + __pv_table_end = .; > + } > + .init.data : { > + INIT_SETUP(16) > + INIT_CALLS > + CON_INITCALL > + SECURITY_INITCALL > + INIT_RAM_FS > + } > + > +#ifdef CONFIG_SMP > + PERCPU_SECTION(L1_CACHE_BYTES) > +#endif > + > + __data_loc = ALIGN(4); /* location in binary */ > + . = PAGE_OFFSET + TEXT_OFFSET; > + > + .data : AT(__data_loc) { > + _data = .; /* address in memory */ > + _sdata = .; > + > + /* > + * first, the init task union, aligned > + * to an 8192 byte boundary. > + */ > + INIT_TASK_DATA(THREAD_SIZE) > + > + . = ALIGN(PAGE_SIZE); > + __init_begin = .; > + INIT_DATA > + ARM_EXIT_KEEP(EXIT_DATA) > + . = ALIGN(PAGE_SIZE); > + __init_end = .; > + > + NOSAVE_DATA > + CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES) > + READ_MOSTLY_DATA(L1_CACHE_BYTES) > + > + /* > + * and the usual data section > + */ > + DATA_DATA > + CONSTRUCTORS > + > + _edata = .; > + } > + _edata_loc = __data_loc + SIZEOF(.data); > + > +#ifdef CONFIG_HAVE_TCM > + /* > + * We align everything to a page boundary so we can > + * free it after init has commenced and TCM contents have > + * been copied to its destination. > + */ > + .tcm_start : { > + . = ALIGN(PAGE_SIZE); > + __tcm_start = .; > + __itcm_start = .; > + } > + > + /* > + * Link these to the ITCM RAM > + * Put VMA to the TCM address and LMA to the common RAM > + * and we'll upload the contents from RAM to TCM and free > + * the used RAM after that. > + */ > + .text_itcm ITCM_OFFSET : AT(__itcm_start) > + { > + __sitcm_text = .; > + *(.tcm.text) > + *(.tcm.rodata) > + . = ALIGN(4); > + __eitcm_text = .; > + } > + > + /* > + * Reset the dot pointer, this is needed to create the > + * relative __dtcm_start below (to be used as extern in code). > + */ > + . = ADDR(.tcm_start) + SIZEOF(.tcm_start) + SIZEOF(.text_itcm); > + > + .dtcm_start : { > + __dtcm_start = .; > + } > + > + /* TODO: add remainder of ITCM as well, that can be used for data! */ > + .data_dtcm DTCM_OFFSET : AT(__dtcm_start) > + { > + . = ALIGN(4); > + __sdtcm_data = .; > + *(.tcm.data) > + . = ALIGN(4); > + __edtcm_data = .; > + } > + > + /* Reset the dot pointer or the linker gets confused */ > + . = ADDR(.dtcm_start) + SIZEOF(.data_dtcm); > + > + /* End marker for freeing TCM copy in linked object */ > + .tcm_end : AT(ADDR(.dtcm_start) + SIZEOF(.data_dtcm)){ > + . = ALIGN(PAGE_SIZE); > + __tcm_end = .; > + } > +#endif > + > + BSS_SECTION(0, 0, 0) > + _end = .; > + > + STABS_DEBUG > +} > + > +/* > + * These must never be empty > + * If you have to comment these two assert statements out, your > + * binutils is too old (for other reasons as well) > + */ > +ASSERT((__proc_info_end - __proc_info_begin), "missing CPU support") > +ASSERT((__arch_info_end - __arch_info_begin), "no machine record defined") > + > +/* > + * The HYP init code can't be more than a page long, > + * and should not cross a page boundary. > + * The above comment applies as well. > + */ > +ASSERT(__hyp_idmap_text_end - (__hyp_idmap_text_start & PAGE_MASK) <= PAGE_SIZE, > + "HYP init code too big or misaligned") > diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S > index 8b60fde..2c5b76e 100644 > --- a/arch/arm/kernel/vmlinux.lds.S > +++ b/arch/arm/kernel/vmlinux.lds.S > @@ -84,11 +84,7 @@ SECTIONS > *(.discard.*) > } > > -#ifdef CONFIG_XIP_KERNEL > - . = XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR); > -#else > . = PAGE_OFFSET + TEXT_OFFSET; > -#endif > .head.text : { > _text = .; > HEAD_TEXT > @@ -152,14 +148,13 @@ SECTIONS > > _etext = .; /* End of text and rodata section */ > > -#ifndef CONFIG_XIP_KERNEL > -# ifdef CONFIG_ARM_KERNMEM_PERMS > +#ifdef CONFIG_ARM_KERNMEM_PERMS > . = ALIGN(1<<SECTION_SHIFT); > -# else > +#else > . = ALIGN(PAGE_SIZE); > -# endif > - __init_begin = .; > #endif > + __init_begin = .; > + > /* > * The vectors and stubs are relocatable code, and the > * only thing that matters is their relative offsets > @@ -208,29 +203,21 @@ SECTIONS > __pv_table_end = .; > } > .init.data : { > -#ifndef CONFIG_XIP_KERNEL > INIT_DATA > -#endif > INIT_SETUP(16) > INIT_CALLS > CON_INITCALL > SECURITY_INITCALL > INIT_RAM_FS > } > -#ifndef CONFIG_XIP_KERNEL > .exit.data : { > ARM_EXIT_KEEP(EXIT_DATA) > } > -#endif > > #ifdef CONFIG_SMP > PERCPU_SECTION(L1_CACHE_BYTES) > #endif > > -#ifdef CONFIG_XIP_KERNEL > - __data_loc = ALIGN(4); /* location in binary */ > - . = PAGE_OFFSET + TEXT_OFFSET; > -#else > #ifdef CONFIG_ARM_KERNMEM_PERMS > . = ALIGN(1<<SECTION_SHIFT); > #else > @@ -238,7 +225,6 @@ SECTIONS > #endif > __init_end = .; > __data_loc = .; > -#endif > > .data : AT(__data_loc) { > _data = .; /* address in memory */ > @@ -250,15 +236,6 @@ SECTIONS > */ > INIT_TASK_DATA(THREAD_SIZE) > > -#ifdef CONFIG_XIP_KERNEL > - . = ALIGN(PAGE_SIZE); > - __init_begin = .; > - INIT_DATA > - ARM_EXIT_KEEP(EXIT_DATA) > - . = ALIGN(PAGE_SIZE); > - __init_end = .; > -#endif > - > NOSAVE_DATA > CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES) > READ_MOSTLY_DATA(L1_CACHE_BYTES) > -- > 1.7.9.5 > > >
On Thu, 19 Nov 2015, Michal Marek wrote: > Why not have a vmlinux.lds.S and #include a vmlinux-xip.lds.S / > vmlinux-nonxip.lds.S from there? That way, you do not clutter the > main Makefile and you can reuse the boilerplate of the linker script. > > Michal On Thu, 19 Nov 2015, Nicolas Pitre wrote: > I agree with Michal's suggestion to do the selection locally with an > include. That's actually how I started out locally, but I thought if I tried submitting that, I'd get a bunch of "Eww, that's ugly". I'm happy to redo the patch and contain the dysfunctionalism of XIP to the ARM tree. Chris
On 2015-11-19 17:04, Chris Brandt wrote: > On Thu, 19 Nov 2015, Michal Marek wrote: >> Why not have a vmlinux.lds.S and #include a vmlinux-xip.lds.S / >> vmlinux-nonxip.lds.S from there? That way, you do not clutter the >> main Makefile and you can reuse the boilerplate of the linker script. >> >> Michal > > On Thu, 19 Nov 2015, Nicolas Pitre wrote: >> I agree with Michal's suggestion to do the selection locally with an >> include. > > > That's actually how I started out locally, but I thought if I tried submitting that, I'd get a bunch of "Eww, that's ugly". :-). It arguably is not the most beautiful pattern, but it is still easy to understand and there is some prior art in the kernel already, where we include variants of C / asm files from other source files: arch/arm/mm/fault.c:#include "fsr-3level.c" arch/arm/mm/fault.c:#include "fsr-2level.c" arch/m68k/kernel/setup.c:#include "setup_mm.c" arch/m68k/kernel/setup.c:#include "setup_no.c" arch/powerpc/kvm/book3s_segment.S:#include "book3s_64_slb.S" arch/powerpc/kvm/book3s_segment.S:#include "book3s_32_sr.S" mm/percpu.c:#include "percpu-km.c" mm/percpu.c:#include "percpu-vm.c" UM even uses it in its linker script: arch/um/kernel/vmlinux.lds.S:#include "uml.lds.S" arch/um/kernel/vmlinux.lds.S:#include "dyn.lds.S" Michal
On Thu, 19 Nov 2015, Michal Marek wrote: > UM even uses it in its linker script: > > arch/um/kernel/vmlinux.lds.S:#include "uml.lds.S" > arch/um/kernel/vmlinux.lds.S:#include "dyn.lds.S" "When in Rome, ..."
diff --git a/Makefile b/Makefile index 3a0234f..b55440f 100644 --- a/Makefile +++ b/Makefile @@ -900,7 +900,11 @@ virt-y := $(patsubst %/, %/built-in.o, $(virt-y)) # Externally visible symbols (used by link-vmlinux.sh) export KBUILD_VMLINUX_INIT := $(head-y) $(init-y) export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y) $(virt-y) +ifdef CONFIG_XIP_KERNEL +export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux-xip.lds +else export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds +endif export LDFLAGS_vmlinux # used by scripts/pacmage/Makefile export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Documentation include samples scripts tools) diff --git a/arch/arm/kernel/.gitignore b/arch/arm/kernel/.gitignore index c5f676c..522c636 100644 --- a/arch/arm/kernel/.gitignore +++ b/arch/arm/kernel/.gitignore @@ -1 +1,2 @@ vmlinux.lds +vmlinux-xip.lds diff --git a/arch/arm/kernel/vmlinux-xip.lds.S b/arch/arm/kernel/vmlinux-xip.lds.S new file mode 100644 index 0000000..1fd938d --- /dev/null +++ b/arch/arm/kernel/vmlinux-xip.lds.S @@ -0,0 +1,322 @@ +/* ld script to make ARM Linux kernel + * taken from the i386 version by Russell King + * Written by Martin Mares <mj@atrey.karlin.mff.cuni.cz> + */ + +#include <asm-generic/vmlinux.lds.h> +#include <asm/cache.h> +#include <asm/thread_info.h> +#include <asm/memory.h> +#include <asm/page.h> +#ifdef CONFIG_ARM_KERNMEM_PERMS +#include <asm/pgtable.h> +#endif + +#define PROC_INFO \ + . = ALIGN(4); \ + VMLINUX_SYMBOL(__proc_info_begin) = .; \ + *(.proc.info.init) \ + VMLINUX_SYMBOL(__proc_info_end) = .; + +#define IDMAP_TEXT \ + ALIGN_FUNCTION(); \ + VMLINUX_SYMBOL(__idmap_text_start) = .; \ + *(.idmap.text) \ + VMLINUX_SYMBOL(__idmap_text_end) = .; \ + . = ALIGN(PAGE_SIZE); \ + VMLINUX_SYMBOL(__hyp_idmap_text_start) = .; \ + *(.hyp.idmap.text) \ + VMLINUX_SYMBOL(__hyp_idmap_text_end) = .; + +#ifdef CONFIG_HOTPLUG_CPU +#define ARM_CPU_DISCARD(x) +#define ARM_CPU_KEEP(x) x +#else +#define ARM_CPU_DISCARD(x) x +#define ARM_CPU_KEEP(x) +#endif + +#if (defined(CONFIG_SMP_ON_UP) && !defined(CONFIG_DEBUG_SPINLOCK)) || \ + defined(CONFIG_GENERIC_BUG) +#define ARM_EXIT_KEEP(x) x +#define ARM_EXIT_DISCARD(x) +#else +#define ARM_EXIT_KEEP(x) +#define ARM_EXIT_DISCARD(x) x +#endif + +OUTPUT_ARCH(arm) +ENTRY(stext) + +#ifndef __ARMEB__ +jiffies = jiffies_64; +#else +jiffies = jiffies_64 + 4; +#endif + +SECTIONS +{ + /* + * XXX: The linker does not define how output sections are + * assigned to input sections when there are multiple statements + * matching the same input section name. There is no documented + * order of matching. + * + * unwind exit sections must be discarded before the rest of the + * unwind sections get included. + */ + /DISCARD/ : { + *(.ARM.exidx.exit.text) + *(.ARM.extab.exit.text) + ARM_CPU_DISCARD(*(.ARM.exidx.cpuexit.text)) + ARM_CPU_DISCARD(*(.ARM.extab.cpuexit.text)) + ARM_EXIT_DISCARD(EXIT_TEXT) + ARM_EXIT_DISCARD(EXIT_DATA) + EXIT_CALL +#ifndef CONFIG_MMU + *(.text.fixup) + *(__ex_table) +#endif +#ifndef CONFIG_SMP_ON_UP + *(.alt.smp.init) +#endif + *(.discard) + *(.discard.*) + } + + . = XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR); + + .head.text : { + _text = .; + HEAD_TEXT + } + +#ifdef CONFIG_ARM_KERNMEM_PERMS + . = ALIGN(1<<SECTION_SHIFT); +#endif + + .text : { /* Real text segment */ + _stext = .; /* Text and read-only data */ + IDMAP_TEXT + __exception_text_start = .; + *(.exception.text) + __exception_text_end = .; + IRQENTRY_TEXT + TEXT_TEXT + SCHED_TEXT + LOCK_TEXT + KPROBES_TEXT + *(.gnu.warning) + *(.glue_7) + *(.glue_7t) + . = ALIGN(4); + *(.got) /* Global offset table */ + ARM_CPU_KEEP(PROC_INFO) + } + +#ifdef CONFIG_DEBUG_RODATA + . = ALIGN(1<<SECTION_SHIFT); +#endif + RO_DATA(PAGE_SIZE) + + . = ALIGN(4); + __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { + __start___ex_table = .; +#ifdef CONFIG_MMU + *(__ex_table) +#endif + __stop___ex_table = .; + } + +#ifdef CONFIG_ARM_UNWIND + /* + * Stack unwinding tables + */ + . = ALIGN(8); + .ARM.unwind_idx : { + __start_unwind_idx = .; + *(.ARM.exidx*) + __stop_unwind_idx = .; + } + .ARM.unwind_tab : { + __start_unwind_tab = .; + *(.ARM.extab*) + __stop_unwind_tab = .; + } +#endif + + NOTES + + _etext = .; /* End of text and rodata section */ + + /* + * The vectors and stubs are relocatable code, and the + * only thing that matters is their relative offsets + */ + __vectors_start = .; + .vectors 0 : AT(__vectors_start) { + *(.vectors) + } + . = __vectors_start + SIZEOF(.vectors); + __vectors_end = .; + + __stubs_start = .; + .stubs 0x1000 : AT(__stubs_start) { + *(.stubs) + } + . = __stubs_start + SIZEOF(.stubs); + __stubs_end = .; + + INIT_TEXT_SECTION(8) + .exit.text : { + ARM_EXIT_KEEP(EXIT_TEXT) + } + .init.proc.info : { + ARM_CPU_DISCARD(PROC_INFO) + } + .init.arch.info : { + __arch_info_begin = .; + *(.arch.info.init) + __arch_info_end = .; + } + .init.tagtable : { + __tagtable_begin = .; + *(.taglist.init) + __tagtable_end = .; + } +#ifdef CONFIG_SMP_ON_UP + .init.smpalt : { + __smpalt_begin = .; + *(.alt.smp.init) + __smpalt_end = .; + } +#endif + .init.pv_table : { + __pv_table_begin = .; + *(.pv_table) + __pv_table_end = .; + } + .init.data : { + INIT_SETUP(16) + INIT_CALLS + CON_INITCALL + SECURITY_INITCALL + INIT_RAM_FS + } + +#ifdef CONFIG_SMP + PERCPU_SECTION(L1_CACHE_BYTES) +#endif + + __data_loc = ALIGN(4); /* location in binary */ + . = PAGE_OFFSET + TEXT_OFFSET; + + .data : AT(__data_loc) { + _data = .; /* address in memory */ + _sdata = .; + + /* + * first, the init task union, aligned + * to an 8192 byte boundary. + */ + INIT_TASK_DATA(THREAD_SIZE) + + . = ALIGN(PAGE_SIZE); + __init_begin = .; + INIT_DATA + ARM_EXIT_KEEP(EXIT_DATA) + . = ALIGN(PAGE_SIZE); + __init_end = .; + + NOSAVE_DATA + CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES) + READ_MOSTLY_DATA(L1_CACHE_BYTES) + + /* + * and the usual data section + */ + DATA_DATA + CONSTRUCTORS + + _edata = .; + } + _edata_loc = __data_loc + SIZEOF(.data); + +#ifdef CONFIG_HAVE_TCM + /* + * We align everything to a page boundary so we can + * free it after init has commenced and TCM contents have + * been copied to its destination. + */ + .tcm_start : { + . = ALIGN(PAGE_SIZE); + __tcm_start = .; + __itcm_start = .; + } + + /* + * Link these to the ITCM RAM + * Put VMA to the TCM address and LMA to the common RAM + * and we'll upload the contents from RAM to TCM and free + * the used RAM after that. + */ + .text_itcm ITCM_OFFSET : AT(__itcm_start) + { + __sitcm_text = .; + *(.tcm.text) + *(.tcm.rodata) + . = ALIGN(4); + __eitcm_text = .; + } + + /* + * Reset the dot pointer, this is needed to create the + * relative __dtcm_start below (to be used as extern in code). + */ + . = ADDR(.tcm_start) + SIZEOF(.tcm_start) + SIZEOF(.text_itcm); + + .dtcm_start : { + __dtcm_start = .; + } + + /* TODO: add remainder of ITCM as well, that can be used for data! */ + .data_dtcm DTCM_OFFSET : AT(__dtcm_start) + { + . = ALIGN(4); + __sdtcm_data = .; + *(.tcm.data) + . = ALIGN(4); + __edtcm_data = .; + } + + /* Reset the dot pointer or the linker gets confused */ + . = ADDR(.dtcm_start) + SIZEOF(.data_dtcm); + + /* End marker for freeing TCM copy in linked object */ + .tcm_end : AT(ADDR(.dtcm_start) + SIZEOF(.data_dtcm)){ + . = ALIGN(PAGE_SIZE); + __tcm_end = .; + } +#endif + + BSS_SECTION(0, 0, 0) + _end = .; + + STABS_DEBUG +} + +/* + * These must never be empty + * If you have to comment these two assert statements out, your + * binutils is too old (for other reasons as well) + */ +ASSERT((__proc_info_end - __proc_info_begin), "missing CPU support") +ASSERT((__arch_info_end - __arch_info_begin), "no machine record defined") + +/* + * The HYP init code can't be more than a page long, + * and should not cross a page boundary. + * The above comment applies as well. + */ +ASSERT(__hyp_idmap_text_end - (__hyp_idmap_text_start & PAGE_MASK) <= PAGE_SIZE, + "HYP init code too big or misaligned") diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index 8b60fde..2c5b76e 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -84,11 +84,7 @@ SECTIONS *(.discard.*) } -#ifdef CONFIG_XIP_KERNEL - . = XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR); -#else . = PAGE_OFFSET + TEXT_OFFSET; -#endif .head.text : { _text = .; HEAD_TEXT @@ -152,14 +148,13 @@ SECTIONS _etext = .; /* End of text and rodata section */ -#ifndef CONFIG_XIP_KERNEL -# ifdef CONFIG_ARM_KERNMEM_PERMS +#ifdef CONFIG_ARM_KERNMEM_PERMS . = ALIGN(1<<SECTION_SHIFT); -# else +#else . = ALIGN(PAGE_SIZE); -# endif - __init_begin = .; #endif + __init_begin = .; + /* * The vectors and stubs are relocatable code, and the * only thing that matters is their relative offsets @@ -208,29 +203,21 @@ SECTIONS __pv_table_end = .; } .init.data : { -#ifndef CONFIG_XIP_KERNEL INIT_DATA -#endif INIT_SETUP(16) INIT_CALLS CON_INITCALL SECURITY_INITCALL INIT_RAM_FS } -#ifndef CONFIG_XIP_KERNEL .exit.data : { ARM_EXIT_KEEP(EXIT_DATA) } -#endif #ifdef CONFIG_SMP PERCPU_SECTION(L1_CACHE_BYTES) #endif -#ifdef CONFIG_XIP_KERNEL - __data_loc = ALIGN(4); /* location in binary */ - . = PAGE_OFFSET + TEXT_OFFSET; -#else #ifdef CONFIG_ARM_KERNMEM_PERMS . = ALIGN(1<<SECTION_SHIFT); #else @@ -238,7 +225,6 @@ SECTIONS #endif __init_end = .; __data_loc = .; -#endif .data : AT(__data_loc) { _data = .; /* address in memory */ @@ -250,15 +236,6 @@ SECTIONS */ INIT_TASK_DATA(THREAD_SIZE) -#ifdef CONFIG_XIP_KERNEL - . = ALIGN(PAGE_SIZE); - __init_begin = .; - INIT_DATA - ARM_EXIT_KEEP(EXIT_DATA) - . = ALIGN(PAGE_SIZE); - __init_end = .; -#endif - NOSAVE_DATA CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES) READ_MOSTLY_DATA(L1_CACHE_BYTES)
When building an XIP kernel, the linker script needs to be much different than a conventional kernel's script. Over time, it's been difficult to maintain both XIP and non-XIP layouts in one linker script. Therefore, this patch separates the two procedures into two completely different files. The new linker script is essentially a straight copy of the current script with all the non-CONFIG_XIP_KERNEL portions removed. Additionally, all CONFIG_XIP_KERNEL portions have been removed from the existing linker script...never to return again. From now on, for any architecture, when CONFIG_XIP_KERNEL is enabled, you must provide a vmlinux-xip.lds.S for the build process. Signed-off-by: Chris Brandt <chris.brandt@renesas.com> --- Makefile | 4 + arch/arm/kernel/.gitignore | 1 + arch/arm/kernel/vmlinux-xip.lds.S | 322 +++++++++++++++++++++++++++++++++++++ arch/arm/kernel/vmlinux.lds.S | 31 +--- 4 files changed, 331 insertions(+), 27 deletions(-) create mode 100644 arch/arm/kernel/vmlinux-xip.lds.S