unicore32 additional architecture files: low-level lib: misc

This patch implements the rest low-level libraries.

Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 143 insertions, 0 deletions

diff --git a/arch/unicore32/include/asm/futex.h b/arch/unicore32/include/asm/futex.h
new file mode 100644
index 00000000000..07dea617055
--- /dev/null
+++ b/arch/unicore32/include/asm/futex.h
@@ -0,0 +1,143 @@
+/*
+ * linux/arch/unicore32/include/asm/futex.h
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __UNICORE_FUTEX_H__
+#define __UNICORE_FUTEX_H__
+
+#ifdef __KERNEL__
+
+#include <linux/futex.h>
+#include <linux/preempt.h>
+#include <linux/uaccess.h>
+#include <linux/errno.h>
+
+#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg)      \
+        __asm__ __volatile__(                                   \
+        "1:     ldw.u   %1, [%2]\n"                             \
+        "       " insn "\n"                                     \
+        "2:     stw.u   %0, [%2]\n"                             \
+        "       mov     %0, #0\n"                               \
+        "3:\n"                                                  \
+        "       .pushsection __ex_table,\"a\"\n"                \
+        "       .align  3\n"                                    \
+        "       .long   1b, 4f, 2b, 4f\n"                       \
+        "       .popsection\n"                                  \
+        "       .pushsection .fixup,\"ax\"\n"                   \
+        "4:     mov     %0, %4\n"                               \
+        "       b       3b\n"                                   \
+        "       .popsection"                                    \
+        : "=&r" (ret), "=&r" (oldval)                           \
+        : "r" (uaddr), "r" (oparg), "Ir" (-EFAULT)              \
+        : "cc", "memory")
+
+static inline int
+futex_atomic_op_inuser(int encoded_op, int __user *uaddr)
+{
+        int op = (encoded_op >> 28) & 7;
+        int cmp = (encoded_op >> 24) & 15;
+        int oparg = (encoded_op << 8) >> 20;
+        int cmparg = (encoded_op << 20) >> 20;
+        int oldval = 0, ret;
+
+        if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
+                oparg = 1 << oparg;
+
+        if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+                return -EFAULT;
+
+        pagefault_disable();    /* implies preempt_disable() */
+
+        switch (op) {
+        case FUTEX_OP_SET:
+                __futex_atomic_op("mov  %0, %3", ret, oldval, uaddr, oparg);
+                break;
+        case FUTEX_OP_ADD:
+                __futex_atomic_op("add  %0, %1, %3", ret, oldval, uaddr, oparg);
+                break;
+        case FUTEX_OP_OR:
+                __futex_atomic_op("or   %0, %1, %3", ret, oldval, uaddr, oparg);
+                break;
+        case FUTEX_OP_ANDN:
+                __futex_atomic_op("and  %0, %1, %3",
+                                ret, oldval, uaddr, ~oparg);
+                break;
+        case FUTEX_OP_XOR:
+                __futex_atomic_op("xor  %0, %1, %3", ret, oldval, uaddr, oparg);
+                break;
+        default:
+                ret = -ENOSYS;
+        }
+
+        pagefault_enable();     /* subsumes preempt_enable() */
+
+        if (!ret) {
+                switch (cmp) {
+                case FUTEX_OP_CMP_EQ:
+                        ret = (oldval == cmparg);
+                        break;
+                case FUTEX_OP_CMP_NE:
+                        ret = (oldval != cmparg);
+                        break;
+                case FUTEX_OP_CMP_LT:
+                        ret = (oldval <  cmparg);
+                        break;
+                case FUTEX_OP_CMP_GE:
+                        ret = (oldval >= cmparg);
+                        break;
+                case FUTEX_OP_CMP_LE:
+                        ret = (oldval <= cmparg);
+                        break;
+                case FUTEX_OP_CMP_GT:
+                        ret = (oldval >  cmparg);
+                        break;
+                default:
+                        ret = -ENOSYS;
+                }
+        }
+        return ret;
+}
+
+static inline int
+futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
+{
+        int val;
+
+        if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+                return -EFAULT;
+
+        pagefault_disable();    /* implies preempt_disable() */
+
+        __asm__ __volatile__("@futex_atomic_cmpxchg_inatomic\n"
+        "1:     ldw.u   %0, [%3]\n"
+        "       cmpxor.a        %0, %1\n"
+        "       bne     3f\n"
+        "2:     stw.u   %2, [%3]\n"
+        "3:\n"
+        "       .pushsection __ex_table,\"a\"\n"
+        "       .align  3\n"
+        "       .long   1b, 4f, 2b, 4f\n"
+        "       .popsection\n"
+        "       .pushsection .fixup,\"ax\"\n"
+        "4:     mov     %0, %4\n"
+        "       b       3b\n"
+        "       .popsection"
+        : "=&r" (val)
+        : "r" (oldval), "r" (newval), "r" (uaddr), "Ir" (-EFAULT)
+        : "cc", "memory");
+
+        pagefault_enable();     /* subsumes preempt_enable() */
+
+        return val;
+}
+
+#endif /* __KERNEL__ */
+#endif /* __UNICORE_FUTEX_H__ */