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LEON SPARC V8 processor support for linux-2.6.10

PATCH In review Jiri Gaisler 2 participants 3 messages Jan 4, 2005 – Jan 5, 2005

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Jiri Gaisler

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#0 lore raw

PATCH 1/7 LEON SPARC V8 processor support for linux-2.6.10

linux-2.6.10: Kernel patches:

[1/7] diff2.6.10_include_asm_sparc.diff: diff for include/asm-sparc

include/asm-sparc/amba.h renamed from linux-2.6.10/include/asm-sparc/amba.h +193 -0
diff -Naur ../linux-2.6.10/include/asm-sparc/amba.h linux-2.6.10/include/asm-sparc/amba.h
@@ -0,0 +1,193 @@
+/* 
+ * Copyright (C) 2004 Konrad Eisele ([email protected]), Gaisler Research
+ */
+
+#ifndef _LEON3_AMBA_H__
+#define _LEON3_AMBA_H__
+
+/*
+ *  AMBA Plag & Play Bus Driver Macros
+ *
+ *  Macros used for AMBA Plug & Play bus scanning
+ *
+ *  COPYRIGHT (c) 2004.
+ *  Gaisler Research
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.
+ *
+ */
+
+
+#define LEON3_IO_AREA 0xfff00000
+#define LEON3_CONF_AREA 0xff000
+#define LEON3_AHB_SLAVE_CONF_AREA (1 << 11)
+
+#define LEON3_AHB_CONF_WORDS 8
+#define LEON3_APB_CONF_WORDS 2
+#define LEON3_AHB_MASTERS 8
+#define LEON3_AHB_SLAVES 8
+#define LEON3_APB_SLAVES 16
+#define LEON3_APBUARTS 8
+
+/* Vendor codes */ 
+#define VENDOR_GAISLER   1
+#define VENDOR_PENDER    2
+#define VENDOR_ESA       4 
+#define VENDOR_OPENCORES 8 
+
+/* Gaisler Research device id's */
+#define GAISLER_LEON3    0x003
+#define GAISLER_LEON3DSU 0x004
+#define GAISLER_ETHAHB   0x005
+#define GAISLER_APBMST   0x006
+#define GAISLER_AHBUART  0x007
+#define GAISLER_SRCTRL   0x008
+#define GAISLER_SDCTRL   0x009
+#define GAISLER_APBUART  0x00C
+#define GAISLER_IRQMP    0x00D
+#define GAISLER_AHBRAM   0x00E
+#define GAISLER_GPTIMER  0x011
+#define GAISLER_PCITRG   0x012
+#define GAISLER_PCISBRG  0x013
+#define GAISLER_PCIFBRG  0x014
+#define GAISLER_PCITRACE 0x015
+#define GAISLER_PCIDMA   0x016
+#define GAISLER_AHBTRACE 0x017
+#define GAISLER_ETHDSU   0x018
+   
+#define GAISLER_L2TIME   0xffd /* internal device: leon2 timer */
+#define GAISLER_L2C      0xffe /* internal device: leon2compat */
+#define GAISLER_PLUGPLAY 0xfff /* internal device: plug & play configarea */
+
+
+#ifndef __ASSEMBLER__
+
+extern inline char *gaisler_device_str(int id) {
+  switch(id) {
+  case GAISLER_LEON3:    return "GAISLER_LEON3";
+  case GAISLER_LEON3DSU: return "GAISLER_LEON3DSU";
+  case GAISLER_ETHAHB:   return "GAISLER_ETHAHB";
+  case GAISLER_APBMST:   return "GAISLER_APBMST";
+  case GAISLER_AHBUART:  return "GAISLER_AHBUART";
+  case GAISLER_SRCTRL:   return "GAISLER_SRCTRL";  
+  case GAISLER_SDCTRL:   return "GAISLER_SDCTRL"; 
+  case GAISLER_APBUART:  return "GAISLER_APBUART"; 
+  case GAISLER_IRQMP:    return "GAISLER_IRQMP"; 
+  case GAISLER_AHBRAM:   return "GAISLER_AHBRAM"; 
+  case GAISLER_GPTIMER:  return "GAISLER_GPTIMER";
+  case GAISLER_PCITRG:   return "GAISLER_PCITRG"; 
+  case GAISLER_PCISBRG:  return "GAISLER_PCISBRG"; 
+  case GAISLER_PCIFBRG:  return "GAISLER_PCIFBRG"; 
+  case GAISLER_PCITRACE: return "GAISLER_PCITRACE"; 
+  case GAISLER_AHBTRACE: return "GAISLER_AHBTRACE";
+  case GAISLER_ETHDSU:   return "GAISLER_ETHDSU";
+ 
+  case GAISLER_L2TIME:   return "GAISLER_L2TIME";
+  case GAISLER_L2C:      return "GAISLER_L2C";
+  case GAISLER_PLUGPLAY: return "GAISLER_PLUGPLAY";
+    
+  default: break;
+  }
+  return 0;
+}
+
+#endif
+
+/* European Space Agency device id's */
+#define ESA_LEON2        0x2 
+#define ESA_MCTRL        0xF 
+
+
+#ifndef __ASSEMBLER__
+
+extern inline char *esa_device_str(int id) {
+  switch(id) {
+  case ESA_LEON2:  return "ESA_LEON2";
+  case ESA_MCTRL:  return "ESA_MCTRL";
+  default: break;
+  }
+  return 0;
+}
+
+#endif
+
+/* Opencores device id's */
+#define OPENCORES_PCIBR  0x4  
+#define OPENCORES_ETHMAC 0x5
+
+
+#ifndef __ASSEMBLER__
+
+extern inline char *opencores_device_str(int id) {
+  switch(id) {
+  case OPENCORES_PCIBR:  return "OPENCORES_PCIBR";
+  case OPENCORES_ETHMAC:  return "OPENCORES_ETHMAC";
+  default: break;
+  }
+  return 0;
+}
+
+extern inline char *device_id2str(int vendor, int id) {
+  switch(vendor) {
+  case VENDOR_GAISLER:    return gaisler_device_str(id);
+  case VENDOR_ESA:        return esa_device_str(id);
+  case VENDOR_OPENCORES:  return opencores_device_str(id);
+  case VENDOR_PENDER:
+  default: break;
+  }
+  return 0;
+}
+
+extern inline char *vendor_id2str(int vendor) {
+  switch(vendor) {
+  case VENDOR_GAISLER:    return "VENDOR_GAISLER";
+  case VENDOR_ESA:        return "VENDOR_ESA";
+  case VENDOR_OPENCORES:  return "VENDOR_OPENCORES";
+  case VENDOR_PENDER:     return "VENDOR_PENDER";
+  default: break;
+  }
+  return 0;
+}
+
+#endif
+
+/* Vendor codes */ 
+
+
+
+/* 
+ *
+ * Macros for manipulating Configuration registers  
+ *
+ */
+
+#define LEON3_BYPASS_LOAD_PA(x)	(leon_load_reg ((unsigned long)(x)))
+#define LEON3_BYPASS_STORE_PA(x,v) (leon_store_reg ((unsigned long)(x),(unsigned long)(v)))
+
+#define amba_get_confword(tab, index, word) (LEON3_BYPASS_LOAD_PA((tab).addr[(index)]+(word)))
+
+#define amba_vendor(x) (((x) >> 24) & 0xff)
+
+#define amba_device(x) (((x) >> 12) & 0xfff)
+
+#define amba_ahb_get_membar(tab, index, nr) (LEON3_BYPASS_LOAD_PA((tab).addr[(index)]+4+(nr)))
+
+#define amba_apb_get_membar(tab, index) (LEON3_BYPASS_LOAD_PA((tab).addr[(index)]+1))
+
+#define amba_membar_start(mbar) (((mbar) & 0xfff00000) & (((mbar) & 0xfff0) << 16))
+
+#define amba_iobar_start(base, iobar) ((base) | ((((iobar) & 0xfff00000)>>12) & (((iobar) & 0xfff0)<<4)) )
+
+#define amba_irq(conf) ((conf) & 0xf)
+
+#define amba_membar_type(mbar) ((mbar) & 0xf)
+
+#define AMBA_TYPE_APBIO 0x1
+#define AMBA_TYPE_MEM   0x2
+#define AMBA_TYPE_AHBIO 0x3
+
+#define AMBA_TYPE_AHBIO_ADDR(addr) (LEON3_IO_AREA | ((addr) >> 12))
+#endif
+
include/asm-sparc/asi.h renamed from linux-2.6.10/include/asm-sparc/asi.h +6 -0
diff -Naur ../linux-2.6.10/include/asm-sparc/asi.h linux-2.6.10/include/asm-sparc/asi.h
@@ -108,4 +108,10 @@
 
 #define ASI_M_ACTION       0x4c   /* Breakpoint Action Register (GNU/Viking) */
 
+/* FIXME: non-standard Leon ASI definition */
+#ifdef CONFIG_LEON
+#undef ASI_M_MMUREGS
+#define ASI_M_MMUREGS		0x19
+#endif /* CONFIG_LEON */
+
 #endif /* _SPARC_ASI_H */
include/asm-sparc/leon.h renamed from linux-2.6.10/include/asm-sparc/leon.h +270 -0

270 lines not on this page · raw message

include/asm-sparc/leon3.h renamed from linux-2.6.10/include/asm-sparc/leon3.h +123 -0

123 lines not on this page · raw message

include/asm-sparc/machines.h renamed from linux-2.6.10/include/asm-sparc/machines.h +5 -1
diff -Naur ../linux-2.6.10/include/asm-sparc/machines.h linux-2.6.10/include/asm-sparc/machines.h
@@ -15,7 +15,7 @@
 /* Current number of machines we know about that has an IDPROM
  * machtype entry including one entry for the 0x80 OBP machines.
  */
-#define NUM_SUN_MACHINES   15
+#define NUM_SUN_MACHINES   16
 
 extern struct Sun_Machine_Models Sun_Machines[NUM_SUN_MACHINES];
 

@@ -32,6 +32,7 @@
 
 #define SM_ARCH_MASK  0xf0
 #define SM_SUN4       0x20
+#define  M_LEON2      0x30
 #define SM_SUN4C      0x50
 #define SM_SUN4M      0x70
 #define SM_SUN4M_OBP  0x80

@@ -43,6 +44,9 @@
 #define SM_4_330      0x03    /* Sun 4/300 series */
 #define SM_4_470      0x04    /* Sun 4/400 series */
 
+/* Leon machines */
+#define M_LEON2_SOC   0x01    /* Leon2 SoC */
+
 /* Sun4c machines                Full Name              - PROM NAME */
 #define SM_4C_SS1     0x01    /* Sun4c SparcStation 1   - Sun 4/60  */
 #define SM_4C_IPC     0x02    /* Sun4c SparcStation IPC - Sun 4/40  */
include/asm-sparc/system.h renamed from linux-2.6.10/include/asm-sparc/system.h +1 -0
diff -Naur ../linux-2.6.10/include/asm-sparc/system.h linux-2.6.10/include/asm-sparc/system.h
@@ -29,6 +29,7 @@
   sun4u       = 0x05, /* V8 ploos ploos */
   sun_unknown = 0x06,
   ap1000      = 0x07, /* almost a sun4m */
+  sparc_leon  = 0x08, /* Leon2 SoC */
 };
 
 /* Really, userland should not be looking at any of this... */
include/asm-sparc/vaddrs.h renamed from linux-2.6.10/include/asm-sparc/vaddrs.h +4 -0
diff -Naur ../linux-2.6.10/include/asm-sparc/vaddrs.h linux-2.6.10/include/asm-sparc/vaddrs.h
@@ -17,7 +17,11 @@
 #define SRMMU_NOCACHE_VADDR	(KERNBASE + SRMMU_MAXMEM)
 				/* = 0x0fc000000 */
 /* XXX Empiricals - this needs to go away - KMW */
+#if defined(CONFIG_LEON) || defined(CONFIG_LEON_3)
+#define SRMMU_MIN_NOCACHE_PAGES (128)
+#else
 #define SRMMU_MIN_NOCACHE_PAGES (550)
+#endif
 #define SRMMU_MAX_NOCACHE_PAGES	(1280)
 
 /* The following constant is used in mm/srmmu.c::srmmu_nocache_calcsize()
#1 lore raw

On Maw, 2005-01-04 at 19:03, Jiri Gaisler wrote

Quoted 3 lines
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.

Legalese hat on

Please don't do this. Suppose the file changes or the site goes away. Include a copy of the license in the patch set directly.

author
#2 lore raw

linux-2.6.10: Kernel patches, updated.

[1/7] diff2.6.10_include_asm_sparc.diff: diff for include/asm-sparc

Quoted 14 lines · Alan Cox

On Maw, 2005-01-04 at 19:03, Jiri Gaisler wrote

Quoted 3 lines
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.com/license/LICENSE.

Legalese hat on

Please don't do this. Suppose the file changes or the site goes away. Include a copy of the license in the patch set directly.

.

Signature · 4 lines
--------------------------------------------------------------------------
Gaisler Research, 1:a Långgatan 19, 413 27 Goteborg, Sweden, +46-317758650
fax: +46-31421407 email: [email protected], home page: www.gaisler.com
--------------------------------------------------------------------------
include/asm-sparc/amba.h renamed from linux-2.6.10/include/asm-sparc/amba.h +178 -0
diff -Naur ../linux-2.6.10/include/asm-sparc/amba.h linux-2.6.10/include/asm-sparc/amba.h
@@ -0,0 +1,178 @@
+/* 
+ * Copyright (C) Gaisler Research, 2004 (Konrad Eisele <[email protected]>)
+ */
+
+#ifndef _LEON3_AMBA_H__
+#define _LEON3_AMBA_H__
+
+#define LEON3_IO_AREA 0xfff00000
+#define LEON3_CONF_AREA 0xff000
+#define LEON3_AHB_SLAVE_CONF_AREA (1 << 11)
+
+#define LEON3_AHB_CONF_WORDS 8
+#define LEON3_APB_CONF_WORDS 2
+#define LEON3_AHB_MASTERS 8
+#define LEON3_AHB_SLAVES 8
+#define LEON3_APB_SLAVES 16
+#define LEON3_APBUARTS 8
+
+/* Vendor codes */ 
+#define VENDOR_GAISLER   1
+#define VENDOR_PENDER    2
+#define VENDOR_ESA       4 
+#define VENDOR_OPENCORES 8 
+
+/* Gaisler Research device id's */
+#define GAISLER_LEON3    0x003
+#define GAISLER_LEON3DSU 0x004
+#define GAISLER_ETHAHB   0x005
+#define GAISLER_APBMST   0x006
+#define GAISLER_AHBUART  0x007
+#define GAISLER_SRCTRL   0x008
+#define GAISLER_SDCTRL   0x009
+#define GAISLER_APBUART  0x00C
+#define GAISLER_IRQMP    0x00D
+#define GAISLER_AHBRAM   0x00E
+#define GAISLER_GPTIMER  0x011
+#define GAISLER_PCITRG   0x012
+#define GAISLER_PCISBRG  0x013
+#define GAISLER_PCIFBRG  0x014
+#define GAISLER_PCITRACE 0x015
+#define GAISLER_PCIDMA   0x016
+#define GAISLER_AHBTRACE 0x017
+#define GAISLER_ETHDSU   0x018
+   
+#define GAISLER_L2TIME   0xffd /* internal device: leon2 timer */
+#define GAISLER_L2C      0xffe /* internal device: leon2compat */
+#define GAISLER_PLUGPLAY 0xfff /* internal device: plug & play configarea */
+
+
+#ifndef __ASSEMBLER__
+
+extern inline char *gaisler_device_str(int id) {
+  switch(id) {
+  case GAISLER_LEON3:    return "GAISLER_LEON3";
+  case GAISLER_LEON3DSU: return "GAISLER_LEON3DSU";
+  case GAISLER_ETHAHB:   return "GAISLER_ETHAHB";
+  case GAISLER_APBMST:   return "GAISLER_APBMST";
+  case GAISLER_AHBUART:  return "GAISLER_AHBUART";
+  case GAISLER_SRCTRL:   return "GAISLER_SRCTRL";  
+  case GAISLER_SDCTRL:   return "GAISLER_SDCTRL"; 
+  case GAISLER_APBUART:  return "GAISLER_APBUART"; 
+  case GAISLER_IRQMP:    return "GAISLER_IRQMP"; 
+  case GAISLER_AHBRAM:   return "GAISLER_AHBRAM"; 
+  case GAISLER_GPTIMER:  return "GAISLER_GPTIMER";
+  case GAISLER_PCITRG:   return "GAISLER_PCITRG"; 
+  case GAISLER_PCISBRG:  return "GAISLER_PCISBRG"; 
+  case GAISLER_PCIFBRG:  return "GAISLER_PCIFBRG"; 
+  case GAISLER_PCITRACE: return "GAISLER_PCITRACE"; 
+  case GAISLER_AHBTRACE: return "GAISLER_AHBTRACE";
+  case GAISLER_ETHDSU:   return "GAISLER_ETHDSU";
+ 
+  case GAISLER_L2TIME:   return "GAISLER_L2TIME";
+  case GAISLER_L2C:      return "GAISLER_L2C";
+  case GAISLER_PLUGPLAY: return "GAISLER_PLUGPLAY";
+    
+  default: break;
+  }
+  return 0;
+}
+
+#endif
+
+/* European Space Agency device id's */
+#define ESA_LEON2        0x2 
+#define ESA_MCTRL        0xF 
+
+
+#ifndef __ASSEMBLER__
+
+extern inline char *esa_device_str(int id) {
+  switch(id) {
+  case ESA_LEON2:  return "ESA_LEON2";
+  case ESA_MCTRL:  return "ESA_MCTRL";
+  default: break;
+  }
+  return 0;
+}
+
+#endif
+
+/* Opencores device id's */
+#define OPENCORES_PCIBR  0x4  
+#define OPENCORES_ETHMAC 0x5
+
+
+#ifndef __ASSEMBLER__
+
+extern inline char *opencores_device_str(int id) {
+  switch(id) {
+  case OPENCORES_PCIBR:  return "OPENCORES_PCIBR";
+  case OPENCORES_ETHMAC:  return "OPENCORES_ETHMAC";
+  default: break;
+  }
+  return 0;
+}
+
+extern inline char *device_id2str(int vendor, int id) {
+  switch(vendor) {
+  case VENDOR_GAISLER:    return gaisler_device_str(id);
+  case VENDOR_ESA:        return esa_device_str(id);
+  case VENDOR_OPENCORES:  return opencores_device_str(id);
+  case VENDOR_PENDER:
+  default: break;
+  }
+  return 0;
+}
+
+extern inline char *vendor_id2str(int vendor) {
+  switch(vendor) {
+  case VENDOR_GAISLER:    return "VENDOR_GAISLER";
+  case VENDOR_ESA:        return "VENDOR_ESA";
+  case VENDOR_OPENCORES:  return "VENDOR_OPENCORES";
+  case VENDOR_PENDER:     return "VENDOR_PENDER";
+  default: break;
+  }
+  return 0;
+}
+
+#endif
+
+/* Vendor codes */ 
+
+
+
+/* 
+ *
+ * Macros for manipulating Configuration registers  
+ *
+ */
+
+#define LEON3_BYPASS_LOAD_PA(x)	(leon_load_reg ((unsigned long)(x)))
+#define LEON3_BYPASS_STORE_PA(x,v) (leon_store_reg ((unsigned long)(x),(unsigned long)(v)))
+
+#define amba_get_confword(tab, index, word) (LEON3_BYPASS_LOAD_PA((tab).addr[(index)]+(word)))
+
+#define amba_vendor(x) (((x) >> 24) & 0xff)
+
+#define amba_device(x) (((x) >> 12) & 0xfff)
+
+#define amba_ahb_get_membar(tab, index, nr) (LEON3_BYPASS_LOAD_PA((tab).addr[(index)]+4+(nr)))
+
+#define amba_apb_get_membar(tab, index) (LEON3_BYPASS_LOAD_PA((tab).addr[(index)]+1))
+
+#define amba_membar_start(mbar) (((mbar) & 0xfff00000) & (((mbar) & 0xfff0) << 16))
+
+#define amba_iobar_start(base, iobar) ((base) | ((((iobar) & 0xfff00000)>>12) & (((iobar) & 0xfff0)<<4)) )
+
+#define amba_irq(conf) ((conf) & 0xf)
+
+#define amba_membar_type(mbar) ((mbar) & 0xf)
+
+#define AMBA_TYPE_APBIO 0x1
+#define AMBA_TYPE_MEM   0x2
+#define AMBA_TYPE_AHBIO 0x3
+
+#define AMBA_TYPE_AHBIO_ADDR(addr) (LEON3_IO_AREA | ((addr) >> 12))
+#endif
+
include/asm-sparc/asi.h renamed from linux-2.6.10/include/asm-sparc/asi.h +6 -0
diff -Naur ../linux-2.6.10/include/asm-sparc/asi.h linux-2.6.10/include/asm-sparc/asi.h
@@ -108,4 +108,10 @@
 
 #define ASI_M_ACTION       0x4c   /* Breakpoint Action Register (GNU/Viking) */
 
+/* FIXME: non-standard Leon ASI definition */
+#ifdef CONFIG_LEON
+#undef ASI_M_MMUREGS
+#define ASI_M_MMUREGS		0x19
+#endif /* CONFIG_LEON */
+
 #endif /* _SPARC_ASI_H */
include/asm-sparc/leon.h renamed from linux-2.6.10/include/asm-sparc/leon.h +270 -0

270 lines not on this page · raw message

include/asm-sparc/leon3.h renamed from linux-2.6.10/include/asm-sparc/leon3.h +123 -0

123 lines not on this page · raw message

include/asm-sparc/machines.h renamed from linux-2.6.10/include/asm-sparc/machines.h +5 -1
diff -Naur ../linux-2.6.10/include/asm-sparc/machines.h linux-2.6.10/include/asm-sparc/machines.h
@@ -15,7 +15,7 @@
 /* Current number of machines we know about that has an IDPROM
  * machtype entry including one entry for the 0x80 OBP machines.
  */
-#define NUM_SUN_MACHINES   15
+#define NUM_SUN_MACHINES   16
 
 extern struct Sun_Machine_Models Sun_Machines[NUM_SUN_MACHINES];
 

@@ -32,6 +32,7 @@
 
 #define SM_ARCH_MASK  0xf0
 #define SM_SUN4       0x20
+#define  M_LEON2      0x30
 #define SM_SUN4C      0x50
 #define SM_SUN4M      0x70
 #define SM_SUN4M_OBP  0x80

@@ -43,6 +44,9 @@
 #define SM_4_330      0x03    /* Sun 4/300 series */
 #define SM_4_470      0x04    /* Sun 4/400 series */
 
+/* Leon machines */
+#define M_LEON2_SOC   0x01    /* Leon2 SoC */
+
 /* Sun4c machines                Full Name              - PROM NAME */
 #define SM_4C_SS1     0x01    /* Sun4c SparcStation 1   - Sun 4/60  */
 #define SM_4C_IPC     0x02    /* Sun4c SparcStation IPC - Sun 4/40  */
include/asm-sparc/system.h renamed from linux-2.6.10/include/asm-sparc/system.h +1 -0
diff -Naur ../linux-2.6.10/include/asm-sparc/system.h linux-2.6.10/include/asm-sparc/system.h
@@ -29,6 +29,7 @@
   sun4u       = 0x05, /* V8 ploos ploos */
   sun_unknown = 0x06,
   ap1000      = 0x07, /* almost a sun4m */
+  sparc_leon  = 0x08, /* Leon2 SoC */
 };
 
 /* Really, userland should not be looking at any of this... */
include/asm-sparc/vaddrs.h renamed from linux-2.6.10/include/asm-sparc/vaddrs.h +4 -0
diff -Naur ../linux-2.6.10/include/asm-sparc/vaddrs.h linux-2.6.10/include/asm-sparc/vaddrs.h
@@ -17,7 +17,11 @@
 #define SRMMU_NOCACHE_VADDR	(KERNBASE + SRMMU_MAXMEM)
 				/* = 0x0fc000000 */
 /* XXX Empiricals - this needs to go away - KMW */
+#if defined(CONFIG_LEON) || defined(CONFIG_LEON_3)
+#define SRMMU_MIN_NOCACHE_PAGES (128)
+#else
 #define SRMMU_MIN_NOCACHE_PAGES (550)
+#endif
 #define SRMMU_MAX_NOCACHE_PAGES	(1280)
 
 /* The following constant is used in mm/srmmu.c::srmmu_nocache_calcsize()