/****************************************************************************
* arch/z80/src/common/up_createstack.c
*
* Copyright (C) 2007-2009, 2013, 2015 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <sched.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/arch.h>
#include <nuttx/board.h>
#include "up_arch.h"
#include "up_internal.h"
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/****************************************************************************
* Global Functions
****************************************************************************/
/****************************************************************************
* Name: up_create_stack
*
* Description:
* Allocate a stack for a new thread and setup up stack-related information
* in the TCB.
*
* The following TCB fields must be initialized by this function:
*
* - adj_stack_size: Stack size after adjustment for hardware, processor,
* etc. This value is retained only for debug purposes.
* - stack_alloc_ptr: Pointer to allocated stack
* - adj_stack_ptr: Adjusted stack_alloc_ptr for HW. The initial value of
* the stack pointer.
*
* Inputs:
* - tcb: The TCB of new task
* - stack_size: The requested stack size. At least this much
* must be allocated.
* - ttype: The thread type. This may be one of following (defined in
* include/nuttx/sched.h):
*
* TCB_FLAG_TTYPE_TASK Normal user task
* TCB_FLAG_TTYPE_PTHREAD User pthread
* TCB_FLAG_TTYPE_KERNEL Kernel thread
*
* This thread type is normally available in the flags field of the TCB,
* however, there are certain contexts where the TCB may not be fully
* initialized when up_create_stack is called.
*
* If CONFIG_BUILD_KERNEL is defined, then this thread type may affect
* how the stack is allocated. For example, kernel thread stacks should
* be allocated from protected kernel memory. Stacks for user tasks and
* threads must come from memory that is accessible to user code.
*
****************************************************************************/
int up_create_stack(FAR struct tcb_s *tcb, size_t stack_size, uint8_t ttype)
{
/* Is there already a stack allocated of a different size? Because of
* alignment issues, stack_size might erroneously appear to be of a
* different size. Fortunately, this is not a critical operation.
*/
if (tcb->stack_alloc_ptr && tcb->adj_stack_size != stack_size)
{
/* Yes.. Release the old stack */
up_release_stack(tcb, ttype);
}
/* Do we need to allocate a new stack? */
if (!tcb->stack_alloc_ptr)
{
/* Allocate the stack. If DEBUG is enabled (but not stack debug),
* then create a zeroed stack to make stack dumps easier to trace.
*/
#if defined(CONFIG_BUILD_KERNEL) && defined(CONFIG_MM_KERNEL_HEAP)
/* Use the kernel allocator if this is a kernel thread */
if (ttype == TCB_FLAG_TTYPE_KERNEL)
{
tcb->stack_alloc_ptr = (uint32_t *)kmm_malloc(stack_size);
}
else
#endif
{
/* Use the user-space allocator if this is a task or pthread */
tcb->stack_alloc_ptr = (uint32_t *)kumm_malloc(stack_size);
}
#ifdef CONFIG_DEBUG
/* Was the allocation successful? */
if (!tcb->stack_alloc_ptr)
{
sdbg("ERROR: Failed to allocate stack, size %d\n", stack_size);
}
#endif
}
/* Did we successfully allocate a stack? */
if (tcb->stack_alloc_ptr)
{
size_t top_of_stack;
size_t size_of_stack;
/* Yes.. If stack debug is enabled, then fill the stack with a
* recognizable value that we can use later to test for high
* water marks.
*/
#ifdef CONFIG_STACK_COLORATION
memset(tcb->stack_alloc_ptr, 0xaa, stack_size);
#endif
/* The Z80 family uses a push-down stack: the stack grows
* toward loweraddresses in memory. The stack pointer
* register, points to the lowest, valid work address
* (the "top" of the stack). Items on the stack are
* referenced as positive word offsets from sp.
*/
top_of_stack = (uint32_t)tcb->stack_alloc_ptr + stack_size - 4;
/* The Z80 stack does not need to be aligned. Here is is aligned at
* word (4 byte) boundary.
*/
top_of_stack &= ~3;
size_of_stack = top_of_stack - (uint32_t)tcb->stack_alloc_ptr + 4;
/* Save the adjusted stack values in the struct tcb_s */
tcb->adj_stack_ptr = (uint32_t*)top_of_stack;
tcb->adj_stack_size = size_of_stack;
board_led_on(LED_STACKCREATED);
return OK;
}
return ERROR;
}
