1 comment "Processor Type"
5 select CPU_HAS_NO_BITFIELDS
7 The Freescale (was Motorola) 68000 CPU is the first generation of
8 the well known M68K family of processors. The CPU core as well as
9 being available as a stand alone CPU was also used in many
10 System-On-Chip devices (eg 68328, 68302, etc). It does not contain
15 select CPU_HAS_NO_BITFIELDS
17 The Freescale (was then Motorola) CPU32 is a CPU core that is
18 based on the 68020 processor. For the most part it is used in
19 System-On-Chip parts, and does not contain a paging MMU.
24 select ARCH_REQUIRE_GPIOLIB
25 select CPU_HAS_NO_BITFIELDS
27 The Freescale ColdFire family of processors is a modern derivitive
28 of the 68000 processor family. They are mainly targeted at embedded
29 applications, and are all System-On-Chip (SOC) devices, as opposed
30 to stand alone CPUs. They implement a subset of the original 68000
31 processor instruction set.
37 If you anticipate running this kernel on a computer with a MC68020
38 processor, say Y. Otherwise, say N. Note that the 68020 requires a
39 68851 MMU (Memory Management Unit) to run Linux/m68k, except on the
40 Sun 3, which provides its own version.
44 depends on MMU && !MMU_SUN3
46 If you anticipate running this kernel on a computer with a MC68030
47 processor, say Y. Otherwise, say N. Note that a MC68EC030 will not
48 work, as it does not include an MMU (Memory Management Unit).
52 depends on MMU && !MMU_SUN3
54 If you anticipate running this kernel on a computer with a MC68LC040
55 or MC68040 processor, say Y. Otherwise, say N. Note that an
56 MC68EC040 will not work, as it does not include an MMU (Memory
61 depends on MMU && !MMU_SUN3
63 If you anticipate running this kernel on a computer with a MC68060
64 processor, say Y. Otherwise, say N.
71 Motorola 68328 processor support.
78 Motorola 68EX328 processor support.
85 Motorola 68VZ328 processor support.
92 Motorola 68360 processor support.
101 Motorola ColdFire 5206 processor support.
107 select COLDFIRE_SW_A7
110 Motorola ColdFire 5206e processor support.
116 select GENERIC_CLOCKEVENTS
117 select HAVE_CACHE_SPLIT
119 Freescale Coldfire 5207/5208 processor support.
125 select GENERIC_CLOCKEVENTS
126 select HAVE_CACHE_SPLIT
129 Freescale Coldfire 5230/1/2/4/5 processor support
135 select COLDFIRE_SW_A7
138 Motorola ColdFire 5249 processor support.
148 select HAVE_CACHE_SPLIT
150 select GENERIC_CLOCKEVENTS
152 Freescale (Motorola) ColdFire 5270/5271 processor support.
158 select COLDFIRE_SW_A7
161 Motorola ColdFire 5272 processor support.
168 select HAVE_CACHE_SPLIT
170 select GENERIC_CLOCKEVENTS
172 Freescale (Motorola) ColdFire 5274/5275 processor support.
178 select GENERIC_CLOCKEVENTS
179 select HAVE_CACHE_SPLIT
182 Motorola ColdFire 5280/5282 processor support.
188 select COLDFIRE_SW_A7
192 Motorola ColdFire 5307 processor support.
200 Freescale (Motorola) ColdFire 532x processor support.
206 select COLDFIRE_SW_A7
210 Motorola ColdFire 5407 processor support.
223 Freescale ColdFire 5470/5471/5472/5473/5474/5475 processor support.
233 Freescale ColdFire 5480/5481/5482/5483/5484/5485 processor support.
236 comment "Processor Specific Options"
239 bool "Math emulation support (EXPERIMENTAL)"
241 depends on EXPERIMENTAL
243 At some point in the future, this will cause floating-point math
244 instructions to be emulated by the kernel on machines that lack a
245 floating-point math coprocessor. Thrill-seekers and chronically
246 sleep-deprived psychotic hacker types can say Y now, everyone else
247 should probably wait a while.
249 config M68KFPU_EMU_EXTRAPREC
250 bool "Math emulation extra precision"
251 depends on M68KFPU_EMU
253 The fpu uses normally a few bit more during calculations for
254 correct rounding, the emulator can (often) do the same but this
255 extra calculation can cost quite some time, so you can disable
256 it here. The emulator will then "only" calculate with a 64 bit
257 mantissa and round slightly incorrect, what is more than enough
260 config M68KFPU_EMU_ONLY
261 bool "Math emulation only kernel"
262 depends on M68KFPU_EMU
264 This option prevents any floating-point instructions from being
265 compiled into the kernel, thereby the kernel doesn't save any
266 floating point context anymore during task switches, so this
267 kernel will only be usable on machines without a floating-point
268 math coprocessor. This makes the kernel a bit faster as no tests
269 needs to be executed whether a floating-point instruction in the
270 kernel should be executed or not.
273 bool "Advanced configuration options"
276 This gives you access to some advanced options for the CPU. The
277 defaults should be fine for most users, but these options may make
278 it possible for you to improve performance somewhat if you know what
281 Note that the answer to this question won't directly affect the
282 kernel: saying N will just cause the configurator to skip all
283 the questions about these options.
285 Most users should say N to this question.
288 bool "Use read-modify-write instructions"
291 This allows to use certain instructions that work with indivisible
292 read-modify-write bus cycles. While this is faster than the
293 workaround of disabling interrupts, it can conflict with DMA
294 ( = direct memory access) on many Amiga systems, and it is also said
295 to destabilize other machines. It is very likely that this will
296 cause serious problems on any Amiga or Atari Medusa if set. The only
297 configuration where it should work are 68030-based Ataris, where it
298 apparently improves performance. But you've been warned! Unless you
299 really know what you are doing, say N. Try Y only if you're quite
302 config SINGLE_MEMORY_CHUNK
303 bool "Use one physical chunk of memory only" if ADVANCED && !SUN3
306 select NEED_MULTIPLE_NODES
308 Ignore all but the first contiguous chunk of physical memory for VM
309 purposes. This will save a few bytes kernel size and may speed up
310 some operations. Say N if not sure.
312 config ARCH_DISCONTIGMEM_ENABLE
313 def_bool MMU && !SINGLE_MEMORY_CHUNK
315 config 060_WRITETHROUGH
316 bool "Use write-through caching for 68060 supervisor accesses"
317 depends on ADVANCED && M68060
319 The 68060 generally uses copyback caching of recently accessed data.
320 Copyback caching means that memory writes will be held in an on-chip
321 cache and only written back to memory some time later. Saying Y
322 here will force supervisor (kernel) accesses to use writethrough
323 caching. Writethrough caching means that data is written to memory
324 straight away, so that cache and memory data always agree.
325 Writethrough caching is less efficient, but is needed for some
326 drivers on 68060 based systems where the 68060 bus snooping signal
327 is hardwired on. The 53c710 SCSI driver is known to suffer from
338 depends on !SINGLE_MEMORY_CHUNK
343 config COLDFIRE_SW_A7
346 config HAVE_CACHE_SPLIT
359 bool "Enable setting the CPU clock frequency"
363 On some CPU's you do not need to know what the core CPU clock
364 frequency is. On these you can disable clock setting. On some
365 traditional 68K parts, and on all ColdFire parts you need to set
366 the appropriate CPU clock frequency. On these devices many of the
367 onboard peripherals derive their timing from the master CPU clock
371 int "Set the core clock frequency"
375 Define the CPU clock frequency in use. This is the core clock
376 frequency, it may or may not be the same as the external clock
377 crystal fitted to your board. Some processors have an internal
378 PLL and can have their frequency programmed at run time, others
379 use internal dividers. In general the kernel won't setup a PLL
380 if it is fitted (there are some exceptions). This value will be
381 specific to the exact CPU that you are using.
384 bool "Old mask 5307 (1H55J) silicon"
387 Build support for the older revision ColdFire 5307 silicon.
388 Specifically this is the 1H55J mask revision.
392 prompt "Split Cache Configuration"
398 Use all of the ColdFire CPU cache memory as an instruction cache.
403 Use all of the ColdFire CPU cache memory as a data cache.
408 Split the ColdFire CPU cache, and use half as an instruction cache
409 and half as a data cache.
415 prompt "Data cache mode"
416 default CACHE_WRITETHRU
418 config CACHE_WRITETHRU
421 The ColdFire CPU cache is set into Write-through mode.
423 config CACHE_COPYBACK
426 The ColdFire CPU cache is set into Copy-back mode.