[PATCH v2 2/2] MIPS: CPS: Copy EVA configuration when starting secondary VPs.

From: Matt Redfearn
Date: Wed May 18 2016 - 12:12:59 EST


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@xxxxxxxxxx>
---

Changes in v2:
- Skip check for config3 existing - we know it must to be doing
multithreading
- Use a unique lable name in the function

arch/mips/kernel/cps-vec.S | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/arch/mips/kernel/cps-vec.S b/arch/mips/kernel/cps-vec.S
index ac81edd44563..f8eae9189e38 100644
--- a/arch/mips/kernel/cps-vec.S
+++ b/arch/mips/kernel/cps-vec.S
@@ -431,6 +431,21 @@ 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
--
2.5.0