8051 is getting closer. Still have to setup timer and uart.

git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@32 7fd9a85b-ad96-42d3-883c-3090e2eb8679

nuttx/Documentation/NuttX.html

@@ -33,10 +33,10 @@
 <li><b>8051 Microcontroller</b>.
     This port uses the <a href="http://www.pjrc.com/">PJRC</a> 87C52 development system
     and the <a href="http://sdcc.sourceforge.net/">SDCC</a> toolchain.
-    This port will require a few more weeks before it is ready for time prime.</li>
+    This port will require a few more weeks before it is ready for prime time.</li>
 <li><b>Motorola (Freescale) MC68HC908GP32 Microcontroller</b>.
     Using the Axiom CMS8GP32 development board.
-    This is next in the queue.</li?
+    This is next in the queue.</li>
 <li><b>Other ports</b>.
     I also have partial ports for the TI TMS320DM270 and for MIPS. 
 </ul>

nuttx/arch/README.txt

@@ -1,5 +1,15 @@
 Architecture-Specific Code
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
+Table of Contents
+^^^^^^^^^^^^^^^^^
+
+  o Architecture-Specific Code
+  o Summary of Files
+  o Supported Architectures
+  o Configuring NuttX
+
+Architecture-Specific Code
+^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 The file include/nuttx/arch.h identifies all of the APIs that must
 be provided by the architecture specific logic.  (It also includes
@@ -192,6 +202,30 @@ src/Makefile
   the final link with libup.a and other system archives to generate the
   final executable.
 
+Supported Architectures
+^^^^^^^^^^^^^^^^^^^^^^^
+
+arch/c5471
+    TI TMS320C5471 (also called TMS320DM180).
+    NuttX operates on the ARM7 of this dual core processor. This port
+    uses the Spectrum Digital evaluation board with a GNU arm-elf toolchain*.
+    This port is in progress and partially functional (However, my board
+    is dead at the moment so it will be awhile before I fix it).
+
+arch/pjrc-8051
+    8051 Microcontroller.  This port uses the PJRC 87C52 development system
+    and the SDCC toolchain.   This port is not quite ready for prime time.
+
+arch/axiom-mc68
+    For the Motorola (Freescale) MC68HC908GP32 Microcontroller using the
+    Axiom CMS8GP32 development board. This has not yet been checked-in.
+
+arch/sim
+  x86 Linux Simulation</b>.  Fully functional.
+
+Other ports for the for the TI TMS320DM270 and for MIPS are in various states
+of progress
+
 Configuring NuttX
 ^^^^^^^^^^^^^^^^^
 

nuttx/arch/c5471/src/up_irq.c

@@ -147,7 +147,7 @@ static inline void up_vectorinitialize(void)
  ************************************************************/
 
 /************************************************************
- * Name: irq_initialize
+ * Name: up_irqinitialize
  ************************************************************/
 
 void up_irqinitialize(void)

nuttx/arch/pjrc-8051/src/Makefile

@@ -47,7 +47,8 @@ CSRCS		= up_initialize.c up_idle.c up_interruptcontext.c \
 		  up_initialstate.c up_unblocktask.c up_blocktask.c \
 		  up_releasepending.c up_reprioritizertr.c \
 		  up_exit.c up_assert.c up_allocateheap.c \
-		  up_irq.c up_savecontext.c up_restorecontext.c up_putc.c
+		  up_irq.c up_savecontext.c up_restorecontext.c \
+		  up_timerisr.c up_putc.c
 COBJS		= $(CSRCS:.c=$(OBJEXT))
 SRCS		= $(SSRCS) $(CSRCS)
 OBJS		= $(AOBJS) $(COBJS)

nuttx/arch/pjrc-8051/src/up_blocktask.c

@@ -125,27 +125,24 @@ void up_block_task(FAR _TCB *tcb, tstate_t task_state)
         {
           /* Are we in an interrupt handler? */
 
-          if (g_ininterrupt)
+          if (g_irqtos)
             {
-#if 0
-# warning REVISIT
               /* Yes, then we have to do things differently.
                * Just copy the current registers into the OLD rtcb.
                */
 
-               up_copystate(&tcb->xcp, current_regs);
+               up_savestack(&tcb->xcp);
 
               /* Restore the exception context of the rtcb at the (new) head 
                * of the g_readytorun task list.
                */
 
-              rtcb = (_TCB*)g_readytorun.head;
+              rtcb = (FAR _TCB*)g_readytorun.head;
               dbg("New Active Task TCB=%p\n", rtcb);
 
               /* Then switch contexts */
 
-              up_copystate(current_regs, &tcb->xcp);
+              up_restorestack(&tcb->xcp);
-#endif
             }
 
           /* Copy the user C context into the TCB at the (old) head of the

nuttx/arch/pjrc-8051/src/up_head.S

@@ -54,7 +54,7 @@
  * Public Data
  ************************************************************/
 
-	.globl	_g_ininterrupt
+	.globl	_g_irqtos
 
 /************************************************************
  * Public Functions
@@ -174,6 +174,11 @@ _up_interrupt:
 	clr	psw
 	push	_bp
 
+	/* Mark that we are in an interrupt */
+
+	mov	dptr, #_g_irqtos
+        movx    @dptr, a
+
 	/* Now call void irq_dispatch(int irq, FAR void *context)
          *
 	 * First, create the first argument as (int)irqno
@@ -184,18 +189,31 @@ _up_interrupt:
 
         /* Create the second argument (void *context) on the stack */
 
-        push    sp
+	push	sp
-        clr     a
+	clr	a
-        push    acc
+	push	acc
 
-	/* Then dispatch the IRQ */
+	/* Then dispatch the IRQ.  On return, the stack is off by
+	 * by two because the above two pushes, but we fix that by
+	 * reloading sp from g_irqtos below.
+	 */
 
 	lcall	_irq_dispatch
 
-	/* Clean up the stack */
+	/* Get the stackpointer.  This might be the stack pointer that
+	 * we increment above or it might be the stack pointer of a
+	 * new task if the a context switch happened during the
+	 * interrupt handling.
+	 */
 
-        dec     sp
+	mov	dptr, #_g_irqtos
-        dec     sp
+	movx	a, @dptr
+	mov	sp, a
+
+	/* Indicate that we are no longer in an interrupt */
+
+	clr	a
+	movx	@dptr, a
 
 	/* Then return from the interrupt */
 

nuttx/arch/pjrc-8051/src/up_initialize.c

@@ -51,9 +51,13 @@
  * Private Data
  ************************************************************/
 
-/* TRUE if processing an interrupt */
+/* This is the top of the stack containing the interrupt stack frame.  It
+ * is set when processing an interrupt.  It is also cleared when the
+ * interrupt returns so this can also be used like a boolean indication that
+ * we are in an interrupt.
+ */
 
-boolean g_ininterrupt;
+ubyte g_irqtos;
 
 /************************************************************
  * Private Functions
@@ -87,12 +91,16 @@ void up_initialize(void)
 {
  /* Initialize global variables */
 
-  g_ininterrupt = FALSE;
+  g_irqtos = 0;
 
   /* Initialize the interrupt subsystem */
 
+  up_irqinitialize();
+
   /* Initialize the system timer interrupt */
 
+  up_timerinit();
+
   /* Initialize the serial console support */
 }
 

nuttx/arch/pjrc-8051/src/up_internal.h

@@ -106,9 +106,13 @@
 
 #ifndef __ASSEMBLY__
 
-/* TRUE if processing an interrupt */
+/* This is the top of the stack containing the interrupt stack frame.  It
+ * is set when processing an interrupt.  It is also cleared when the
+ * interrupt returns so this can also be used like a boolean indication that
+ * we are in an interrupt.
+ */
 
-extern boolean g_ininterrupt;
+extern ubyte g_irqtos;
 
 #endif /* __ASSEMBLY */
 
@@ -118,8 +122,12 @@ extern boolean g_ininterrupt;
 
 #ifndef __ASSEMBLY__
 
-extern ubyte up_savecontext(FAR struct xcptcontext *context);
+extern void  up_irqinitialize(void);
 extern void  up_restorecontext(FAR struct xcptcontext *context);
+extern void up_restorestack(FAR struct xcptcontext *context);
+extern ubyte up_savecontext(FAR struct xcptcontext *context);
+extern void  up_savestack(FAR struct xcptcontext *context);
+extern void  up_timerinit(void);
 
 #endif /* __ASSEMBLY */
 #endif /* __ARCH_UP_INTERNAL_H */

nuttx/arch/pjrc-8051/src/up_interruptcontext.c

@@ -64,5 +64,5 @@
 
 boolean up_interrupt_context(void)
 {
-   return g_ininterrupt;
+   return g_irqtos != 0;
 }

nuttx/arch/pjrc-8051/src/up_irq.c

@@ -154,4 +154,4 @@ void up_enable_irq(int irq)
     {
       _up_enable_irq(~(1 << irq));
     }
-}
+}

nuttx/arch/pjrc-8051/src/up_releasepending.c

@@ -88,27 +88,24 @@ void up_release_pending(void)
        * interrupt context:
        */
 
-      if (g_ininterrupt)
+      if (g_irqtos)
         {
-#if 0
-# warning REVISIT
           /* Yes, then we have to do things differently.
            * Just copy the current registers into the OLD rtcb.
            */
 
-           up_copystate(&tcb->xcp, current_regs);
+           up_savestack(&rtcb->xcp);
 
           /* Restore the exception context of the rtcb at the (new) head 
            * of the g_readytorun task list.
            */
 
-          rtcb = (_TCB*)g_readytorun.head;
+          rtcb = (FAR _TCB*)g_readytorun.head;
           dbg("New Active Task TCB=%p\n", rtcb);
 
           /* Then switch contexts */
 
-          up_copystate(current_regs, &tcb->xcp);
+          up_restorestack(&rtcb->xcp);
-#endif
         }
 
       /* Copy the exception context into the TCB of the task that

nuttx/arch/pjrc-8051/src/up_reprioritizertr.c

@@ -136,28 +136,26 @@ void up_reprioritize_rtr(FAR _TCB *tcb, ubyte priority)
 
          /* Are we in an interrupt handler? */
 
-          if (g_ininterrupt)
+          if (g_irqtos)
             {
-#if 0
-# warning REVISIT
               /* Yes, then we have to do things differently.
                * Just copy the current registers into the OLD rtcb.
                */
 
-               up_copystate(&tcb->xcp, current_regs);
+               up_savestack(&tcb->xcp);
 
               /* Restore the exception context of the rtcb at the (new) head 
                * of the g_readytorun task list.
                */
 
-              rtcb = (_TCB*)g_readytorun.head;
+              rtcb = (FAR _TCB*)g_readytorun.head;
               dbg("New Active Task TCB=%p\n", rtcb);
 
               /* Then switch contexts */
 
-              up_copystate(current_regs, &tcb->xcp);
+              up_restorestack(&tcb->xcp);
-#endif
             }
+
           /* Copy the exception context into the TCB at the (old) head of the
            * g_readytorun Task list. if up_savecontext returns a non-zero
            * value, then this is really the previously running task restarting!

nuttx/arch/pjrc-8051/src/up_restorecontext.c

@@ -134,8 +134,8 @@ static void up_popcontext(ubyte newsp) __naked
 
 void up_restorecontext(FAR struct xcptcontext *context)
 {
-  int nbytes = context->nbytes;
+  int nbytes      = context->nbytes;
-  FAR ubyte *src = context->stack;
+  FAR ubyte *src  = context->stack;
   FAR ubyte *dest = (FAR ubyte*)STACK_BASE;
 
   /* Interrupts should be disabled for the following.  up_popcontext() will
@@ -149,8 +149,50 @@ void up_restorecontext(FAR struct xcptcontext *context)
       *src++ = *dest++;
     }
 
-  /* Then return to the restored context */
+  /* Then return to the restored context (probably restoring interrupts) */
 
   up_popcontext(context->nbytes + (STACK_BASE-1));
 }
 
+/**************************************************************************
+ * Name: up_restorestack
+ *
+ * Description:
+ *   Restore the entire interrupt stack contents in the provided context
+ *   structure.
+ *
+ * Inputs:
+ *   context - the context structure from  which to restore the stack info
+ *
+ * Return:
+ *   None
+ *
+ * Assumptions:
+ *   - We are in an interrupt handler with g_irqtos set
+ *   - Interrupts are disabled
+ *
+ **************************************************************************/
+
+void up_restorestack(FAR struct xcptcontext *context)
+{
+  /* Now copy the current stack frame (including the saved execution
+   * context) from internal RAM to XRAM.
+   */
+
+  ubyte nbytes     = context->nbytes;
+  FAR ubyte *src   = context->stack;
+  FAR ubyte *dest  = (FAR ubyte*)STACK_BASE;
+
+  while (nbytes--)
+    {
+      *dest++ = *src++;
+    }
+
+  /* We are still in the interrupt context, but the size of the interrupt
+   * stack has changed.
+   */
+
+  g_irqtos = context->nbytes + (STACK_BASE-1);
+}
+
+

nuttx/arch/pjrc-8051/src/up_savecontext.c

@@ -126,7 +126,7 @@ static ubyte up_pushcontext(void) __naked
  * Inputs:
  *   context - the context structure in which to save the stack info
  *
- * Return
+ * Return:
  *   0 = Normal state save return
  *   1 = This is the matching return from up_restorecontext()
  *
@@ -165,3 +165,39 @@ ubyte up_savecontext(FAR struct xcptcontext *context)
   irqrestore(flags);
   return 1;
 }
+
+/**************************************************************************
+ * Name: up_savestack
+ *
+ * Description:
+ *   Save the entire interrupt stack contents in the provided context
+ *   structure.
+ *
+ * Inputs:
+ *   context - the context structure in which to save the stack info
+ *
+ * Return:
+ *   None
+ *
+ * Assumptions:
+ *   - We are in an interrupt handler with g_irqtos set
+ *   - Interrupts are disabled
+ *
+ **************************************************************************/
+
+void up_savestack(FAR struct xcptcontext *context)
+{
+  /* Now copy the current stack frame (including the saved execution
+   * context) from internal RAM to XRAM.
+   */
+
+  ubyte nbytes    = g_irqtos - (STACK_BASE-1);
+  FAR ubyte *src  = (FAR ubyte*)STACK_BASE;
+  FAR ubyte *dest = context->stack;
+
+  context->nbytes = nbytes;
+  while (nbytes--)
+    {
+      *dest++ = *src++;
+    }
+}

nuttx/arch/pjrc-8051/src/up_timerisr.c

@@ -0,0 +1,91 @@
+/************************************************************
+ * up_timerisr.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "clock_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Types
+ ************************************************************/
+
+/************************************************************
+ * Private Function Prototypes
+ ************************************************************/
+
+/************************************************************
+ * Global Functions
+ ************************************************************/
+
+/************************************************************
+ * Function:  timer_isr
+ *
+ * Description:
+ *   The timer ISR will perform a variety of services for
+ *   various portions of the systems.
+ *
+ ************************************************************/
+
+int up_timerisr(int irq, FAR ubyte *frame)
+{
+   /* Process timer interrupt */
+
+   sched_process_timer();
+   return 0;
+}
+
+void up_timerinit(void)
+{
+  up_disable_irq(TIMER2_IRQ);
+
+#warning "Missing TIMER2 setup logic here"
+
+  /* Attach and enable the timer interrupt */
+
+  irq_attach(TIMER2_IRQ, (xcpt_t)up_timerisr);
+  up_enable_irq(TIMER2_IRQ);
+}
+

nuttx/arch/pjrc-8051/src/up_unblocktask.c

@@ -116,27 +116,24 @@ void up_unblock_task(FAR _TCB *tcb)
           * Are we in an interrupt handler? 
           */
 
-          if (g_ininterrupt)
+          if (g_irqtos)
             {
-#if 0
-# warning REVISIT
               /* Yes, then we have to do things differently.
-               * Just copy the current registers into the OLD rtcb.
+               * Just copy the current stack into the OLD rtcb.
                */
 
-               up_copystate(&tcb->xcp, current_regs);
+               up_savestack(&rtcb->xcp);
 
               /* Restore the exception context of the rtcb at the (new) head 
                * of the g_readytorun task list.
                */
 
-              rtcb = (_TCB*)g_readytorun.head;
+              rtcb = (FAR _TCB*)g_readytorun.head;
               dbg("New Active Task TCB=%p\n", rtcb);
 
               /* Then switch contexts */
 
-              up_copystate(current_regs, &tcb->xcp);
+              up_restorestack(&rtcb->xcp);
-#endif
             }
 
          /* We are not in an interrupt andler.  Copy the user C context

nuttx/sched/sched_processtimer.c

@@ -162,12 +162,14 @@ void sched_process_timer(void)
 {
   /* Increment the system time (if in the link) */
 
+#ifndef CONFIG_DISABLE_CLOCK
 #ifdef CONFIG_HAVE_WEAKFUNCTIONS
   if (clock_timer != NULL)
 #endif
     {
       clock_timer();
     }
+#endif
 
   /* Process watchdogs (if in the link) */