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: Max Filippov <jcmvbkbc@gmail.com>

diff --git a/arch/xtensa/Makefile b/arch/xtensa/Makefile
index a206598b5d95c3302b053a38920c6249dec23ed5..3a934b72a2728948a0009ca3a92faf63c0b4a1ed 100644 (file)
--- a/arch/xtensa/Makefile
+++ b/arch/xtensa/Makefile
@@ -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

diff --git a/arch/xtensa/boot/boot-redboot/bootstrap.S b/arch/xtensa/boot/boot-redboot/bootstrap.S
index bf7fabe6310dbf38d4dd9dfc0a9d4a572a430441..bbf3b4b080cdaf8eceee319382b58666fe1e8601 100644 (file)
--- a/arch/xtensa/boot/boot-redboot/bootstrap.S
+++ b/arch/xtensa/boot/boot-redboot/bootstrap.S
@@ -42,6 +42,7 @@ __start_a0:
        .align 4
 
        .section .text, "ax"
+       .literal_position
        .begin literal_prefix .text
 
        /* put literals in here! */

diff --git a/arch/xtensa/kernel/Makefile b/arch/xtensa/kernel/Makefile
index bb8d55775a97ce99637eee4baacb44068c173282..91907590d183fd8385d5182c53df18c1cfec4cd0 100644 (file)
--- a/arch/xtensa/kernel/Makefile
+++ b/arch/xtensa/kernel/Makefile
@@ -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

diff --git a/arch/xtensa/kernel/align.S b/arch/xtensa/kernel/align.S
index 890004af03a927fb8768a4d3e7878ccd3c6a1ddf..24b3189d7841a68b1e67d36b36d383d41196620d 100644 (file)
--- a/arch/xtensa/kernel/align.S
+++ b/arch/xtensa/kernel/align.S
@@ -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

diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 37a239556889c0cc3912d921585879c4abd98876..5d5707831626542cbc062dc3597d16944a1bd57d 100644 (file)
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -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)
 

diff --git a/arch/xtensa/kernel/setup.c b/arch/xtensa/kernel/setup.c
index 08175df7a69eecfcb7ad6a6fa68ce226a16b8d0a..253a0178f1bdd85435dc5547c7ed0fdc58e0b046 100644 (file)
--- a/arch/xtensa/kernel/setup.c
+++ b/arch/xtensa/kernel/setup.c
@@ -277,13 +277,13 @@ extern char _end[];
 extern char _stext[];
 extern char _WindowVectors_text_start;
 extern char _WindowVectors_text_end;
-extern char _DebugInterruptVector_literal_start;
+extern char _DebugInterruptVector_text_start;
 extern char _DebugInterruptVector_text_end;
-extern char _KernelExceptionVector_literal_start;
+extern char _KernelExceptionVector_text_start;
 extern char _KernelExceptionVector_text_end;
-extern char _UserExceptionVector_literal_start;
+extern char _UserExceptionVector_text_start;
 extern char _UserExceptionVector_text_end;
-extern char _DoubleExceptionVector_literal_start;
+extern char _DoubleExceptionVector_text_start;
 extern char _DoubleExceptionVector_text_end;
 #if XCHAL_EXCM_LEVEL >= 2
 extern char _Level2InterruptVector_text_start;
@@ -339,16 +339,16 @@ void __init setup_arch(char **cmdline_p)
        mem_reserve(__pa(&_WindowVectors_text_start),
                    __pa(&_WindowVectors_text_end));
 
-       mem_reserve(__pa(&_DebugInterruptVector_literal_start),
+       mem_reserve(__pa(&_DebugInterruptVector_text_start),
                    __pa(&_DebugInterruptVector_text_end));
 
-       mem_reserve(__pa(&_KernelExceptionVector_literal_start),
+       mem_reserve(__pa(&_KernelExceptionVector_text_start),
                    __pa(&_KernelExceptionVector_text_end));
 
-       mem_reserve(__pa(&_UserExceptionVector_literal_start),
+       mem_reserve(__pa(&_UserExceptionVector_text_start),
                    __pa(&_UserExceptionVector_text_end));
 
-       mem_reserve(__pa(&_DoubleExceptionVector_literal_start),
+       mem_reserve(__pa(&_DoubleExceptionVector_text_start),
                    __pa(&_DoubleExceptionVector_text_end));
 
 #if XCHAL_EXCM_LEVEL >= 2

diff --git a/arch/xtensa/kernel/vectors.S b/arch/xtensa/kernel/vectors.S
index 332e9d635fb6f07a21855f215ab55435ae24e6c5..2bc85051c680fbf1e5f3af9a421649e288cb0145 100644 (file)
--- a/arch/xtensa/kernel/vectors.S
+++ b/arch/xtensa/kernel/vectors.S
@@ -205,9 +205,6 @@ ENDPROC(_KernelExceptionVector)
  */
 
        .section .DoubleExceptionVector.text, "ax"
-       .begin literal_prefix .DoubleExceptionVector
-       .globl _DoubleExceptionVector_WindowUnderflow
-       .globl _DoubleExceptionVector_WindowOverflow
 
 ENTRY(_DoubleExceptionVector)
 
@@ -217,8 +214,12 @@ ENTRY(_DoubleExceptionVector)
        /* Check for kernel double exception (usually fatal). */
 
        rsr     a2, ps
-       _bbci.l a2, PS_UM_BIT, .Lksp
+       _bbsi.l a2, PS_UM_BIT, 1f
+       j       .Lksp
 
+       .align  4
+       .literal_position
+1:
        /* Check if we are currently handling a window exception. */
        /* Note: We don't need to indicate that we enter a critical section. */
 
@@ -475,11 +476,8 @@ _DoubleExceptionVector_handle_exception:
        rotw    -3
        j       1b
 
-
 ENDPROC(_DoubleExceptionVector)
 
-       .end literal_prefix
-
        .text
 /*
  * Fixup handler for TLB miss in double exception handler for window owerflow.
@@ -508,6 +506,8 @@ ENDPROC(_DoubleExceptionVector)
  * a3: exctable, original value in excsave1
  */
 
+       .literal_position
+
 ENTRY(window_overflow_restore_a0_fixup)
 
        rsr     a0, ps

diff --git a/arch/xtensa/kernel/vmlinux.lds.S b/arch/xtensa/kernel/vmlinux.lds.S
index 162c77e53ca845bf26ba9ab40ce4cd606f5a7060..70b731edc7b85259ab3a7af36831306fb99dc82f 100644 (file)
--- a/arch/xtensa/kernel/vmlinux.lds.S
+++ b/arch/xtensa/kernel/vmlinux.lds.S
@@ -45,24 +45,16 @@ jiffies = jiffies_64;
        LONG(sym ## _end);                      \
        LONG(LOADADDR(section))
 
-/* Macro to define a section for a vector.
- *
- * Use of the MIN function catches the types of errors illustrated in
- * the following example:
- *
- * Assume the section .DoubleExceptionVector.literal is completely
- * full.  Then a programmer adds code to .DoubleExceptionVector.text
- * that produces another literal.  The final literal position will
- * overlay onto the first word of the adjacent code section
- * .DoubleExceptionVector.text.  (In practice, the literals will
- * overwrite the code, and the first few instructions will be
- * garbage.)
+/*
+ * 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
+ * time head.S copies code for every vector to its final position according
+ * to description recorded in the corresponding RELOCATE_ENTRY.
  */
 
 #ifdef CONFIG_VECTORS_OFFSET
-#define SECTION_VECTOR(sym, section, addr, max_prevsec_size, prevsec)       \
-  section addr : AT((MIN(LOADADDR(prevsec) + max_prevsec_size,             \
-                        LOADADDR(prevsec) + SIZEOF(prevsec)) + 3) & ~ 3)   \
+#define SECTION_VECTOR(sym, section, addr, prevsec)                         \
+  section addr : AT(((LOADADDR(prevsec) + SIZEOF(prevsec)) + 3) & ~ 3)      \
   {                                                                        \
     . = ALIGN(4);                                                          \
     sym ## _start = ABSOLUTE(.);                                           \
@@ -112,26 +104,19 @@ SECTIONS
 #if XCHAL_EXCM_LEVEL >= 6
   SECTION_VECTOR (.Level6InterruptVector.text, INTLEVEL6_VECTOR_VADDR)
 #endif
-  SECTION_VECTOR (.DebugInterruptVector.literal, DEBUG_VECTOR_VADDR - 4)
   SECTION_VECTOR (.DebugInterruptVector.text, DEBUG_VECTOR_VADDR)
-  SECTION_VECTOR (.KernelExceptionVector.literal, KERNEL_VECTOR_VADDR - 4)
   SECTION_VECTOR (.KernelExceptionVector.text, KERNEL_VECTOR_VADDR)
-  SECTION_VECTOR (.UserExceptionVector.literal, USER_VECTOR_VADDR - 4)
   SECTION_VECTOR (.UserExceptionVector.text, USER_VECTOR_VADDR)
-  SECTION_VECTOR (.DoubleExceptionVector.literal, DOUBLEEXC_VECTOR_VADDR - 20)
   SECTION_VECTOR (.DoubleExceptionVector.text, DOUBLEEXC_VECTOR_VADDR)
 #endif
 
+    IRQENTRY_TEXT
+    SOFTIRQENTRY_TEXT
+    ENTRY_TEXT
     TEXT_TEXT
-    VMLINUX_SYMBOL(__sched_text_start) = .;
-    *(.sched.literal .sched.text)
-    VMLINUX_SYMBOL(__sched_text_end) = .;
-    VMLINUX_SYMBOL(__cpuidle_text_start) = .;
-    *(.cpuidle.literal .cpuidle.text)
-    VMLINUX_SYMBOL(__cpuidle_text_end) = .;
-    VMLINUX_SYMBOL(__lock_text_start) = .;
-    *(.spinlock.literal .spinlock.text)
-    VMLINUX_SYMBOL(__lock_text_end) = .;
+    SCHED_TEXT
+    CPUIDLE_TEXT
+    LOCK_TEXT
 
   }
   _etext = .;
@@ -196,8 +181,6 @@ SECTIONS
                   .KernelExceptionVector.text);
     RELOCATE_ENTRY(_UserExceptionVector_text,
                   .UserExceptionVector.text);
-    RELOCATE_ENTRY(_DoubleExceptionVector_literal,
-                  .DoubleExceptionVector.literal);
     RELOCATE_ENTRY(_DoubleExceptionVector_text,
                   .DoubleExceptionVector.text);
     RELOCATE_ENTRY(_DebugInterruptVector_text,
@@ -230,25 +213,19 @@ SECTIONS
 
   SECTION_VECTOR (_WindowVectors_text,
                  .WindowVectors.text,
-                 WINDOW_VECTORS_VADDR, 4,
+                 WINDOW_VECTORS_VADDR,
                  .dummy)
-  SECTION_VECTOR (_DebugInterruptVector_literal,
-                 .DebugInterruptVector.literal,
-                 DEBUG_VECTOR_VADDR - 4,
-                 SIZEOF(.WindowVectors.text),
-                 .WindowVectors.text)
   SECTION_VECTOR (_DebugInterruptVector_text,
                  .DebugInterruptVector.text,
                  DEBUG_VECTOR_VADDR,
-                 4,
-                 .DebugInterruptVector.literal)
+                 .WindowVectors.text)
 #undef LAST
 #define LAST   .DebugInterruptVector.text
 #if XCHAL_EXCM_LEVEL >= 2
   SECTION_VECTOR (_Level2InterruptVector_text,
                  .Level2InterruptVector.text,
                  INTLEVEL2_VECTOR_VADDR,
-                 SIZEOF(LAST), LAST)
+                 LAST)
 # undef LAST
 # define LAST  .Level2InterruptVector.text
 #endif
@@ -256,7 +233,7 @@ SECTIONS
   SECTION_VECTOR (_Level3InterruptVector_text,
                  .Level3InterruptVector.text,
                  INTLEVEL3_VECTOR_VADDR,
-                 SIZEOF(LAST), LAST)
+                 LAST)
 # undef LAST
 # define LAST  .Level3InterruptVector.text
 #endif
@@ -264,7 +241,7 @@ SECTIONS
   SECTION_VECTOR (_Level4InterruptVector_text,
                  .Level4InterruptVector.text,
                  INTLEVEL4_VECTOR_VADDR,
-                 SIZEOF(LAST), LAST)
+                 LAST)
 # undef LAST
 # define LAST  .Level4InterruptVector.text
 #endif
@@ -272,7 +249,7 @@ SECTIONS
   SECTION_VECTOR (_Level5InterruptVector_text,
                  .Level5InterruptVector.text,
                  INTLEVEL5_VECTOR_VADDR,
-                 SIZEOF(LAST), LAST)
+                 LAST)
 # undef LAST
 # define LAST  .Level5InterruptVector.text
 #endif
@@ -280,40 +257,23 @@ SECTIONS
   SECTION_VECTOR (_Level6InterruptVector_text,
                  .Level6InterruptVector.text,
                  INTLEVEL6_VECTOR_VADDR,
-                 SIZEOF(LAST), LAST)
+                 LAST)
 # undef LAST
 # define LAST  .Level6InterruptVector.text
 #endif
-  SECTION_VECTOR (_KernelExceptionVector_literal,
-                 .KernelExceptionVector.literal,
-                 KERNEL_VECTOR_VADDR - 4,
-                 SIZEOF(LAST), LAST)
-#undef LAST
   SECTION_VECTOR (_KernelExceptionVector_text,
                  .KernelExceptionVector.text,
                  KERNEL_VECTOR_VADDR,
-                 4,
-                 .KernelExceptionVector.literal)
-  SECTION_VECTOR (_UserExceptionVector_literal,
-                 .UserExceptionVector.literal,
-                 USER_VECTOR_VADDR - 4,
-                 SIZEOF(.KernelExceptionVector.text),
-                 .KernelExceptionVector.text)
+                 LAST)
+#undef LAST
   SECTION_VECTOR (_UserExceptionVector_text,
                  .UserExceptionVector.text,
                  USER_VECTOR_VADDR,
-                 4,
-                 .UserExceptionVector.literal)
-  SECTION_VECTOR (_DoubleExceptionVector_literal,
-                 .DoubleExceptionVector.literal,
-                 DOUBLEEXC_VECTOR_VADDR - 20,
-                 SIZEOF(.UserExceptionVector.text),
-                 .UserExceptionVector.text)
+                 .KernelExceptionVector.text)
   SECTION_VECTOR (_DoubleExceptionVector_text,
                  .DoubleExceptionVector.text,
                  DOUBLEEXC_VECTOR_VADDR,
-                 20,
-                 .DoubleExceptionVector.literal)
+                 .UserExceptionVector.text)
 
   . = (LOADADDR( .DoubleExceptionVector.text ) + SIZEOF( .DoubleExceptionVector.text ) + 3) & ~ 3;
 
@@ -323,7 +283,6 @@ SECTIONS
   SECTION_VECTOR (_SecondaryResetVector_text,
                  .SecondaryResetVector.text,
                  RESET_VECTOR1_VADDR,
-                 SIZEOF(.DoubleExceptionVector.text),
                  .DoubleExceptionVector.text)
 
   . = LOADADDR(.SecondaryResetVector.text)+SIZEOF(.SecondaryResetVector.text);
@@ -373,5 +332,4 @@ SECTIONS
 
   /* Sections to be discarded */
   DISCARDS
-  /DISCARD/ : { *(.exit.literal) }
 }