xtensa: reorganize vectors placement

Allow vectors to be either merged into the kernel .text or put at a
fixed virtual address independently of XIP option. Drop option that
puts vectors at a fixed offset from the kernel text. Add choice to
Kconfig.
Vectors at fixed virtual address may be useful for XIP-aware MTD support
and for noMMU configurations with available IRAM. Configurations without
VECBASE register must put their vectors at specific locations regardless
of the selected option. All other configurations should happily use
merged vectors.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
Max Filippov 2020-01-31 20:11:24 -08:00
parent 4f17664a44
commit 5e4417f921
6 changed files with 51 additions and 20 deletions

View File

@ -572,15 +572,41 @@ config KERNEL_LOAD_ADDRESS
If unsure, leave the default value here.
config VECTORS_OFFSET
hex "Kernel vectors offset"
default 0x00003000
depends on !XIP_KERNEL
choice
prompt "Relocatable vectors location"
default XTENSA_VECTORS_IN_TEXT
help
This is the offset of the kernel image from the relocatable vectors
base.
Choose whether relocatable vectors are merged into the kernel .text
or placed separately at runtime. This option does not affect
configurations without VECBASE register where vectors are always
placed at their hardware-defined locations.
If unsure, leave the default value here.
config XTENSA_VECTORS_IN_TEXT
bool "Merge relocatable vectors into kernel text"
depends on !MTD_XIP
help
This option puts relocatable vectors into the kernel .text section
with proper alignment.
This is a safe choice for most configurations.
config XTENSA_VECTORS_SEPARATE
bool "Put relocatable vectors at fixed address"
help
This option puts relocatable vectors at specific virtual address.
Vectors are merged with the .init data in the kernel image and
are copied into their designated location during kernel startup.
Use it to put vectors into IRAM or out of FLASH on kernels with
XIP-aware MTD support.
endchoice
config VECTORS_ADDR
hex "Kernel vectors virtual address"
default 0x00000000
depends on XTENSA_VECTORS_SEPARATE
help
This is the virtual address of the (relocatable) vectors base.
It must be within KSEG if MMU is used.
config XIP_DATA_ADDR
hex "XIP kernel data virtual address"

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@ -30,7 +30,6 @@ CONFIG_SMP=y
CONFIG_HOTPLUG_CPU=y
# CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX is not set
# CONFIG_PCI is not set
CONFIG_VECTORS_OFFSET=0x00002000
CONFIG_XTENSA_PLATFORM_XTFPGA=y
CONFIG_CMDLINE_BOOL=y
CONFIG_CMDLINE="earlycon=uart8250,mmio32native,0xfd050020,115200n8 console=ttyS0,115200n8 ip=dhcp root=/dev/nfs rw debug memmap=96M@0"

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@ -19,7 +19,6 @@ CONFIG_KALLSYMS_ALL=y
CONFIG_PERF_EVENTS=y
CONFIG_XTENSA_VARIANT_DC233C=y
CONFIG_XTENSA_UNALIGNED_USER=y
CONFIG_VECTORS_OFFSET=0x00002000
CONFIG_XTENSA_KSEG_512M=y
CONFIG_HIGHMEM=y
CONFIG_CMDLINE_BOOL=y

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@ -34,8 +34,8 @@
#endif
#define RESET_VECTOR1_VADDR (XCHAL_RESET_VECTOR1_VADDR)
#ifdef CONFIG_VECTORS_OFFSET
#define VECBASE_VADDR (KERNELOFFSET - CONFIG_VECTORS_OFFSET)
#ifdef CONFIG_VECTORS_ADDR
#define VECBASE_VADDR (CONFIG_VECTORS_ADDR)
#else
#define VECBASE_VADDR _vecbase
#endif

View File

@ -349,7 +349,7 @@ void __init setup_arch(char **cmdline_p)
mem_reserve(__pa(_xip_start), __pa(_xip_end));
#endif
#ifdef CONFIG_VECTORS_OFFSET
#ifdef CONFIG_VECTORS_ADDR
mem_reserve(__pa(&_WindowVectors_text_start),
__pa(&_WindowVectors_text_end));
@ -388,7 +388,7 @@ void __init setup_arch(char **cmdline_p)
__pa(&_Level6InterruptVector_text_end));
#endif
#endif /* CONFIG_VECTORS_OFFSET */
#endif /* CONFIG_VECTORS_ADDR */
#ifdef CONFIG_SMP
mem_reserve(__pa(&_SecondaryResetVector_text_start),

View File

@ -47,9 +47,15 @@ jiffies = jiffies_64;
LONG(sym ## _end); \
LONG(LOADADDR(section))
#if !defined(CONFIG_VECTORS_ADDR) && XCHAL_HAVE_VECBASE
#define MERGED_VECTORS 1
#else
#define MERGED_VECTORS 0
#endif
/*
* Macro to define a section for a vector. When CONFIG_VECTORS_OFFSET is
* defined code for every vector is located with other init data. At startup
* Macro to define a section for a vector. When MERGED_VECTORS is 0
* code for every vector is located with other init data. At startup
* time head.S copies code for every vector to its final position according
* to description recorded in the corresponding RELOCATE_ENTRY.
*/
@ -84,7 +90,7 @@ SECTIONS
/* The HEAD_TEXT section must be the first section! */
HEAD_TEXT
#ifndef CONFIG_VECTORS_OFFSET
#if MERGED_VECTORS
. = ALIGN(PAGE_SIZE);
_vecbase = .;
@ -159,7 +165,7 @@ SECTIONS
. = ALIGN(16);
__boot_reloc_table_start = ABSOLUTE(.);
#ifdef CONFIG_VECTORS_OFFSET
#if !MERGED_VECTORS
RELOCATE_ENTRY(_WindowVectors_text,
.WindowVectors.text);
#if XCHAL_EXCM_LEVEL >= 2
@ -220,7 +226,7 @@ SECTIONS
#undef LAST
#define LAST .dummy
#ifdef CONFIG_VECTORS_OFFSET
#if !MERGED_VECTORS
/* The vectors are relocated to the real position at startup time */
SECTION_VECTOR4 (_WindowVectors_text,
@ -299,7 +305,7 @@ SECTIONS
#define LAST .SecondaryResetVector.text
#endif
#ifdef CONFIG_VECTORS_OFFSET
#if !MERGED_VECTORS
SECTION_VECTOR4 (_exception_text,
.exception.text,
,
@ -310,6 +316,7 @@ SECTIONS
#endif
. = (LOADADDR(LAST) + SIZEOF(LAST) + 3) & ~ 3;
.dummy1 : AT(ADDR(.dummy1)) { LONG(0) }
. = ALIGN(PAGE_SIZE);
#ifndef CONFIG_XIP_KERNEL
@ -327,7 +334,7 @@ SECTIONS
#undef LOAD_OFFSET
#define LOAD_OFFSET \
(CONFIG_XIP_DATA_ADDR - (LOADADDR(.dummy) + SIZEOF(.dummy) + 3) & ~ 3)
(CONFIG_XIP_DATA_ADDR - (LOADADDR(.dummy1) + SIZEOF(.dummy1) + 3) & ~ 3)
_xip_data_start = .;
_sdata = .;