initial risc-v exampleHEADmaster

1 files changed, 117 insertions, 0 deletions

diff --git a/riscv/include/asm/thread_info.h b/riscv/include/asm/thread_info.h
new file mode 100644
index 0000000..f3301d8
--- /dev/null
+++ b/riscv/include/asm/thread_info.h
@@ -0,0 +1,117 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2009 Chen Liqin <liqin.chen@sunplusct.com>
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ */
+
+#ifndef _ASM_RISCV_THREAD_INFO_H
+#define _ASM_RISCV_THREAD_INFO_H
+
+#include <asm/page.h>
+//#include <linux/const.h>
+
+/* thread information allocation */
+#define THREAD_SIZE_ORDER	CONFIG_THREAD_SIZE_ORDER
+#define THREAD_SIZE		(PAGE_SIZE << THREAD_SIZE_ORDER)
+
+/*
+ * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
+ * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
+ * assembly.
+ */
+#ifdef CONFIG_VMAP_STACK
+#define THREAD_ALIGN            (2 * THREAD_SIZE)
+#else
+#define THREAD_ALIGN            THREAD_SIZE
+#endif
+
+#define THREAD_SHIFT            (PAGE_SHIFT + THREAD_SIZE_ORDER)
+#define OVERFLOW_STACK_SIZE     SZ_4K
+#define SHADOW_OVERFLOW_STACK_SIZE (1024)
+
+#define IRQ_STACK_SIZE		THREAD_SIZE
+
+#ifndef __ASSEMBLY__
+
+#include <asm/processor.h>
+#include <asm/csr.h>
+
+/*
+ * low level task data that entry.S needs immediate access to
+ * - this struct should fit entirely inside of one cache line
+ * - if the members of this struct changes, the assembly constants
+ *   in asm-offsets.c must be updated accordingly
+ * - thread_info is included in task_struct at an offset of 0.  This means that
+ *   tp points to both thread_info and task_struct.
+ */
+struct thread_info {
+	unsigned long		flags;		/* low level flags */
+	int                     preempt_count;  /* 0=>preemptible, <0=>BUG */
+	/*
+	 * These stack pointers are overwritten on every system call or
+	 * exception.  SP is also saved to the stack it can be recovered when
+	 * overwritten.
+	 */
+	long			kernel_sp;	/* Kernel stack pointer */
+	long			user_sp;	/* User stack pointer */
+	int			cpu;
+	unsigned long		syscall_work;	/* SYSCALL_WORK_ flags */
+#ifdef CONFIG_SHADOW_CALL_STACK
+	void			*scs_base;
+	void			*scs_sp;
+#endif
+};
+
+#ifdef CONFIG_SHADOW_CALL_STACK
+#define INIT_SCS							\
+	.scs_base	= init_shadow_call_stack,			\
+	.scs_sp		= init_shadow_call_stack,
+#else
+#define INIT_SCS
+#endif
+
+/*
+ * macros/functions for gaining access to the thread information structure
+ *
+ * preempt_count needs to be 1 initially, until the scheduler is functional.
+ */
+#define INIT_THREAD_INFO(tsk)			\
+{						\
+	.flags		= 0,			\
+	.preempt_count	= INIT_PREEMPT_COUNT,	\
+	INIT_SCS				\
+}
+
+void arch_release_task_struct(struct task_struct *tsk);
+int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
+
+#endif /* !__ASSEMBLY__ */
+
+/*
+ * thread information flags
+ * - these are process state flags that various assembly files may need to
+ *   access
+ * - pending work-to-be-done flags are in lowest half-word
+ * - other flags in upper half-word(s)
+ */
+#define TIF_NOTIFY_RESUME	1	/* callback before returning to user */
+#define TIF_SIGPENDING		2	/* signal pending */
+#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
+#define TIF_RESTORE_SIGMASK	4	/* restore signal mask in do_signal() */
+#define TIF_MEMDIE		5	/* is terminating due to OOM killer */
+#define TIF_NOTIFY_SIGNAL	9	/* signal notifications exist */
+#define TIF_UPROBE		10	/* uprobe breakpoint or singlestep */
+#define TIF_32BIT		11	/* compat-mode 32bit process */
+
+#define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
+#define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
+#define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
+#define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
+#define _TIF_UPROBE		(1 << TIF_UPROBE)
+
+#define _TIF_WORK_MASK \
+	(_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+	 _TIF_NOTIFY_SIGNAL | _TIF_UPROBE)
+
+#endif /* _ASM_RISCV_THREAD_INFO_H */