From: "Steven J. Hill" <Steven.Hill@xxxxxxxxxx>
MIPS32R3 introduced a new set of Segmentation Control registers which
increase the flexibility of the segmented-based memory scheme.
Signed-off-by: Steven J. Hill <Steven.Hill@xxxxxxxxxx>
Signed-off-by: Markos Chandras <markos.chandras@xxxxxxxxxx>
---
arch/mips/include/asm/cpu-features.h | 4 ++++
arch/mips/include/asm/cpu.h | 1 +
arch/mips/include/asm/mipsregs.h | 29 +++++++++++++++++++++++++++++
arch/mips/kernel/cpu-probe.c | 2 ++
4 files changed, 36 insertions(+)
diff --git a/arch/mips/include/asm/cpu-features.h b/arch/mips/include/asm/cpu-features.h
index 296606b..6e70b03 100644
--- a/arch/mips/include/asm/cpu-features.h
+++ b/arch/mips/include/asm/cpu-features.h
@@ -23,6 +23,10 @@
#ifndef cpu_has_tlbinv
#define cpu_has_tlbinv (cpu_data[0].options & MIPS_CPU_TLBINV)
#endif
+#ifndef cpu_has_segments
+#define cpu_has_segments (cpu_data[0].options & MIPS_CPU_SEGMENTS)
+#endif
+
/*
* For the moment we don't consider R6000 and R8000 so we can assume that
diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h
index fd3bc43..7974be9 100644
--- a/arch/mips/include/asm/cpu.h
+++ b/arch/mips/include/asm/cpu.h
@@ -349,6 +349,7 @@ enum cpu_type_enum {
#define MIPS_CPU_RIXI 0x00800000 /* CPU has TLB Read/eXec Inhibit */
#define MIPS_CPU_MICROMIPS 0x01000000 /* CPU has microMIPS capability */
#define MIPS_CPU_TLBINV 0x02000000 /* CPU supports TLBINV/F */
+#define MIPS_CPU_SEGMENTS 0x04000000 /* CPU supports Segmentation Control registers */
/*
* CPU ASE encodings
diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h
index 412fe99..0558f9b 100644
--- a/arch/mips/include/asm/mipsregs.h
+++ b/arch/mips/include/asm/mipsregs.h
@@ -664,6 +664,26 @@
#define MIPS_FPIR_L (_ULCAST_(1) << 21)
#define MIPS_FPIR_F64 (_ULCAST_(1) << 22)
+/*
+ * Bits in the MIPS32 Memory Segmentation registers.
+ */
+#define MIPS_SEGCFG_PA_SHIFT 9
+#define MIPS_SEGCFG_PA (_ULCAST_(127) << MIPS_SEGCFG_PA_SHIFT)
+#define MIPS_SEGCFG_AM_SHIFT 4
+#define MIPS_SEGCFG_AM (_ULCAST_(7) << MIPS_SEGCFG_AM_SHIFT)
+#define MIPS_SEGCFG_EU_SHIFT 3
+#define MIPS_SEGCFG_EU (_ULCAST_(1) << MIPS_SEGCFG_EU_SHIFT)
+#define MIPS_SEGCFG_C_SHIFT 0
+#define MIPS_SEGCFG_C (_ULCAST_(7) << MIPS_SEGCFG_C_SHIFT)
+
+#define MIPS_SEGCFG_UUSK _ULCAST_(7)
+#define MIPS_SEGCFG_USK _ULCAST_(5)
+#define MIPS_SEGCFG_MUSUK _ULCAST_(4)
+#define MIPS_SEGCFG_MUSK _ULCAST_(3)
+#define MIPS_SEGCFG_MSK _ULCAST_(2)
+#define MIPS_SEGCFG_MK _ULCAST_(1)
+#define MIPS_SEGCFG_UK _ULCAST_(0)
+
#ifndef __ASSEMBLY__
/*
@@ -1138,6 +1158,15 @@ do { \
#define read_c0_ebase() __read_32bit_c0_register($15, 1)
#define write_c0_ebase(val) __write_32bit_c0_register($15, 1, val)
+/* MIPSR3 */
+#define read_c0_segctl0() __read_32bit_c0_register($5, 2)
+#define write_c0_segctl0(val) __write_32bit_c0_register($5, 2, val)
+
+#define read_c0_segctl1() __read_32bit_c0_register($5, 3)
+#define write_c0_segctl1(val) __write_32bit_c0_register($5, 3, val)
+
+#define read_c0_segctl2() __read_32bit_c0_register($5, 4)
+#define write_c0_segctl2(val) __write_32bit_c0_register($5, 4, val)
/* Cavium OCTEON (cnMIPS) */
#define read_c0_cvmcount() __read_ulong_c0_register($9, 6)
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 5dac95a..b534d33 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -272,6 +272,8 @@ static inline unsigned int decode_config3(struct cpuinfo_mips *c)
c->options |= MIPS_CPU_MICROMIPS;
if (config3 & MIPS_CONF3_VZ)
c->ases |= MIPS_ASE_VZ;
+ if (config3 & MIPS_CONF3_SC)
+ c->options |= MIPS_CPU_SEGMENTS;
return config3 & MIPS_CONF_M;
}
--
1.8.4.3
