Implement vfork() for the MIPS32 architecture

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5520 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 132 insertions, 0 deletions

diff --git a/nuttx/arch/mips/src/mips32/up_vfork.h b/nuttx/arch/mips/src/mips32/up_vfork.h
new file mode 100644
index 000000000..556633072
--- /dev/null
+++ b/nuttx/arch/mips/src/mips32/up_vfork.h
@@ -0,0 +1,132 @@
+/****************************************************************************
+ * arch/mips/src/mips/up_vfork.h
+ *
+ *   Copyright (C) 2013 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 __ARCH_MIPS_SRC_MIPS32_VFORK_H
+#define __ARCH_MIPS_SRC_MIPS32_VFORK_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <arch/mips32/irq.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+/* Register r30 may be a frame pointer in some ABIs.  Or may just be saved
+ * register s8.  It makes a difference for vfork handling.
+ */
+
+#undef VFORK_HAVE_FP
+
+/* r0      zero   Always has the value 0.
+ * r1      at     Temporary generally used by assembler.
+ * r2-r3   v0-v1  Used for expression evaluations and to hold the integer and
+ *                pointer type function return values.
+ * r4-r7   a0-a3  Used for passing arguments to functions; values are not
+ *                preserved across function calls.
+ * r8-r15  t0-t7  Temporary registers used for expression evaluation; values
+ *                are not preserved across function calls.
+ * r16-r23 s0-s7  Saved registers; values are preserved across function calls.
+ * r24-r25 t8-t9  Temporary registers used for expression evaluations; values
+ *                are not preserved across function calls. When calling
+ *                position independent functions r25 must contain the address
+ *                of the called function.
+ * r26-r27 k0-k1  Used only by the operating system.
+ * r28     gp     Global pointer and context pointer.
+ * r29     sp     Stack pointer.
+ * r30     s8     Saved register (like s0-s7).  If a frame pointer is used,
+ *                then this is the frame pointer.
+ * r31     ra     Return address.
+ */
+ 
+#define VFORK_S0_OFFSET   (0*4)   /* Saved register s0 */
+#define VFORK_S1_OFFSET   (1*4)   /* Saved register s1 */
+#define VFORK_S2_OFFSET   (2*4)   /* Saved register s2 */
+#define VFORK_S3_OFFSET   (3*4)   /* Saved register s3 */
+#define VFORK_S4_OFFSET   (4*4)   /* Saved register s4 */
+#define VFORK_S5_OFFSET   (5*4)   /* Saved register s5 */
+#define VFORK_S6_OFFSET   (6*4)   /* Saved register s6 */
+#define VFORK_S7_OFFSET   (7*4)   /* Saved register s7 */
+
+#ifdef CONFIG_MIPS32_FRAMEPOINTER
+#  define VFORK_FP_OFFSET (8*4)   /* Frame pointer */
+#else
+#  define VFORK_S8_OFFSET (8*4)   /* Saved register s8 */
+#endif
+
+#define VFORK_SP_OFFSET   (9*4)   /* Stack pointer*/
+#define VFORK_RA_OFFSET   (10*4)  /* Return address*/
+#ifdef MIPS32_SAVE_GP
+#  define VFORK_GP_OFFSET (11*4)   /* Global pointer */
+#  define VFORK_SIZEOF    (12*4)
+#else
+#  define VFORK_SIZEOF    (11*4)
+#endif
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+#ifndef __ASSEMBLY__
+struct vfork_s
+{
+  /* CPU registers */
+
+  uint32_t s0;   /* Saved register s0 */
+  uint32_t s1;   /* Saved register s1 */
+  uint32_t s2;   /* Saved register s2 */
+  uint32_t s3;   /* Saved register s3 */
+  uint32_t s4;   /* Saved register s4 */
+  uint32_t s5;   /* Saved register s5 */
+  uint32_t s6;   /* Saved register s6 */
+  uint32_t s7;   /* Saved register s7 */
+#ifdef CONFIG_MIPS32_FRAMEPOINTER
+  uint32_t fp;   /* Frame pointer */
+#else
+  uint32_t s8;   /* Saved register s8 */
+#endif
+  uint32_t sp;   /* Stack pointer*/
+  uint32_t ra;   /* Return address*/
+#ifdef MIPS32_SAVE_GP
+  uint32_t gp;   /* Global pointer */
+#endif
+
+  /* Floating point registers (not yet) */
+};
+#endif
+
+#endif /* __ARCH_MIPS_SRC_MIPS32_VFORK_H */