From 7d53e9c4cd21cbc82b7422c90852e56baaf7ddae Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Thu, 9 Jul 2015 10:40:42 +0100 Subject: [PATCH] MIPS: CM3: Add support for CM3 L2 cache. Detect the L2 cache configuration from GCR_L2_CONFIG when a CM3 is present in the system, rather than from Config2 which does not expose the L2 configuration on I6400. Signed-off-by: Paul Burton Signed-off-by: Markos Chandras Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10641/ Signed-off-by: Ralf Baechle --- arch/mips/mm/sc-mips.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/arch/mips/mm/sc-mips.c b/arch/mips/mm/sc-mips.c index 4ceafd13870c..5fa452e8cff9 100644 --- a/arch/mips/mm/sc-mips.c +++ b/arch/mips/mm/sc-mips.c @@ -14,6 +14,7 @@ #include #include #include +#include /* * MIPS32/MIPS64 L2 cache handling @@ -94,6 +95,34 @@ static inline int mips_sc_is_activated(struct cpuinfo_mips *c) return 1; } +static int __init mips_sc_probe_cm3(void) +{ + struct cpuinfo_mips *c = ¤t_cpu_data; + unsigned long cfg = read_gcr_l2_config(); + unsigned long sets, line_sz, assoc; + + if (cfg & CM_GCR_L2_CONFIG_BYPASS_MSK) + return 0; + + sets = cfg & CM_GCR_L2_CONFIG_SET_SIZE_MSK; + sets >>= CM_GCR_L2_CONFIG_SET_SIZE_SHF; + c->scache.sets = 64 << sets; + + line_sz = cfg & CM_GCR_L2_CONFIG_LINE_SIZE_MSK; + line_sz >>= CM_GCR_L2_CONFIG_LINE_SIZE_SHF; + c->scache.linesz = 2 << line_sz; + + assoc = cfg & CM_GCR_L2_CONFIG_ASSOC_MSK; + assoc >>= CM_GCR_L2_CONFIG_ASSOC_SHF; + c->scache.ways = assoc + 1; + c->scache.waysize = c->scache.sets * c->scache.linesz; + c->scache.waybit = __ffs(c->scache.waysize); + + c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT; + + return 1; +} + static inline int __init mips_sc_probe(void) { struct cpuinfo_mips *c = ¤t_cpu_data; @@ -103,6 +132,9 @@ static inline int __init mips_sc_probe(void) /* Mark as not present until probe completed */ c->scache.flags |= MIPS_CACHE_NOT_PRESENT; + if (mips_cm_revision() >= CM_REV_CM3) + return mips_sc_probe_cm3(); + /* Ignore anything but MIPSxx processors */ if (!(c->isa_level & (MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M32R2 | MIPS_CPU_ISA_M32R6 | MIPS_CPU_ISA_M64R1 |