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/***************************************************************************
* Copyright (c) 2024 Microsoft Corporation
* Copyright (c) 2026-present Eclipse ThreadX contributors
*
* This program and the accompanying materials are made available under the
* terms of the MIT License which is available at
* https://opensource.org/licenses/MIT.
*
* SPDX-License-Identifier: MIT
**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** ThreadX Component */
/** */
/** Thread */
/** */
/**************************************************************************/
/**************************************************************************/
#include "tx_api.h"
/* If TX_SINGLE_MODE_SECURE or TX_SINGLE_MODE_NON_SECURE is defined,
no secure stack functionality is needed. */
#if !defined(TX_SINGLE_MODE_SECURE) && !defined(TX_SINGLE_MODE_NON_SECURE)
#define TX_SOURCE_CODE
#include "cmsis_compiler.h" /* For intrinsic functions. */
#include "tx_secure_interface.h" /* Interface for NS code. */
/* Minimum size of secure stack. */
#ifndef TX_THREAD_SECURE_STACK_MINIMUM
#define TX_THREAD_SECURE_STACK_MINIMUM 256
#endif
/* Maximum size of secure stack. */
#ifndef TX_THREAD_SECURE_STACK_MAXIMUM
#define TX_THREAD_SECURE_STACK_MAXIMUM 1024
#endif
/* 8 bytes added to stack size to "seal" stack. */
#define TX_THREAD_STACK_SEAL_SIZE 8
#define TX_THREAD_STACK_SEAL_VALUE 0xFEF5EDA5
/* max number of Secure context */
#ifndef TX_MAX_SECURE_CONTEXTS
#define TX_MAX_SECURE_CONTEXTS 32
#endif
#define TX_INVALID_SECURE_CONTEXT_IDX (-1)
/* Secure stack info struct to hold stack start, stack limit,
current stack pointer, and pointer to owning thread.
This will be allocated for each thread with a secure stack. */
typedef struct TX_THREAD_SECURE_STACK_INFO_STRUCT
{
VOID *tx_thread_secure_stack_ptr; /* Thread's secure stack current pointer */
VOID *tx_thread_secure_stack_start; /* Thread's secure stack start address */
VOID *tx_thread_secure_stack_limit; /* Thread's secure stack limit */
TX_THREAD *tx_thread_ptr; /* Keep track of thread for error handling */
INT tx_next_free_index; /* Next free index of free secure context */
} TX_THREAD_SECURE_STACK_INFO;
/* Static secure contexts */
static TX_THREAD_SECURE_STACK_INFO tx_thread_secure_context[TX_MAX_SECURE_CONTEXTS];
/* Head of free secure context */
static INT tx_head_free_index = 0U;
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_thread_secure_mode_stack_initialize Cortex-Mxx/AC6 */
/* 6.1.10 */
/* AUTHOR */
/* */
/* Scott Larson, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function initializes secure mode to use PSP stack. */
/* */
/* INPUT */
/* */
/* None */
/* */
/* OUTPUT */
/* */
/* status */
/* */
/* CALLS */
/* */
/* __get_CONTROL Intrinsic to get CONTROL */
/* __set_CONTROL Intrinsic to set CONTROL */
/* __set_PSPLIM Intrinsic to set PSP limit */
/* __set_PSP Intrinsic to set PSP */
/* */
/* CALLED BY */
/* */
/* _tx_initialize_kernel_enter */
/* */
/**************************************************************************/
__attribute__((cmse_nonsecure_entry))
UINT _tx_thread_secure_mode_stack_initialize(void)
{
UINT status;
INT index;
/* Make sure function is called from interrupt (threads should not call). */
if (__get_IPSR() == 0)
{
status = TX_CALLER_ERROR;
}
else
{
/* Set secure mode to use PSP. */
__set_CONTROL(__get_CONTROL() | 2);
/* Set process stack pointer and stack limit to 0 to throw exception when a thread
without a secure stack calls a secure function that tries to use secure stack. */
__set_PSPLIM(0);
__set_PSP(0);
for (index = 0; index < TX_MAX_SECURE_CONTEXTS; index++)
{
/* Check last index and mark next free to invalid index */
if(index == (TX_MAX_SECURE_CONTEXTS - 1))
{
tx_thread_secure_context[index].tx_next_free_index = TX_INVALID_SECURE_CONTEXT_IDX;
}
else
{
tx_thread_secure_context[index].tx_next_free_index = index + 1;
}
}
status = TX_SUCCESS;
}
return status;
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_thread_secure_mode_stack_allocate Cortex-Mxx/AC6 */
/* 6.1.10 */
/* AUTHOR */
/* */
/* Scott Larson, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function allocates a thread's secure stack. */
/* */
/* INPUT */
/* */
/* thread_ptr Thread control block pointer */
/* stack_size Size of stack to allocates */
/* */
/* OUTPUT */
/* */
/* TX_THREAD_ERROR Invalid thread pointer */
/* TX_SIZE_ERROR Invalid stack size */
/* TX_CALLER_ERROR Invalid caller of function */
/* status Actual completion status */
/* */
/* CALLS */
/* */
/* __get_IPSR Intrinsic to get IPSR */
/* malloc Compiler's malloc function */
/* __set_PSPLIM Intrinsic to set PSP limit */
/* __set_PSP Intrinsic to set PSP */
/* __TZ_get_PSPLIM_NS Intrinsic to get NS PSP */
/* */
/* CALLED BY */
/* */
/* SVC Handler */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 09-30-2020 Scott Larson Initial Version 6.1 */
/* 10-16-2020 Scott Larson Modified comment(s), */
/* added stack sealing, */
/* resulting in version 6.1.1 */
/* 01-31-2022 Himanshu Gupta Modified comments(s), updated */
/* secure stack allocation, */
/* resulting in version 6.1.10 */
/* */
/**************************************************************************/
__attribute__((cmse_nonsecure_entry))
UINT _tx_thread_secure_mode_stack_allocate(TX_THREAD *thread_ptr, ULONG stack_size)
{
TX_INTERRUPT_SAVE_AREA
UINT status;
TX_THREAD_SECURE_STACK_INFO *info_ptr;
UCHAR *stack_mem;
INT secure_context_index;
status = TX_SUCCESS;
/* Make sure function is called from interrupt (threads should not call). */
if (__get_IPSR() == 0)
{
status = TX_CALLER_ERROR;
}
else if (stack_size < TX_THREAD_SECURE_STACK_MINIMUM || stack_size > TX_THREAD_SECURE_STACK_MAXIMUM)
{
status = TX_SIZE_ERROR;
}
/* Check if thread already has secure stack allocated. */
else if (thread_ptr -> tx_thread_secure_stack_context != 0)
{
status = TX_THREAD_ERROR;
}
else
{
TX_DISABLE
/* Allocate free index for secure stack info. */
if(tx_head_free_index != TX_INVALID_SECURE_CONTEXT_IDX)
{
secure_context_index = tx_head_free_index;
tx_head_free_index = tx_thread_secure_context[tx_head_free_index].tx_next_free_index;
tx_thread_secure_context[secure_context_index].tx_next_free_index = TX_INVALID_SECURE_CONTEXT_IDX;
}
else
{
secure_context_index = TX_INVALID_SECURE_CONTEXT_IDX;
}
TX_RESTORE
if(secure_context_index != TX_INVALID_SECURE_CONTEXT_IDX)
{
info_ptr = &tx_thread_secure_context[secure_context_index];
/* If stack info allocated, allocate a stack & seal. */
stack_mem = malloc(stack_size + TX_THREAD_STACK_SEAL_SIZE);
if(stack_mem != TX_NULL)
{
/* Secure stack has been allocated, save in the stack info struct. */
info_ptr -> tx_thread_secure_stack_limit = stack_mem;
info_ptr -> tx_thread_secure_stack_start = stack_mem + stack_size;
info_ptr -> tx_thread_secure_stack_ptr = info_ptr -> tx_thread_secure_stack_start;
info_ptr -> tx_thread_ptr = thread_ptr;
/* Seal bottom of stack. */
*(ULONG*)info_ptr -> tx_thread_secure_stack_start = TX_THREAD_STACK_SEAL_VALUE;
/* Save secure context id (i.e non-zero base index) in thread. */
thread_ptr -> tx_thread_secure_stack_context = (VOID *)(secure_context_index + 1);
/* Check if this thread is running by looking at its stack start and PSPLIM_NS */
if(((ULONG) thread_ptr -> tx_thread_stack_start & 0xFFFFFFF8) == __TZ_get_PSPLIM_NS())
{
/* If this thread is running, set Secure PSP and PSPLIM. */
__set_PSPLIM((ULONG)(info_ptr -> tx_thread_secure_stack_limit));
__set_PSP((ULONG)(info_ptr -> tx_thread_secure_stack_ptr));
}
}
else
{
TX_DISABLE
/* Stack not allocated, free the info struct. */
tx_thread_secure_context[secure_context_index].tx_next_free_index = tx_head_free_index;
tx_head_free_index = secure_context_index;
TX_RESTORE
status = TX_NO_MEMORY;
}
}
else
{
status = TX_NO_MEMORY;
}
}
return(status);
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_thread_secure_mode_stack_free Cortex-Mxx/AC6 */
/* 6.1.10 */
/* AUTHOR */
/* */
/* Scott Larson, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function frees a thread's secure stack. */
/* */
/* INPUT */
/* */
/* thread_ptr Thread control block pointer */
/* */
/* OUTPUT */
/* */
/* TX_THREAD_ERROR Invalid thread pointer */
/* TX_CALLER_ERROR Invalid caller of function */
/* status Actual completion status */
/* */
/* CALLS */
/* */
/* __get_IPSR Intrinsic to get IPSR */
/* free Compiler's free() function */
/* */
/* CALLED BY */
/* */
/* SVC Handler */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 09-30-2020 Scott Larson Initial Version 6.1 */
/* 10-16-2020 Scott Larson Modified comment(s), */
/* resulting in version 6.1.1 */
/* 01-31-2022 Himanshu Gupta Modified comments(s), updated */
/* secure stack allocation, */
/* resulting in version 6.1.10 */
/* */
/**************************************************************************/
__attribute__((cmse_nonsecure_entry))
UINT _tx_thread_secure_mode_stack_free(TX_THREAD *thread_ptr)
{
TX_INTERRUPT_SAVE_AREA
UINT status;
TX_THREAD_SECURE_STACK_INFO *info_ptr;
INT secure_context_index;
status = TX_SUCCESS;
/* Pickup stack info id from thread. */
secure_context_index = (INT)thread_ptr -> tx_thread_secure_stack_context - 1;
/* Make sure function is called from interrupt (threads should not call). */
if (__get_IPSR() == 0)
{
status = TX_CALLER_ERROR;
}
/* Check if secure context index is in valid range. */
else if (secure_context_index < 0 || secure_context_index >= TX_MAX_SECURE_CONTEXTS)
{
status = TX_THREAD_ERROR;
}
else
{
/* Pickup stack info from static array of secure contexts. */
info_ptr = &tx_thread_secure_context[secure_context_index];
/* Check that this secure context is for this thread. */
if (info_ptr -> tx_thread_ptr != thread_ptr)
{
status = TX_THREAD_ERROR;
}
else
{
/* Free secure stack. */
free(info_ptr -> tx_thread_secure_stack_limit);
TX_DISABLE
/* Free info struct. */
tx_thread_secure_context[secure_context_index].tx_next_free_index = tx_head_free_index;
tx_head_free_index = secure_context_index;
TX_RESTORE
/* Clear secure context from thread. */
thread_ptr -> tx_thread_secure_stack_context = 0;
}
}
return(status);
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_thread_secure_stack_context_save Cortex-Mxx/AC6 */
/* 6.1.10 */
/* AUTHOR */
/* */
/* Scott Larson, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function saves context of the secure stack. */
/* */
/* INPUT */
/* */
/* thread_ptr Thread control block pointer */
/* */
/* OUTPUT */
/* */
/* None */
/* */
/* CALLS */
/* */
/* __get_IPSR Intrinsic to get IPSR */
/* __get_PSP Intrinsic to get PSP */
/* __set_PSPLIM Intrinsic to set PSP limit */
/* __set_PSP Intrinsic to set PSP */
/* */
/* CALLED BY */
/* */
/* PendSV Handler */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 09-30-2020 Scott Larson Initial Version 6.1 */
/* 10-16-2020 Scott Larson Modified comment(s), */
/* resulting in version 6.1.1 */
/* 06-02-2021 Scott Larson Fix stack pointer save, */
/* resulting in version 6.1.7 */
/* 01-31-2022 Himanshu Gupta Modified comments(s), updated */
/* secure stack allocation, */
/* resulting in version 6.1.10 */
/* */
/**************************************************************************/
__attribute__((cmse_nonsecure_entry))
void _tx_thread_secure_stack_context_save(TX_THREAD *thread_ptr)
{
TX_THREAD_SECURE_STACK_INFO *info_ptr;
ULONG sp;
INT secure_context_index = (INT)thread_ptr -> tx_thread_secure_stack_context - 1;
/* This function should be called from scheduler only. */
if (__get_IPSR() == 0)
{
return;
}
/* Check if secure context index is in valid range. */
else if (secure_context_index < 0 || secure_context_index >= TX_MAX_SECURE_CONTEXTS)
{
return;
}
/* Pickup the secure context pointer. */
info_ptr = &tx_thread_secure_context[secure_context_index];
/* Check that this secure context is for this thread. */
if (info_ptr -> tx_thread_ptr != thread_ptr)
{
return;
}
/* Check that stack pointer is in range */
sp = __get_PSP();
if ((sp < (ULONG)info_ptr -> tx_thread_secure_stack_limit) ||
(sp > (ULONG)info_ptr -> tx_thread_secure_stack_start))
{
return;
}
/* Save stack pointer. */
info_ptr -> tx_thread_secure_stack_ptr = (VOID *) sp;
/* Set process stack pointer and stack limit to 0 to throw exception when a thread
without a secure stack calls a secure function that tries to use secure stack. */
__set_PSPLIM(0);
__set_PSP(0);
return;
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _tx_thread_secure_stack_context_restore Cortex-Mxx/AC6 */
/* 6.1.10 */
/* AUTHOR */
/* */
/* Scott Larson, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function restores context of the secure stack. */
/* */
/* INPUT */
/* */
/* thread_ptr Thread control block pointer */
/* */
/* OUTPUT */
/* */
/* None */
/* */
/* CALLS */
/* */
/* __get_IPSR Intrinsic to get IPSR */
/* __set_PSPLIM Intrinsic to set PSP limit */
/* __set_PSP Intrinsic to set PSP */
/* */
/* CALLED BY */
/* */
/* PendSV Handler */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 09-30-2020 Scott Larson Initial Version 6.1 */
/* 10-16-2020 Scott Larson Modified comment(s), */
/* resulting in version 6.1.1 */
/* 01-31-2022 Himanshu Gupta Modified comments(s), updated */
/* secure stack allocation, */
/* resulting in version 6.1.10 */
/* */
/**************************************************************************/
__attribute__((cmse_nonsecure_entry))
void _tx_thread_secure_stack_context_restore(TX_THREAD *thread_ptr)
{
TX_THREAD_SECURE_STACK_INFO *info_ptr;
INT secure_context_index = (INT)thread_ptr -> tx_thread_secure_stack_context - 1;
/* This function should be called from scheduler only. */
if (__get_IPSR() == 0)
{
return;
}
/* Check if secure context index is in valid range. */
else if (secure_context_index < 0 || secure_context_index >= TX_MAX_SECURE_CONTEXTS)
{
return;
}
/* Pickup the secure context pointer. */
info_ptr = &tx_thread_secure_context[secure_context_index];
/* Check that this secure context is for this thread. */
if (info_ptr -> tx_thread_ptr != thread_ptr)
{
return;
}
/* Set stack pointer and limit. */
__set_PSPLIM((ULONG)info_ptr -> tx_thread_secure_stack_limit);
__set_PSP ((ULONG)info_ptr -> tx_thread_secure_stack_ptr);
return;
}
#endif
|
