[U-Boot] [Patch v2 2/7] armv8: fsl-layerscape: Increase L2 Data RAM latency and L2 Tag RAM latency

[Gong Qianyu]

From: Mingkai Hu <mingkai.hu at nxp.com>

According to design specification, the L2 cache operates at the same
frequency as the A72 CPUs in the cluster with a 3-cycle latency, so
increase the L2 Data RAM and Tag RAM latency to 3 cycles, or else,
will run into different call trace issues.

Signed-off-by: Mingkai Hu <mingkai.hu at nxp.com>
Signed-off-by: Gong Qianyu <Qianyu.Gong at nxp.com>
---
v2:
 - Revise commit message.

 arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S b/arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S
index 5af6b73..6451a36 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S
+++ b/arch/arm/cpu/armv8/fsl-layerscape/lowlevel.S
@@ -179,6 +179,21 @@ ENTRY(lowlevel_init)
 	isb
 	dsb	sy
 #endif
+
+#ifdef CONFIG_LS1046A
+	/* Initialize the L2 RAM latency */
+	mrs   x1, S3_1_c11_c0_2
+	mov   x0, #0x1C7
+	/* Clear L2 Tag RAM latency and L2 Data RAM latency */
+	bic   x1, x1, x0
+	/* Set L2 data ram latency bits [2:0] */
+	orr   x1, x1, #0x2
+	/* set L2 tag ram latency bits [8:6] */
+	orr   x1,  x1, #0x80
+	msr   S3_1_c11_c0_2, x1
+	isb
+#endif
+
 	mov	lr, x29			/* Restore LR */
 	ret
 ENDPROC(lowlevel_init)
-- 
2.1.0.27.g96db324