diff options
| -rw-r--r-- | arch/loongarch/Makefile | 18 | ||||
| -rw-r--r-- | arch/loongarch/include/asm/percpu.h | 9 | ||||
| -rw-r--r-- | arch/loongarch/kernel/head.S | 12 | ||||
| -rw-r--r-- | arch/loongarch/kernel/vmlinux.lds.S | 4 |
4 files changed, 37 insertions, 6 deletions
diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile index 84689c3ee3af..42352f905858 100644 --- a/arch/loongarch/Makefile +++ b/arch/loongarch/Makefile @@ -43,10 +43,28 @@ endif cflags-y += -G0 -pipe -msoft-float LDFLAGS_vmlinux += -G0 -static -n -nostdlib + +# When the assembler supports explicit relocation hint, we must use it. +# GCC may have -mexplicit-relocs off by default if it was built with an old +# assembler, so we force it via an option. +# +# When the assembler does not supports explicit relocation hint, we can't use +# it. Disable it if the compiler supports it. +# +# If you've seen "unknown reloc hint" message building the kernel and you are +# now wondering why "-mexplicit-relocs" is not wrapped with cc-option: the +# combination of a "new" assembler and "old" compiler is not supported. Either +# upgrade the compiler or downgrade the assembler. +ifdef CONFIG_AS_HAS_EXPLICIT_RELOCS +cflags-y += -mexplicit-relocs +KBUILD_CFLAGS_KERNEL += -mdirect-extern-access +else +cflags-y += $(call cc-option,-mno-explicit-relocs) KBUILD_AFLAGS_KERNEL += -Wa,-mla-global-with-pcrel KBUILD_CFLAGS_KERNEL += -Wa,-mla-global-with-pcrel KBUILD_AFLAGS_MODULE += -Wa,-mla-global-with-abs KBUILD_CFLAGS_MODULE += -fplt -Wa,-mla-global-with-abs,-mla-local-with-abs +endif cflags-y += -ffreestanding cflags-y += $(call cc-option, -mno-check-zero-division) diff --git a/arch/loongarch/include/asm/percpu.h b/arch/loongarch/include/asm/percpu.h index 0bd6b0110198..ad8d88494554 100644 --- a/arch/loongarch/include/asm/percpu.h +++ b/arch/loongarch/include/asm/percpu.h @@ -8,6 +8,15 @@ #include <asm/cmpxchg.h> #include <asm/loongarch.h> +/* + * The "address" (in fact, offset from $r21) of a per-CPU variable is close to + * the loading address of main kernel image, but far from where the modules are + * loaded. Tell the compiler this fact when using explicit relocs. + */ +#if defined(MODULE) && defined(CONFIG_AS_HAS_EXPLICIT_RELOCS) +#define PER_CPU_ATTRIBUTES __attribute__((model("extreme"))) +#endif + /* Use r21 for fast access */ register unsigned long __my_cpu_offset __asm__("$r21"); diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S index 7e57ae8741b1..0c67c24ce087 100644 --- a/arch/loongarch/kernel/head.S +++ b/arch/loongarch/kernel/head.S @@ -57,19 +57,19 @@ SYM_CODE_START(kernel_entry) # kernel entry point li.w t0, 0x00 # FPE=0, SXE=0, ASXE=0, BTE=0 csrwr t0, LOONGARCH_CSR_EUEN - la t0, __bss_start # clear .bss + la.pcrel t0, __bss_start # clear .bss st.d zero, t0, 0 - la t1, __bss_stop - LONGSIZE + la.pcrel t1, __bss_stop - LONGSIZE 1: addi.d t0, t0, LONGSIZE st.d zero, t0, 0 bne t0, t1, 1b - la t0, fw_arg0 + la.pcrel t0, fw_arg0 st.d a0, t0, 0 # firmware arguments - la t0, fw_arg1 + la.pcrel t0, fw_arg1 st.d a1, t0, 0 - la t0, fw_arg2 + la.pcrel t0, fw_arg2 st.d a2, t0, 0 /* KSave3 used for percpu base, initialized as 0 */ @@ -77,7 +77,7 @@ SYM_CODE_START(kernel_entry) # kernel entry point /* GPR21 used for percpu base (runtime), initialized as 0 */ move u0, zero - la tp, init_thread_union + la.pcrel tp, init_thread_union /* Set the SP after an empty pt_regs. */ PTR_LI sp, (_THREAD_SIZE - 32 - PT_SIZE) PTR_ADD sp, sp, tp diff --git a/arch/loongarch/kernel/vmlinux.lds.S b/arch/loongarch/kernel/vmlinux.lds.S index e5890bec2bf6..b3309a5e695b 100644 --- a/arch/loongarch/kernel/vmlinux.lds.S +++ b/arch/loongarch/kernel/vmlinux.lds.S @@ -55,6 +55,10 @@ SECTIONS EXCEPTION_TABLE(16) + .got : ALIGN(16) { *(.got) } + .plt : ALIGN(16) { *(.plt) } + .got.plt : ALIGN(16) { *(.got.plt) } + . = ALIGN(PECOFF_SEGMENT_ALIGN); __init_begin = .; __inittext_begin = .; |