xtensa: only build windowed register support code when needed

There's no need in window overflow/underflow/alloca exception handlers
or window spill code when neither kernel nor userspace support windowed
registers. Don't build or link it.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

diff --git a/arch/xtensa/include/asm/traps.h b/arch/xtensa/include/asm/traps.h
index f720a57d0a5bb0613c623b4bb894789423f0f5d9..6fa47cd8e02d44ef88b93b235edf094dec0971f4 100644 (file)
--- a/arch/xtensa/include/asm/traps.h
+++ b/arch/xtensa/include/asm/traps.h
@@ -56,6 +56,7 @@ void secondary_trap_init(void);
 
 static inline void spill_registers(void)
 {
+#if defined(__XTENSA_WINDOWED_ABI__)
 #if XCHAL_NUM_AREGS > 16
        __asm__ __volatile__ (
                "       call8   1f\n"
@@ -96,6 +97,7 @@ static inline void spill_registers(void)
                "       mov     a12, a12\n"
                : : : "memory");
 #endif
+#endif
 }
 
 struct debug_table {

diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 8029ce24af925eb666b7bc7070ef39b213bbfc9b..99ab3c1a33873aa7404d90d397194dc5a437e3a5 100644 (file)
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -969,6 +969,7 @@ ENDPROC(unrecoverable_exception)
        __XTENSA_HANDLER
        .literal_position
 
+#ifdef SUPPORT_WINDOWED
 /*
  * Fast-handler for alloca exceptions
  *
@@ -1032,6 +1033,7 @@ ENTRY(fast_alloca)
 8:     j       _WindowUnderflow8
 4:     j       _WindowUnderflow4
 ENDPROC(fast_alloca)
+#endif
 
 #ifdef CONFIG_USER_ABI_CALL0_PROBE
 /*
@@ -1228,7 +1230,8 @@ ENDPROC(fast_syscall_xtensa)
  * Note: We assume the stack pointer is EXC_TABLE_KSTK in the fixup handler.
  */
 
-#ifdef CONFIG_FAST_SYSCALL_SPILL_REGISTERS
+#if defined(CONFIG_FAST_SYSCALL_SPILL_REGISTERS) && \
+               defined(USER_SUPPORT_WINDOWED)
 
 ENTRY(fast_syscall_spill_registers)
 

diff --git a/arch/xtensa/kernel/setup.c b/arch/xtensa/kernel/setup.c
index ee9082a142feb49cf187c014df9d6df8b605a939..ad665e8c94168bfa1b87145dbd8c12cf5c6bf570 100644 (file)
--- a/arch/xtensa/kernel/setup.c
+++ b/arch/xtensa/kernel/setup.c
@@ -349,8 +349,10 @@ void __init setup_arch(char **cmdline_p)
 #endif
 
 #ifdef CONFIG_VECTORS_ADDR
+#ifdef SUPPORT_WINDOWED
        mem_reserve(__pa(&_WindowVectors_text_start),
                    __pa(&_WindowVectors_text_end));
+#endif
 
        mem_reserve(__pa(&_DebugInterruptVector_text_start),
                    __pa(&_DebugInterruptVector_text_end));

diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c
index c4d77dbfb61afcf3f94ad8b12f0b9345586387a9..f6c949895b3eb197bcf05b6b1610f860d4304446 100644 (file)
--- a/arch/xtensa/kernel/signal.c
+++ b/arch/xtensa/kernel/signal.c
@@ -45,12 +45,13 @@ struct rt_sigframe
        unsigned int window[4];
 };
 
-/* 
+#if defined(USER_SUPPORT_WINDOWED)
+/*
  * Flush register windows stored in pt_regs to stack.
  * Returns 1 for errors.
  */
 
-int
+static int
 flush_window_regs_user(struct pt_regs *regs)
 {
        const unsigned long ws = regs->windowstart;
@@ -121,6 +122,13 @@ flush_window_regs_user(struct pt_regs *regs)
 errout:
        return err;
 }
+#else
+static int
+flush_window_regs_user(struct pt_regs *regs)
+{
+       return 0;
+}
+#endif
 
 /*
  * Note: We don't copy double exception 'regs', we have to finish double exc. 

diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c
index 874b6efc6fb3193ee0aacd1ed7c6f36f8d930cd0..4418438b13e63e2d2240a61d33f20b37c723da36 100644 (file)
--- a/arch/xtensa/kernel/traps.c
+++ b/arch/xtensa/kernel/traps.c
@@ -97,7 +97,9 @@ static dispatch_init_table_t __initdata dispatch_init_table[] = {
 /* EXCCAUSE_INSTRUCTION_FETCH unhandled */
 /* EXCCAUSE_LOAD_STORE_ERROR unhandled*/
 { EXCCAUSE_LEVEL1_INTERRUPT,   0,         do_interrupt },
+#ifdef SUPPORT_WINDOWED
 { EXCCAUSE_ALLOCA,             USER|KRNL, fast_alloca },
+#endif
 /* EXCCAUSE_INTEGER_DIVIDE_BY_ZERO unhandled */
 /* EXCCAUSE_PRIVILEGED unhandled */
 #if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION

diff --git a/arch/xtensa/kernel/vectors.S b/arch/xtensa/kernel/vectors.S
index 0eed5aa82914ea7a87c30eb89e73872a49db48c9..407ece204e7caad11c6f070a28b2977d1b60a7e8 100644 (file)
--- a/arch/xtensa/kernel/vectors.S
+++ b/arch/xtensa/kernel/vectors.S
@@ -226,6 +226,7 @@ ENTRY(_DoubleExceptionVector)
 
        xsr     a0, depc                # get DEPC, save a0
 
+#ifdef SUPPORT_WINDOWED
        movi    a2, WINDOW_VECTORS_VADDR
        _bltu   a0, a2, .Lfixup
        addi    a2, a2, WINDOW_VECTORS_SIZE
@@ -275,6 +276,10 @@ _DoubleExceptionVector_WindowUnderflow:
        l32i    a0, a0, EXC_TABLE_FAST_USER
        jx      a0
 
+#else
+       j       .Lfixup
+#endif
+
        /*
         * We only allow the ITLB miss exception if we are in kernel space.
         * All other exceptions are unexpected and thus unrecoverable!
@@ -343,6 +348,7 @@ _DoubleExceptionVector_WindowUnderflow:
        l32i    a0, a0, EXC_TABLE_FAST_USER
        jx      a0
 
+#ifdef SUPPORT_WINDOWED
        /*
         * Restart window OVERFLOW exception.
         * Currently:
@@ -475,9 +481,12 @@ _DoubleExceptionVector_handle_exception:
        rsr     a0, depc
        rotw    -3
        j       1b
+#endif
 
 ENDPROC(_DoubleExceptionVector)
 
+#ifdef SUPPORT_WINDOWED
+
 /*
  * Fixup handler for TLB miss in double exception handler for window owerflow.
  * We get here with windowbase set to the window that was being spilled and
@@ -590,6 +599,8 @@ ENTRY(window_overflow_restore_a0_fixup)
 
 ENDPROC(window_overflow_restore_a0_fixup)
 
+#endif
+
 /*
  * Debug interrupt vector
  *
@@ -687,6 +698,8 @@ _SimulateUserKernelVectorException:
        .section                .WindowVectors.text, "ax"
 
 
+#ifdef SUPPORT_WINDOWED
+
 /* 4-Register Window Overflow Vector (Handler) */
 
 ENTRY_ALIGN64(_WindowOverflow4)
@@ -787,4 +800,6 @@ ENTRY_ALIGN64(_WindowUnderflow12)
 
 ENDPROC(_WindowUnderflow12)
 
+#endif
+
        .text

diff --git a/arch/xtensa/kernel/vmlinux.lds.S b/arch/xtensa/kernel/vmlinux.lds.S
index d23a6e38f06253d0d21970c92f9da821627eac77..eee270a039a46043c9750fd5f2ec8997a41e2fa0 100644 (file)
--- a/arch/xtensa/kernel/vmlinux.lds.S
+++ b/arch/xtensa/kernel/vmlinux.lds.S
@@ -94,7 +94,9 @@ SECTIONS
     . = ALIGN(PAGE_SIZE);
     _vecbase = .;
 
+#ifdef SUPPORT_WINDOWED
     SECTION_VECTOR2 (.WindowVectors.text, WINDOW_VECTORS_VADDR)
+#endif
 #if XCHAL_EXCM_LEVEL >= 2
     SECTION_VECTOR2 (.Level2InterruptVector.text, INTLEVEL2_VECTOR_VADDR)
 #endif
@@ -166,8 +168,10 @@ SECTIONS
     __boot_reloc_table_start = ABSOLUTE(.);
 
 #if !MERGED_VECTORS
+#ifdef SUPPORT_WINDOWED
     RELOCATE_ENTRY(_WindowVectors_text,
                   .WindowVectors.text);
+#endif
 #if XCHAL_EXCM_LEVEL >= 2
     RELOCATE_ENTRY(_Level2InterruptVector_text,
                   .Level2InterruptVector.text);
@@ -229,14 +233,18 @@ SECTIONS
 #if !MERGED_VECTORS
   /* The vectors are relocated to the real position at startup time */
 
+#ifdef SUPPORT_WINDOWED
   SECTION_VECTOR4 (_WindowVectors_text,
                  .WindowVectors.text,
                  WINDOW_VECTORS_VADDR,
-                 .dummy)
+                 LAST)
+#undef LAST
+#define LAST   .WindowVectors.text
+#endif
   SECTION_VECTOR4 (_DebugInterruptVector_text,
                  .DebugInterruptVector.text,
                  DEBUG_VECTOR_VADDR,
-                 .WindowVectors.text)
+                 LAST)
 #undef LAST
 #define LAST   .DebugInterruptVector.text
 #if XCHAL_EXCM_LEVEL >= 2