Initial creation of sourceware repositorygdb-4_18-branchpoint

1 files changed, 361 insertions, 0 deletions

diff --git a/gdb/rdi-share/rx.c b/gdb/rdi-share/rx.c
new file mode 100644
index 0000000..4f434f0
--- /dev/null
+++ b/gdb/rdi-share/rx.c
@@ -0,0 +1,361 @@
+/* 
+ * Copyright (C) 1995 Advanced RISC Machines Limited. All rights reserved.
+ * 
+ * This software may be freely used, copied, modified, and distributed
+ * provided that the above copyright notice is preserved in all copies of the
+ * software.
+ */
+
+/*-*-C-*-
+ *
+ * $Revision$
+ *     $Date$
+ *
+ *
+ *   Project: ANGEL
+ *
+ *     Title:  Character reception engine
+ */
+
+#include <stdarg.h>    /* ANSI varargs support */
+#include "angel.h"     /* Angel system definitions */
+#include "endian.h"    /* Endian independant memory access macros */
+#include "crc.h"       /* crc generation definitions and headers */
+#include "rxtx.h"
+#include "channels.h"
+#include "buffers.h"
+#ifdef TARGET
+#  include "devdriv.h"
+#endif
+#include "logging.h"
+
+static re_status unexp_stx(struct re_state *rxstate);
+static re_status unexp_etx(struct re_state *rxstate);
+
+/* bitfield for the rx_engine state */
+typedef enum rx_state_flag{
+  RST_STX,
+  RST_TYP,
+  RST_LEN,
+  RST_DAT,
+  RST_CRC,
+  RST_ETX,
+  RST_ESC = (0x1 << 0x3)
+} rx_state_flag;
+
+void Angel_RxEngineInit(const struct re_config *rxconfig,
+                        struct re_state *rxstate)
+{
+  rxstate->rx_state = RST_STX;
+  rxstate->field_c = 0;
+  rxstate->index = 0;
+  rxstate->crc = 0;
+  rxstate->error = RE_OKAY;
+  rxstate->config = rxconfig;
+}
+
+re_status Angel_RxEngine(unsigned char new_ch, struct data_packet *packet,
+                         struct re_state *rxstate)
+{
+  /*
+   * TODO: add the flow control bits in
+   * Note: We test for the data field in a seperate case so we can
+   * completely avoid entering the switch for most chars
+   */
+
+  /* see if we're expecting a escaped char */
+  if ((rxstate->rx_state & RST_ESC) == RST_ESC)
+  {
+    /* unescape the char and unset the flag*/
+    new_ch &= ~serial_ESCAPE;
+#ifdef DO_TRACE
+    __rt_trace("rxe-echar-%2x ", new_ch);
+#endif
+    rxstate->rx_state &= ~RST_ESC;
+  }
+  else if ( (1 << new_ch) & rxstate->config->esc_set )
+  {
+    /* see if the incoming char is a special one */
+    if (new_ch == rxstate->config->esc)
+    {
+#ifdef DO_TRACE
+      __rt_trace("rxe-esc ");
+#endif
+      rxstate->rx_state |= RST_ESC;
+      return RS_IN_PKT;
+    }
+    else
+    {
+      /*
+       * must be a normal packet so do some unexpected etx/stx checking
+       * we haven't been told to escape or received an escape so unless
+       * we are expecting an stx or etx then we can take the unexpected 
+       * stx/etx trap
+       */
+      if ((new_ch == (rxstate->config->stx)) && (rxstate->rx_state != RST_STX))
+        return unexp_stx(rxstate);
+      if ((new_ch == (rxstate->config->etx)) && (rxstate->rx_state != RST_ETX))
+        return unexp_etx(rxstate);
+    }
+  }
+
+  if (rxstate->rx_state == RST_DAT)
+  {
+    /*
+     * do this to speed up the common case, no real penalty for
+     * other cases 
+     */
+#ifdef DO_TRACE
+    __rt_trace("rxe-dat ");
+#endif
+
+    rxstate->crc = crc32(&new_ch, 1, rxstate->crc);
+    (packet->data)[rxstate->index++] = (unsigned int)new_ch & 0xff;
+
+    if (rxstate->index == packet->len)
+      rxstate->rx_state = RST_CRC;
+
+    return RS_IN_PKT;
+  }
+
+  /*
+   * Now that the common case is out of the way we can test for everything
+   * else without worrying quite so much about the speed, changing the
+   * order to len,crc,stx,etx,typ might gain a tiny bit of speed but lets
+   * leave that for the moment
+   */
+  switch (rxstate->rx_state)
+  {
+    case RST_STX:
+      if (new_ch == rxstate->config->stx)
+      {
+        rxstate->rx_state = RST_TYP;
+        rxstate->error = RE_OKAY;
+        rxstate->crc = startCRC32;
+        rxstate->index = 0;
+        return RS_IN_PKT;
+      }
+      else
+      {
+        rxstate->error = RE_OKAY;
+        return RS_WAIT_PKT;
+      }
+
+    case RST_TYP:
+      packet->type = (DevChanID)new_ch;
+      rxstate->rx_state = RST_LEN;
+      rxstate->error = RE_OKAY;
+      rxstate->field_c = 0; /* set up here for the length that follows */
+#ifdef DO_TRACE 
+      __rt_trace("rxe-type-%2x ", packet->type);
+#endif
+      rxstate->crc = crc32(&new_ch, 1, rxstate->crc);
+
+      return RS_IN_PKT;
+
+    case RST_LEN:
+      rxstate->crc = crc32(&new_ch, 1, rxstate->crc);
+
+      if (rxstate->field_c++ == 0)
+      {
+        /* first length byte */
+        packet->len = ((unsigned int)new_ch) << 8;
+        return RS_IN_PKT;
+      }
+      else
+      {
+        /* got the whole legth */
+        packet->len |= new_ch;
+#ifdef DO_TRACE
+        __rt_trace("rxe-len-%4x\n", packet->len);
+#endif
+
+        /* check that the length is ok */
+        if (packet->len == 0)
+        {
+          /* empty pkt */
+          rxstate->field_c = 0;
+          rxstate->rx_state = RST_CRC;
+          return RS_IN_PKT;
+        }
+        else
+        {
+          if (packet->data == NULL)
+          {
+            /* need to alloc the data buffer */
+            if (!rxstate->config->ba_callback(
+                packet, rxstate->config->ba_data)) {
+              rxstate->rx_state = RST_STX;
+              rxstate->error = RE_INTERNAL;
+              return RS_BAD_PKT;
+            }
+          }
+
+          if (packet->len > packet->buf_len)
+          {
+            /* pkt bigger than buffer */
+            rxstate->field_c = 0;
+            rxstate->rx_state = RST_STX;
+            rxstate->error = RE_LEN;
+            return RS_BAD_PKT;
+          }
+          else
+          {
+            /* packet ok */
+            rxstate->field_c = 0;
+            rxstate->rx_state = RST_DAT;
+            return RS_IN_PKT;
+          }
+        }
+      }
+
+    case RST_DAT:
+      /* dummy case (dealt with earlier) */
+#ifdef ASSERTIONS_ENABLED
+      __rt_warning("ERROR: hit RST_dat in switch\n");
+#endif
+      rxstate->rx_state = RST_STX;
+      rxstate->error = RE_INTERNAL;
+      return RS_BAD_PKT;
+
+    case RST_CRC:
+      if (rxstate->field_c == 0)
+        packet->crc = 0;
+
+      packet->crc |= (new_ch & 0xFF) << ((3 - rxstate->field_c) * 8);
+      rxstate->field_c++;
+
+      if (rxstate->field_c == 4)
+      {
+        /* last crc field */
+        rxstate->field_c = 0;
+        rxstate->rx_state = RST_ETX;
+#ifdef DO_TRACE
+        __rt_trace("rxe-rcrc-%8x ", packet->crc);
+#endif
+      }
+
+      return RS_IN_PKT;
+
+    case RST_ETX:
+      if (new_ch == rxstate->config->etx)
+      {
+#if defined(DEBUG) && !defined(NO_PKT_DATA)
+        {
+          int c;
+# ifdef DO_TRACE
+          __rt_trace("\n");
+# endif
+          __rt_info("RXE Data =");
+          for (c=0; c < packet->len; c++)
+            __rt_info("%02x", packet->data[c]);
+          __rt_info("\n"); 
+        }
+#endif
+
+        /* check crc */
+        if (rxstate->crc == packet->crc)
+        {
+          /* crc ok */
+          rxstate->rx_state = RST_STX;
+          rxstate->field_c = 0;
+          return RS_GOOD_PKT;
+        }
+        else
+        {
+#ifdef ASSERTIONS_ENABLED
+          __rt_warning("Bad crc, rx calculates it should be 0x%x\n", rxstate->crc);
+#endif
+          rxstate->rx_state = RST_STX;
+          rxstate->error = RE_CRC;
+          return RS_BAD_PKT;
+        }
+      }
+      else if (new_ch == rxstate->config->stx)
+        return unexp_stx(rxstate);
+      else
+      {
+        rxstate->rx_state = RST_STX;
+        rxstate->error = RE_NETX;
+        return RS_BAD_PKT;
+      }
+
+    default:
+#ifdef ASSERTIONS_ENABLED
+      __rt_warning("ERROR fell through rxengine\n");
+#endif
+      rxstate->rx_state = RST_STX;
+      rxstate->error = RE_INTERNAL;
+      return RS_BAD_PKT;
+  }
+}
+
+static re_status unexp_stx(struct re_state *rxstate)
+{
+#ifdef ASSERTIONS_ENABLED
+  __rt_warning("Unexpected stx\n");
+#endif
+  rxstate->crc = startCRC32;
+  rxstate->index = 0;
+  rxstate->rx_state = RST_TYP;
+  rxstate->error = RE_U_STX;
+  rxstate->field_c = 0;
+  return RS_BAD_PKT;
+}
+
+static re_status unexp_etx(struct re_state *rxstate)
+{
+#ifdef ASSERTIONS_ENABLED
+  __rt_warning("Unexpected etx, rxstate: index= 0x%2x, field_c=0x%2x, state=0x%2x\n", rxstate->index, rxstate->field_c, rxstate->rx_state);
+#endif
+  rxstate->crc = 0;
+  rxstate->index = 0;
+  rxstate->rx_state = RST_STX;
+  rxstate->error = RE_U_ETX;
+  rxstate->field_c = 0;
+  return RS_BAD_PKT;
+}
+
+/*
+ * This can be used as the buffer allocation callback for the rx engine,
+ * and makes use of angel_DD_GetBuffer() [in devdrv.h]. 
+ *
+ * Saves duplicating this callback function in every device driver that
+ * uses the rx engine.
+ *
+ * Note that this REQUIRES that the device id is installed as ba_data
+ * in the rx engine config structure for the driver.
+ */
+bool angel_DD_RxEng_BufferAlloc( struct data_packet *packet, void *cb_data )
+{
+#ifdef TARGET
+    DeviceID devid = (DeviceID)cb_data;
+#else
+    IGNORE(cb_data);
+#endif
+
+    if ( packet->type < DC_NUM_CHANNELS )
+    {
+        /* request a buffer down from the channels layer */
+#ifdef TARGET
+        packet->data = angel_DD_GetBuffer( devid, packet->type,
+                                           packet->len              );
+#else
+        packet->data = malloc(packet->len);
+#endif
+        if ( packet->data == NULL )
+           return FALSE;
+        else
+        {
+            packet->buf_len = packet->len;
+            return TRUE;
+        }
+    }
+    else
+    {
+        /* bad type field */
+        return FALSE;
+    }
+}
+
+/* EOF rx.c */