sparc64: Fix bootup regressions on some Kconfig combinations.

The system call tracing bug fix mentioned in the Fixes tag
below increased the amount of assembler code in the sequence
of assembler files included by head_64.S

This caused to total set of code to exceed 0x4000 bytes in
size, which overflows the expression in head_64.S that works
to place swapper_tsb at address 0x408000.

When this is violated, the TSB is not properly aligned, and
also the trap table is not aligned properly either.  All of
this together results in failed boots.

So, do two things:

1) Simplify some code by using ba,a instead of ba/nop to get
   those bytes back.

2) Add a linker script assertion to make sure that if this
   happens again the build will fail.

Fixes: 1a40b95374f6 ("sparc: Fix system call tracing register handling.")
Reported-by: Meelis Roos <mroos@linux.ee>
Reported-by: Joerg Abraham <joerg.abraham@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 34 insertions, 55 deletions

diff --git a/arch/sparc/kernel/cherrs.S b/arch/sparc/kernel/cherrs.S
index 4ee1ad4..655628de 100644
--- a/arch/sparc/kernel/cherrs.S
+++ b/arch/sparc/kernel/cherrs.S
@@ -214,8 +214,7 @@ do_dcpe_tl1_nonfatal:	/* Ok we may use interrupt globals safely. */
 	subcc		%g1, %g2, %g1		! Next cacheline
 	bge,pt		%icc, 1b
 	 nop
-	ba,pt		%xcc, dcpe_icpe_tl1_common
-	 nop
+	ba,a,pt		%xcc, dcpe_icpe_tl1_common
 
 do_dcpe_tl1_fatal:
 	sethi		%hi(1f), %g7
@@ -224,8 +223,7 @@ do_dcpe_tl1_fatal:
 	mov		0x2, %o0
 	call		cheetah_plus_parity_error
 	 add		%sp, PTREGS_OFF, %o1
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		do_dcpe_tl1,.-do_dcpe_tl1
 
 	.globl		do_icpe_tl1
@@ -259,8 +257,7 @@ do_icpe_tl1_nonfatal:	/* Ok we may use interrupt globals safely. */
 	subcc		%g1, %g2, %g1
 	bge,pt		%icc, 1b
 	 nop
-	ba,pt		%xcc, dcpe_icpe_tl1_common
-	 nop
+	ba,a,pt		%xcc, dcpe_icpe_tl1_common
 
 do_icpe_tl1_fatal:
 	sethi		%hi(1f), %g7
@@ -269,8 +266,7 @@ do_icpe_tl1_fatal:
 	mov		0x3, %o0
 	call		cheetah_plus_parity_error
 	 add		%sp, PTREGS_OFF, %o1
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		do_icpe_tl1,.-do_icpe_tl1
 	
 	.type		dcpe_icpe_tl1_common,#function
@@ -456,7 +452,7 @@ __cheetah_log_error:
 	 cmp		%g2, 0x63
 	be		c_cee
 	 nop
-	ba,pt		%xcc, c_deferred
+	ba,a,pt		%xcc, c_deferred
 	.size		__cheetah_log_error,.-__cheetah_log_error
 
 	/* Cheetah FECC trap handling, we get here from tl{0,1}_fecc
diff --git a/arch/sparc/kernel/fpu_traps.S b/arch/sparc/kernel/fpu_traps.S
index a686482..336d275 100644
--- a/arch/sparc/kernel/fpu_traps.S
+++ b/arch/sparc/kernel/fpu_traps.S
@@ -100,8 +100,8 @@ do_fpdis:
 	fmuld		%f0, %f2, %f26
 	faddd		%f0, %f2, %f28
 	fmuld		%f0, %f2, %f30
-	b,pt		%xcc, fpdis_exit
-	 nop
+	ba,a,pt		%xcc, fpdis_exit
+
 2:	andcc		%g5, FPRS_DU, %g0
 	bne,pt		%icc, 3f
 	 fzero		%f32
@@ -144,8 +144,8 @@ do_fpdis:
 	fmuld		%f32, %f34, %f58
 	faddd		%f32, %f34, %f60
 	fmuld		%f32, %f34, %f62
-	ba,pt		%xcc, fpdis_exit
-	 nop
+	ba,a,pt		%xcc, fpdis_exit
+
 3:	mov		SECONDARY_CONTEXT, %g3
 	add		%g6, TI_FPREGS, %g1
 
@@ -197,8 +197,7 @@ fpdis_exit2:
 fp_other_bounce:
 	call		do_fpother
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		fp_other_bounce,.-fp_other_bounce
 
 	.align		32
diff --git a/arch/sparc/kernel/head_64.S b/arch/sparc/kernel/head_64.S
index 5b4f5c36..a076b42 100644
--- a/arch/sparc/kernel/head_64.S
+++ b/arch/sparc/kernel/head_64.S
@@ -466,9 +466,8 @@ sun4v_chip_type:
 	subcc	%g3, 1, %g3
 	bne,pt	%xcc, 41b
 	add	%g1, 1, %g1
-	mov	SUN4V_CHIP_SPARC64X, %g4
 	ba,pt	%xcc, 5f
-	nop
+	 mov	SUN4V_CHIP_SPARC64X, %g4
 
 49:
 	mov	SUN4V_CHIP_UNKNOWN, %g4
@@ -553,8 +552,7 @@ sun4u_init:
 	stxa		%g0, [%g7] ASI_DMMU
 	membar	#Sync
 
-	ba,pt		%xcc, sun4u_continue
-	 nop
+	ba,a,pt		%xcc, sun4u_continue
 
 sun4v_init:
 	/* Set ctx 0 */
@@ -565,14 +563,12 @@ sun4v_init:
 	mov		SECONDARY_CONTEXT, %g7
 	stxa		%g0, [%g7] ASI_MMU
 	membar		#Sync
-	ba,pt		%xcc, niagara_tlb_fixup
-	 nop
+	ba,a,pt		%xcc, niagara_tlb_fixup
 
 sun4u_continue:
 	BRANCH_IF_ANY_CHEETAH(g1, g7, cheetah_tlb_fixup)
 
-	ba,pt	%xcc, spitfire_tlb_fixup
-	 nop
+	ba,a,pt	%xcc, spitfire_tlb_fixup
 
 niagara_tlb_fixup:
 	mov	3, %g2		/* Set TLB type to hypervisor. */
@@ -647,8 +643,7 @@ niagara_patch:
 	call	hypervisor_patch_cachetlbops
 	 nop
 
-	ba,pt	%xcc, tlb_fixup_done
-	 nop
+	ba,a,pt	%xcc, tlb_fixup_done
 
 cheetah_tlb_fixup:
 	mov	2, %g2		/* Set TLB type to cheetah+. */
@@ -667,8 +662,7 @@ cheetah_tlb_fixup:
 	call	cheetah_patch_cachetlbops
 	 nop
 
-	ba,pt	%xcc, tlb_fixup_done
-	 nop
+	ba,a,pt	%xcc, tlb_fixup_done
 
 spitfire_tlb_fixup:
 	/* Set TLB type to spitfire. */
@@ -782,8 +776,7 @@ setup_trap_table:
 	call	%o1
 	 add	%sp, (2047 + 128), %o0
 
-	ba,pt	%xcc, 2f
-	 nop
+	ba,a,pt	%xcc, 2f
 
 1:	sethi	%hi(sparc64_ttable_tl0), %o0
 	set	prom_set_trap_table_name, %g2
@@ -822,8 +815,7 @@ setup_trap_table:
 
 	BRANCH_IF_ANY_CHEETAH(o2, o3, 1f)
 
-	ba,pt	%xcc, 2f
-	 nop
+	ba,a,pt	%xcc, 2f
 
 	/* Disable STICK_INT interrupts. */
 1:
diff --git a/arch/sparc/kernel/misctrap.S b/arch/sparc/kernel/misctrap.S
index 753b4f0..34b4933 100644
--- a/arch/sparc/kernel/misctrap.S
+++ b/arch/sparc/kernel/misctrap.S
@@ -18,8 +18,7 @@ __do_privact:
 109:	or		%g7, %lo(109b), %g7
 	call		do_privact
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		__do_privact,.-__do_privact
 
 	.type		do_mna,#function
@@ -46,8 +45,7 @@ do_mna:
 	mov		%l5, %o2
 	call		mem_address_unaligned
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		do_mna,.-do_mna
 
 	.type		do_lddfmna,#function
@@ -65,8 +63,7 @@ do_lddfmna:
 	mov		%l5, %o2
 	call		handle_lddfmna
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		do_lddfmna,.-do_lddfmna
 
 	.type		do_stdfmna,#function
@@ -84,8 +81,7 @@ do_stdfmna:
 	mov		%l5, %o2
 	call		handle_stdfmna
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		do_stdfmna,.-do_stdfmna
 
 	.type		breakpoint_trap,#function
diff --git a/arch/sparc/kernel/spiterrs.S b/arch/sparc/kernel/spiterrs.S
index c357e40..4a73009 100644
--- a/arch/sparc/kernel/spiterrs.S
+++ b/arch/sparc/kernel/spiterrs.S
@@ -85,8 +85,7 @@ __spitfire_cee_trap_continue:
 	ba,pt		%xcc, etraptl1
 	 rd		%pc, %g7
 
-	ba,pt		%xcc, 2f
-	 nop
+	ba,a,pt		%xcc, 2f
 
 1:	ba,pt		%xcc, etrap_irq
 	 rd		%pc, %g7
@@ -100,8 +99,7 @@ __spitfire_cee_trap_continue:
 	mov		%l5, %o2
 	call		spitfire_access_error
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		__spitfire_access_error,.-__spitfire_access_error
 
 	/* This is the trap handler entry point for ECC correctable
@@ -179,8 +177,7 @@ __spitfire_data_access_exception_tl1:
 	mov		%l5, %o2
 	call		spitfire_data_access_exception_tl1
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		__spitfire_data_access_exception_tl1,.-__spitfire_data_access_exception_tl1
 
 	.type		__spitfire_data_access_exception,#function
@@ -200,8 +197,7 @@ __spitfire_data_access_exception:
 	mov		%l5, %o2
 	call		spitfire_data_access_exception
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		__spitfire_data_access_exception,.-__spitfire_data_access_exception
 
 	.type		__spitfire_insn_access_exception_tl1,#function
@@ -220,8 +216,7 @@ __spitfire_insn_access_exception_tl1:
 	mov		%l5, %o2
 	call		spitfire_insn_access_exception_tl1
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		__spitfire_insn_access_exception_tl1,.-__spitfire_insn_access_exception_tl1
 
 	.type		__spitfire_insn_access_exception,#function
@@ -240,6 +235,5 @@ __spitfire_insn_access_exception:
 	mov		%l5, %o2
 	call		spitfire_insn_access_exception
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 	.size		__spitfire_insn_access_exception,.-__spitfire_insn_access_exception
diff --git a/arch/sparc/kernel/utrap.S b/arch/sparc/kernel/utrap.S
index b7f0f3f..c731e80 100644
--- a/arch/sparc/kernel/utrap.S
+++ b/arch/sparc/kernel/utrap.S
@@ -11,8 +11,7 @@ utrap_trap:		/* %g3=handler,%g4=level */
 	mov		%l4, %o1
         call		bad_trap
 	 add		%sp, PTREGS_OFF, %o0
-	ba,pt		%xcc, rtrap
-	 nop
+	ba,a,pt		%xcc, rtrap
 
 invoke_utrap:
 	sllx		%g3, 3, %g3
diff --git a/arch/sparc/kernel/vmlinux.lds.S b/arch/sparc/kernel/vmlinux.lds.S
index aadd321..7d02b1f 100644
--- a/arch/sparc/kernel/vmlinux.lds.S
+++ b/arch/sparc/kernel/vmlinux.lds.S
@@ -33,6 +33,10 @@ ENTRY(_start)
 jiffies = jiffies_64;
 #endif
 
+#ifdef CONFIG_SPARC64
+ASSERT((swapper_tsb == 0x0000000000408000), "Error: sparc64 early assembler too large")
+#endif
+
 SECTIONS
 {
 #ifdef CONFIG_SPARC64
diff --git a/arch/sparc/kernel/winfixup.S b/arch/sparc/kernel/winfixup.S
index 1e67ce9..855019a 100644
--- a/arch/sparc/kernel/winfixup.S
+++ b/arch/sparc/kernel/winfixup.S
@@ -32,8 +32,7 @@ fill_fixup:
 	 rd	%pc, %g7
 	call	do_sparc64_fault
 	 add	%sp, PTREGS_OFF, %o0
-	ba,pt	%xcc, rtrap
-	 nop
+	ba,a,pt	%xcc, rtrap
 
 	/* Be very careful about usage of the trap globals here.
 	 * You cannot touch %g5 as that has the fault information.