xtensa: userspace: Stack object header

Add a header with architecture specific macros and
definitions that re used on userspace for stack
objects.

Signed-off-by: Flavio Ceolin <[email protected]>

Author: Flavio Ceolin

include/zephyr/arch/xtensa/arch.h

@@ -29,16 +29,11 @@
 #include <zephyr/arch/common/addr_types.h>
 #include <zephyr/arch/xtensa/gdbstub.h>
 #include <zephyr/debug/sparse.h>
+#include <zephyr/arch/xtensa/thread_stack.h>
 #include <zephyr/sys/slist.h>
 
 #include <zephyr/arch/xtensa/xtensa_mmu.h>
 
-#ifdef CONFIG_KERNEL_COHERENCE
-#define ARCH_STACK_PTR_ALIGN XCHAL_DCACHE_LINESIZE
-#else
-#define ARCH_STACK_PTR_ALIGN 16
-#endif
-
 /* Xtensa GPRs are often designated by two different names */
 #define sys_define_gpr_with_alias(name1, name2) union { uint32_t name1, name2; }
 

include/zephyr/arch/xtensa/thread_stack.h

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2022 Intel Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_INCLUDE_ARCH_XTENSA_THREAD_STACK_H_
+#define ZEPHYR_INCLUDE_ARCH_XTENSA_THREAD_STACK_H_
+
+#include <xtensa/config/core-isa.h>
+#include <zephyr/toolchain.h>
+
+#ifdef CONFIG_KERNEL_COHERENCE
+#define ARCH_STACK_PTR_ALIGN XCHAL_DCACHE_LINESIZE
+#else
+#define ARCH_STACK_PTR_ALIGN 16
+#endif
+
+
+#if CONFIG_USERSPACE
+#define Z_XTENSA_STACK_BASE_ALIGN		CONFIG_MMU_PAGE_SIZE
+#define Z_XTENSA_STACK_SIZE_ALIGN		CONFIG_MMU_PAGE_SIZE
+#else
+#define Z_XTENSA_STACK_BASE_ALIGN		ARCH_STACK_PTR_ALIGN
+#define Z_XTENSA_STACK_SIZE_ALIGN		ARCH_STACK_PTR_ALIGN
+#endif
+
+/*
+ *
+ * High memory addresses
+ *
+ * +-------------------+ <- thread.stack_info.start + thread.stack_info.size
+ * |       TLS         |
+ * +-------------------+ <- initial sp (computable with thread.stack_info.delta)
+ * |                   |
+ * |   Thread stack    |
+ * |                   |
+ * +-------------------+ <- thread.stack_info.start
+ * | Privileged stack  | } CONFIG_MMU_PAGE_SIZE
+ * +-------------------+ <- thread.stack_obj
+ *
+ * Low Memory addresses
+ */
+
+#ifndef _ASMLANGUAGE
+
+/* thread stack */
+#ifdef CONFIG_XTENSA_MMU
+struct z_xtensa_thread_stack_header {
+	char privilege_stack[CONFIG_MMU_PAGE_SIZE];
+} __packed __aligned(Z_XTENSA_STACK_BASE_ALIGN);
+
+#define ARCH_THREAD_STACK_RESERVED		\
+	sizeof(struct z_xtensa_thread_stack_header)
+#endif /* CONFIG_XTENSA_MMU */
+
+#define ARCH_THREAD_STACK_OBJ_ALIGN(size)	Z_XTENSA_STACK_BASE_ALIGN
+#define ARCH_THREAD_STACK_SIZE_ADJUST(size)	\
+	ROUND_UP((size), Z_XTENSA_STACK_SIZE_ALIGN)
+
+/* kernel stack */
+#define ARCH_KERNEL_STACK_RESERVED		0
+#define ARCH_KERNEL_STACK_OBJ_ALIGN		ARCH_STACK_PTR_ALIGN
+
+#endif /* _ASMLANGUAGE */
+
+#endif