Changeset 538 for trunk/hal

Timestamp:

Sep 21, 2018, 10:21:28 PM (6 years ago)

Author:

nicolas.van.phan@…

Message:

TTY MUX 3 : Comment multi_tty TX IRQ enabling

Enabling and disabling IRQs for TX by writing to the CONFIG register
has no effect on the behaviour of the vci_multi_tty regarding interrupts.
N.B. This is not the case for the vci_tty_tsar component.

Moreover, the hal_remote_atomic_cas() triggers a kernel panic for
unknown reasons so far.

File:

• trunk/hal/tsar_mips32/drivers/soclib_mtty.c (modified) (2 diffs)

trunk/hal/tsar_mips32/drivers/soclib_mtty.c

@@ -169 +169 @@
 
                 // enable TX_IRQ
-                xptr_t config_xp = XPTR( tty_cxy , base + MTTY_CONFIG );
-                uint32_t old = hal_remote_lw( config_xp );
-                uint32_t new = old | MTTY_CONFIG_TX_ENABLE;
-                hal_remote_atomic_cas( config_xp , old , new );
+                //      vci_multi_tty devices never raise TX IRQs
+                //      so the following instructions are useless
+                //      and moreover they kernel panic
+                // xptr_t config_xp = XPTR( tty_cxy , base + MTTY_CONFIG );
+                // uint32_t old = hal_remote_lw( config_xp );
+                // uint32_t new = old | MTTY_CONFIG_TX_ENABLE;
+                // hal_remote_atomic_cas( config_xp , old , new );
+                // hal_remote_sw( XPTR( tty_cxy , base + MTTY_CONFIG ) , MTTY_CONFIG_TX_ENABLE );
             }
             else                                // block & deschedule if TX_FIFO full
@@ -495 +499 @@
 
         // disable TX_IRQ 
-        xptr_t config_xp = XPTR( tty_cxy , base + MTTY_CONFIG );
-        uint32_t old = hal_remote_lw( config_xp );
-        uint32_t new = old & ~(MTTY_CONFIG_TX_ENABLE);
-        hal_remote_atomic_cas( config_xp , old , new );
-        //hal_remote_sw( XPTR( tty_cxy , base + MTTY_TX_IRQ_ENABLE ) , 0 );
+        //      vci_multi_tty devices never raise TX IRQs
+        //      so the following instructions are useless
+        //      and moreover they kernel panic
+        // xptr_t config_xp = XPTR( tty_cxy , base + MTTY_CONFIG );
+        // uint32_t old = hal_remote_lw( config_xp );
+        // uint32_t new = old & ~(MTTY_CONFIG_TX_ENABLE);
+        // hal_remote_atomic_cas( config_xp , old , new );
+        // hal_remote_sw( XPTR( tty_cxy , base + MTTY_CONFIG ) , 0 );
 
         // unblock TXT_TX server thread