Commit f8f02ca7 authored by Max Filippov's avatar Max Filippov
Browse files

xtensa: build kernel with text-section-literals 



vmlinux.lds.S doesn't do anything special with literals, so instead of
keeping them separate put them into the corresponding text sections.
Drop explicit .literal sections from the vmlinux.lds.S, use standard
section macros. Mark literal pool locations in the assembly sources.
Unfortunately assembler doesn't put literals into .init sections and
external libgcc may still have .literal sections, so sed transformation
to the linker script is still needed.

Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
parent 7bf5234d

arch/xtensa/Makefile

+3 −3
Original line number Diff line number Diff line
@@ -42,12 +42,12 @@ export PLATFORM 


# temporarily until string.h is fixed

KBUILD_CFLAGS += -ffreestanding -D__linux__



KBUILD_CFLAGS += -pipe -mlongcalls



KBUILD_CFLAGS += -pipe -mlongcalls -mtext-section-literals

KBUILD_CFLAGS += $(call cc-option,-mforce-no-pic,)

KBUILD_CFLAGS += $(call cc-option,-mno-serialize-volatile,)



KBUILD_AFLAGS += -mlongcalls -mtext-section-literals



ifneq ($(CONFIG_LD_NO_RELAX),)

LDFLAGS := --no-relax

endif

arch/xtensa/boot/boot-redboot/bootstrap.S

+1 −0
Original line number Diff line number Diff line
@@ -42,6 +42,7 @@ __start_a0: 
	.align 4



	.section .text, "ax"

	.literal_position

	.begin literal_prefix .text



	/* put literals in here! */

arch/xtensa/kernel/Makefile

+0 −3
Original line number Diff line number Diff line
@@ -17,9 +17,6 @@ obj-$(CONFIG_XTENSA_VARIANT_HAVE_PERF_EVENTS) += perf_event.o 
obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o

obj-$(CONFIG_S32C1I_SELFTEST) += s32c1i_selftest.o



AFLAGS_head.o += -mtext-section-literals

AFLAGS_mxhead.o += -mtext-section-literals



# In the Xtensa architecture, assembly generates literals which must always

# precede the L32R instruction with a relative offset less than 256 kB.

# Therefore, the .text and .literal section must be combined in parenthesis

arch/xtensa/kernel/align.S

+1 −1
Original line number Diff line number Diff line
@@ -155,7 +155,7 @@ 
 *	     <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception

 */





	.literal_position

ENTRY(fast_unaligned)



	/* Note: We don't expect the address to be aligned on a word

arch/xtensa/kernel/entry.S

+8 −0
Original line number Diff line number Diff line
@@ -125,6 +125,7 @@ 
 *

 * Note: _user_exception might be at an odd address. Don't use call0..call12

 */

	.literal_position



ENTRY(user_exception)
@@ -777,6 +778,8 @@ ENDPROC(kernel_exception) 
 * When we get here,  a0 is trashed and saved to excsave[debuglevel]

 */



	.literal_position



ENTRY(debug_exception)



	rsr	a0, SREG_EPS + XCHAL_DEBUGLEVEL
@@ -916,6 +919,8 @@ ENDPROC(debug_exception) 
unrecoverable_text:

	.ascii "Unrecoverable error in exception handler\0"



	.literal_position



ENTRY(unrecoverable_exception)



	movi	a0, 1
@@ -1117,6 +1122,8 @@ ENDPROC(fast_syscall_unrecoverable) 
 *		j done

 */



	.literal_position



#ifdef CONFIG_FAST_SYSCALL_XTENSA



#define TRY								\
@@ -1887,6 +1894,7 @@ ENDPROC(fast_store_prohibited) 
 * void system_call (struct pt_regs* regs, int exccause)

 *                            a2                 a3

 */

	.literal_position



ENTRY(system_call)

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