From 07802d9880eb5cb1a37beaf392439b6f5b80a1d3 Mon Sep 17 00:00:00 2001
From: Thiemo Seufer <ths@networkno.de>
Date: Mon, 19 Feb 2007 17:34:18 +0000
Subject: [PATCH] 	(ColdReset): Set CP0 Config0 to reflect the address
 size supported 	by this simulator. 	(decode_coproc): Recognise
 additional CP0 Config registers 	correctly.

---
 sim/mips/ChangeLog |  8 +++++++
 sim/mips/interp.c  | 57 ++++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 61 insertions(+), 4 deletions(-)

diff --git a/sim/mips/ChangeLog b/sim/mips/ChangeLog
index b6e956eac67..632ae32880f 100644
--- a/sim/mips/ChangeLog
+++ b/sim/mips/ChangeLog
@@ -1,3 +1,11 @@
+2007-02-19  Thiemo Seufer <ths@mips.com>
+            Nigel Stephens  <nigel@mips.com>
+	
+	(ColdReset): Set CP0 Config0 to reflect the address size supported
+	by this simulator.
+	(decode_coproc): Recognise additional CP0 Config registers
+	correctly.
+
 2007-02-19  Thiemo Seufer  <ths@mips.com>
             Nigel Stephens  <nigel@mips.com>
             David Ung  <davidu@mips.com>
diff --git a/sim/mips/interp.c b/sim/mips/interp.c
index 9bef8908c1d..13cd26e2c55 100644
--- a/sim/mips/interp.c
+++ b/sim/mips/interp.c
@@ -1758,6 +1758,20 @@ ColdReset (SIM_DESC sd)
 	    FPR_STATE[rn] = fmt_uninterpreted;
 	}
       
+      /* Initialise the Config0 register. */
+      C0_CONFIG = 0x80000000 		/* Config1 present */
+	| 2;				/* KSEG0 uncached */
+      if (WITH_TARGET_WORD_BITSIZE == 64)
+	{
+	  /* FIXME Currently mips/sim-main.c:address_translation()
+	     truncates all addresses to 32-bits. */
+	  if (0 && WITH_TARGET_ADDRESS_BITSIZE == 64)
+	    C0_CONFIG |= (2 << 13);	/* MIPS64, 64-bit addresses */
+	  else
+	    C0_CONFIG |= (1 << 13);	/* MIPS64, 32-bit addresses */
+	}
+      if (BigEndianMem)
+	C0_CONFIG |= 0x00008000;	/* Big Endian */
     }
 }
 
@@ -2252,10 +2266,11 @@ decode_coproc (SIM_DESC sd,
 #else
 		/* 16 = Config             R4000   VR4100  VR4300 */
               case 16:
-                if (code == 0x00)
-                  GPR[rt] = C0_CONFIG;
-                else
-                  C0_CONFIG = GPR[rt];
+		if (code == 0x00)
+		  GPR[rt] = C0_CONFIG;
+		else
+		  /* only bottom three bits are writable */
+		  C0_CONFIG = (C0_CONFIG & ~0x7) | (GPR[rt] & 0x7);
                 break;
 #endif
 #ifdef SUBTARGET_R3900
@@ -2296,6 +2311,40 @@ decode_coproc (SIM_DESC sd,
 #endif
 	      }
 	  }
+	else if ((code == 0x00 || code == 0x01)
+		 && rd == 16)
+	  {
+	    /* [D]MFC0 RT,C0_CONFIG,SEL */
+	    signed32 cfg = 0;
+	    switch (tail & 0x07) 
+	      {
+	      case 0:
+		cfg = C0_CONFIG;
+		break;
+	      case 1:
+		/* MIPS32 r/o Config1: 
+		   Config2 present */
+		cfg = 0x80000000;
+		/* MIPS16 implemented. 
+		   XXX How to check configuration? */
+		cfg |= 0x0000004;
+		if (CURRENT_FLOATING_POINT == HARD_FLOATING_POINT)
+		  /* MDMX & FPU implemented */
+		  cfg |= 0x00000021;
+		break;
+	      case 2:
+		/* MIPS32 r/o Config2: 
+		   Config3 present. */
+		cfg = 0x80000000;
+		break;
+	      case 3:
+		/* MIPS32 r/o Config3: 
+		   SmartMIPS implemented. */
+		cfg = 0x00000002;
+		break;
+	      }
+	    GPR[rt] = cfg;
+	  }
 	else if (code == 0x10 && (tail & 0x3f) == 0x18)
 	  {
 	    /* ERET */
-- 
2.30.2