[MIPS] vpe: handle halting TCs in an errata safe way.
Adds a JR.HB after halting a TC, to ensure that the TC has really halted.
only modifies the TCSTATUS register when the TC is safely halted.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/vpe.c b/arch/mips/kernel/vpe.c
index 436a64f..38bd33f 100644
--- a/arch/mips/kernel/vpe.c
+++ b/arch/mips/kernel/vpe.c
@@ -1003,6 +1003,7 @@
write_tc_c0_tcstatus(tmp);
write_tc_c0_tchalt(TCHALT_H);
+ mips_ihb();
/* bind it to anything other than VPE1 */
// write_tc_c0_tcbind(read_tc_c0_tcbind() & ~TCBIND_CURVPE); // | TCBIND_CURVPE
@@ -1235,9 +1236,12 @@
settc(t->index);
write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
- /* mark the TC unallocated and halt'ed */
- write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);
+ /* halt the TC */
write_tc_c0_tchalt(TCHALT_H);
+ mips_ihb();
+
+ /* mark the TC unallocated */
+ write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);
v->state = VPE_STATE_UNUSED;
@@ -1533,14 +1537,16 @@
t->pvpe = get_vpe(0); /* set the parent vpe */
}
+ /* halt the TC */
+ write_tc_c0_tchalt(TCHALT_H);
+ mips_ihb();
+
tmp = read_tc_c0_tcstatus();
/* mark not activated and not dynamically allocatable */
tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
tmp |= TCSTATUS_IXMT; /* interrupt exempt */
write_tc_c0_tcstatus(tmp);
-
- write_tc_c0_tchalt(TCHALT_H);
}
}