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-rw-r--r--arch/powerpc/kernel/head_64.S71
1 files changed, 55 insertions, 16 deletions
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 27935d1ab6a..97bb6e6f67b 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -82,7 +82,11 @@ END_FTR_SECTION(0, 1)
/* Catch branch to 0 in real mode */
trap
- /* Secondary processors spin on this value until it goes to 1. */
+ /* Secondary processors spin on this value until it becomes nonzero.
+ * When it does it contains the real address of the descriptor
+ * of the function that the cpu should jump to to continue
+ * initialization.
+ */
.globl __secondary_hold_spinloop
__secondary_hold_spinloop:
.llong 0x0
@@ -109,8 +113,11 @@ __secondary_hold_acknowledge:
* before the bulk of the kernel has been relocated. This code
* is relocated to physical address 0x60 before prom_init is run.
* All of it must fit below the first exception vector at 0x100.
+ * Use .globl here not _GLOBAL because we want __secondary_hold
+ * to be the actual text address, not a descriptor.
*/
-_GLOBAL(__secondary_hold)
+ .globl __secondary_hold
+__secondary_hold:
mfmsr r24
ori r24,r24,MSR_RI
mtmsrd r24 /* RI on */
@@ -126,11 +133,11 @@ _GLOBAL(__secondary_hold)
/* All secondary cpus wait here until told to start. */
100: ld r4,__secondary_hold_spinloop@l(0)
- cmpdi 0,r4,1
- bne 100b
+ cmpdi 0,r4,0
+ beq 100b
#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
- LOAD_REG_IMMEDIATE(r4, .generic_secondary_smp_init)
+ ld r4,0(r4) /* deref function descriptor */
mtctr r4
mr r3,r24
bctr
@@ -147,6 +154,10 @@ exception_marker:
/*
* This is the start of the interrupt handlers for pSeries
* This code runs with relocation off.
+ * Code from here to __end_interrupts gets copied down to real
+ * address 0x100 when we are running a relocatable kernel.
+ * Therefore any relative branches in this section must only
+ * branch to labels in this section.
*/
. = 0x100
.globl __start_interrupts
@@ -200,7 +211,20 @@ data_access_slb_pSeries:
mfspr r10,SPRN_SPRG1
std r10,PACA_EXSLB+EX_R13(r13)
mfspr r12,SPRN_SRR1 /* and SRR1 */
- b .slb_miss_realmode /* Rel. branch works in real mode */
+#ifndef CONFIG_RELOCATABLE
+ b .slb_miss_realmode
+#else
+ /*
+ * We can't just use a direct branch to .slb_miss_realmode
+ * because the distance from here to there depends on where
+ * the kernel ends up being put.
+ */
+ mfctr r11
+ ld r10,PACAKBASE(r13)
+ LOAD_HANDLER(r10, .slb_miss_realmode)
+ mtctr r10
+ bctr
+#endif
STD_EXCEPTION_PSERIES(0x400, instruction_access)
@@ -225,7 +249,15 @@ instruction_access_slb_pSeries:
mfspr r10,SPRN_SPRG1
std r10,PACA_EXSLB+EX_R13(r13)
mfspr r12,SPRN_SRR1 /* and SRR1 */
- b .slb_miss_realmode /* Rel. branch works in real mode */
+#ifndef CONFIG_RELOCATABLE
+ b .slb_miss_realmode
+#else
+ mfctr r11
+ ld r10,PACAKBASE(r13)
+ LOAD_HANDLER(r10, .slb_miss_realmode)
+ mtctr r10
+ bctr
+#endif
MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt)
STD_EXCEPTION_PSERIES(0x600, alignment)
@@ -244,14 +276,12 @@ BEGIN_FTR_SECTION
beq- 1f
END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)
mr r9,r13
- mfmsr r10
mfspr r13,SPRN_SPRG3
mfspr r11,SPRN_SRR0
- clrrdi r12,r13,32
- oris r12,r12,system_call_common@h
- ori r12,r12,system_call_common@l
+ ld r12,PACAKBASE(r13)
+ ld r10,PACAKMSR(r13)
+ LOAD_HANDLER(r12, system_call_entry)
mtspr SPRN_SRR0,r12
- ori r10,r10,MSR_IR|MSR_DR|MSR_RI
mfspr r12,SPRN_SRR1
mtspr SPRN_SRR1,r10
rfid
@@ -379,7 +409,10 @@ __end_interrupts:
/*
* Code from here down to __end_handlers is invoked from the
- * exception prologs above.
+ * exception prologs above. Because the prologs assemble the
+ * addresses of these handlers using the LOAD_HANDLER macro,
+ * which uses an addi instruction, these handlers must be in
+ * the first 32k of the kernel image.
*/
/*** Common interrupt handlers ***/
@@ -419,6 +452,10 @@ machine_check_common:
STD_EXCEPTION_COMMON(0x1800, cbe_thermal, .cbe_thermal_exception)
#endif /* CONFIG_CBE_RAS */
+ .align 7
+system_call_entry:
+ b system_call_common
+
/*
* Here we have detected that the kernel stack pointer is bad.
* R9 contains the saved CR, r13 points to the paca,
@@ -562,6 +599,9 @@ unrecov_user_slb:
*/
_GLOBAL(slb_miss_realmode)
mflr r10
+#ifdef CONFIG_RELOCATABLE
+ mtctr r11
+#endif
stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */
std r10,PACA_EXSLB+EX_LR(r13) /* save LR */
@@ -612,11 +652,10 @@ BEGIN_FW_FTR_SECTION
END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES)
#endif /* CONFIG_PPC_ISERIES */
mfspr r11,SPRN_SRR0
- clrrdi r10,r13,32
+ ld r10,PACAKBASE(r13)
LOAD_HANDLER(r10,unrecov_slb)
mtspr SPRN_SRR0,r10
- mfmsr r10
- ori r10,r10,MSR_IR|MSR_DR|MSR_RI
+ ld r10,PACAKMSR(r13)
mtspr SPRN_SRR1,r10
rfid
b .