patch-2.3.48 linux/drivers/block/README.buddha

• Lines: 211
• Date: Wed Dec 31 16:00:00 1969
• Orig file: v2.3.47/linux/drivers/block/README.buddha
• Orig date: Mon Aug 9 12:32:28 1999

diff -u --recursive --new-file v2.3.47/linux/drivers/block/README.buddha linux/drivers/block/README.buddha
@@ -1,210 +0,0 @@
-
-The Amiga Buddha and Catweasel IDE Driver (part of ide.c) was written by
-Geert Uytterhoeven based on the following specifications:
-
-------------------------------------------------------------------------
-
-Register map of the Buddha IDE controller and the
-Buddha-part of the Catweasel Zorro-II version
-
-The Autoconfiguration has been implemented just as Commodore
-described  in  their  manuals, no tricks have been used (for
-example leaving some address lines out of the equations...).
-If you want to configure the board yourself (for example let
-a  Linux  kernel  configure the card), look at the Commodore
-Docs.  Reading the nibbles should give this information:
-
-Vendor number: 4626 ($1212)
-product number: 0 (42 for Catweasel Z-II)
-Serial number: 0
-Rom-vector: $1000
-
-The  card  should be a Z-II board, size 64K, not for freemem
-list, Rom-Vektor is valid, no second Autoconfig-board on the
-same card, no space preferrence, supports "Shutup_forever".
-
-Setting  the  base address should be done in two steps, just
-as  the Amiga Kickstart does:  The lower nibble of the 8-Bit
-address is written to $4a, then the whole Byte is written to
-$48, while it doesn't matter how often you're writing to $4a
-as  long as $48 is not touched.  After $48 has been written,
-the  whole card disappears from $e8 and is mapped to the new
-addrress just written.  Make shure $4a is written befor $48,
-otherwise your chance is only 1:16 to find the board :-).
-
-The local memory-map is even active when mapped to $e8:
-
-$0-$7e		Autokonfig-space, see Z-II docs.
-
-$80-$7fd	reserved
-
-$7fe		Speed-select Register: Read & Write
-		(description see further down)
-
-$800-$8ff	IDE-Select 0 (Port 0, Register set 0)
-
-$900-$9ff	IDE-Select 1 (Port 0, Register set 1)
-
-$a00-$aff	IDE-Select 2 (Port 1, Register set 0)
-
-$b00-$bff	IDE-Select 3 (Port 1, Register set 1)
-
-$c00-$cff	IDE-Select 4 (Port 2, Register set 0,
-                          Catweasel only!)
-
-$d00-$dff	IDE-Select 5 (Port 3, Register set 1,
-			      Catweasel only!)
-
-$e00-$eff	local expansion port, on Catweasel Z-II the 
-		Catweasel registers are also mapped here.
-		Never touch, use multidisk.device!
-		
-$f00		read only, Byte-access: Bit 7 shows the 
-		level of the IRQ-line of IDE port 0. 
-
-$f01-$f3f	mirror of $f00
-
-$f40		read only, Byte-access: Bit 7 shows the 
-		level of the IRQ-line of IDE port 1. 
-
-$f41-$f7f	mirror of $f40
-
-$f80		read only, Byte-access: Bit 7 shows the 
-		level of the IRQ-line of IDE port 2. 
-		(Catweasel only!)
-
-$f81-$fbf	mirror of $f80
-
-$fc0		write-only: Writing any value to this
-		register enables IRQs to be passed from the 
-		IDE ports to the Zorro bus. This mechanism 
-		has been implemented to be compatible with 
-		harddisks that are either defective or have
-		a buggy firmware and pull the IRQ line up 
-		while starting up. If interrupts would 
-		always be passed to the bus, the computer 
-		might not start up. Once enabled, this flag 
-		can not be disabled again. The level of the 
-		flag can not be determined by software 
-		(what for? Write to me if it's necessary!).
-
-$fc1-$fff	mirror of $fc0
-
-$1000-$ffff	Buddha-Rom with offset $1000 in the rom
-		chip. The addresses $0 to $fff of the rom 
-		chip cannot be read. Rom is Byte-wide and
-		mapped to even addresses.
-
-The  IDE ports issue an INT2.  You can read the level of the
-IRQ-lines  of  the  IDE-ports by reading from the three (two
-for  Buddha-only)  registers  $f00, $f40 and $f80.  This way
-more  than one I/O request can be handled and you can easily
-determine  what  driver  has  to serve the INT2.  Buddha and
-Catweasel  expansion  boards  can issue an INT6.  A seperate
-memory  map  is available for the I/O module and the sysop's
-I/O module.
-
-The IDE ports are fed by the address lines A2 to A4, just as
-the  Amiga  1200  and  Amiga  4000  IDE ports are.  This way
-existing  drivers  can be easily ported to Buddha.  A move.l
-polls  two  words  out of the same address of IDE port since
-every  word  is  mirrored  once.  movem is not possible, but
-it's  not  necessary  either,  because  you can only speedup
-68000  systems  with  this  technique.   A 68020 system with
-fastmem is faster with move.l.
-
-If you're using the mirrored registers of the IDE-ports with
-A6=1,  the Buddha doesn't care about the speed that you have
-selected  in  the  speed  register (see further down).  With
-A6=1  (for example $840 for port 0, register set 0), a 780ns
-access  is being made.  These registers should be used for a
-command   access   to  the  harddisk/CD-Rom,  since  command
-accesses  are Byte-wide and have to be made slower according
-to the ATA-X3T9 manual.
-
-Now  for the speed-register:  The register is byte-wide, and
-only  the  upper  three  bits are used (Bits 7 to 5).  Bit 4
-must  always  be set to 1 to be compatible with later Buddha
-versions  (if  I'll  ever  update this one).  I presume that
-I'll  never use the lower four bits, but they have to be set
-to 1 by definition.
-  The  values in this table have to be shifted 5 bits to the
-left and or'd with $1f (this sets the lower 5 bits).
-
-All  the timings have in common:  Select and IOR/IOW rise at
-the  same  time.   IOR  and  IOW have a propagation delay of
-about  30ns  to  the clocks on the Zorro bus, that's why the
-values  are no multiple of 71.  One clock-cycle is 71ns long
-(exactly 70,5 at 14,18 Mhz on PAL systems).
-
-value 0 (Default after reset)
-
-497ns Select (7 clock cycles) , IOR/IOW after 172ns (2 clock cycles)
-(same timing as the Amiga 1200 does on it's IDE port without
-accelerator card)
-
-value 1
-
-639ns Select (9 clock cycles), IOR/IOW after 243ns (3 clock cycles)
-
-value 2
-
-781ns Select (11 clock cycles), IOR/IOW after 314ns (4 clock cycles)
-
-value 3
-
-355ns Select (5 clock cycles), IOR/IOW after 101ns (1 clock cycle)
-
-value 4
-
-355ns Select (5 clock cycles), IOR/IOW after 172ns (2 clock cycles)
-
-value 5
-
-355ns Select (5 clock cycles), IOR/IOW after 243ns (3 clock cycles)
-
-value 6
-
-1065ns Select (15 clock cycles), IOR/IOW after 314ns (4 clock cycles)
-
-value 7
-
-355ns Select, (5 clock cycles), IOR/IOW after 101ns (1 clock cycle)
-
-When accessing IDE registers with A6=1 (for example $84x),
-the timing will always be mode 0 8-bit compatible, no matter
-what you have selected in the speed register:
-
-781ns select, IOR/IOW after 4 clock cycles (=314ns) aktive. 
-
-All  the  timings with a very short select-signal (the 355ns
-fast  accesses)  depend  on the accelerator card used in the
-system:  Sometimes two more clock cycles are inserted by the
-bus  interface,  making  the  whole access 497ns long.  This
-doesn't  affect  the  reliability  of the controller nor the
-performance  of  the  card,  since  this doesn't happen very
-often.
-
-All  the  timings  are  calculated  and  only  confirmed  by
-measurements  that allowed me to count the clock cycles.  If
-the  system  is clocked by an oscillator other than 28,37516
-Mhz  (for  example  the  NTSC-frequency  28,63636 Mhz), each
-clock  cycle is shortened to a bit less than 70ns (not worth
-mentioning).   You  could think of a small performance boost
-by  overclocking  the  system,  but  you would either need a
-multisync  monitor,  or  a  graphics card, and your internal
-diskdrive would go crazy, that's why you shouldn't tune your
-Amiga this way.
-
-Giving  you  the  possibility  to  write  software  that  is
-compatible  with both the Buddha and the Catweasel Z-II, The
-Buddha  acts  just  like  a  Catweasel  Z-II  with no device
-connected  to  the  third  IDE-port.   The IRQ-register $f80
-always  shows a "no IRQ here" on the Buddha, and accesses to
-the  third  IDE  port  are  going into data's Nirwana on the
-Buddha.
-
-			    Jens Schönfeld february 19th, 1997
-					updated may 27th, 1997
-			     eMail: sysop@nostlgic.tng.oche.de
-