MIPS: CPS: Copy EVA configuration when starting secondary VPs.

When starting secondary VPEs which support EVA and the SegCtl registers,
copy the memory segmentation configuration from the running VPE to ensure
that all VPEs in the core have a consistent virtual memory map.

The EVA configuration of secondary cores is dealt with when starting the
core via the CM.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13291/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/cps-vec.S

@@ -441,6 +441,21 @@ LEAF(mips_cps_boot_vpes)
 	mfc0	t0, CP0_CONFIG
 	mttc0	t0, CP0_CONFIG
 
+	/*
+	 * Copy the EVA config from this VPE if the CPU supports it.
+	 * CONFIG3 must exist to be running MT startup - just read it.
+	 */
+	mfc0	t0, CP0_CONFIG, 3
+	and	t0, t0, MIPS_CONF3_SC
+	beqz	t0, 3f
+	 nop
+	mfc0    t0, CP0_SEGCTL0
+	mttc0	t0, CP0_SEGCTL0
+	mfc0    t0, CP0_SEGCTL1
+	mttc0	t0, CP0_SEGCTL1
+	mfc0    t0, CP0_SEGCTL2
+	mttc0	t0, CP0_SEGCTL2
+3:
 	/* Ensure no software interrupts are pending */
 	mttc0	zero, CP0_CAUSE
 	mttc0	zero, CP0_STATUS