Changeset 709 for soft/giet_vm/giet_drivers/tty_driver.c

Timestamp:

Oct 1, 2015, 4:20:46 PM (9 years ago)

Author:

alain

Message:

Major release: Change the task model to implement the POSIX threads API.

• The shell "exec" and "kill" commands can be used to activate/de-activate the applications.
• The "pause", "resume", and "context" commands can be used to stop, restart, a single thtead or to display the thread context.

This version has been tested on the following multi-threaded applications,
that have been modified to use the POSIX threads:

• classif
• convol
• transpose
• gameoflife
• raycast

File:

• soft/giet_vm/giet_drivers/tty_driver.c (modified) (5 diffs)

soft/giet_vm/giet_drivers/tty_driver.c

@@ -19 +19 @@
 
 ////////////////////////////////////////////////////////////////////////////////////
+//               extern variables
+////////////////////////////////////////////////////////////////////////////////////
+
+// This variable is allocated in kernel_init.c file
+extern static_scheduler_t* _schedulers[X_SIZE][Y_SIZE][NB_PROCS_MAX];
+
+////////////////////////////////////////////////////////////////////////////////////
 //               global variables
 ////////////////////////////////////////////////////////////////////////////////////
 
+__attribute__((section(".kdata")))
+tty_fifo_t  _tty_rx_fifo[NB_TTY_CHANNELS];
+
+/*
 __attribute__((section(".kdata")))
 unsigned int   _tty_rx_buf[NB_TTY_CHANNELS];
@@ -27 +38 @@
 __attribute__((section(".kdata")))
 unsigned int   _tty_rx_full[NB_TTY_CHANNELS]; 
+
+__attribute__((section(".kdata")))
+unsigned int   _tty_rx_trdid[NB_TTY_CHANNELS]; 
+*/
 
 ////////////////////////////////////////////////////////////////////////////////////
@@ -52 +67 @@
 void _tty_init( unsigned int channel )
 {
-    _tty_rx_full[channel] = 0;
+    _tty_rx_fifo[channel].sts = 0;
+    _tty_rx_fifo[channel].ptr = 0;
+    _tty_rx_fifo[channel].ptw = 0;
 }
 
@@ -60 +77 @@
                   unsigned int channel )   // TTY channel
 {
-    // transfer character to kernel buffer and acknowledge TTY IRQ
-    _tty_rx_buf[channel]  = _tty_get_register( channel, TTY_READ ); 
+    // get pointer on TTY_RX FIFO
+    tty_fifo_t*   fifo = &_tty_rx_fifo[channel];
 
-    // flush pending memory writes
-    asm volatile( "sync" );
+    // get character from TTY_RX channel and acknowledge IRQ
+    unsigned int data = _tty_get_register( channel, TTY_READ ); 
 
-    // set kernel buffer status
-    _tty_rx_full[channel] = 1;
+    // transfer character to FIFO if not full
+    // discard incoming character if full
+    if ( fifo->sts < TTY_FIFO_DEPTH )
+    {
+        // store data into FIFO 
+        fifo->data[fifo->ptw] = (char)data; 
 
-#if GIET_DEBUG_IRQS  // we don't take the TTY lock to avoid deadlock
-unsigned int gpid           = _get_procid();
-unsigned int cluster_xy     = gpid >> P_WIDTH;
-unsigned int x              = cluster_xy >> Y_WIDTH;
-unsigned int y              = cluster_xy & ((1<<Y_WIDTH)-1);
-unsigned int lpid           = gpid & ((1<<P_WIDTH)-1);
-_puts("\n[IRQS DEBUG] Processor[");
-_putd(x );
-_puts(",");
-_putd(y );
-_puts(",");
-_putd(lpid );
-_puts("] enters _tty_rx_isr() at cycle ");
-_putd(_get_proctime() );
-_puts("\n  read byte = ");
-_putx(_tty_rx_buf[channel] );
-_puts("\n");
-#endif
+        // avoid race 
+        asm volatile( "sync" );
 
+        // update FIFO state
+        fifo->ptw = (fifo->ptw + 1) % TTY_FIFO_DEPTH;
+        fifo->sts = fifo->sts + 1;
+    }
+
+    // get owner thread indexes
+    unsigned int trdid          = fifo->trdid;
+    unsigned int x              = (trdid >> 24) & 0xFF;
+    unsigned int y              = (trdid >> 16) & 0xFF;
+    unsigned int p              = (trdid >>  8) & 0xFF;
+    unsigned int ltid           = (trdid      ) & 0xFF;
+
+    // Reset NORUN_MASK_TTY bit 
+    static_scheduler_t* psched  = (static_scheduler_t*)_schedulers[x][y][p];
+    unsigned int*       ptr     = &psched->context[ltid].slot[CTX_NORUN_ID];
+    _atomic_and( ptr , ~NORUN_MASK_TTY );
 }
 
@@ -95 +116 @@
                   unsigned int channel )   // TTY channel
 {
-    _puts("\n[GIET ERROR] the _tty_tx_isr() is not implemented\n");
+    _printf("\n[GIET ERROR] the _tty_tx_isr() is not implemented\n");
     _exit();
 }