MIPS: Netlogic: Handle XLP hardware errata
Core configuration register IFU_BRUB_RESERVE has to be setup to handle
a silicon errata which can result in a CPU hang.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8902/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/netlogic/common/reset.S b/arch/mips/netlogic/common/reset.S
index 701c4bc..e3e5189 100644
--- a/arch/mips/netlogic/common/reset.S
+++ b/arch/mips/netlogic/common/reset.S
@@ -235,6 +235,26 @@
mfc0 v0, CP0_EBASE, 1
andi v0, 0x3ff /* v0 <- node/core */
+ /*
+ * Errata: to avoid potential live lock, setup IFU_BRUB_RESERVE
+ * when running 4 threads per core
+ */
+ andi v1, v0, 0x3 /* v1 <- thread id */
+ bnez v1, 2f
+ nop
+
+ /* thread 0 of each core. */
+ li t0, CKSEG1ADDR(RESET_DATA_PHYS)
+ lw t1, BOOT_THREAD_MODE(t0) /* t1 <- thread mode */
+ subu t1, 0x3 /* 4-thread per core mode? */
+ bnez t1, 2f
+ nop
+
+ li t0, IFU_BRUB_RESERVE
+ li t1, 0x55
+ mtcr t1, t0
+ _ehb
+2:
beqz v0, 4f /* boot cpu (cpuid == 0)? */
nop