Changeset e0cd9042 in mainline

Timestamp:

2012-08-13T22:55:25Z (12 years ago)

Author:

Martin Sucha <sucha14@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

188c76c

Parents:

58a369e

Message:

ns8250: Report buffer overrun errors

File:

• uspace/drv/char/ns8250/ns8250.c (modified) (5 diffs)

uspace/drv/char/ns8250/ns8250.c

@@ -82 +82 @@
 /** Interrupt ID Register definition. */
 #define NS8250_IID_ACTIVE       (1 << 0)
+#define NS8250_IID_CAUSE_MASK 0x0e
+#define NS8250_IID_CAUSE_RXSTATUS 0x06
 
 /** FIFO Control Register definition. */
@@ -466 +468 @@
 {
         /* Interrupt when data received. */
-        pio_write_8(&regs->ier, NS8250_IER_RXREADY);
+        pio_write_8(&regs->ier, NS8250_IER_RXREADY | NS8250_IER_RXSTATUS);
         pio_write_8(&regs->mcr, NS8250_MCR_DTR | NS8250_MCR_RTS 
             | NS8250_MCR_OUT2);
@@ -504 +506 @@
         async_msg_1(exch, IRC_ENABLE_INTERRUPT, ns->irq);
         async_exchange_end(exch);
+
+        /* Read LSR to clear possible previous LSR interrupt */
+        pio_read_8(&ns->regs->lsr);
 
         /* Enable interrupt on the serial port. */
@@ -766 +771 @@
 /** The interrupt handler.
  *
- * The serial port is initialized to interrupt when some data come, so the
- * interrupt is handled by reading the incomming data.
+ * The serial port is initialized to interrupt when some data come or line
+ * status register changes, so the interrupt is handled by reading the incoming
+ * data and reading the line status register.
  *
  * @param dev           The serial port device.
@@ -774 +780 @@
     ipc_call_t *icall)
 {
-        ns8250_read_from_device(NS8250_FROM_DEV(dev));
+        ns8250_t *ns = NS8250_FROM_DEV(dev);
+
+        uint8_t iir = pio_read_8(&ns->regs->iid);
+        if ((iir & NS8250_IID_CAUSE_MASK) == NS8250_IID_CAUSE_RXSTATUS) {
+                uint8_t lsr = pio_read_8(&ns->regs->lsr);
+                if (lsr & NS8250_LSR_OE) {
+                        ddf_msg(LVL_WARN, "Overrun error on %s", ns->dev->name);
+                }
+        }
+        
+        ns8250_read_from_device(ns);
 }