Place FEC buffer descriptors in static RAM. No more cache concerns.

3 files changed, 23 insertions, 30 deletions

diff --git a/c/src/lib/libbsp/m68k/uC5282/ChangeLog b/c/src/lib/libbsp/m68k/uC5282/ChangeLog
index dd4f772b18..2ff8a3e56b 100644
--- a/c/src/lib/libbsp/m68k/uC5282/ChangeLog
+++ b/c/src/lib/libbsp/m68k/uC5282/ChangeLog
@@ -1,3 +1,8 @@
+2005-02-01  Eric Norum <norume@aps.anl.gov>
+
+	* start/start.S, network/network.c: Place FEC buffer descriptors in SRAM.
+	  No longer need to worry about buffer descriptor caching.
+
 2005-01-31  Eric Norum <norume@aps.anl.gov>
 
 	* network/network.c, startup/bspstart.c: Processor doesn't snoop FEC DMA
diff --git a/c/src/lib/libbsp/m68k/uC5282/network/network.c b/c/src/lib/libbsp/m68k/uC5282/network/network.c
index 737670b798..e25f08ca53 100644
--- a/c/src/lib/libbsp/m68k/uC5282/network/network.c
+++ b/c/src/lib/libbsp/m68k/uC5282/network/network.c
@@ -123,19 +123,19 @@ mcf5282_fec_tx_interrupt_handler( rtems_vector_number v )
 }
 
 /*
- * Allocate buffer descriptors
+ * Allocate buffer descriptors from (non-cached) on-chip static RAM
  * Ensure 128-bit (16-byte) alignment
  */
 static mcf5282BufferDescriptor_t *
 mcf5282_bd_allocate(unsigned int count)
 {
-    mcf5282BufferDescriptor_t *p;
+    extern char __SRAMBASE[];
+    static mcf5282BufferDescriptor_t *bdp = (mcf5282BufferDescriptor_t *)__SRAMBASE;
+    mcf5282BufferDescriptor_t *p = bdp;
 
-    p = malloc((count * sizeof(mcf5282BufferDescriptor_t)) + 15, 0, M_NOWAIT);
-    if (!p)
-        rtems_panic("FEC BD");
-    if ((int)p & 0xF)
-        p = (mcf5282BufferDescriptor_t *)((char *)p + (16 - ((int)p & 0xF)));
+    bdp += count;
+    if ((int)bdp & 0xF)
+        bdp = (mcf5282BufferDescriptor_t *)((char *)bdp + (16 - ((int)bdp & 0xF)));
     return p;
 }
 
@@ -302,15 +302,9 @@ static void
 fec_retire_tx_bd(volatile struct mcf5282_enet_struct *sc )
 {
     struct mbuf *m, *n;
-    volatile mcf5282BufferDescriptor_t *txBd;
 
-    for (;;) {
-        if (sc->txBdActiveCount == 0)
-            return;
-        txBd = sc->txBdBase + sc->txBdTail;
-        rtems_cache_invalidate_multiple_data_lines(txBd, sizeof *txBd);
-        if ((txBd->status & MCF5282_FEC_TxBD_R) != 0)
-            return;
+    while ((sc->txBdActiveCount != 0)
+        && ((sc->txBdBase[sc->txBdTail].status & MCF5282_FEC_TxBD_R) == 0)) {
         m = sc->txMbuf[sc->txBdTail];
         MFREE(m, n);
         if (++sc->txBdTail == sc->txBdCount)
@@ -359,9 +353,7 @@ fec_rxDaemon (void *arg)
         /*
          * Wait for packet if there's not one ready
          */
-        rtems_cache_invalidate_multiple_data_lines(rxBd, sizeof *rxBd);
         if ((status = rxBd->status) & MCF5282_FEC_RxBD_E) {
-int chkCount=0 ;
             /*
              * Clear old events.
              */
@@ -373,14 +365,10 @@ int chkCount=0 ;
              * This catches the case when a packet arrives between the
              * `if' above, and the clearing of the RXF bit in the EIR.
              */
-            for (;;) {
+            while ((status = rxBd->status) & MCF5282_FEC_RxBD_E) {
                 rtems_event_set events;
                 int level;
 
-                rtems_cache_invalidate_multiple_data_lines(rxBd, sizeof *rxBd);
-                if (((status = rxBd->status) & MCF5282_FEC_RxBD_E) == 0)
-                    break;
-
                 rtems_interrupt_disable(level);
                 MCF5282_FEC_EIMR |= MCF5282_FEC_EIMR_RXF;
                 rtems_interrupt_enable(level);
@@ -403,7 +391,7 @@ int chkCount=0 ;
             int len = rxBd->length - sizeof(rtems_unsigned32);;
 
             /*
-             * Invalidate the cache and push the packet up
+             * Invalidate the cache and push the packet up.
              * The cache is so small that it's more efficient to just
              * invalidate the whole thing unless the packet is very small.
              */
diff --git a/c/src/lib/libbsp/m68k/uC5282/start/start.S b/c/src/lib/libbsp/m68k/uC5282/start/start.S
index 1adb1fb5eb..bd2b57a582 100644
--- a/c/src/lib/libbsp/m68k/uC5282/start/start.S
+++ b/c/src/lib/libbsp/m68k/uC5282/start/start.S
@@ -313,19 +313,19 @@ SYM(_spuriousInterrupt):
 .align 4
     PUBLIC (start)
 SYM(start):
-    move.w  #0x2700,sr                  | Disable interrupts
-
-    move.l  #__SRAMBASE+1,d0     | Enable the MCF5282 internal SRAM
-    movec   d0,%rambar          | ...so we have a stack
-    move.l  #__SRAMBASE+SRAM_SIZE-4,sp   | Overwrite the fake stack pointer
+    move.w  #0x2700,sr                 | Disable interrupts
 
     /*
      * If we're being started by the debugger, and the debugger has
      * moved the IPSBAR, we're doomed........
      */
-    move.l  #__IPSBAR+1,d0      | Enable the MCF5282 internal peripherals
+    move.l  #__IPSBAR+1,d0             | Enable the MCF5282 internal peripherals
     move.l  d0,DEFAULT_IPSBAR
-    
+    move.l  #__SRAMBASE+0x201,d0       | Enable the MCF5282 internal SRAM
+    movec   d0,%rambar                 | CPU-space copy of RAMBAR
+    move.l  d0,DEFAULT_IPSBAR+8        | Memory-space copy of RAMBAR
+    move.l  #__SRAMBASE+SRAM_SIZE-4,sp | Overwrite the fake stack pointer
+
     /*
      * Copy the vector table to address 0 (VBR must be 0 mod 2^20)
      * Leave the dBUG vectors (0-63) alone