ARM: vexpress: Move vexpress_flags_set() into arch code

vexpress_flags_set() is only used by the platform SMP related code and
has nothing to do with the vexpress-sysreg MFD driver other than both
access the same h/w block. It's also only needed for 32-bit systems and
must be built-in for them. Let's move vexpress_flags_set() closer to
where it is being used. This will allow for vexpress-sysreg to be built
as a module.

Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>

arch/arm/mach-vexpress/Kconfig

@@ -22,7 +22,6 @@ menuconfig ARCH_VEXPRESS
 	select REGULATOR_FIXED_VOLTAGE if REGULATOR
 	select VEXPRESS_CONFIG
 	select VEXPRESS_SYSCFG
-	select MFD_VEXPRESS_SYSREG
 	help
 	  This option enables support for systems using Cortex processor based
 	  ARM core and logic (FPGA) tiles on the Versatile Express motherboard,

arch/arm/mach-vexpress/core.h

@@ -1,3 +1,4 @@
 bool vexpress_smp_init_ops(void);
+void vexpress_flags_set(u32 data);
 
 extern const struct smp_operations vexpress_smp_dt_ops;

arch/arm/mach-vexpress/dcscb.c

@@ -20,6 +20,7 @@
 #include <asm/cputype.h>
 #include <asm/cp15.h>
 
+#include "core.h"
 
 #define RST_HOLD0	0x0
 #define RST_HOLD1	0x4

arch/arm/mach-vexpress/v2m.c

@@ -1,8 +1,31 @@
 // SPDX-License-Identifier: GPL-2.0
+#include <linux/of.h>
+#include <linux/of_address.h>
 #include <asm/mach/arch.h>
 
 #include "core.h"
 
+#define SYS_FLAGSSET		0x030
+#define SYS_FLAGSCLR		0x034
+
+void vexpress_flags_set(u32 data)
+{
+	static void __iomem *base;
+
+	if (!base) {
+		struct device_node *node = of_find_compatible_node(NULL, NULL,
+				"arm,vexpress-sysreg");
+
+		base = of_iomap(node, 0);
+	}
+
+	if (WARN_ON(!base))
+		return;
+
+	writel(~0, base + SYS_FLAGSCLR);
+	writel(data, base + SYS_FLAGSSET);
+}
+
 static const char * const v2m_dt_match[] __initconst = {
 	"arm,vexpress",
 	NULL,

drivers/mfd/vexpress-sysreg.c

@@ -8,7 +8,6 @@
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/mfd/core.h>
-#include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/platform_data/syscon.h>
 #include <linux/platform_device.h>
@@ -42,24 +41,6 @@
 
 #define SYS_MISC_MASTERSITE	(1 << 14)
 
-void vexpress_flags_set(u32 data)
-{
-	static void __iomem *base;
-
-	if (!base) {
-		struct device_node *node = of_find_compatible_node(NULL, NULL,
-				"arm,vexpress-sysreg");
-
-		base = of_iomap(node, 0);
-	}
-
-	if (WARN_ON(!base))
-		return;
-
-	writel(~0, base + SYS_FLAGSCLR);
-	writel(data, base + SYS_FLAGSSET);
-}
-
 /* The sysreg block is just a random collection of various functions... */
 
 static struct syscon_platform_data vexpress_sysreg_sys_id_pdata = {

include/linux/vexpress.h

@@ -40,8 +40,4 @@ struct device *vexpress_config_bridge_register(struct device *parent,
 
 struct regmap *devm_regmap_init_vexpress_config(struct device *dev);
 
-/* Platform control */
-
-void vexpress_flags_set(u32 data);
-
 #endif