From f6b06d9361a008afb93b97fb3683a6e92d69d0f4 Mon Sep 17 00:00:00 2001 From: "Steven J. Hill" Date: Mon, 25 Mar 2013 12:01:00 -0500 Subject: [PATCH] MIPS: microMIPS: Support dynamic ASID sizing. Changes for pure microMIPS cores to dynamically determine the ASID size at boot time. Includes bug fix https://patchwork.linux-mips.org/patch/5230/ Signed-off-by: Steven J. Hill Signed-off-by: Jonas Gorski --- arch/mips/mm/tlbex.c | 34 ++++++++++++++++++++++++++++++++-- 1 file changed, 32 insertions(+), 2 deletions(-) diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c index e2a9e3687c45..fb4ca9984ed1 100644 --- a/arch/mips/mm/tlbex.c +++ b/arch/mips/mm/tlbex.c @@ -309,13 +309,32 @@ static int check_for_high_segbits __cpuinitdata; static void __cpuinit insn_fixup(unsigned int **start, unsigned int **stop, unsigned int i_const) { - unsigned int **p, *ip; + unsigned int **p; for (p = start; p < stop; p++) { +#ifndef CONFIG_CPU_MICROMIPS + unsigned int *ip; + ip = *p; *ip = (*ip & 0xffff0000) | i_const; +#else + unsigned short *ip; + + ip = ((unsigned short *)((unsigned int)*p - 1)); + if ((*ip & 0xf000) == 0x4000) { + *ip &= 0xfff1; + *ip |= (i_const << 1); + } else if ((*ip & 0xf000) == 0x6000) { + *ip &= 0xfff1; + *ip |= ((i_const >> 2) << 1); + } else { + ip++; + *ip = i_const; + } +#endif + local_flush_icache_range((unsigned long)ip, + (unsigned long)ip + sizeof(*ip)); } - local_flush_icache_range((unsigned long)*p, (unsigned long)((*p) + 1)); } #define asid_insn_fixup(section, const) \ @@ -335,6 +354,14 @@ static void __cpuinit setup_asid(unsigned int inc, unsigned int mask, extern asmlinkage void handle_ri_rdhwr_vivt(void); unsigned long *vivt_exc; +#ifdef CONFIG_CPU_MICROMIPS + /* + * Worst case optimised microMIPS addiu instructions support + * only a 3-bit immediate value. + */ + if(inc > 7) + panic("Invalid ASID increment value!"); +#endif asid_insn_fixup(__asid_inc, inc); asid_insn_fixup(__asid_mask, mask); asid_insn_fixup(__asid_version_mask, version_mask); @@ -342,6 +369,9 @@ static void __cpuinit setup_asid(unsigned int inc, unsigned int mask, /* Patch up the 'handle_ri_rdhwr_vivt' handler. */ vivt_exc = (unsigned long *) &handle_ri_rdhwr_vivt; +#ifdef CONFIG_CPU_MICROMIPS + vivt_exc = (unsigned long *)((unsigned long) vivt_exc - 1); +#endif vivt_exc++; *vivt_exc = (*vivt_exc & ~mask) | mask; -- 2.20.1