On 01/17/2013 09:36 AM, Steven J. Hill wrote:
From: "Steven J. Hill" <sjhill@xxxxxxxx>
The BRK_BUG value is used in the BUG and __BUG_ON inline macros. For
standard MIPS cores the code in the 'tne' instruction is 10-bits long.
In microMIPS, the 'tne' instruction is recoded and the code can only be
4-bits long. We use the value of 12 instead of 512 when building a
microMIPS kernel.
Signed-off-by: Steven J. Hill <sjhill@xxxxxxxx>
---
arch/mips/include/asm/break.h | 1 +
arch/mips/include/asm/bug.h | 4 ++++
2 files changed, 5 insertions(+)
diff --git a/arch/mips/include/asm/break.h b/arch/mips/include/asm/break.h
index 9161e68..df9d090 100644
--- a/arch/mips/include/asm/break.h
+++ b/arch/mips/include/asm/break.h
@@ -27,6 +27,7 @@
#define BRK_STACKOVERFLOW 9 /* For Ada stackchecking */
#define BRK_NORLD 10 /* No rld found - not used by Linux/MIPS */
#define _BRK_THREADBP 11 /* For threads, user bp (used by debuggers) */
+#define BRK_BUG_MM 12 /* Used by BUG() in microMIPS mode */
#define BRK_BUG 512 /* Used by BUG() */
Can we move the CONFIG_CPU_MICROMIPS to here and just call the thing
BRK_BUG?
Or perhaps redefining it unconditionally. I am not sure what the
implications of doing that would be.
That way...
#define BRK_KDB 513 /* Used in KDB_ENTER() */
#define BRK_MEMU 514 /* Used by FPU emulator */
diff --git a/arch/mips/include/asm/bug.h b/arch/mips/include/asm/bug.h
index 540c98a..b716fb9 100644
--- a/arch/mips/include/asm/bug.h
+++ b/arch/mips/include/asm/bug.h
@@ -7,6 +7,10 @@
#ifdef CONFIG_BUG
#include <asm/break.h>
+#ifdef CONFIG_CPU_MICROMIPS
+#undef BRK_BUG
+#define BRK_BUG BRK_BUG_MM
+#endif
...We don't need this bit. Doing an #undef risks using different
values for BRK_BUG depending on whether or not asm/bug.h is included.
static inline void __noreturn BUG(void)
{
