1 comment "Processor Type"
4 prompt "CPU family support"
5 default M68KCLASSIC if MMU
6 default COLDFIRE if !MMU
8 The Freescale (was Motorola) M68K family of processors implements
9 the full 68000 processor instruction set.
10 The Freescale ColdFire family of processors is a modern derivative
11 of the 68000 processor family. They are mainly targeted at embedded
12 applications, and are all System-On-Chip (SOC) devices, as opposed
13 to stand alone CPUs. They implement a subset of the original 68000
14 processor instruction set.
15 If you anticipate running this kernel on a computer with a classic
16 MC68xxx processor, select M68KCLASSIC.
17 If you anticipate running this kernel on a computer with a ColdFire
18 processor, select COLDFIRE.
21 bool "Classic M68K CPU family support"
24 bool "Coldfire CPU family support"
26 select ARCH_REQUIRE_GPIOLIB
27 select ARCH_HAVE_CUSTOM_GPIO_H
28 select CPU_HAS_NO_BITFIELDS
29 select CPU_HAS_NO_MULDIV64
38 select CPU_HAS_NO_BITFIELDS
39 select CPU_HAS_NO_MULDIV64
42 The Freescale (was Motorola) 68000 CPU is the first generation of
43 the well known M68K family of processors. The CPU core as well as
44 being available as a stand alone CPU was also used in many
45 System-On-Chip devices (eg 68328, 68302, etc). It does not contain
50 select CPU_HAS_NO_BITFIELDS
52 The Freescale (was then Motorola) CPU32 is a CPU core that is
53 based on the 68020 processor. For the most part it is used in
54 System-On-Chip parts, and does not contain a paging MMU.
59 select GENERIC_ATOMIC64
60 select CPU_HAS_ADDRESS_SPACES
62 If you anticipate running this kernel on a computer with a MC68020
63 processor, say Y. Otherwise, say N. Note that the 68020 requires a
64 68851 MMU (Memory Management Unit) to run Linux/m68k, except on the
65 Sun 3, which provides its own version.
69 depends on MMU && !MMU_SUN3
70 select GENERIC_ATOMIC64
71 select CPU_HAS_ADDRESS_SPACES
73 If you anticipate running this kernel on a computer with a MC68030
74 processor, say Y. Otherwise, say N. Note that a MC68EC030 will not
75 work, as it does not include an MMU (Memory Management Unit).
79 depends on MMU && !MMU_SUN3
80 select GENERIC_ATOMIC64
81 select CPU_HAS_ADDRESS_SPACES
83 If you anticipate running this kernel on a computer with a MC68LC040
84 or MC68040 processor, say Y. Otherwise, say N. Note that an
85 MC68EC040 will not work, as it does not include an MMU (Memory
90 depends on MMU && !MMU_SUN3
91 select GENERIC_ATOMIC64
92 select CPU_HAS_ADDRESS_SPACES
94 If you anticipate running this kernel on a computer with a MC68060
95 processor, say Y. Otherwise, say N.
102 Motorola 68328 processor support.
109 Motorola 68EX328 processor support.
116 Motorola 68VZ328 processor support.
123 Motorola 68360 processor support.
132 select COLDFIRE_SW_A7
135 Motorola ColdFire 5206 processor support.
140 select COLDFIRE_SW_A7
143 Motorola ColdFire 5206e processor support.
148 select GENERIC_CLOCKEVENTS
149 select HAVE_CACHE_SPLIT
151 Freescale Coldfire 5207/5208 processor support.
156 select GENERIC_CLOCKEVENTS
157 select HAVE_CACHE_SPLIT
160 Freescale Coldfire 5230/1/2/4/5 processor support
165 select COLDFIRE_SW_A7
168 Motorola ColdFire 5249 processor support.
177 select HAVE_CACHE_SPLIT
179 select GENERIC_CLOCKEVENTS
181 Freescale (Motorola) ColdFire 5270/5271 processor support.
186 select COLDFIRE_SW_A7
189 Motorola ColdFire 5272 processor support.
195 select HAVE_CACHE_SPLIT
197 select GENERIC_CLOCKEVENTS
199 Freescale (Motorola) ColdFire 5274/5275 processor support.
204 select GENERIC_CLOCKEVENTS
205 select HAVE_CACHE_SPLIT
208 Motorola ColdFire 5280/5282 processor support.
213 select COLDFIRE_SW_A7
217 Motorola ColdFire 5307 processor support.
224 Freescale (Motorola) ColdFire 532x processor support.
229 select COLDFIRE_SW_A7
233 Motorola ColdFire 5407 processor support.
241 select MMU_COLDFIRE if MMU
245 Freescale ColdFire 5470/5471/5472/5473/5474/5475 processor support.
249 select MMU_COLDFIRE if MMU
254 Freescale ColdFire 5480/5481/5482/5483/5484/5485 processor support.
259 comment "Processor Specific Options"
262 bool "Math emulation support (EXPERIMENTAL)"
264 depends on EXPERIMENTAL
266 At some point in the future, this will cause floating-point math
267 instructions to be emulated by the kernel on machines that lack a
268 floating-point math coprocessor. Thrill-seekers and chronically
269 sleep-deprived psychotic hacker types can say Y now, everyone else
270 should probably wait a while.
272 config M68KFPU_EMU_EXTRAPREC
273 bool "Math emulation extra precision"
274 depends on M68KFPU_EMU
276 The fpu uses normally a few bit more during calculations for
277 correct rounding, the emulator can (often) do the same but this
278 extra calculation can cost quite some time, so you can disable
279 it here. The emulator will then "only" calculate with a 64 bit
280 mantissa and round slightly incorrect, what is more than enough
283 config M68KFPU_EMU_ONLY
284 bool "Math emulation only kernel"
285 depends on M68KFPU_EMU
287 This option prevents any floating-point instructions from being
288 compiled into the kernel, thereby the kernel doesn't save any
289 floating point context anymore during task switches, so this
290 kernel will only be usable on machines without a floating-point
291 math coprocessor. This makes the kernel a bit faster as no tests
292 needs to be executed whether a floating-point instruction in the
293 kernel should be executed or not.
296 bool "Advanced configuration options"
299 This gives you access to some advanced options for the CPU. The
300 defaults should be fine for most users, but these options may make
301 it possible for you to improve performance somewhat if you know what
304 Note that the answer to this question won't directly affect the
305 kernel: saying N will just cause the configurator to skip all
306 the questions about these options.
308 Most users should say N to this question.
311 bool "Use read-modify-write instructions"
314 This allows to use certain instructions that work with indivisible
315 read-modify-write bus cycles. While this is faster than the
316 workaround of disabling interrupts, it can conflict with DMA
317 ( = direct memory access) on many Amiga systems, and it is also said
318 to destabilize other machines. It is very likely that this will
319 cause serious problems on any Amiga or Atari Medusa if set. The only
320 configuration where it should work are 68030-based Ataris, where it
321 apparently improves performance. But you've been warned! Unless you
322 really know what you are doing, say N. Try Y only if you're quite
325 config SINGLE_MEMORY_CHUNK
326 bool "Use one physical chunk of memory only" if ADVANCED && !SUN3
329 select NEED_MULTIPLE_NODES
331 Ignore all but the first contiguous chunk of physical memory for VM
332 purposes. This will save a few bytes kernel size and may speed up
333 some operations. Say N if not sure.
335 config ARCH_DISCONTIGMEM_ENABLE
336 def_bool MMU && !SINGLE_MEMORY_CHUNK
338 config 060_WRITETHROUGH
339 bool "Use write-through caching for 68060 supervisor accesses"
340 depends on ADVANCED && M68060
342 The 68060 generally uses copyback caching of recently accessed data.
343 Copyback caching means that memory writes will be held in an on-chip
344 cache and only written back to memory some time later. Saying Y
345 here will force supervisor (kernel) accesses to use writethrough
346 caching. Writethrough caching means that data is written to memory
347 straight away, so that cache and memory data always agree.
348 Writethrough caching is less efficient, but is needed for some
349 drivers on 68060 based systems where the 68060 bus snooping signal
350 is hardwired on. The 53c710 SCSI driver is known to suffer from
361 depends on !SINGLE_MEMORY_CHUNK
366 config COLDFIRE_SW_A7
369 config HAVE_CACHE_SPLIT
382 bool "Enable setting the CPU clock frequency"
386 On some CPU's you do not need to know what the core CPU clock
387 frequency is. On these you can disable clock setting. On some
388 traditional 68K parts, and on all ColdFire parts you need to set
389 the appropriate CPU clock frequency. On these devices many of the
390 onboard peripherals derive their timing from the master CPU clock
394 int "Set the core clock frequency"
398 Define the CPU clock frequency in use. This is the core clock
399 frequency, it may or may not be the same as the external clock
400 crystal fitted to your board. Some processors have an internal
401 PLL and can have their frequency programmed at run time, others
402 use internal dividers. In general the kernel won't setup a PLL
403 if it is fitted (there are some exceptions). This value will be
404 specific to the exact CPU that you are using.
407 bool "Old mask 5307 (1H55J) silicon"
410 Build support for the older revision ColdFire 5307 silicon.
411 Specifically this is the 1H55J mask revision.
415 prompt "Split Cache Configuration"
421 Use all of the ColdFire CPU cache memory as an instruction cache.
426 Use all of the ColdFire CPU cache memory as a data cache.
431 Split the ColdFire CPU cache, and use half as an instruction cache
432 and half as a data cache.
438 prompt "Data cache mode"
439 default CACHE_WRITETHRU
441 config CACHE_WRITETHRU
444 The ColdFire CPU cache is set into Write-through mode.
446 config CACHE_COPYBACK
449 The ColdFire CPU cache is set into Copy-back mode.