arm/imx21: add kbuild support for the Freescale i.MX21

* adds Kconfig variables
* specifies different physical address for i.MX21 because of the
  different memory layouts
* disables support for UART5/UART6 in the i.MX serial driver
  (the i.MX21 doesn't have those modules)

Based on code from "Martin Fuzzey" <mfuzzey@gmail.com>
Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/arm/mach-mx2/Kconfig

 comment "MX2 family CPU support"
 	depends on ARCH_MX2
 
+choice
+	prompt "MX2 Type"
+	depends on ARCH_MX2
+	default MACH_MX21
+
+config MACH_MX21
+	bool "i.MX21 support"
+	depends on ARCH_MX2
+	help
+	  This enables support for Freescale's MX2 based i.MX21 processor.
+
 config MACH_MX27
 	bool "i.MX27 support"
 	depends on ARCH_MX2
 	help
 	  This enables support for Freescale's MX2 based i.MX27 processor.
 
+endchoice
+
 comment "MX2 Platforms"
 	depends on ARCH_MX2
 

arch/arm/mach-mx2/Makefile.boot

-   zreladdr-y	:= 0xA0008000
-params_phys-y	:= 0xA0000100
-initrd_phys-y	:= 0xA0800000
+zreladdr-$(CONFIG_MACH_MX21)	:= 0xC0008000
+params_phys-$(CONFIG_MACH_MX21)	:= 0xC0000100
+initrd_phys-$(CONFIG_MACH_MX21)	:= 0xC0800000
+
+zreladdr-$(CONFIG_MACH_MX27)	:= 0xA0008000
+params_phys-$(CONFIG_MACH_MX27)	:= 0xA0000100
+initrd_phys-$(CONFIG_MACH_MX27)	:= 0xA0800000

arch/arm/mach-mx2/serial.c

@@ -99,6 +99,7 @@ struct platform_device mxc_uart_device3 = {
 	.num_resources = ARRAY_SIZE(uart3),
 };
 
+#ifdef CONFIG_MACH_MX27
 static struct resource uart4[] = {
 	{
 		.start = UART5_BASE_ADDR,
@@ -136,3 +137,4 @@ struct platform_device mxc_uart_device5 = {
 	.resource = uart5,
 	.num_resources = ARRAY_SIZE(uart5),
 };
+#endif

arch/arm/plat-mxc/include/mach/memory.h

@@ -14,7 +14,12 @@
 #if defined CONFIG_ARCH_MX1
 #define PHYS_OFFSET		UL(0x08000000)
 #elif defined CONFIG_ARCH_MX2
+#ifdef CONFIG_MACH_MX21
+#define PHYS_OFFSET		UL(0xC0000000)
+#endif
+#ifdef CONFIG_MACH_MX27
 #define PHYS_OFFSET		UL(0xA0000000)
+#endif
 #elif defined CONFIG_ARCH_MX3
 #define PHYS_OFFSET		UL(0x80000000)
 #endif

arch/arm/plat-mxc/include/mach/mxc.h

@@ -29,6 +29,10 @@
 # define cpu_is_mx31() (0)
 #endif
 
+#ifndef CONFIG_MACH_MX21
+# define cpu_is_mx21() (0)
+#endif
+
 #ifndef CONFIG_MACH_MX27
 # define cpu_is_mx27() (0)
 #endif