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authorLeonid Yegoshin <Leonid.Yegoshin@imgtec.com>2014-10-28 11:42:23 +0100
committerMarkos Chandras <markos.chandras@imgtec.com>2015-02-17 16:37:28 +0100
commit0593a44c6403d0b2afdac94a261ad474719e8322 (patch)
treed34136c29668c6ab03bd9ea29e8781b615803503 /arch
parentMIPS: kernel: cps-vec: Replace "addi" with "addiu" (diff)
downloadlinux-0593a44c6403d0b2afdac94a261ad474719e8322.tar.xz
linux-0593a44c6403d0b2afdac94a261ad474719e8322.zip
MIPS: kernel: unaligned: Add support for the MIPS R6
The load/store unaligned instructions have been removed in MIPS R6 so we need to re-implement the related macros using the regular load/store instructions. Moreover, the load/store from coprocessor 2 instructions have been reallocated in Release 6 so we will handle them in the emulator instead. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/mips/kernel/unaligned.c390
1 files changed, 386 insertions, 4 deletions
diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c
index e11906dff885..bbb69695a0a1 100644
--- a/arch/mips/kernel/unaligned.c
+++ b/arch/mips/kernel/unaligned.c
@@ -129,6 +129,7 @@ extern void show_registers(struct pt_regs *regs);
: "=&r" (value), "=r" (res) \
: "r" (addr), "i" (-EFAULT));
+#ifndef CONFIG_CPU_MIPSR6
#define LoadW(addr, value, res) \
__asm__ __volatile__ ( \
"1:\t"user_lwl("%0", "(%2)")"\n" \
@@ -146,6 +147,39 @@ extern void show_registers(struct pt_regs *regs);
".previous" \
: "=&r" (value), "=r" (res) \
: "r" (addr), "i" (-EFAULT));
+#else
+/* MIPSR6 has no lwl instruction */
+#define LoadW(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n" \
+ ".set\tnoat\n\t" \
+ "1:"user_lb("%0", "0(%2)")"\n\t" \
+ "2:"user_lbu("$1", "1(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "3:"user_lbu("$1", "2(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "4:"user_lbu("$1", "3(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "li\t%1, 0\n" \
+ ".set\tpop\n" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%1, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (value), "=r" (res) \
+ : "r" (addr), "i" (-EFAULT));
+#endif /* CONFIG_CPU_MIPSR6 */
#define LoadHWU(addr, value, res) \
__asm__ __volatile__ ( \
@@ -169,6 +203,7 @@ extern void show_registers(struct pt_regs *regs);
: "=&r" (value), "=r" (res) \
: "r" (addr), "i" (-EFAULT));
+#ifndef CONFIG_CPU_MIPSR6
#define LoadWU(addr, value, res) \
__asm__ __volatile__ ( \
"1:\t"user_lwl("%0", "(%2)")"\n" \
@@ -206,6 +241,87 @@ extern void show_registers(struct pt_regs *regs);
".previous" \
: "=&r" (value), "=r" (res) \
: "r" (addr), "i" (-EFAULT));
+#else
+/* MIPSR6 has not lwl and ldl instructions */
+#define LoadWU(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n\t" \
+ ".set\tnoat\n\t" \
+ "1:"user_lbu("%0", "0(%2)")"\n\t" \
+ "2:"user_lbu("$1", "1(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "3:"user_lbu("$1", "2(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "4:"user_lbu("$1", "3(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "li\t%1, 0\n" \
+ ".set\tpop\n" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%1, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (value), "=r" (res) \
+ : "r" (addr), "i" (-EFAULT));
+
+#define LoadDW(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n\t" \
+ ".set\tnoat\n\t" \
+ "1:lb\t%0, 0(%2)\n\t" \
+ "2:lbu\t $1, 1(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "3:lbu\t$1, 2(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "4:lbu\t$1, 3(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "5:lbu\t$1, 4(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "6:lbu\t$1, 5(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "7:lbu\t$1, 6(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "8:lbu\t$1, 7(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "li\t%1, 0\n" \
+ ".set\tpop\n\t" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%1, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ STR(PTR)"\t5b, 11b\n\t" \
+ STR(PTR)"\t6b, 11b\n\t" \
+ STR(PTR)"\t7b, 11b\n\t" \
+ STR(PTR)"\t8b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (value), "=r" (res) \
+ : "r" (addr), "i" (-EFAULT));
+#endif /* CONFIG_CPU_MIPSR6 */
+
#define StoreHW(addr, value, res) \
__asm__ __volatile__ ( \
@@ -228,6 +344,7 @@ extern void show_registers(struct pt_regs *regs);
: "=r" (res) \
: "r" (value), "r" (addr), "i" (-EFAULT));
+#ifndef CONFIG_CPU_MIPSR6
#define StoreW(addr, value, res) \
__asm__ __volatile__ ( \
"1:\t"user_swl("%1", "(%2)")"\n" \
@@ -263,9 +380,82 @@ extern void show_registers(struct pt_regs *regs);
".previous" \
: "=r" (res) \
: "r" (value), "r" (addr), "i" (-EFAULT));
-#endif
+#else
+/* MIPSR6 has no swl and sdl instructions */
+#define StoreW(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n\t" \
+ ".set\tnoat\n\t" \
+ "1:"user_sb("%1", "3(%2)")"\n\t" \
+ "srl\t$1, %1, 0x8\n\t" \
+ "2:"user_sb("$1", "2(%2)")"\n\t" \
+ "srl\t$1, $1, 0x8\n\t" \
+ "3:"user_sb("$1", "1(%2)")"\n\t" \
+ "srl\t$1, $1, 0x8\n\t" \
+ "4:"user_sb("$1", "0(%2)")"\n\t" \
+ ".set\tpop\n\t" \
+ "li\t%0, 0\n" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%0, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (res) \
+ : "r" (value), "r" (addr), "i" (-EFAULT) \
+ : "memory");
+
+#define StoreDW(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n\t" \
+ ".set\tnoat\n\t" \
+ "1:sb\t%1, 7(%2)\n\t" \
+ "dsrl\t$1, %1, 0x8\n\t" \
+ "2:sb\t$1, 6(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "3:sb\t$1, 5(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "4:sb\t$1, 4(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "5:sb\t$1, 3(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "6:sb\t$1, 2(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "7:sb\t$1, 1(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "8:sb\t$1, 0(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ ".set\tpop\n\t" \
+ "li\t%0, 0\n" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%0, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ STR(PTR)"\t5b, 11b\n\t" \
+ STR(PTR)"\t6b, 11b\n\t" \
+ STR(PTR)"\t7b, 11b\n\t" \
+ STR(PTR)"\t8b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (res) \
+ : "r" (value), "r" (addr), "i" (-EFAULT) \
+ : "memory");
+#endif /* CONFIG_CPU_MIPSR6 */
+
+#else /* __BIG_ENDIAN */
-#ifdef __LITTLE_ENDIAN
#define LoadHW(addr, value, res) \
__asm__ __volatile__ (".set\tnoat\n" \
"1:\t"user_lb("%0", "1(%2)")"\n" \
@@ -286,6 +476,7 @@ extern void show_registers(struct pt_regs *regs);
: "=&r" (value), "=r" (res) \
: "r" (addr), "i" (-EFAULT));
+#ifndef CONFIG_CPU_MIPSR6
#define LoadW(addr, value, res) \
__asm__ __volatile__ ( \
"1:\t"user_lwl("%0", "3(%2)")"\n" \
@@ -303,6 +494,40 @@ extern void show_registers(struct pt_regs *regs);
".previous" \
: "=&r" (value), "=r" (res) \
: "r" (addr), "i" (-EFAULT));
+#else
+/* MIPSR6 has no lwl instruction */
+#define LoadW(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n" \
+ ".set\tnoat\n\t" \
+ "1:"user_lb("%0", "3(%2)")"\n\t" \
+ "2:"user_lbu("$1", "2(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "3:"user_lbu("$1", "1(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "4:"user_lbu("$1", "0(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "li\t%1, 0\n" \
+ ".set\tpop\n" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%1, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (value), "=r" (res) \
+ : "r" (addr), "i" (-EFAULT));
+#endif /* CONFIG_CPU_MIPSR6 */
+
#define LoadHWU(addr, value, res) \
__asm__ __volatile__ ( \
@@ -326,6 +551,7 @@ extern void show_registers(struct pt_regs *regs);
: "=&r" (value), "=r" (res) \
: "r" (addr), "i" (-EFAULT));
+#ifndef CONFIG_CPU_MIPSR6
#define LoadWU(addr, value, res) \
__asm__ __volatile__ ( \
"1:\t"user_lwl("%0", "3(%2)")"\n" \
@@ -363,6 +589,86 @@ extern void show_registers(struct pt_regs *regs);
".previous" \
: "=&r" (value), "=r" (res) \
: "r" (addr), "i" (-EFAULT));
+#else
+/* MIPSR6 has not lwl and ldl instructions */
+#define LoadWU(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n\t" \
+ ".set\tnoat\n\t" \
+ "1:"user_lbu("%0", "3(%2)")"\n\t" \
+ "2:"user_lbu("$1", "2(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "3:"user_lbu("$1", "1(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "4:"user_lbu("$1", "0(%2)")"\n\t" \
+ "sll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "li\t%1, 0\n" \
+ ".set\tpop\n" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%1, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (value), "=r" (res) \
+ : "r" (addr), "i" (-EFAULT));
+
+#define LoadDW(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n\t" \
+ ".set\tnoat\n\t" \
+ "1:lb\t%0, 7(%2)\n\t" \
+ "2:lbu\t$1, 6(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "3:lbu\t$1, 5(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "4:lbu\t$1, 4(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "5:lbu\t$1, 3(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "6:lbu\t$1, 2(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "7:lbu\t$1, 1(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "8:lbu\t$1, 0(%2)\n\t" \
+ "dsll\t%0, 0x8\n\t" \
+ "or\t%0, $1\n\t" \
+ "li\t%1, 0\n" \
+ ".set\tpop\n\t" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%1, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ STR(PTR)"\t5b, 11b\n\t" \
+ STR(PTR)"\t6b, 11b\n\t" \
+ STR(PTR)"\t7b, 11b\n\t" \
+ STR(PTR)"\t8b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (value), "=r" (res) \
+ : "r" (addr), "i" (-EFAULT));
+#endif /* CONFIG_CPU_MIPSR6 */
#define StoreHW(addr, value, res) \
__asm__ __volatile__ ( \
@@ -384,7 +690,7 @@ extern void show_registers(struct pt_regs *regs);
".previous" \
: "=r" (res) \
: "r" (value), "r" (addr), "i" (-EFAULT));
-
+#ifndef CONFIG_CPU_MIPSR6
#define StoreW(addr, value, res) \
__asm__ __volatile__ ( \
"1:\t"user_swl("%1", "3(%2)")"\n" \
@@ -420,6 +726,79 @@ extern void show_registers(struct pt_regs *regs);
".previous" \
: "=r" (res) \
: "r" (value), "r" (addr), "i" (-EFAULT));
+#else
+/* MIPSR6 has no swl and sdl instructions */
+#define StoreW(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n\t" \
+ ".set\tnoat\n\t" \
+ "1:"user_sb("%1", "0(%2)")"\n\t" \
+ "srl\t$1, %1, 0x8\n\t" \
+ "2:"user_sb("$1", "1(%2)")"\n\t" \
+ "srl\t$1, $1, 0x8\n\t" \
+ "3:"user_sb("$1", "2(%2)")"\n\t" \
+ "srl\t$1, $1, 0x8\n\t" \
+ "4:"user_sb("$1", "3(%2)")"\n\t" \
+ ".set\tpop\n\t" \
+ "li\t%0, 0\n" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%0, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (res) \
+ : "r" (value), "r" (addr), "i" (-EFAULT) \
+ : "memory");
+
+#define StoreDW(addr, value, res) \
+ __asm__ __volatile__ ( \
+ ".set\tpush\n\t" \
+ ".set\tnoat\n\t" \
+ "1:sb\t%1, 0(%2)\n\t" \
+ "dsrl\t$1, %1, 0x8\n\t" \
+ "2:sb\t$1, 1(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "3:sb\t$1, 2(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "4:sb\t$1, 3(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "5:sb\t$1, 4(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "6:sb\t$1, 5(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "7:sb\t$1, 6(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ "8:sb\t$1, 7(%2)\n\t" \
+ "dsrl\t$1, $1, 0x8\n\t" \
+ ".set\tpop\n\t" \
+ "li\t%0, 0\n" \
+ "10:\n\t" \
+ ".insn\n\t" \
+ ".section\t.fixup,\"ax\"\n\t" \
+ "11:\tli\t%0, %3\n\t" \
+ "j\t10b\n\t" \
+ ".previous\n\t" \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR)"\t1b, 11b\n\t" \
+ STR(PTR)"\t2b, 11b\n\t" \
+ STR(PTR)"\t3b, 11b\n\t" \
+ STR(PTR)"\t4b, 11b\n\t" \
+ STR(PTR)"\t5b, 11b\n\t" \
+ STR(PTR)"\t6b, 11b\n\t" \
+ STR(PTR)"\t7b, 11b\n\t" \
+ STR(PTR)"\t8b, 11b\n\t" \
+ ".previous" \
+ : "=&r" (res) \
+ : "r" (value), "r" (addr), "i" (-EFAULT) \
+ : "memory");
+#endif /* CONFIG_CPU_MIPSR6 */
#endif
static void emulate_load_store_insn(struct pt_regs *regs,
@@ -703,10 +1082,13 @@ static void emulate_load_store_insn(struct pt_regs *regs,
break;
return;
+#ifndef CONFIG_CPU_MIPSR6
/*
* COP2 is available to implementor for application specific use.
* It's up to applications to register a notifier chain and do
* whatever they have to do, including possible sending of signals.
+ *
+ * This instruction has been reallocated in Release 6
*/
case lwc2_op:
cu2_notifier_call_chain(CU2_LWC2_OP, regs);
@@ -723,7 +1105,7 @@ static void emulate_load_store_insn(struct pt_regs *regs,
case sdc2_op:
cu2_notifier_call_chain(CU2_SDC2_OP, regs);
break;
-
+#endif
default:
/*
* Pheeee... We encountered an yet unknown instruction or