Options revision 1.2
1Here is a list of hp300 specific kernel compilation options and what they
2mean:
3
4HAVEVAC
5	Compiles in support for virtually addressed cache (VAC) found on
6	hp320 and 350 machines.  Should only be defined when HP320 and/or
7	HP350 is.
8
9HP320
10	Support for old hp320 machines: 16mhz 68020, HP MMU, 16mhz 68881
11	and VAC.  Compiles in support for a VAC, HP MMU, and the 98620A
12	16-bit DMA channel.  Forces the definition of HAVEVAC.
13
14HP350
15	Support for old hp350 machines: 25mhz 68020, HP MMU, 20mhz 68881
16	and VAC.  Compiles in support for a VAC and the HP MMU.  Differs
17	from HP320 in that it has no support for 16-bit DMA controller.
18	Forces the definition of HAVEVAC.
19
20HP330
21	Support for old hp330 (and 318/319) machines: 16mhz 68020, 68551 PMMU
22	and 16mhz 68881.  Compiles in support for PMMU.
23
24HP360
25	Support for old hp360 (and 340) machines: 25mhz 68030+MMU and 25mhz
26	68882.  Compiles in support for PMMU and 68030.  Differs from HP330
27	in support for 68030 on-chip data cache.
28
29HP370
30	Support for old hp370 (and current 345/375/400) machines: 33 (50) mhz
31	68030+MMU and 33 (50) mhz 68882.  Compiles in support for PMMU, 68030
32	and off-chip physically addressed cache.  Differs from 360 in only one
33	place, in dealing with flushing the external cache.
34
35HP380
36	Support for "current" hp380/425 (and 433) machines: 25 (33) mhz 68040
37	with MMU/FPU.  Compiles in support for 68040.
38
39FPSP
40	Compiles in support to link with Motorola's 68040 FP emulation
41	library.  Kernel will build and run without this option, but many
42	binaries will core dump.  Should not be defined unless HP380 is.
43
44
45USELEDS
46	Twinkle the hp4xx front panel (or hp3xx internal) LEDs in the HP
47	designated way.  Somewhat frivolous, but the heartbeat LED is
48	useful to see if your machine is alive.
49
50PANICBUTTON
51	Compiles in code which will enable a "force-crash" HIL keyboard
52	sequence.  When the Reset key is typed twice in succession (within
53	half a second) the kernel will panic.  Note that the HIL Reset key
54	sends a NMI to the processor which will get the CPUs attention no
55	matter what it is doing (i.e. as long as it isn't halted).  Alas,
56	also note that the NMI is only sent when the keyboard is in "cooked"
57	(ITE) mode.  If it is in "raw" mode (i.e. X-server is running) the
58	Reset key is just another keypress event.  A cheezy substitute in
59	this case is holding down the upper right-most unlabeled key and
60	then pressing the unlabeled key to its left.  Note that this only
61	works if HIL (level 1) interrupts are not masked.
62
63DEBUG
64	Compiles in a variety of consistency checks and debug printfs
65	throughout the hp300 MD code and device drivers.
66
67COMPAT_HPUX
68	Enables HP-UX binary compatibility mode.  Allows a variety of
69	"recent" HP-UX binaries to be run unchanged.  Due to the
70	evolutionary and "as-needed" nature of this code, "recent" is
71	anywhere from release 6.2 to 8.0 of HP-UX.  It will run 8.0
72	shared-library binaries (assuming all the necessary shared-libraries
73	are installed in the filesystem).
74
75COMPAT_OHPUX
76	Compile in old 4.2-ish HP-UX (pre-6.0?) compatibility code.
77
78FPCOPROC
79	Compile in code to support the 68881 and above FPU.  Should always
80	be defined, since all supported SPUs have one.  Don't even know if
81	it will compile, much less work,  without this option.  Defined in
82	the prototype makefile (hp300/conf/Makefile.hp300).
83
84DCMSTATS
85	Compile in code to collect a variety of transmit/receive statistics
86	for the 98642 4-port MUX.
87
88WAITHIST
89	Compile in code to collect statistics about the distribution of
90	wait-times for various busy waits in the SCSI host-adaptor driver.
91
92STACKCHECK
93	Enables two types of kernel stack checking in hp300/hp300/locore.s:
94	1. stack "overflow".  On every clock interrupt we ensure that
95	   the current kernel stack has not grown into the user struct
96	   page, i.e. size exceeded UPAGES-1 pages.
97	2. stack "underflow".  Before every rte to user mode we ensure
98	   that we will be exactly at the base of the stack after the
99	   exception frame has been popped.
100	This option can degrade performance considerably, use it only if
101	you suspect a problem with kernel stacks.
102
103SCSI_REVPRI
104	Changes autoconf to start matching logical SCSI devices starting
105	at slave 6 and working backwards instead of starting at slave 0
106	and working up.  Later releases of the HP boot ROM search for
107	boot devices in this manner.  This is apparently the order in
108	which priority is given to slaves on the host adaptor.  Define
109	this if you use wildcarding and want to stay in sync with the
110	boot ROM's strategy.
111
112MAPPEDCOPY
113	Use page remapping to do large copyin/copyouts.  When defined
114	the default is to use mapped copy for operations on one page
115	or more except on machines with virtually-indexed caches.
116	See initcpu() in machdep.c
117
118BUFFERS_UNMANAGED
119	Set up the buffer cache "below" the machine independent VM.
120	Normally, in startup() we use vm_map operations to initially
121	assign physical memory to the buffers.  This creates a map with
122	a huge number of map entries (twice the number of buffers)
123	which serve no purpose since remaining buffer operations
124	(i.e. pagemove) work below the MI layer anyway.  Defining this
125	symbol will cause startup() to use pmap operations to map the
126	initial pages leaving the buffer_map one big entry.
127