sparc: prepare kernel/ for unification

o sparc32 files with identical names to sparc64 renamed to <name>_32.S
o introduced a few Kconfig helpers to simplify Makefile logic
o refactored Makefile to prepare for unification
  - use obj-$(CONFIG_SPARC32) for sparc32 specific files
  - use <name>_$(BITS) for files where sparc64 has a _64 variant
  - sparc64 directly include a few files where sparc32 builds them,
    refer to these files directly (no BITS)
  - sneaked in -Werror as used by sparc64
o modified sparc/Makefile to use the new names for head/init_task

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/Kconfig

@@ -198,6 +198,17 @@ config EMULATED_CMPXCHG
 	  Sparc32 does not have a CAS instruction like sparc64. cmpxchg()
 	  is emulated, and therefore it is not completely atomic.
 
+# Makefile helpers
+config SPARC32_SMP
+	bool
+	default y
+	depends on SPARC32 && SMP
+
+config SPARC64_SMP
+	bool
+	default y
+	depends on SPARC64 && SMP
+
 choice
 	prompt "Kernel page size" if SPARC64
 	default SPARC64_PAGE_SIZE_8KB
@@ -505,6 +516,16 @@ config SUN_OPENPROMFS
 	  Only choose N if you know in advance that you will not need to modify
 	  OpenPROM settings on the running system.
 
+# Makefile helpers
+config SPARC32_PCI
+	bool
+	default y
+	depends on SPARC32 && PCI
+
+config SPARC64_PCI
+	bool
+	default y
+	depends on SPARC64 && PCI
 
 endmenu
 

arch/sparc/Makefile

@@ -67,8 +67,8 @@ endif
 
 endif
 
-head-$(CONFIG_SPARC32) := arch/sparc/kernel/head.o
+head-$(CONFIG_SPARC32) := arch/sparc/kernel/head_$(BITS).o
-head-$(CONFIG_SPARC32) += arch/sparc/kernel/init_task.o
+head-$(CONFIG_SPARC32) += arch/sparc/kernel/init_task_$(BITS).o
 head-$(CONFIG_SPARC64) := arch/sparc64/kernel/head.o
 head-$(CONFIG_SPARC64) += arch/sparc64/kernel/init_task.o
 

arch/sparc/kernel/Makefile

@@ -2,25 +2,57 @@
 # Makefile for the linux kernel.
 #
 
-extra-y		:= head.o init_task.o vmlinux.lds
+asflags-y := -ansi
+ccflags-y := -Werror
 
-EXTRA_AFLAGS	:= -ansi
+extra-y     := head_$(BITS).o
+extra-y     += init_task_$(BITS).o
+extra-y     += vmlinux.lds
 
-IRQ_OBJS := irq.o sun4m_irq.o sun4c_irq.o sun4d_irq.o
+obj-$(CONFIG_SPARC32)   += entry.o wof.o wuf.o
-obj-y    := entry.o wof.o wuf.o etrap.o rtrap.o traps.o $(IRQ_OBJS) \
+obj-$(CONFIG_SPARC32)   += etrap_32.o
-	    process.o signal.o ioport.o setup.o idprom.o \
+obj-$(CONFIG_SPARC32)   += rtrap_32.o
-	    sys_sparc.o systbls.o \
+obj-y                   += traps_$(BITS).o
-	    time.o windows.o cpu.o devices.o \
-	    tadpole.o tick14.o ptrace.o \
-	    unaligned.o una_asm.o muldiv.o \
-	    prom.o of_device.o devres.o dma.o
 
-devres-y = ../../../kernel/irq/devres.o
+# IRQ
+obj-y                   += irq_$(BITS).o
+obj-$(CONFIG_SPARC32)   += sun4m_irq.o sun4c_irq.o sun4d_irq.o
 
-obj-$(CONFIG_PCI) += pcic.o
+obj-y                   += process_$(BITS).o
-obj-$(CONFIG_SMP) += trampoline.o smp.o sun4m_smp.o sun4d_smp.o
+obj-y                   += signal_$(BITS).o
-obj-$(CONFIG_SUN_AUXIO) += auxio.o
+obj-$(CONFIG_SPARC32)   += ioport.o
-obj-$(CONFIG_SUN_PM) += apc.o pmc.o
+obj-y                   += setup_$(BITS).o
-obj-$(CONFIG_MODULES) += module.o sparc_ksyms.o
+obj-y                   += idprom_$(BITS).o
-obj-$(CONFIG_SPARC_LED) += led.o
+obj-y                   += sys_sparc_$(BITS).o
-obj-$(CONFIG_KGDB) += kgdb.o
+obj-$(CONFIG_SPARC32)   += systbls_32.o
+obj-y                   += time_$(BITS).o
+obj-$(CONFIG_SPARC32)   += windows.o
+obj-y                   += cpu_$(BITS).o
+obj-$(CONFIG_SPARC32)   += devices.o
+obj-$(CONFIG_SPARC32)   += tadpole.o
+obj-$(CONFIG_SPARC32)   += tick14.o
+obj-y                   += ptrace_$(BITS).o
+obj-y                   += unaligned_$(BITS).o
+obj-y                   += una_asm_$(BITS).o
+obj-$(CONFIG_SPARC32)   += muldiv.o
+obj-y                   += prom_$(BITS).o
+obj-y                   += of_device_$(BITS).o
+
+# sparc32 do not use GENERIC_HARDIRQS but uses the generic devres implementation
+obj-$(CONFIG_SPARC32)     += devres.o
+devres-y                  := ../../../kernel/irq/devres.o
+
+obj-$(CONFIG_SPARC32)     += dma.o
+
+obj-$(CONFIG_SPARC32_PCI) += pcic.o
+
+obj-$(CONFIG_SMP)         += trampoline_$(BITS).o smp_$(BITS).o
+obj-$(CONFIG_SPARC32_SMP) += sun4m_smp.o sun4d_smp.o
+
+obj-y                     += auxio_$(BITS).o
+obj-$(CONFIG_SUN_PM)      += apc.o pmc.o
+
+obj-$(CONFIG_MODULES)     += module_$(BITS).o
+obj-$(CONFIG_MODULES)     += sparc_ksyms_$(BITS).o
+obj-$(CONFIG_SPARC_LED)   += led.o
+obj-$(CONFIG_KGDB)        += kgdb_$(BITS).o