Changeset 810 for trunk/softs/giet_tsar/stdio.c

Timestamp:

Sep 19, 2014, 2:53:18 PM (10 years ago)

Author:

cfuguet

Message:

giet_tsar: updating giet_tsar to use new hard_config format

Other optimizations:

• Using a memory lock instead of the hard lock for the TTY
• Each tty channel data is aligned to a cacheline (lock and buffers).
• The applications' ldscript is generated from a template which includes the hard_config.h file.

File:

• trunk/softs/giet_tsar/stdio.c (modified) (10 diffs)

trunk/softs/giet_tsar/stdio.c

@@ -72 +72 @@
 #define in_drivers __attribute__((section (".drivers")))
 #define in_unckdata __attribute__((section (".unckdata")))
+#define cacheline_aligned __attribute__((aligned(64)))
 
 //////////////////////////////////////////////////////////////
@@ -92 +93 @@
 static in_unckdata int volatile  _ioc_status;
 
-static in_unckdata char volatile _tty_get_buf[NB_TTY_CHANNELS];
-static in_unckdata int volatile  _tty_get_full[NB_TTY_CHANNELS] = { [0 ... NB_TTY_CHANNELS-1] = 0 };
+static volatile in_unckdata struct cacheline_aligned {
+    int  lock;
+    int  get_full;
+    char get_buf;
+    char __padding[55];
+} _tty_channel[NB_TTY_CHANNELS];
 
 ////////////////////////////////////////////////////////////////////////////////////////
@@ -141 +146 @@
 in_drivers void  _extended_memcpy( unsigned int dst_cluster,
                                    unsigned int dst_address,
+                                   unsigned int src_cluster,
                                    unsigned int src_address,
                                    unsigned int length )
@@ -157 +163 @@
     for ( i = 0 ; i < length ; i = i+4 )
     {
-        word = _word_extended_read( src_cluster, (src_address + i) );
-        _word_extended_write( dst_cluster, (dst_address + i), word );
+        word = _word_extended_read( src_cluster, src_address + i );
+        _word_extended_write( dst_cluster, dst_address + i, word );
     }
 }
@@ -545 +551 @@
 in_drivers void _tty_get_lock( unsigned int channel )
 {
-    unsigned int base = (unsigned int)&seg_tty_base;
-    unsigned int offset = (TTY_CONFIG + channel*TTY_SPAN) << 2;
-    while ( _word_extended_read( CLUSTER_IO, base + offset ) );
+    register unsigned int* plock = (unsigned int*)&_tty_channel[channel].lock;
+
+    asm volatile (
+            "1:                         \n"
+            "ll     $2,     0(%0)       \n" // $2 <= _tty_lock
+            "bnez   $2,     1b          \n" // retry  if busy
+            "li     $3,     1           \n" // prepare argument for sc
+            "sc     $3,     0(%0)       \n" // try to set _tty_busy
+            "beqz   $3,     1b          \n" // retry if not atomic
+            ::"r"(plock) :"$2","$3");
 }
 
@@ -556 +569 @@
 in_drivers void _tty_release_lock( unsigned int channel )
 {
-    unsigned int base    = (unsigned int)&seg_tty_base;
-    unsigned int offset  = (TTY_CONFIG + channel*TTY_SPAN) << 2;
-    _word_extended_write( CLUSTER_IO, base + offset, 0 );
+    _tty_channel[channel].lock = 0;
 }
 
@@ -813 +824 @@
     unsigned int offset = (index*TTY_SPAN + TTY_READ) << 2;
 
-    _tty_get_buf[index] = _byte_extended_read(CLUSTER_IO, base + offset);
-    _tty_get_full[index] = 1;               // signals character available
+    _tty_channel[index].get_buf  = _byte_extended_read(CLUSTER_IO, base + offset);
+    _tty_channel[index].get_full = 1;               // signals character available
 }
 
@@ -872 +883 @@
 // reset the _ioc_done variable to zero, and releases the _ioc_lock variable.
 ///////////////////////////////////////////////////////////////////////////////////////
-//  If USE_RAMDISK is set, we access a "virtual" block device controler  implemented
+//  If USE_IOC_RDK is set, we access a "virtual" block device controler implemented
 //  as a memory-mapped segment in cluster [0,0] at address seg_ramdisk_base.
 //  The tranfer being fully synchronous, the IOC interrupt is not activated.
@@ -910 +921 @@
     _ioc_get_lock();
 
-    if ( USE_RAMDISK )  // we use an extended_memcpy
+    if ( USE_IOC_RDK )  // we use an extended_memcpy
     {
         unsigned int  src_address = (unsigned int)buffer;
@@ -953 +964 @@
     _ioc_get_lock();
 
-    if ( USE_RAMDISK )  // we use an extended_memcpy
+    if ( USE_IOC_RDK )  // we use an extended_memcpy
     {
         unsigned int  dst_address = (unsigned int)buffer;