r1525: Add pread/pwrite support on /dev/mem

diff --git a/mtcr.h b/mtcr.h
index fdf6d6986315094c16247dc0f3f796e7125fb1ff..edd6c0fa23c55f51046ccf57c4666bcc7e4a2e5e 100644 (file)
--- a/mtcr.h
+++ b/mtcr.h
@@ -38,6 +38,8 @@
 
 //use memory mapped /dev/mem for access
 #define CONFIG_ENABLE_MMAP 1
+//use pread/pwrite on /dev/mem for access
+#define CONFIG_ENABLE_READWRITE 0
 //use pci configuration cycles for access
 #define CONFIG_ENABLE_PCICONF 1
 
@@ -45,11 +47,11 @@
 #define CONFIG_HAVE_LONG_LONG_ADDRESS 1
 
 
-#if CONFIG_ENABLE_PCICONF
+#if (CONFIG_ENABLE_PCICONF || CONFIG_ENABLE_READWRITE)
 #define _XOPEN_SOURCE 500
 #endif
 
-#if CONFIG_ENABLE_MMAP
+#if (CONFIG_ENABLE_MMAP || CONFIG_ENABLE_READWRITE)
 #define _FILE_OFFSET_BITS 64
 #endif
 
@@ -109,13 +111,12 @@ extern "C" {
 /*  or modified by user programs. */
 typedef struct mfile_t {
     int           fd;
-#if CONFIG_ENABLE_MMAP
     void          *ptr;
-#endif
+    off_t        offset;
 } mfile;
 
 
-#if CONFIG_ENABLE_MMAP
+#if (CONFIG_ENABLE_MMAP || CONFIG_ENABLE_READWRITE)
 /*
  * The PCI interface treats multi-function devices as independent
  * devices.  The slot/function address of each device is encoded
@@ -290,28 +291,37 @@ mfile *mopen(const char *name)
     if (mf->fd<0) goto open_failed;
 
     mf->ptr=NULL;
+    mf->offset=-1;
 #else
     goto open_failed;
 #endif
   }
   else
   {
-#if (CONFIG_ENABLE_MMAP)
+#if (CONFIG_ENABLE_MMAP || CONFIG_ENABLE_READWRITE)
     mf->fd = open("/dev/mem", O_RDWR | O_SYNC);
     if (mf->fd<0) goto open_failed;
 
-    if (mfind(name,&offset)) goto map_failed;
+    if (mfind(name,&offset)) goto find_failed;
+    mf->offset = offset;
 
+#if (CONFIG_ENABLE_MMAP)
     mf->ptr = mmap(NULL, 0x100000, PROT_READ | PROT_WRITE,
         MAP_SHARED, mf->fd, offset);
 
     if ( (! mf->ptr) || (mf->ptr == MAP_FAILED) ) goto map_failed;
+#endif
+
 #else
     goto open_failed;
 #endif
   }
   return mf;
 
+#if (CONFIG_ENABLE_MMAP || CONFIG_ENABLE_READWRITE)
+find_failed:
+#endif
+
 #if (CONFIG_ENABLE_MMAP)
 map_failed:
         err = errno;
@@ -352,6 +362,16 @@ int mread4(mfile *mf, unsigned int offset, u_int32_t *value)
             return 4;
   }
 #endif
+#if CONFIG_ENABLE_READWRITE
+  if (mf->ptr)
+  {
+         u_int32_t v;
+         size_t cnt;
+         cnt = pread(mf->fd, &v, 4, mf->offset + offset);
+         *value = __be32_to_cpu(v);
+          return cnt;
+  }
+#endif
 #if CONFIG_ENABLE_PCICONF
   {
     int rc;
@@ -389,6 +409,16 @@ int mwrite4(mfile *mf, unsigned int offset, u_int32_t value)
             return 4;
   }
 #endif
+#if CONFIG_ENABLE_READWRITE
+  if (mf->ptr)
+  {
+         u_int32_t v;
+         size_t cnt;
+         v = __be32_to_cpu(value);
+         cnt = pwrite(mf->fd, &v, 4, mf->offset + offset); 
+          return cnt;
+  }
+#endif
 #if CONFIG_ENABLE_PCICONF
   {
     int rc;