configs/p112: Add a configuration for the Z180 P112 board

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5429 42af7a65-404d-4744-a932-0658087f49c3

ChangeLog

@@ -3780,4 +3780,6 @@
 	* include/nuttx/arch.h:  Add address environment control interfaces (for use
 	  with CPUs the provide MCUs and support process-like address environments).
 	* arch/z80/src/z180/z180_mmu.*:  Add MMU support for z180 tasks.
+	* configs/p112:  Add very basic board support and an examples/ostest
+	  configuration for the venerable P112 board.
 

Documentation/README.html

@@ -150,6 +150,8 @@
  |   |   |   |- <a href="http://svn.code.sf.net/p/nuttx/code/trunk/nuttx/configs/olimex-strp711/include/README.txt">include/README.txt</a>
  |   |   |   |- <a href="http://svn.code.sf.net/p/nuttx/code/trunk/nuttx/configs/olimex-strp711/src/README.txt">src/README.txt</a>
  |   |   |   `- <a href="http://svn.code.sf.net/p/nuttx/code/trunk/nuttx/configs/olimex-strp711/README.txt"><b><i>README.txt</i></b></a>
+ |   |   |- p112/
+ |   |   |   `- <a href="http://svn.code.sf.net/p/nuttx/code/trunk/nuttx/configs/p112/README.txt"><b><i>README.txt</i></b></a>
  |   |   |- pcblogic-pic32mx/
  |   |   |   `- <a href="http://svn.code.sf.net/p/nuttx/code/trunk/nuttx/configs/pcblogic-pic32mx/README.txt"><b><i>README.txt</i></b></a>
  |   |   |- pic32-starterkit/

README.txt

@@ -849,6 +849,8 @@ nuttx
  |   |   |- include/README.txt
  |   |   |- src/README.txt
  |   |   `- README.txt
+ |   |- p112/
+ |   |   `- README.txt
  |   |- pcblogic-pic32mx/
  |   |   `- README.txt
  |   |- pic32-starterkit/

arch/z80/src/common/up_doirq.c

@@ -102,6 +102,7 @@ FAR chipreg_t *up_doirq(uint8_t irq, FAR chipreg_t *regs)
 
        IRQ_LEAVE(irq);
     }
+
   up_ledoff(LED_INIRQ);
   return regs;
 #endif

arch/z80/src/common/up_initialize.c

@@ -145,6 +145,14 @@ void up_initialize(void)
   up_timerinit();
 #endif
 
+  /* Initialize the CPU for those that use it (only for the Z180).  This
+   * needs to be done before any tasks are created).
+   */
+
+#if CONFIG_ADDRENV
+  (void)up_mmuinit();
+#endif
+
   /* Register devices */
 
 #if CONFIG_NFILE_DESCRIPTORS > 0

arch/z80/src/common/up_internal.h

@@ -117,6 +117,12 @@ EXTERN FAR chipreg_t *up_doirq(uint8_t irq, FAR chipreg_t *regs);
 
 EXTERN void up_sigdeliver(void);
 
+/* Defined in CPU-specific logic (only for Z180) */
+
+#if CONFIG_ADDRENV
+int up_mmuinit(void);
+#endif
+
 /* Defined in up_allocateheap.c */
 
 #if CONFIG_MM_REGIONS > 1

arch/z80/src/z180/Kconfig

@@ -137,4 +137,17 @@ config ARCH_HAVEHEAD
 		Use a board-specific version of the "head" file in the
 		configs/<board-name>/src directory
 
+menu "Z180 Peripheral Support"
+
+config Z180_UART0
+	bool "UART0"
+	default n
+	select ARCH_HAVE_UART0
+
+config Z180_UART1
+	bool "UART1"
+	default n
+	select ARCH_HAVE_UART1
+
+endmenu
 endif

arch/z80/src/z180/switch.h

@@ -44,6 +44,7 @@
 #include <nuttx/sched.h>
 #include <nuttx/arch.h>
 
+#include "z180_iomap.h"
 #include "up_internal.h"
 
 /************************************************************************************
@@ -58,56 +59,116 @@
 
 /* Initialize the IRQ state */
 
-#define INIT_IRQCONTEXT()        current_regs = NULL
+#define INIT_IRQCONTEXT() \
+  current_regs = NULL
 
 /* IN_INTERRUPT returns true if the system is currently operating in the interrupt
  * context.  IN_INTERRUPT is the inline equivalent of up_interrupt_context().
  */
 
-#define IN_INTERRUPT()           (current_regs != NULL)
+#define IN_INTERRUPT() \
+  (current_regs != NULL)
 
-/* The following macro is used when the system enters interrupt handling logic */
+/* The following macro declares the variables need by IRQ_ENTER and IRQ_LEAVE.
+ * These variables are used to support nested interrupts.
+ *
+ * - savestate holds the previous value of current_state.
+ * - savecpr holds the previous value of current_cpr.
+ *
+ * TODO:  I think this logic is bad... I do not thing that this will really
+ * handle nested interrupts correctly.  What if we are nested and then a
+ * context switch occurs?  current_regs will not be updated correctly!
+ */
 
 #define DECL_SAVESTATE() \
-  FAR chipreg_t *savestate
+  FAR chipreg_t *savestate; \
+  uint8_t savecbr;
+
+/* The following macro is used when the system enters interrupt handling logic.
+ * The entry values of current_regs and current_cbr and stored in local variables.
+ * Then current_regs and current_cbr are set to the values of the interrupted
+ * task.
+ */
 
 #define IRQ_ENTER(irq, regs) \
-  do { \
+  do \
-    savestate    = (FAR chipreg_t *)current_regs; \
+    { \
-    current_regs = (regs); \
+      savestate    = (FAR chipreg_t *)current_regs; \
-  } while (0)
+      savecbr      = current_cbr; \
+      current_regs = (regs); \
+      current_cbr  = inp(Z180_MMU_CBR); \
+    } \
+  while (0)
 
-/* The following macro is used when the system exits interrupt handling logic */
+/* The following macro is used when the system exits interrupt handling logic.
+ * The value of current_regs is restored.  If we are not processing a nested
+ * interrupt (meaning that we going to return to the user task), then also
+ * set the MMU's CBR register.
+ */
 
-#define IRQ_LEAVE(irq)           current_regs = savestate
+#define IRQ_LEAVE(irq) \
+  do \
+    { \
+      current_regs = savestate; \
+      if (current_regs) \
+        { \
+          current_cbr  = savecbr; \
+        } \
+      else \
+        { \
+          outp(Z180_MMU_CBR, savecbr); \
+        } \
+    }
 
 /* The following macro is used to sample the interrupt state (as a opaque handle) */
 
-#define IRQ_STATE()              (current_regs)
+#define IRQ_STATE() \
+  (current_regs)
 
 /* Save the current IRQ context in the specified TCB */
 
-#define SAVE_IRQCONTEXT(tcb)     z180_copystate((tcb)->xcp.regs, (FAR chipreg_t*)current_regs)
+#define SAVE_IRQCONTEXT(tcb) \
+  z180_copystate((tcb)->xcp.regs, (FAR chipreg_t*)current_regs)
 
 /* Set the current IRQ context to the state specified in the TCB */
 
-#define SET_IRQCONTEXT(tcb)      z180_copystate((FAR chipreg_t*)current_regs, (tcb)->xcp.regs)
+#define SET_IRQCONTEXT(tcb) \
+  do \
+    { \
+      if ((tcb)->xcp.cbr.cbr) \
+        { \
+          current_cbr = (tcb)->xcp.cbr->cbr); \
+        } \
+      z180_copystate((FAR chipreg_t*)current_regs, (tcb)->xcp.regs); \
+    } \
+  while (0)
 
 /* Save the user context in the specified TCB.  User context saves can be simpler
  * because only those registers normally saved in a C called need be stored.
  */
 
-#define SAVE_USERCONTEXT(tcb)    z180_saveusercontext((tcb)->xcp.regs)
+#define SAVE_USERCONTEXT(tcb)  \
+  z180_saveusercontext((tcb)->xcp.regs)
 
 /* Restore the full context -- either a simple user state save or the full,
  * IRQ state save.
  */
 
-#define RESTORE_USERCONTEXT(tcb) z180_restoreusercontext((tcb)->xcp.regs)
+#define RESTORE_USERCONTEXT(tcb) \
+  do \
+    { \
+      if ((tcb)->xcp.cbr.cbr) \
+        { \
+          outp(Z180_MMU_CBR, (tcb)->xcp.cbr->cbr); \
+        } \
+      z180_restoreusercontext((tcb)->xcp.regs); \
+    } \
+  while (0)
 
 /* Dump the current machine registers */
 
-#define _REGISTER_DUMP()         z180_registerdump()
+#define _REGISTER_DUMP() \
+  z180_registerdump()
 
 /************************************************************************************
  * Public Types
@@ -123,6 +184,14 @@
  */
 
 extern volatile chipreg_t *current_regs;
+
+/* This holds the value of the MMU's CBR register.  This value is set to the
+ * interrupted tasks's CBR on interrupt entry, changed to the new task's CBR if
+ * an interrrupt level context switch occurs, and restored on interrupt exit.  In
+ * this way, the CBR is always correct on interrupt exit.
+ */
+
+extern uint8_t current_cbr;
 #endif
 
 /************************************************************************************

arch/z80/src/z180/z180_mmu.c

@@ -120,15 +120,21 @@ static FAR struct z180_cbr_s *z180_mmu_findcbr(void)
  *   called very early in the boot process to get the basic operating
  *   memory configuration correct.  This function does *not* perform all
  *   necessray MMU initialization... only the basics needed at power-up.
- *   z180_mmu_init() must be called later to complete the entire MMU
+ *   up_mmuinit() must be called later to complete the entire MMU
  *   initialization.
  *
  ****************************************************************************/
 
 void z180_mmu_lowinit(void) __naked
 {
+  /* Set the CBAR register to set up the virtual address of the Bank Area and
+   * Common Area 1.  Set the BBR register to set up the physical mapping for
+   * the Bank Area (the physical mapping for Common Area 1 will not be done
+   * until the first task is started.
+   */
+
   __asm
-	ld	c, #Z180_MMU_CBR		; port
+	ld	c, #Z180_MMU_CBAR		; port
 	ld	a, #Z180_CBAR_VALUE		; value
 	out	(c), a
 
@@ -139,15 +145,15 @@ void z180_mmu_lowinit(void) __naked
 }
 
 /****************************************************************************
- * Name: z180_mmu_init
+ * Name: up_mmuinit
  *
  * Description:
- *   Perform higher level initializatin of the MMU and physical memory
+ *   Perform higher level initialization of the MMU and physical memory
  *   memory management logic.
  *
  ****************************************************************************/
 
-int z180_mmu_init(void)
+int up_mmuinit(void)
 {
   /* Here we use the granule allocator as a page allocator.  We lie and
    * say that 1 page is 1 byte.
@@ -257,7 +263,7 @@ errout_with_irq:
 }
 
 /****************************************************************************
- * Name: up_addrenv_clone
+ * Name: up_addrenv_share
  *
  * Description:
  *   This function is called from the core scheduler logic when a thread
@@ -274,8 +280,7 @@ errout_with_irq:
  *
  ****************************************************************************/
 
-#ifdef CONFIG_ADDRENV
+int up_addrenv_share(FAR const _TCB *ptcb, FAR _TCB *ctcb)
-int up_addrenv_clone(FAR const _TCB *ptcb, FAR _TCB *ctcb)
 {
   irqstate_t flags;
 
@@ -299,7 +304,6 @@ int up_addrenv_clone(FAR const _TCB *ptcb, FAR _TCB *ctcb)
   irqrestore(flags);
   return OK;
 }
-#endif
 
 /****************************************************************************
  * Name: up_addrenv_instantiate
@@ -316,35 +320,55 @@ int up_addrenv_clone(FAR const _TCB *ptcb, FAR _TCB *ctcb)
  *     be instantiated.
  *
  * Returned Value:
+ *   A handle that may be used with up_addrenv_restore() to restore the
+ *   address environment before up_addrenv_instantiate() was called.
+ *
+ ****************************************************************************/
+
+FAR void *up_addrenv_instantiate(FAR _TCB *tcb)
+{
+  uint8_t oldcbr;
+  irqstate_t flags;
+
+  /* Get the current CBR value from the CBR register */
+
+  flags = irqsave();
+  cbr = inp(Z180_MMU_CBR);
+
+  /* Check if the task has an address environment. */
+
+  if (tcb->xcp.cbr)
+    {
+      /* Yes.. Write the new CBR value into CBR register */
+
+      outp(Z180_MMU_CBR, tcb->xcp.cbr.cbr);
+    }
+
+  irqrestore(flags);
+  return (FAR void *)cbr;
+}
+
+/****************************************************************************
+ * Name: up_addrenv_restore
+ *
+ * Description:
+ *   Restore an address environment using a handle previously returned by
+ *   up_addrenv_instantiate().
+ *
+ * Input Parameters:
+ *   handle - A handle previously returned by up_addrenv_instantiate.
+ *
+ * Returned Value:
  *   Zero (OK) on success; a negated errno value on failure.
  *
  ****************************************************************************/
 
-#ifdef CONFIG_ADDRENV
+int up_addrenv_restore(FAR void *handle)
-int up_addrenv_instantiate(FAR _TCB *tcb)
 {
-  irqstate_t flags;
+  /* Restore the CBR value */
 
-  /* Check if the task has an address environment. */
+  outp(Z180_MMU_CBR, (uint8_t)handle);
-
-  flags = irqsave();
-  if (tcb->xcp.cbr)
-    {
-      /* Yes... write the CBR value into CBR register */
-
-      outp(Z180_MMU_CBR, tcb->xcp.cbr.cbr);
-      /* Clone the CBR by incrementing the reference counting and saving a
-       * copy in the child thread's TCB.
-       */
-
-      ptcb->xcp.cbr.crefs++;
-      ctcb->xcp.cbr = ptcb->xcp.cbr;
-    }
-
-  irqrestore(flags);
-  return OK;
 }
-#endif
 
 /****************************************************************************
  * Name: up_addrenv_release
@@ -364,7 +388,6 @@ int up_addrenv_instantiate(FAR _TCB *tcb)
  *
  ****************************************************************************/
 
-#ifdef CONFIG_ADDRENV
 int up_addrenv_release(FAR _TCB *tcb)
 {
   FAR struct z180_cbr_s *cbr;
@@ -401,5 +424,3 @@ int up_addrenv_release(FAR _TCB *tcb)
   irqrestore(flags);
   return OK;
 }
-#endif
-

arch/z80/src/z180/z180_mmu.h

@@ -128,7 +128,7 @@
  *   called very early in the boot process to get the basic operating
  *   memory configuration correct.  This function does *not* perform all
  *   necessray MMU initialization... only the basics needed at power-up.
- *   z180_mmu_init() must be called later to complete the entire MMU
+ *   up_mmuinit() must be called later to complete the entire MMU
  *   initialization.
  *
  ****************************************************************************/
@@ -136,7 +136,7 @@
 void z180_mmu_lowinit(void) __naked;
 
 /****************************************************************************
- * Name: z180_mmu_init
+ * Name: up_mmuinit
  *
  * Description:
  *   Perform higher level initializatin of the MMU and physical memory
@@ -144,6 +144,6 @@ void z180_mmu_lowinit(void) __naked;
  *
  ****************************************************************************/
 
-void z180_mmu_init(void);
+void up_mmuinit(void);
 
 #endif /* __ARCH_Z80_SRC_Z180_Z180_MMU_H */

arch/z80/src/z180/z180_registerdump.c

@@ -86,6 +86,8 @@ static void z180_registerdump(void)
             current_regs[XCPT_IX], current_regs[XCPT_IY]);
       lldbg("SP: %04x PC: %04x\n"
             current_regs[XCPT_SP], current_regs[XCPT_PC]);
+      lldbg("CBAR: %02x BBR: %02x CBR: %02x\n"
+            inp(Z180_MMU_CBAR), inp(Z180_MMU_BBR), inp(Z180_MMU_CBR));
     }
 }
 #endif

configs/Kconfig

@@ -346,6 +346,33 @@ config ARCH_BOARD_OLIMEX_STM32P107
 		Linux or Cygwin. See the http://www.olimex.com for further information. This
 		board features the STMicro STM32F107VC MCU
 
+config ARCH_BOARD_P112
+	bool "P112 Z180-based platform"
+	depends on ARCH_CHIP_Z8018216FSG
+	---help---
+		The P112 is notable because it was the first of the hobbyist single board
+		computers to reach the production stage. The P112 hobbyist computers
+		were relatively widespread and inspired other hobbyist centered home brew
+		computing projects such as N8VEM home brew computing project. The P112
+		project still maintains many devoted enthusiasts and has an online
+		repository of software and other information.
+
+		The P112 computer originated as a commercial product of "D-X Designs Pty
+		Ltd" of Australia. They describe the computer as "The P112 is a stand-alone
+		8-bit CPU board. Typically running CP/M (tm) or a similar operating system,
+		it provides a Z80182 (Z-80 upgrade) CPU with up to 1MB of memory, serial,
+		parallel and diskette IO, and realtime clock, in a 3.5-inch drive form factor.
+		Powered solely from 5V, it draws 150mA (nominal: not including disk drives)
+		with a 16MHz CPU clock. Clock speeds up to 24.576MHz are possible."
+
+		The P112 board was last available new in 1996 by Dave Brooks. In late 2004
+		on the Usenet Newsgroup comp.os.cpm, talk about making another run of P112
+		boards was discussed. David Griffith decided to produce additional P112 kits
+		with Dave Brooks blessing and the assistance of others. In addition Terry
+		Gulczynski makes additional P112 derivative hobbyist home brew computers.
+		Hal Bower was very active in the mid 1990's on the P112 project and ported
+		the "Banked/Portable BIOS".
+
 config ARCH_BOARD_PCBLOGICPIC32MX
 	bool "PIC32MX board from PCB Logic Design Co"
 	depends on ARCH_CHIP_PIC32MX460F512L
@@ -647,6 +674,7 @@ config ARCH_BOARD
 	default "olimex-lpc2378"      if ARCH_BOARD_OLIMEXLPC2378
 	default "olimex-stm32-p107"   if ARCH_BOARD_OLIMEX_STM32P107
 	default "olimex-strp711"      if ARCH_BOARD_OLIMEX_STRP711
+	default "p112"                if ARCH_BOARD_P112
 	default "pcblogic-pic32mx"    if ARCH_BOARD_PCBLOGICPIC32MX
 	default "pic32-starterkit"    if ARCH_BOARD_PIC32_STARTERKIT
 	default "pic32mx7mmb"         if ARCH_BOARD_PIC32_PIC32MX7MMB

configs/README.txt

@@ -1780,14 +1780,36 @@ configs/pcblogic-pic32mx
   STATUS:  Code complete but testing has been stalled due to tool related problems
   (PICkit 2 does not work with the PIC32).
 
-configs/pic32-starterkit
+configs/p112
+  The P112 is notable because it was the first of the hobbyist single board
+  computers to reach the production stage. The P112 hobbyist computers
+  were relatively widespread and inspired other hobbyist centered home brew
+  computing projects such as N8VEM home brew computing project. The P112
+  project still maintains many devoted enthusiasts and has an online
+  repository of software and other information.
 
+  The P112 computer originated as a commercial product of "D-X Designs Pty
+  Ltd" of Australia. They describe the computer as "The P112 is a stand-alone
+  8-bit CPU board. Typically running CP/M (tm) or a similar operating system,
+  it provides a Z80182 (Z-80 upgrade) CPU with up to 1MB of memory, serial,
+  parallel and diskette IO, and realtime clock, in a 3.5-inch drive form factor.
+  Powered solely from 5V, it draws 150mA (nominal: not including disk drives)
+  with a 16MHz CPU clock. Clock speeds up to 24.576MHz are possible."
+
+  The P112 board was last available new in 1996 by Dave Brooks. In late 2004
+  on the Usenet Newsgroup comp.os.cpm, talk about making another run of P112
+  boards was discussed. David Griffith decided to produce additional P112 kits
+  with Dave Brooks blessing and the assistance of others. In addition Terry
+  Gulczynski makes additional P112 derivative hobbyist home brew computers.
+  Hal Bower was very active in the mid 1990's on the P112 project and ported
+  the "Banked/Portable BIOS".
+
+configs/pic32-starterkit
   This directory contains the port of NuttX to the Microchip PIC32 Ethernet
   Starter Kit (DM320004) with the Multimedia Expansion Board (MEB, DM320005).
   See www.microchip.com for further information.
 
 configs/pic32mx7mmb
-
   This directory will (eventually) contain the port of NuttX to the
   Mikroelektronika PIC32MX7 Multimedia Board (MMB).  See
   http://www.mikroe.com/ for further information.
@@ -1797,7 +1819,6 @@ configs/pjrc-8051
   and the SDCC toolchain.   This port is not quite ready for prime time.
 
 configs/qemu-i486
-
   Port of NuttX to QEMU in i486 mode.  This port will also run on real i486
   hardwared (Google the Bifferboard).
 

configs/p112/Kconfig

@@ -0,0 +1,4 @@
+#
+# For a description of the syntax of this configuration file,
+# see misc/tools/kconfig-language.txt.
+#

configs/p112/README.txt

@@ -0,0 +1,26 @@
+P112 README
+^^^^^^^^^^^
+
+The P112 is notable because it was the first of the hobbyist single board
+computers to reach the production stage. The P112 hobbyist computers
+were relatively widespread and inspired other hobbyist centered home brew
+computing projects such as N8VEM home brew computing project. The P112
+project still maintains many devoted enthusiasts and has an online
+repository of software and other information.
+
+The P112 computer originated as a commercial product of "D-X Designs Pty
+Ltd" of Australia. They describe the computer as "The P112 is a stand-alone
+8-bit CPU board. Typically running CP/M (tm) or a similar operating system,
+it provides a Z80182 (Z-80 upgrade) CPU with up to 1MB of memory, serial,
+parallel and diskette IO, and realtime clock, in a 3.5-inch drive form factor.
+Powered solely from 5V, it draws 150mA (nominal: not including disk drives)
+with a 16MHz CPU clock. Clock speeds up to 24.576MHz are possible."
+
+The P112 board was last available new in 1996 by Dave Brooks. In late 2004
+on the Usenet Newsgroup comp.os.cpm, talk about making another run of P112
+boards was discussed. David Griffith decided to produce additional P112 kits
+with Dave Brooks blessing and the assistance of others. In addition Terry
+Gulczynski makes additional P112 derivative hobbyist home brew computers.
+Hal Bower was very active in the mid 1990's on the P112 project and ported
+the "Banked/Portable BIOS".
+

configs/p112/include/board.h

@@ -0,0 +1,60 @@
+/************************************************************
+ * configs/p112/include/board.h
+ *
+ *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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 NuttX 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.
+ *
+ ************************************************************/
+
+#ifndef __CONFIGS_P112_INCLUDE_BOARD_H
+#define __CONFIGS_P112_INCLUDE_BOARD_H
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+#if defined(__cplusplus)
+extern "C"
+{
+#endif
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif  /* __CONFIGS_P112_INCLUDE_BOARD_H */

configs/p112/ostest/Make.defs

@@ -0,0 +1,167 @@
+############################################################################
+# configs/p112/ostest/Make.defs
+#
+#   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+#   Author: Gregory Nutt <gnutt@nuttx.org>
+#
+# 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 NuttX 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.
+#
+############################################################################
+
+include ${TOPDIR}/.config
+include ${TOPDIR}/tools/Config.mk
+
+# These are the directories where the SDCC toolchain is installed.  NOTE
+# that short 8.3 path names are used in order to avoid spaces.  On my machine
+# I have:
+#
+# C:\PROGRA~1\ = C:\Profram Files\
+# C:\PROGRA~2\ = C:\Program Files (x86)\
+#
+# Your PC may be configured differently.
+
+ifeq ($(CONFIG_WINDOWS_NATIVE),y)
+  SDCC_INSTALLDIR = C:\PROGRA~2\SDCC
+  SDCC_BINDIR = $(SDCC_INSTALLDIR)\bin
+  SDCC_LIBDIR = $(SDCC_INSTALLDIR)\lib\z180
+else
+  SDCC_INSTALLDIR = /usr/local
+  SDCC_BINDIR = $(SDCC_INSTALLDIR)/bin
+  SDCC_LIBDIR = $(SDCC_INSTALLDIR)/share/sdcc/lib/z180
+endif
+
+CROSSDEV =
+CC = sdcc
+CPP = sdcpp
+LD = sdldz80
+AS = sdasz80
+AR = sdar -r
+ARCHCPUFLAGS = -mz180
+
+ifeq ($(CONFIG_DEBUG_SYMBOLS),y)
+  ARCHOPTIMIZATION = --debug
+else
+  ARCHOPTIMIZATION =
+endif
+
+ARCHPICFLAGS =
+ARCHWARNINGS =
+ARCHDEFINES =
+ARCHINCLUDES = -I. -I$(TOPDIR)$(DELIM)include
+
+CFLAGS = $(ARCHWARNINGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARCHINCLUDES) $(ARCHDEFINES) $(EXTRADEFINES)
+CPPFLAGS = $(ARCHINCLUDES) $(ARCHDEFINES) $(EXTRADEFINES)
+AFLAGS = -x -a -l -o -s -g
+
+SDCCLIB = z180.lib
+
+ASMEXT = .asm
+OBJEXT = .o
+LIBEXT = .lib
+EXEEXT = .hex
+
+# Custom ASSEMBLE definition.  The most common toolchain, GCC, uses the
+# compiler to assemble files because this has the advantage of running the C
+# Pre-Processor against.  This is not possible with other SDCC; we need to
+# define AS and over-ride the common definition in order to use the assembler
+# directly.
+
+define ASSEMBLE
+	@echo "AS: $1"
+	$(Q) $(AS) $(AFLAGS) $2 $1
+endef
+
+# Custom CLEAN definition
+
+ifeq ($(CONFIG_WINDOWS_NATIVE),y)
+define CLEAN
+	$(Q) if exist *.o (del /f /q *.o)
+	$(Q) if exist *.asm (del /f /q *.asm)
+	$(Q) if exist *.rel (del /f /q *.rel)
+	$(Q) if exist *.lst (del /f /q *.lst)
+	$(Q) if exist *.rst (del /f /q *.rst)
+	$(Q) if exist *.sym (del /f /q *.sym)
+	$(Q) if exist *.adb (del /f /q *.adb)
+	$(Q) if exist *.lnk (del /f /q *.lnk)
+	$(Q) if exist *.map (del /f /q *.map)
+	$(Q) if exist *.mem (del /f /q *.mem)
+	$(Q) if exist *.hex (del /f /q *.hex)
+	$(Q) if exist *.cmd (del /f /q *.cmd)
+endef
+else
+define CLEAN
+	$(Q) rm -f *.o *.asm *.rel *.lst *.rst *.sym *.adb *.lnk *.map *.mem *.hex *.cmd
+endef
+endif
+
+# Windows native host tool definitions
+
+ifeq ($(CONFIG_WINDOWS_NATIVE),y)
+  HOSTCC = mingw32-gcc.exe
+  HOSTINCLUDES = -I.
+  HOSTCFLAGS = -Wall -Wstrict-prototypes -Wshadow -g -pipe
+  HOSTLDFLAGS =
+  HOSTEXEEXT = .exe
+
+  # Windows-native host tools
+
+  MKDEP = $(TOPDIR)\tools\mkdeps.exe --winnative
+
+  # Use NTFS links or directory copies
+
+ifeq ($(CONFIG_WINDOWS_MKLINK),y)
+  DIRLINK = $(TOPDIR)$(DELIM)tools$(DELIM)link.bat
+else
+  DIRLINK = $(TOPDIR)$(DELIM)tools$(DELIM)copydir.bat
+endif
+DIRUNLINK = $(TOPDIR)$(DELIM)tools$(DELIM)unlink.bat
+
+else
+
+# Linux/Cygwin host tool definitions
+
+  HOSTCC = gcc
+  HOSTINCLUDES = -I.
+  HOSTCFLAGS = -Wall -Wstrict-prototypes -Wshadow -g -pipe
+  HOSTLDFLAGS =
+
+  # This is the tool to use for dependencies (i.e., none)
+
+  MKDEP = $(TOPDIR)$(DELIM)tools$(DELIM)mknulldeps.sh
+
+  # SDCC for Linux, OSX, or Cygwin understands symbolic links.  Windows SDCC
+  # running under Cygwin does not
+
+ifeq ($(WINTOOL),y)
+  DIRLINK = $(TOPDIR)$(DELIM)tools$(DELIM)copydir.sh
+else
+  DIRLINK = $(TOPDIR)$(DELIM)tools$(DELIM)link.sh
+endif
+DIRUNLINK = $(TOPDIR)$(DELIM)tools$(DELIM)unlink.sh
+
+endif

configs/p112/ostest/setenv.bat

@@ -0,0 +1,50 @@
+@echo off
+
+rem configs/p112/ostest/setenv.bat
+rem
+rem   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+rem   Author: Gregory Nutt <gnutt@nuttx.org>
+rem
+rem Redistribution and use in source and binary forms, with or without
+rem modification, are permitted provided that the following conditions
+rem are met:
+rem
+rem 1. Redistributions of source code must retain the above copyright
+rem    notice, this list of conditions and the following disclaimer.
+rem 2. Redistributions in binary form must reproduce the above copyright
+rem    notice, this list of conditions and the following disclaimer in
+rem    the documentation and/or other materials provided with the
+rem    distribution.
+rem 3. Neither the name NuttX nor the names of its contributors may be
+rem    used to endorse or promote products derived from this software
+rem    without specific prior written permission.
+rem
+rem THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+rem "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+rem LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+rem FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+rem COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+rem INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+rem BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+rem OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+rem AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+rem LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+rem ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+rem POSSIBILITY OF SUCH DAMAGE.
+
+rem This is the location where I installed in the MinGW compiler. With
+rem this configuration, it is recommended that you do NOT install the
+rem MSYS tools; they conflict with the GNUWin32 tools.  See
+rem http://www.mingw.org/ for further info.
+
+set PATH=C:\MinGW\bin;%PATH%
+
+rem This is the location where I installed the SDCC toolchain for windows.
+
+set PATH=C:\Program Files (x86)\SDCC/bin;%PATH%
+
+rem This is the location where I installed the GNUWin32 tools.  See
+rem http://gnuwin32.sourceforge.net/.
+
+set PATH=C:\gnuwin32\bin;%PATH%
+echo %PATH%

configs/p112/scripts/setenv.bat

@@ -0,0 +1,50 @@
+@echo off
+
+rem configs/p112/scripts/setenv.bat
+rem
+rem   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+rem   Author: Gregory Nutt <gnutt@nuttx.org>
+rem
+rem Redistribution and use in source and binary forms, with or without
+rem modification, are permitted provided that the following conditions
+rem are met:
+rem
+rem 1. Redistributions of source code must retain the above copyright
+rem    notice, this list of conditions and the following disclaimer.
+rem 2. Redistributions in binary form must reproduce the above copyright
+rem    notice, this list of conditions and the following disclaimer in
+rem    the documentation and/or other materials provided with the
+rem    distribution.
+rem 3. Neither the name NuttX nor the names of its contributors may be
+rem    used to endorse or promote products derived from this software
+rem    without specific prior written permission.
+rem
+rem THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+rem "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+rem LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+rem FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+rem COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+rem INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+rem BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+rem OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+rem AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+rem LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+rem ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+rem POSSIBILITY OF SUCH DAMAGE.
+
+rem This is the location where I installed in the MinGW compiler. With
+rem this configuration, it is recommended that you do NOT install the
+rem MSYS tools; they conflict with the GNUWin32 tools.  See
+rem http://www.mingw.org/ for further info.
+
+set PATH=C:\MinGW\bin;%PATH%
+
+rem This is the location where I installed the SDCC toolchain for windows.
+
+set PATH=C:\Program Files (x86)\SDCC/bin;%PATH%
+
+rem This is the location where I installed the GNUWin32 tools.  See
+rem http://gnuwin32.sourceforge.net/.
+
+set PATH=C:\gnuwin32\bin;%PATH%
+echo %PATH%

configs/p112/scripts/setenv.sh

@@ -0,0 +1,66 @@
+#!/bin/bash
+# configs/p112/ostest/setenv.sh
+#
+#   Copyright (C) 2007, 2008, 2012 Gregory Nutt. All rights reserved.
+#   Author: Gregory Nutt <gnutt@nuttx.org>
+#
+# 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 NuttX 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.
+#
+
+if [ "$_" = "$0" ] ; then
+  echo "You must source this script, not run it!" 1>&2
+  exit 1
+fi
+
+WD=`pwd`
+if [ ! -x "setenv.sh" ]; then
+  echo "This script must be executed from the top-level NuttX build directory"
+  exit 1
+fi
+
+if [ -z "${PATH_ORIG}" ]; then
+  export PATH_ORIG="${PATH}"
+fi
+
+#
+# This is the normal installation directory for SDCC under Linux, OSX
+# or Linux:
+#
+export TOOLCHAIN_BIN=/usr/local/bin
+
+#
+# This is the normal installation directory for SDCC under Windows
+#
+#export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/SDCC/bin"
+
+#
+# Add the path to the toolchain to the PATH varialble
+#
+export PATH="${TOOLCHAIN_BIN}":/sbin:/usr/sbin:${PATH_ORIG}
+
+echo "PATH : ${PATH}"

configs/p112/src/Makefile

@@ -0,0 +1,77 @@
+############################################################################
+# configs/p112/src/Makefile
+#
+#   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+#   Author: Gregory Nutt <gnutt@nuttx.org>
+#
+# 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 NuttX 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.
+#
+############################################################################
+
+-include $(TOPDIR)/Make.defs
+
+CFLAGS		+= -I$(TOPDIR)$(DELIM)sched
+CFLAGS		+= -I$(TOPDIR)$(DELIM)arch$(DELIM)z80$(DELIM)src$(DELIM)common
+CFLAGS		+= -I$(TOPDIR)$(DELIM)arch$(DELIM)z80$(DELIM)src$(DELIM)z180
+
+ASRCS		= 
+AOBJS		= $(ASRCS:$(ASMEXT)=$(OBJEXT))
+CSRCS		= 
+COBJS		= $(CSRCS:.c=$(OBJEXT))
+
+SRCS		= $(ASRCS) $(CSRCS)
+OBJS		= $(AOBJS) $(COBJS)
+
+CFLAGS		+= -I $(TOPDIR)$(DELIM)arch$(DELIM)$(CONFIG_ARCH)$(DELIM)src
+
+all: libboard$(LIBEXT)
+
+$(AOBJS): %$(OBJEXT): %$(ASMEXT)
+	$(call ASSEMBLE, $<, $@)
+
+$(COBJS) $(LINKOBJS): %$(OBJEXT): %.c
+	$(call COMPILE, $<, $@)
+
+libboard$(LIBEXT): $(OBJS)
+	$(call ARCHIVE, $@, $(OBJS))
+
+.depend: Makefile $(SRCS)
+	$(Q) $(MKDEP) $(CC) -- $(CFLAGS) -- $(SRCS) >Make.dep
+	$(Q) touch $@
+
+depend: .depend
+
+clean:
+	$(call DELFILE, libboard$(LIBEXT))
+	$(call CLEAN)
+
+distclean: clean
+	$(call DELFILE, Make.dep)
+	$(call DELFILE, .depend)
+
+-include Make.dep

configs/z80sim/src/Makefile

@@ -36,7 +36,7 @@
 -include $(TOPDIR)/Make.defs
 
 CFLAGS		+= -I$(TOPDIR)$(DELIM)sched
-CFLAGS		+= -I$(TOPDIR)$(DELIM)arch$(DELIM)z80$(DELIM)src$(DELIM)common -I$(TOPDIR)$(DELIM)arch$(DELIM)z80$(DELIM)src$(DELIM)z80
+CFLAGS		+= -I$(TOPDIR)$(DELIM)arch$(DELIM)z80$(DELIM)src$(DELIM)common
 CFLAGS		+= -I$(TOPDIR)$(DELIM)arch$(DELIM)z80$(DELIM)src$(DELIM)z80
 
 ASRCS		= 

include/nuttx/arch.h

@@ -403,7 +403,7 @@ int up_addrenv_create(FAR _TCB *tcb, size_t envsize);
 #endif
 
 /****************************************************************************
- * Name: up_addrenv_clone
+ * Name: up_addrenv_share
  *
  * Description:
  *   This function is called from the core scheduler logic when a thread
@@ -421,7 +421,7 @@ int up_addrenv_create(FAR _TCB *tcb, size_t envsize);
  ****************************************************************************/
 
 #ifdef CONFIG_ADDRENV
-int up_addrenv_clone(FAR const _TCB *ptcb, FAR _TCB *ctcb);
+int up_addrenv_share(FAR const _TCB *ptcb, FAR _TCB *ctcb);
 #endif
 
 /****************************************************************************
@@ -439,12 +439,32 @@ int up_addrenv_clone(FAR const _TCB *ptcb, FAR _TCB *ctcb);
  *     be instantiated.
  *
  * Returned Value:
+ *   A handle that may be used with up_addrenv_restore() to restore the
+ *   address environment before up_addrenv_instantiate() was called.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_ADDRENV
+FAR void *up_addrenv_instantiate(FAR _TCB *tcb);
+#endif
+
+/****************************************************************************
+ * Name: up_addrenv_restore
+ *
+ * Description:
+ *   Restore an address environment using a handle previously returned by
+ *   up_addrenv_instantiate().
+ *
+ * Input Parameters:
+ *   handle - A handle previously returned by up_addrenv_instantiate.
+ *
+ * Returned Value:
  *   Zero (OK) on success; a negated errno value on failure.
  *
  ****************************************************************************/
 
 #ifdef CONFIG_ADDRENV
-int up_addrenv_instantiate(FAR _TCB *tcb);
+int up_addrenv_restore(FAR void *handle);
 #endif
 
 /****************************************************************************

sched/Kconfig

@@ -22,7 +22,13 @@ config SCHED_INSTRUMENTATION
 	bool "Monitor system performance"
 	default n
 	---help---
-		enables instrumentation in scheduler to monitor system performance.
+		Enables instrumentation in scheduler to monitor system performance.
+		If enabled, then the board-specific logic must provide the following
+		functions (see include/sched.h):
+
+		void sched_note_start(FAR _TCB *tcb);
+		void sched_note_stop(FAR _TCB *tcb);
+		void sched_note_switch(FAR _TCB *pFromTcb, FAR _TCB *pToTcb);
 
 config TASK_NAME_SIZE
 	int "Maximum task name size"

sched/env_internal.h

@@ -80,7 +80,7 @@ EXTERN int env_dup(FAR _TCB *ptcb);
 EXTERN int env_share(FAR _TCB *ptcb);
 EXTERN int env_release(FAR _TCB *ptcb);
 
-/* functions used internally the environment handling logic */
+/* functions used internally by the environment handling logic */
 
 EXTERN FAR char *env_findvar(environ_t *envp, const char *pname);
 EXTERN int env_removevar(environ_t *envp, char *pvar);

sched/pthread_create.c

@@ -246,7 +246,7 @@ int pthread_create(FAR pthread_t *thread, FAR pthread_attr_t *attr,
 {
   FAR _TCB *ptcb;
   FAR join_t *pjoin;
-  int status;
+  int ret;
   int priority;
 #if CONFIG_RR_INTERVAL > 0
   int policy;
@@ -268,13 +268,27 @@ int pthread_create(FAR pthread_t *thread, FAR pthread_attr_t *attr,
       return ENOMEM;
     }
 
-  /* Associate file descriptors with the new task */
+  /* Share the address environment of the parent task.  NOTE:  Only tasks
+   * created throught the nuttx/binfmt loaders may have an address
+   * environment.
+   */
 
-  status = sched_setuppthreadfiles(ptcb);
+#ifdef CONFIG_ADDRENV
-  if (status != OK)
+  ret = up_addrenv_share((FAR const _TCB *)g_readytorun.head, ptcb);
+  if (ret < 0)
     {
       sched_releasetcb(ptcb);
-      return status;
+      return -ret;
+    }
+#endif
+
+  /* Associate file descriptors with the new task */
+
+  ret = sched_setuppthreadfiles(ptcb);
+  if (ret != OK)
+    {
+      sched_releasetcb(ptcb);
+      return ret;
     }
 
   /* Share the parent's envionment */
@@ -292,8 +306,8 @@ int pthread_create(FAR pthread_t *thread, FAR pthread_attr_t *attr,
 
   /* Allocate the stack for the TCB */
 
-  status = up_create_stack(ptcb, attr->stacksize);
+  ret = up_create_stack(ptcb, attr->stacksize);
-  if (status != OK)
+  if (ret != OK)
     {
       sched_releasetcb(ptcb);
       sched_free(pjoin);
@@ -310,8 +324,8 @@ int pthread_create(FAR pthread_t *thread, FAR pthread_attr_t *attr,
       /* Get the priority for this thread. */
 
       struct sched_param param;
-      status = sched_getparam(0, &param);
+      ret = sched_getparam(0, &param);
-      if (status == OK)
+      if (ret == OK)
         {
           priority = param.sched_priority;
         }
@@ -348,11 +362,9 @@ int pthread_create(FAR pthread_t *thread, FAR pthread_attr_t *attr,
 
   /* Initialize the task control block */
 
-  status  = task_schedsetup(ptcb, priority, pthread_start,
+  ret  = task_schedsetup(ptcb, priority, pthread_start, (main_t)start_routine);
-                            (main_t)start_routine);
+  if (ret != OK)
-  if (status != OK)
     {
-
       sched_releasetcb(ptcb);
       sched_free(pjoin);
       return EBUSY;
@@ -390,21 +402,21 @@ int pthread_create(FAR pthread_t *thread, FAR pthread_attr_t *attr,
 
   /* Initialize the semaphores in the join structure to zero. */
 
-  status = sem_init(&pjoin->data_sem, 0, 0);
+  ret = sem_init(&pjoin->data_sem, 0, 0);
-  if (status == OK)
+  if (ret == OK)
     {
-      status = sem_init(&pjoin->exit_sem, 0, 0);
+      ret = sem_init(&pjoin->exit_sem, 0, 0);
     }
 
   /* Activate the task */
 
   sched_lock();
-  if (status == OK)
+  if (ret == OK)
     {
-      status = task_activate(ptcb);
+      ret = task_activate(ptcb);
     }
 
-  if (status == OK)
+  if (ret == OK)
     {
       /* Wait for the task to actually get running and to register
        * its join_t
@@ -414,8 +426,15 @@ int pthread_create(FAR pthread_t *thread, FAR pthread_attr_t *attr,
 
       /* Return the thread information to the caller */
 
-      if (thread) *thread = (pthread_t)pid;
+      if (thread)
-      if (!pjoin->started) status = ERROR;
+       {
+         *thread = (pthread_t)pid;
+       }
+
+      if (!pjoin->started)
+        {
+          ret = EINVAL;
+        }
 
       sched_unlock();
       (void)sem_destroy(&pjoin->data_sem);
@@ -428,8 +447,8 @@ int pthread_create(FAR pthread_t *thread, FAR pthread_attr_t *attr,
       (void)sem_destroy(&pjoin->exit_sem);
       sched_releasetcb(ptcb);
       sched_free(pjoin);
-      return EIO;
+      ret = EIO;
     }
 
-  return OK;
+  return ret;
 }

sched/sched_releasetcb.c

@@ -171,6 +171,12 @@ int sched_releasetcb(FAR _TCB *tcb)
 
       (void)env_release(tcb);
 
+      /* Release this thread's reference to the address environment */
+
+#ifdef CONFIG_ADDRENV
+      ret = up_addrenv_release(tcb);
+#endif
+
       /* And, finally, release the TCB itself */
 
       sched_free(tcb);