arm: mach-k3: Move disable_linefill_optimization() into R5 directory

The disable_linefill_optimization() function is only ever loaded by the
R5 core, move the code into the R5 directory.

Signed-off-by: Andrew Davis <afd@ti.com>
Reviewed-by: Igor Opaniuk <igor.opaniuk@foundries.io>
diff --git a/arch/arm/mach-k3/r5/common.c b/arch/arm/mach-k3/r5/common.c
new file mode 100644
index 0000000..ef81f50
--- /dev/null
+++ b/arch/arm/mach-k3/r5/common.c
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * K3: R5 Common Architecture initialization
+ *
+ * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+#include <linux/types.h>
+#include <asm/hardware.h>
+#include <asm/io.h>
+
+#include "../common.h"
+
+void disable_linefill_optimization(void)
+{
+	u32 actlr;
+
+	/*
+	 * On K3 devices there are 2 conditions where R5F can deadlock:
+	 * 1.When software is performing series of store operations to
+	 *   cacheable write back/write allocate memory region and later
+	 *   on software execute barrier operation (DSB or DMB). R5F may
+	 *   hang at the barrier instruction.
+	 * 2.When software is performing a mix of load and store operations
+	 *   within a tight loop and store operations are all writing to
+	 *   cacheable write back/write allocates memory regions, R5F may
+	 *   hang at one of the load instruction.
+	 *
+	 * To avoid the above two conditions disable linefill optimization
+	 * inside Cortex R5F.
+	 */
+	asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (actlr));
+	actlr |= (1 << 13); /* Set DLFO bit  */
+	asm("mcr p15, 0, %0, c1, c0, 1" : : "r" (actlr));
+}