powerpc: ABIv2 function calls must place target address in r12

To establish addressability quickly, ABIv2 requires the target
address of the function being called to be in r12. Fix a number of
places in assembly code that we do indirect function calls.

We need to avoid function descriptors on ABIv2 too.

Signed-off-by: Anton Blanchard <anton@samba.org>

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 2662f02ba6cfe03f76615d5db17ee6a48ffae4b8..d23d7526d37a1693c2070dad0b68f3a5c36119e1 100644 (file)
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -174,8 +174,8 @@ system_call:                        /* label this so stack traces look sane */
        clrldi  r8,r8,32
 15:
        slwi    r0,r0,4
-       ldx     r10,r11,r0      /* Fetch system call handler [ptr] */
-       mtctr   r10
+       ldx     r12,r11,r0      /* Fetch system call handler [ptr] */
+       mtctr   r12
        bctrl                   /* Call handler */
 
 syscall_exit:

diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 82841242dc26a783c5ddd9692542fb3d67da9497..97329a19c76bacf771b221027d129ef02e20de48 100644 (file)
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -140,16 +140,18 @@ __secondary_hold:
        tovirt(r26,r26)
 #endif
        /* All secondary cpus wait here until told to start. */
-100:   ld      r4,__secondary_hold_spinloop-_stext(r26)
-       cmpdi   0,r4,0
+100:   ld      r12,__secondary_hold_spinloop-_stext(r26)
+       cmpdi   0,r12,0
        beq     100b
 
 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
 #ifdef CONFIG_PPC_BOOK3E
-       tovirt(r4,r4)
+       tovirt(r12,r12)
 #endif
-       ld      r4,0(r4)                /* deref function descriptor */
-       mtctr   r4
+#if !defined(_CALL_ELF) || _CALL_ELF != 2
+       ld      r12,0(r12)              /* deref function descriptor */
+#endif
+       mtctr   r12
        mr      r3,r24
        /*
         * it may be the case that other platforms have r4 right to
@@ -267,8 +269,8 @@ generic_secondary_common_init:
        ld      r23,CPU_SPEC_RESTORE(r23)
        cmpdi   0,r23,0
        beq     3f
-       ld      r23,0(r23)
-       mtctr   r23
+       ld      r12,0(r23)
+       mtctr   r12
        bctrl
 
 3:     LOAD_REG_ADDR(r3, spinning_secondaries) /* Decrement spinning_secondaries */
@@ -468,8 +470,8 @@ __after_prom_start:
                                        /* this includes the code being  */
                                        /* executed here.                */
        addis   r8,r3,(4f - _stext)@ha  /* Jump to the copy of this code */
-       addi    r8,r8,(4f - _stext)@l   /* that we just made */
-       mtctr   r8
+       addi    r12,r8,(4f - _stext)@l  /* that we just made */
+       mtctr   r12
        bctr
 
 .balign 8

diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index b39cf4afad4b3a5819e3f51cb3a7a1f61f53a7c7..bda85a193abf611a4134f44e79cbc1186484e016 100644 (file)
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -595,8 +595,12 @@ _GLOBAL(kexec_sequence)
        stw     r6,kexec_flag-1b(5)
 
        /* clear out hardware hash page table and tlb */
-       ld      r5,0(r27)               /* deref function descriptor */
-       mtctr   r5
+#if !defined(_CALL_ELF) || _CALL_ELF != 2
+       ld      r12,0(r27)              /* deref function descriptor */
+#else
+       mr      r12,r27
+#endif
+       mtctr   r12
        bctrl                           /* ppc_md.hpte_clear_all(void); */
 
 /*