MIPS: Make DIEI support as a config option

DI(Disable Interrupt) and EI(Enable Interrupt) instructions is required by
MIPSR2/MIPSR6, however, it appears to be buggy on some processors such as
Loongson-3A1000. Thus we make it as a config option to allow disable it at
compile time with CPU_MIPSR2 selected.

Signed-off-by: Jiaxun Yang <[e-mail]>
Signed-off-by: Paul Burton <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]

arch/mips/Kconfig

···
 	bool
 	default y if CPU_MIPS32_R2 || CPU_MIPS64_R2 || CPU_CAVIUM_OCTEON
 	select CPU_HAS_RIXI
+	select CPU_HAS_DIEI if !CPU_DIEI_BROKEN
 	select MIPS_SPRAM
 
 config CPU_MIPSR6
 	bool
 	default y if CPU_MIPS32_R6 || CPU_MIPS64_R6
 	select CPU_HAS_RIXI
+	select CPU_HAS_DIEI if !CPU_DIEI_BROKEN
 	select HAVE_ARCH_BITREVERSE
 	select MIPS_ASID_BITS_VARIABLE
 	select MIPS_CRC_SUPPORT
···
 	bool
 
 config XKS01
+	bool
+
+config CPU_HAS_DIEI
+	depends on !CPU_DIEI_BROKEN
+	bool
+
+config CPU_DIEI_BROKEN
 	bool
 
 config CPU_HAS_RIXI

arch/mips/include/asm/irqflags.h

···
 #include <asm/compiler.h>
 #include <asm/hazards.h>
 
-#if defined(CONFIG_CPU_MIPSR2) || defined (CONFIG_CPU_MIPSR6)
+#if defined(CONFIG_CPU_HAS_DIEI)
 
 static inline void arch_local_irq_disable(void)
 {
···
 void arch_local_irq_disable(void);
 unsigned long arch_local_irq_save(void);
 void arch_local_irq_restore(unsigned long flags);
-#endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
+#endif /* CONFIG_CPU_HAS_DIEI */
 
 static inline void arch_local_irq_enable(void)
 {
···
 	"	.set	push						\n"
 	"	.set	reorder						\n"
 	"	.set	noat						\n"
-#if   defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
+#if defined(CONFIG_CPU_HAS_DIEI)
 	"	ei							\n"
 #else
 	"	mfc0	$1,$12						\n"

arch/mips/lib/mips-atomic.c

···
 #include <linux/export.h>
 #include <linux/stringify.h>
 
-#if !defined(CONFIG_CPU_MIPSR2) && !defined(CONFIG_CPU_MIPSR6)
+#if !defined(CONFIG_CPU_HAS_DIEI)
 
 /*
  * For cli() we have to insert nops to make sure that the new value
···
 }
 EXPORT_SYMBOL(arch_local_irq_restore);
 
-#endif /* !CONFIG_CPU_MIPSR2 && !CONFIG_CPU_MIPSR6 */
+#endif /* !CONFIG_CPU_HAS_DIEI */