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Diffstat (limited to 'arch/mips/kernel/jump_label.c')
-rw-r--r--arch/mips/kernel/jump_label.c42
1 files changed, 32 insertions, 10 deletions
diff --git a/arch/mips/kernel/jump_label.c b/arch/mips/kernel/jump_label.c
index 6001610cfe55..dda800e9e731 100644
--- a/arch/mips/kernel/jump_label.c
+++ b/arch/mips/kernel/jump_label.c
@@ -18,31 +18,53 @@
#ifdef HAVE_JUMP_LABEL
-#define J_RANGE_MASK ((1ul << 28) - 1)
+/*
+ * Define parameters for the standard MIPS and the microMIPS jump
+ * instruction encoding respectively:
+ *
+ * - the ISA bit of the target, either 0 or 1 respectively,
+ *
+ * - the amount the jump target address is shifted right to fit in the
+ * immediate field of the machine instruction, either 2 or 1,
+ *
+ * - the mask determining the size of the jump region relative to the
+ * delay-slot instruction, either 256MB or 128MB,
+ *
+ * - the jump target alignment, either 4 or 2 bytes.
+ */
+#define J_ISA_BIT IS_ENABLED(CONFIG_CPU_MICROMIPS)
+#define J_RANGE_SHIFT (2 - J_ISA_BIT)
+#define J_RANGE_MASK ((1ul << (26 + J_RANGE_SHIFT)) - 1)
+#define J_ALIGN_MASK ((1ul << J_RANGE_SHIFT) - 1)
void arch_jump_label_transform(struct jump_entry *e,
enum jump_label_type type)
{
+ union mips_instruction *insn_p;
union mips_instruction insn;
- union mips_instruction *insn_p =
- (union mips_instruction *)(unsigned long)e->code;
- /* Jump only works within a 256MB aligned region. */
- BUG_ON((e->target & ~J_RANGE_MASK) != (e->code & ~J_RANGE_MASK));
+ insn_p = (union mips_instruction *)msk_isa16_mode(e->code);
+
+ /* Jump only works within an aligned region its delay slot is in. */
+ BUG_ON((e->target & ~J_RANGE_MASK) != ((e->code + 4) & ~J_RANGE_MASK));
- /* Target must have 4 byte alignment. */
- BUG_ON((e->target & 3) != 0);
+ /* Target must have the right alignment and ISA must be preserved. */
+ BUG_ON((e->target & J_ALIGN_MASK) != J_ISA_BIT);
if (type == JUMP_LABEL_ENABLE) {
- insn.j_format.opcode = j_op;
- insn.j_format.target = (e->target & J_RANGE_MASK) >> 2;
+ insn.j_format.opcode = J_ISA_BIT ? mm_j32_op : j_op;
+ insn.j_format.target = e->target >> J_RANGE_SHIFT;
} else {
insn.word = 0; /* nop */
}
get_online_cpus();
mutex_lock(&text_mutex);
- *insn_p = insn;
+ if (IS_ENABLED(CONFIG_CPU_MICROMIPS)) {
+ insn_p->halfword[0] = insn.word >> 16;
+ insn_p->halfword[1] = insn.word;
+ } else
+ *insn_p = insn;
flush_icache_range((unsigned long)insn_p,
(unsigned long)insn_p + sizeof(*insn_p));
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