m68knommu: support version 2 ColdFire split cache

The newer version 2 ColdFire CPU cores support a configurable cache
arrangement. The cache memory can be used as all instruction cache, all
data cache, or split in half for both instruction and data caching.
Support this setup via a Kconfig time menu that allows a kernel builder
to choose the arrangement they want to use.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>

diff --git a/arch/m68k/include/asm/m52xxacr.h b/arch/m68k/include/asm/m52xxacr.h
index 52230b5e1e4dc4407d7df0b73d6c694732bc6fbb..701f680bced9d4e6f8e8a380a714145b3c1aa974 100644 (file)
--- a/arch/m68k/include/asm/m52xxacr.h
+++ b/arch/m68k/include/asm/m52xxacr.h
@@ -53,23 +53,25 @@
 #define ACR_WPROTECT   0x00000004      /* Write protect region */
 
 /*
- * Set the cache controller settings we will use. This code is set to
- * only use the instruction cache, even on the controllers that support
- * split cache. (This setup is trying to preserve the existing behavior
- * for now, in the furture I hope to actually use the split cache mode).
+ * Set the cache controller settings we will use. On the cores that support
+ * a split cache configuration we allow all the combinations at Kconfig
+ * time. For those cores that only have an instruction cache we just set
+ * that as on.
  */
-#if defined(CONFIG_M5206) || defined(CONFIG_M5206e) || \
-    defined(CONFIG_M5249) || defined(CONFIG_M5272)
-#define CACHE_INIT     (CACR_CINV)
-#define CACHE_MODE     (CACR_CENB + CACR_DCM)
+#if defined(CONFIG_CACHE_I)
+#define CACHE_TYPE     CACR_DISD
+#elif defined(CONFIG_CACHE_D)
+#define CACHE_TYPE     CACR_DISI
 #else
-#ifdef CONFIG_COLDFIRE_SW_A7
-#define CACHE_INIT     (CACR_CINV + CACR_DISD)
-#define CACHE_MODE     (CACR_CENB + CACR_DISD + CACR_DCM)
-#else
-#define CACHE_INIT     (CACR_CINV + CACR_DISD + CACR_EUSP)
-#define CACHE_MODE     (CACR_CENB + CACR_DISD + CACR_DCM + CACR_EUSP)
+#define CACHE_TYPE
 #endif
+
+#if defined(CONFIG_HAVE_CACHE_SPLIT)
+#define CACHE_INIT     (CACR_CINV + CACHE_TYPE + CACR_EUSP)
+#define CACHE_MODE     (CACR_CENB + CACHE_TYPE + CACR_DCM + CACR_EUSP)
+#else
+#define CACHE_INIT     (CACR_CINV)
+#define CACHE_MODE     (CACR_CENB + CACR_DCM)
 #endif
 
 #define CACHE_INVALIDATE (CACHE_MODE + CACR_CINV)

diff --git a/arch/m68knommu/Kconfig b/arch/m68knommu/Kconfig
index e6f482d18d05472757af3bf3f0d3a3d9b4d0b70d..61c29081b9981602116a8cb5fb2c63e1c47aa3b5 100644 (file)
--- a/arch/m68knommu/Kconfig
+++ b/arch/m68knommu/Kconfig
@@ -79,6 +79,9 @@ config COLDFIRE_SW_A7
        bool
        default n
 
+config HAVE_CACHE_SPLIT
+       bool
+
 source "init/Kconfig"
 
 source "kernel/Kconfig.freezer"
@@ -124,12 +127,14 @@ config M5206e
 config M520x
        bool "MCF520x"
        select GENERIC_CLOCKEVENTS
+       select HAVE_CACHE_SPLIT
        help
           Freescale Coldfire 5207/5208 processor support.
 
 config M523x
        bool "MCF523x"
        select GENERIC_CLOCKEVENTS
+       select HAVE_CACHE_SPLIT
        help
          Freescale Coldfire 5230/1/2/4/5 processor support
 
@@ -141,6 +146,7 @@ config M5249
 
 config M5271
        bool "MCF5271"
+       select HAVE_CACHE_SPLIT
        help
          Freescale (Motorola) ColdFire 5270/5271 processor support.
 
@@ -152,12 +158,14 @@ config M5272
 
 config M5275
        bool "MCF5275"
+       select HAVE_CACHE_SPLIT
        help
          Freescale (Motorola) ColdFire 5274/5275 processor support.
 
 config M528x
        bool "MCF528x"
        select GENERIC_CLOCKEVENTS
+       select HAVE_CACHE_SPLIT
        help
          Motorola ColdFire 5280/5282 processor support.
 
@@ -250,6 +258,30 @@ config OLDMASK
          Build support for the older revision ColdFire 5307 silicon.
          Specifically this is the 1H55J mask revision.
 
+if HAVE_CACHE_SPLIT
+choice
+       prompt "Split Cache Configuration"
+       default CACHE_I
+
+config CACHE_I
+       bool "Instruction"
+       help
+         Use all of the ColdFire CPU cache memory as an instruction cache.
+
+config CACHE_D
+       bool "Data"
+       help
+         Use all of the ColdFire CPU cache memory as a data cache.
+
+config CACHE_BOTH
+       bool "Both"
+       help
+         Split the ColdFire CPU cache, and use half as an instruction cache
+         and half as a data cache.
+endchoice
+
+endif
+
 comment "Platform"
 
 config PILOT3