+=====================================
+Amiga Buddha and Catweasel IDE Driver
+=====================================
The Amiga Buddha and Catweasel IDE Driver (part of ide.c) was written by
Geert Uytterhoeven based on the following specifications:
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:
+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
+ 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
The local memory-map is even active when mapped to $e8:
+============== ===========================================
$0-$7e Autokonfig-space, see Z-II docs.
$80-$7fd reserved
$b00-$bff IDE-Select 3 (Port 1, Register set 1)
$c00-$cff IDE-Select 4 (Port 2, Register set 0,
- Catweasel only!)
+ Catweasel only!)
$d00-$dff IDE-Select 5 (Port 3, Register set 1,
- Catweasel only!)
+ Catweasel only!)
-$e00-$eff local expansion port, on Catweasel Z-II the
+$e00-$eff local expansion port, on Catweasel Z-II the
Catweasel registers are also mapped here.
Never touch, use multidisk.device!
-
-$f00 read only, Byte-access: Bit 7 shows the
- level of the IRQ-line of IDE port 0.
+
+$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.
+$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.
+$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
+ 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
+ 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. 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
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
+
+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
(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)
+ 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)
+ 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)
+ 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)
+ 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)
+ 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)
+ 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)
+ 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)
+ 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.
+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
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
+Jens Schönfeld february 19th, 1997
+
+updated may 27th, 1997
+eMail: sysop@nostlgic.tng.oche.de
projects / platform / kernel / linux-starfive.git / commitdiff