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-rw-r--r--arch/riscv/include/asm/processor.h97
1 files changed, 97 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
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+++ b/arch/riscv/include/asm/processor.h
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PROCESSOR_H
+#define _ASM_RISCV_PROCESSOR_H
+
+#include <linux/const.h>
+
+#include <asm/ptrace.h>
+
+/*
+ * This decides where the kernel will search for a free chunk of vm
+ * space during mmap's.
+ */
+#define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE >> 1)
+
+#define STACK_TOP TASK_SIZE
+#define STACK_TOP_MAX STACK_TOP
+#define STACK_ALIGN 16
+
+#ifndef __ASSEMBLY__
+
+struct task_struct;
+struct pt_regs;
+
+/*
+ * Default implementation of macro that returns current
+ * instruction pointer ("program counter").
+ */
+#define current_text_addr() ({ __label__ _l; _l: &&_l; })
+
+/* CPU-specific state of a task */
+struct thread_struct {
+ /* Callee-saved registers */
+ unsigned long ra;
+ unsigned long sp; /* Kernel mode stack */
+ unsigned long s[12]; /* s[0]: frame pointer */
+ struct __riscv_d_ext_state fstate;
+};
+
+#define INIT_THREAD { \
+ .sp = sizeof(init_stack) + (long)&init_stack, \
+}
+
+#define task_pt_regs(tsk) \
+ ((struct pt_regs *)(task_stack_page(tsk) + THREAD_SIZE \
+ - ALIGN(sizeof(struct pt_regs), STACK_ALIGN)))
+
+#define KSTK_EIP(tsk) (task_pt_regs(tsk)->sepc)
+#define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp)
+
+
+/* Do necessary setup to start up a newly executed thread. */
+extern void start_thread(struct pt_regs *regs,
+ unsigned long pc, unsigned long sp);
+
+/* Free all resources held by a thread. */
+static inline void release_thread(struct task_struct *dead_task)
+{
+}
+
+extern unsigned long get_wchan(struct task_struct *p);
+
+
+static inline void cpu_relax(void)
+{
+#ifdef __riscv_muldiv
+ int dummy;
+ /* In lieu of a halt instruction, induce a long-latency stall. */
+ __asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy));
+#endif
+ barrier();
+}
+
+static inline void wait_for_interrupt(void)
+{
+ __asm__ __volatile__ ("wfi");
+}
+
+struct device_node;
+extern int riscv_of_processor_hart(struct device_node *node);
+
+extern void riscv_fill_hwcap(void);
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_PROCESSOR_H */