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-rw-r--r--arch/arm/include/asm/tls.h63
1 files changed, 63 insertions, 0 deletions
diff --git a/arch/arm/include/asm/tls.h b/arch/arm/include/asm/tls.h
new file mode 100644
index 00000000000..83259b87333
--- /dev/null
+++ b/arch/arm/include/asm/tls.h
@@ -0,0 +1,63 @@
+#ifndef __ASMARM_TLS_H
+#define __ASMARM_TLS_H
+
+#ifdef __ASSEMBLY__
+#include <asm/asm-offsets.h>
+ .macro switch_tls_none, base, tp, tpuser, tmp1, tmp2
+ .endm
+
+ .macro switch_tls_v6k, base, tp, tpuser, tmp1, tmp2
+ mrc p15, 0, \tmp2, c13, c0, 2 @ get the user r/w register
+ mcr p15, 0, \tp, c13, c0, 3 @ set TLS register
+ mcr p15, 0, \tpuser, c13, c0, 2 @ and the user r/w register
+ str \tmp2, [\base, #TI_TP_VALUE + 4] @ save it
+ .endm
+
+ .macro switch_tls_v6, base, tp, tpuser, tmp1, tmp2
+ ldr \tmp1, =elf_hwcap
+ ldr \tmp1, [\tmp1, #0]
+ mov \tmp2, #0xffff0fff
+ tst \tmp1, #HWCAP_TLS @ hardware TLS available?
+ streq \tp, [\tmp2, #-15] @ set TLS value at 0xffff0ff0
+ mrcne p15, 0, \tmp2, c13, c0, 2 @ get the user r/w register
+ mcrne p15, 0, \tp, c13, c0, 3 @ yes, set TLS register
+ mcrne p15, 0, \tpuser, c13, c0, 2 @ set user r/w register
+ strne \tmp2, [\base, #TI_TP_VALUE + 4] @ save it
+ .endm
+
+ .macro switch_tls_software, base, tp, tpuser, tmp1, tmp2
+ mov \tmp1, #0xffff0fff
+ str \tp, [\tmp1, #-15] @ set TLS value at 0xffff0ff0
+ .endm
+#endif
+
+#ifdef CONFIG_TLS_REG_EMUL
+#define tls_emu 1
+#define has_tls_reg 1
+#define switch_tls switch_tls_none
+#elif defined(CONFIG_CPU_V6)
+#define tls_emu 0
+#define has_tls_reg (elf_hwcap & HWCAP_TLS)
+#define switch_tls switch_tls_v6
+#elif defined(CONFIG_CPU_32v6K)
+#define tls_emu 0
+#define has_tls_reg 1
+#define switch_tls switch_tls_v6k
+#else
+#define tls_emu 0
+#define has_tls_reg 0
+#define switch_tls switch_tls_software
+#endif
+
+#ifndef __ASSEMBLY__
+static inline unsigned long get_tpuser(void)
+{
+ unsigned long reg = 0;
+
+ if (has_tls_reg && !tls_emu)
+ __asm__("mrc p15, 0, %0, c13, c0, 2" : "=r" (reg));
+
+ return reg;
+}
+#endif
+#endif /* __ASMARM_TLS_H */