1 S3C24XX ARM Linux Overview
2 ==========================
9 The Samsung S3C24XX range of ARM9 System-on-Chip CPUs are supported
10 by the 's3c2410' architecture of ARM Linux. Currently the S3C2410,
11 S3C2412, S3C2413, S3C2440, S3C2442 and S3C2443 devices are supported.
13 Support for the S3C2400 and S3C24A0 series are in progress.
19 A generic S3C2410 configuration is provided, and can be used as the
20 default by `make s3c2410_defconfig`. This configuration has support
21 for all the machines, and the commonly used features on them.
23 Certain machines may have their own default configurations as well,
24 please check the machine specific documentation.
30 The core support files are located in the platform code contained in
31 arch/arm/plat-s3c24xx with headers in include/asm-arm/plat-s3c24xx.
32 This directory should be kept to items shared between the platform
33 code (arch/arm/plat-s3c24xx) and the arch/arm/mach-s3c24* code.
35 Each cpu has a directory with the support files for it, and the
36 machines that carry the device. For example S3C2410 is contained
37 in arch/arm/mach-s3c2410 and S3C2440 in arch/arm/mach-s3c2440
39 Register, kernel and platform data definitions are held in the
40 arch/arm/mach-s3c2410 directory./include/mach
42 arch/arm/plat-s3c24xx:
44 Files in here are either common to all the s3c24xx family,
45 or are common to only some of them with names to indicate this
46 status. The files that are not common to all are generally named
47 with the initial cpu they support in the series to ensure a short
48 name without any possibility of confusion with newer devices.
50 As an example, initially s3c244x would cover s3c2440 and s3c2442, but
51 with the s3c2443 which does not share many of the same drivers in
52 this directory, the name becomes invalid. We stick to s3c2440-<x>
53 to indicate a driver that is s3c2440 and s3c2442 compatible.
55 This does mean that to find the status of any given SoC, a number
56 of directories may need to be searched.
62 The currently supported machines are as follows:
64 Simtec Electronics EB2410ITX (BAST)
66 A general purpose development board, see EB2410ITX.txt for further
69 Simtec Electronics IM2440D20 (Osiris)
71 CPU Module from Simtec Electronics, with a S3C2440A CPU, nand flash
72 and a PCMCIA controller.
76 Samsung's own development board, geared for PDA work.
80 The S3C2412 version of the SMDK2440.
84 The S3C2412 version of the SMDK2440.
86 Samsung/Meritech SMDK2440
88 The S3C2440 compatible version of the SMDK2440, which has the
89 option of an S3C2440 or S3C2442 CPU module.
97 Handheld (IPAQ), available in several varieties
101 S3C2440 based IPAQ, with a number of variations depending on
106 A S3C2410 based PDA from Acer. There is a Wiki page at
107 http://handhelds.org/moin/moin.cgi/AcerN30Documentation .
111 American Microsystems' M5900
116 Two machines by Nex Vision
122 The architecture has been designed to support as many machines as can
123 be configured for it in one kernel build, and any future additions
124 should keep this in mind before altering items outside of their own
127 Machine definitions should be kept in linux/arch/arm/mach-s3c2410,
128 and there are a number of examples that can be looked at.
130 Read the kernel patch submission policies as well as the
131 Documentation/arm directory before submitting patches. The
132 ARM kernel series is managed by Russell King, and has a patch system
133 located at http://www.arm.linux.org.uk/developer/patches/
134 as well as mailing lists that can be found from the same site.
136 As a courtesy, please notify <ben-linux@fluff.org> of any new
137 machines or other modifications.
139 Any large scale modifications, or new drivers should be discussed
140 on the ARM kernel mailing list (linux-arm-kernel) before being
141 attempted. See http://www.arm.linux.org.uk/mailinglists/ for the
142 mailing list information.
148 The hardware I2C core in the CPU is supported in single master
149 mode, and can be configured via platform data.
155 Support for the onboard RTC unit, including alarm function.
157 This has recently been upgraded to use the new RTC core,
158 and the module has been renamed to rtc-s3c to fit in with
159 the new rtc naming scheme.
165 The onchip watchdog is available via the standard watchdog
172 The current kernels now have support for the s3c2410 NAND
173 controller. If there are any problems the latest linux-mtd
174 code can be found from http://www.linux-mtd.infradead.org/
176 For more information see Documentation/arm/Samsung-S3C24XX/NAND.txt
182 The s3c2410 serial driver provides support for the internal
183 serial ports. These devices appear as /dev/ttySAC0 through 3.
185 To create device nodes for these, use the following commands
187 mknod ttySAC0 c 204 64
188 mknod ttySAC1 c 204 65
189 mknod ttySAC2 c 204 66
195 The core contains support for manipulating the GPIO, see the
196 documentation in GPIO.txt in the same directory as this file.
202 The core provides the interface defined in the header file
203 include/asm-arm/hardware/clock.h, to allow control over the
210 For boards that provide support for suspend to RAM, the
211 system can be placed into low power suspend.
213 See Suspend.txt for more information.
219 SPI drivers are available for both the in-built hardware
220 (although there is no DMA support yet) and a generic
227 There is support for GPIO based LEDs via a platform driver
228 in the LED subsystem.
234 Whenever a device has platform specific data that is specified
235 on a per-machine basis, care should be taken to ensure the
238 1) that default data is not left in the device to confuse the
239 driver if a machine does not set it at startup
241 2) the data should (if possible) be marked as __initdata,
242 to ensure that the data is thrown away if the machine is
243 not the one currently in use.
245 The best way of doing this is to make a function that
246 kmalloc()s an area of memory, and copies the __initdata
247 and then sets the relevant device's platform data. Making
248 the function `__init` takes care of ensuring it is discarded
249 with the rest of the initialisation code
251 static __init void s3c24xx_xxx_set_platdata(struct xxx_data *pd)
253 struct s3c2410_xxx_mach_info *npd;
255 npd = kmalloc(sizeof(struct s3c2410_xxx_mach_info), GFP_KERNEL);
257 memcpy(npd, pd, sizeof(struct s3c2410_xxx_mach_info));
258 s3c_device_xxx.dev.platform_data = npd;
260 printk(KERN_ERR "no memory for xxx platform data\n");
264 Note, since the code is marked as __init, it should not be
265 exported outside arch/arm/mach-s3c2410/, or exported to
266 modules via EXPORT_SYMBOL() and related functions.
280 Guillaume Gourat (NexVision)
281 Christer Weinigel (wingel) (Acer N30)
282 Lucas Correia Villa Real (S3C2400 port)
288 Ben Dooks, (c) 2004-2005,2006 Simtec Electronics