From 41c594ab65fc89573af296d192aa5235d09717ab Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Wed, 5 Apr 2006 09:45:45 +0100 Subject: [MIPS] MT: Improved multithreading support. Signed-off-by: Ralf Baechle --- arch/mips/kernel/genex.S | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'arch/mips/kernel/genex.S') diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S index 04418b6568b0..ff7af369f286 100644 --- a/arch/mips/kernel/genex.S +++ b/arch/mips/kernel/genex.S @@ -12,6 +12,7 @@ #include #include +#include #include #include #include @@ -171,6 +172,15 @@ NESTED(except_vec_vi, 0, sp) SAVE_AT .set push .set noreorder +#ifdef CONFIG_MIPS_MT_SMTC + /* + * To keep from blindly blocking *all* interrupts + * during service by SMTC kernel, we also want to + * pass the IM value to be cleared. + */ +EXPORT(except_vec_vi_mori) + ori a0, $0, 0 +#endif /* CONFIG_MIPS_MT_SMTC */ EXPORT(except_vec_vi_lui) lui v0, 0 /* Patched */ j except_vec_vi_handler @@ -187,6 +197,25 @@ EXPORT(except_vec_vi_end) NESTED(except_vec_vi_handler, 0, sp) SAVE_TEMP SAVE_STATIC +#ifdef CONFIG_MIPS_MT_SMTC + /* + * SMTC has an interesting problem that interrupts are level-triggered, + * and the CLI macro will clear EXL, potentially causing a duplicate + * interrupt service invocation. So we need to clear the associated + * IM bit of Status prior to doing CLI, and restore it after the + * service routine has been invoked - we must assume that the + * service routine will have cleared the state, and any active + * level represents a new or otherwised unserviced event... + */ + mfc0 t1, CP0_STATUS + and t0, a0, t1 + mfc0 t2, CP0_TCCONTEXT + or t0, t0, t2 + mtc0 t0, CP0_TCCONTEXT + xor t1, t1, t0 + mtc0 t1, CP0_STATUS + ehb +#endif /* CONFIG_MIPS_MT_SMTC */ CLI move a0, sp jalr v0 -- cgit v1.2.1