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firmware: remove copy-base relocation

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Remove copy-base relocations that are no longer needed.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Samuel Holland <samuel.holland@sifive.com>
Tested-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
This commit is contained in:
Xiang W
2024-03-12 16:24:59 +08:00
committed by Anup Patel
parent 5186da687d
commit 76d7e9b8ee
5 changed files with 11 additions and 115 deletions
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8
Makefile
View File

@@ -179,6 +179,10 @@ CC_SUPPORT_STRICT_ALIGN := $(shell $(CC) $(CLANG_TARGET) $(RELAX_FLAG) -nostdlib
# Check whether the assembler and the compiler support the Zicsr and Zifencei extensions
CC_SUPPORT_ZICSR_ZIFENCEI := $(shell $(CC) $(CLANG_TARGET) $(RELAX_FLAG) -nostdlib -march=rv$(OPENSBI_CC_XLEN)imafd_zicsr_zifencei -x c /dev/null -o /dev/null 2>&1 | grep "zicsr\|zifencei" > /dev/null && echo n || echo y)
ifneq ($(OPENSBI_LD_PIE),y)
$(error Your linker does not support creating PIEs, opensbi requires this.)
endif
# Build Info:
# OPENSBI_BUILD_TIME_STAMP -- the compilation time stamp
# OPENSBI_BUILD_COMPILER_VERSION -- the compiler version info
@@ -356,7 +360,7 @@ CFLAGS += -mcmodel=$(PLATFORM_RISCV_CODE_MODEL)
CFLAGS += $(RELAX_FLAG)
CFLAGS += $(GENFLAGS)
CFLAGS += $(platform-cflags-y)
CFLAGS += -fno-pie -no-pie
CFLAGS += -fPIE -pie
CFLAGS += $(firmware-cflags-y)
CPPFLAGS += $(GENFLAGS)
@@ -365,6 +369,7 @@ CPPFLAGS += $(firmware-cppflags-y)
ASFLAGS = -g -Wall -nostdlib
ASFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
ASFLAGS += -fPIE
# Optionally supported flags
ifeq ($(CC_SUPPORT_SAVE_RESTORE),y)
ASFLAGS += -mno-save-restore
@@ -391,6 +396,7 @@ ifeq ($(OPENSBI_LD_EXCLUDE_LIBS),y)
ELFFLAGS += -Wl,--exclude-libs,ALL
endif
ELFFLAGS += -Wl,--build-id=none
ELFFLAGS += -Wl,--no-dynamic-linker -Wl,-pie
ELFFLAGS += $(platform-ldflags-y)
ELFFLAGS += $(firmware-ldflags-y)

3
README.md
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@@ -276,8 +276,7 @@ document.
NOTE: Using Clang with a `riscv*-linux-gnu` GNU binutils linker has been seen
to produce broken binaries with missing relocations; it is therefore currently
recommended that this combination be avoided or *FW_PIC=n* be used to disable
building OpenSBI as a position-independent binary.
recommended that this combination be avoided.
Building with timestamp and compiler info
-----------------------------------------

6
docs/firmware/fw.md
View File

@@ -69,12 +69,6 @@ parameters:
argument by the prior booting stage.
* **FW_FDT_PADDING** - Optional zero bytes padding to the embedded flattened
device tree binary file specified by **FW_FDT_PATH** option.
* **FW_PIC** - "FW_PIC=y" generates position independent executable firmware
images. OpenSBI can run at arbitrary address with appropriate alignment.
Therefore, the original relocation mechanism ("FW_PIC=n") will be skipped.
In other words, OpenSBI will directly run at the load address without any
code movement. This option requires a toolchain with PIE support, and it
is on by default.
Additionally, each firmware type as a set of type specific configuration
parameters. Detailed information for each firmware type can be found in the

98
firmware/fw_base.S
View File

@@ -15,8 +15,7 @@
#include <sbi/sbi_trap.h>
#define BOOT_STATUS_LOTTERY_DONE 1
#define BOOT_STATUS_RELOCATE_DONE 2
#define BOOT_STATUS_BOOT_HART_DONE 3
#define BOOT_STATUS_BOOT_HART_DONE 2
.macro MOV_3R __d0, __s0, __d1, __s1, __d2, __s2
add \__d0, \__s0, zero
@@ -32,17 +31,6 @@
add \__d4, \__s4, zero
.endm
/*
* If __start_reg <= __check_reg and __check_reg < __end_reg then
* jump to __pass
*/
.macro BRANGE __start_reg, __end_reg, __check_reg, __jump_lable
blt \__check_reg, \__start_reg, 999f
bge \__check_reg, \__end_reg, 999f
j \__jump_lable
999:
.endm
.section .entry, "ax", %progbits
.align 3
.globl _start
@@ -56,15 +44,14 @@ _start:
li a7, -1
beq a6, a7, _try_lottery
/* Jump to relocation wait loop if we are not boot hart */
bne a0, a6, _wait_relocate_copy_done
bne a0, a6, _wait_for_boot_hart
_try_lottery:
/* Jump to relocation wait loop if we don't get relocation lottery */
lla a6, _boot_status
li a7, BOOT_STATUS_LOTTERY_DONE
amoswap.w a6, a7, (a6)
bnez a6, _wait_relocate_copy_done
bnez a6, _wait_for_boot_hart
#ifdef FW_PIC
/* relocate the global table content */
li t0, FW_TEXT_START /* link start */
lla t1, _fw_start /* load start */
@@ -85,86 +72,7 @@ _try_lottery:
3:
addi t0, t0, (REGBYTES * 3)
blt t0, t1, 2b
j _relocate_done
_wait_relocate_copy_done:
j _wait_for_boot_hart
#else
/* Relocate if load address != link address */
_relocate:
li t0, FW_TEXT_START /* link start */
lla t2, _fw_start /* load start */
lla t3, _fw_reloc_end /* load end */
sub t6, t2, t0 /* load offset */
sub t1, t3, t6 /* link end */
beq t0, t2, _relocate_done
lla t4, _relocate_done
sub t4, t4, t6
blt t2, t0, _relocate_copy_to_upper
_relocate_copy_to_lower:
ble t1, t2, _relocate_copy_to_lower_loop
lla t3, _boot_status
BRANGE t2, t1, t3, _start_hang
lla t3, _relocate
lla t5, _relocate_done
BRANGE t2, t1, t3, _start_hang
BRANGE t2, t1, t5, _start_hang
BRANGE t3, t5, t2, _start_hang
_relocate_copy_to_lower_loop:
REG_L t3, 0(t2)
REG_S t3, 0(t0)
add t0, t0, __SIZEOF_POINTER__
add t2, t2, __SIZEOF_POINTER__
blt t0, t1, _relocate_copy_to_lower_loop
jr t4
_relocate_copy_to_upper:
ble t3, t0, _relocate_copy_to_upper_loop
lla t2, _boot_status
BRANGE t0, t3, t2, _start_hang
lla t2, _relocate
lla t5, _relocate_done
BRANGE t0, t3, t2, _start_hang
BRANGE t0, t3, t5, _start_hang
BRANGE t2, t5, t0, _start_hang
_relocate_copy_to_upper_loop:
add t3, t3, -__SIZEOF_POINTER__
add t1, t1, -__SIZEOF_POINTER__
REG_L t2, 0(t3)
REG_S t2, 0(t1)
blt t0, t1, _relocate_copy_to_upper_loop
jr t4
_wait_relocate_copy_done:
lla t0, _fw_start
li t1, FW_TEXT_START
beq t0, t1, _wait_for_boot_hart
lla t2, _boot_status
lla t3, _wait_for_boot_hart
sub t3, t3, t0
add t3, t3, t1
1:
/* waitting for relocate copy done (_boot_status == 1) */
li t4, BOOT_STATUS_RELOCATE_DONE
REG_L t5, 0(t2)
/* Reduce the bus traffic so that boot hart may proceed faster */
nop
nop
nop
bgt t4, t5, 1b
jr t3
#endif
_relocate_done:
/*
* Mark relocate copy done
* Use _boot_status copy relative to the load address
*/
lla t0, _boot_status
#ifndef FW_PIC
add t0, t0, t6
#endif
li t1, BOOT_STATUS_RELOCATE_DONE
REG_S t1, 0(t0)
fence rw, rw
/* At this point we are running from link address */
/* Reset all registers except ra, a0, a1, a2, a3 and a4 for boot HART */

11
firmware/objects.mk
View File

@@ -13,17 +13,6 @@ firmware-cflags-y +=
firmware-asflags-y +=
firmware-ldflags-y +=
ifndef FW_PIC
FW_PIC := $(OPENSBI_LD_PIE)
endif
ifeq ($(FW_PIC),y)
firmware-genflags-y += -DFW_PIC
firmware-asflags-y += -fpic
firmware-cflags-y += -fPIE -pie
firmware-ldflags-y += -Wl,--no-dynamic-linker -Wl,-pie
endif
ifdef FW_TEXT_START
firmware-genflags-y += -DFW_TEXT_START=$(FW_TEXT_START)
endif