TODO:	specify IDE i/f
	specify ASMI i/f
	specify OCI


===============================================================================
	C P U ,	  M E M O R Y ,	  I N / O U T	C O M P O N E N T S
===============================================================================
see also [1]-[6]

CPU:	"standard_32"
	32 bit NIOS for 50 MHz
	256 Byte for register file (15 levels)
	4 KByte instruction cache (2 bytes in each cache line)
	4 KByte data cache (4 bytes in each cache line)
	2 KByte On Chip ROM with GERMS boot monitor
	no On Chip RAM
	MSTEP multiplier
	no Debug Core
	On Chip Instrumentation (OCI) enabled

	U-Boot CFG:	CONFIG_SYS_NIOS_CPU_CLK	     = 50000000
			CONFIG_SYS_NIOS_CPU_ICACHE	     = 4096
			CONFIG_SYS_NIOS_CPU_DCACHE	     = 4096
			CONFIG_SYS_NIOS_CPU_REG_NUMS	     = 256
			CONFIG_SYS_NIOS_CPU_MUL	     = 0
			CONFIG_SYS_NIOS_CPU_MSTEP	     = 1
			CONFIG_SYS_NIOS_CPU_DBG_CORE	     = 0

OCI:	(TODO)

IRQ:	 Nr.  | used by
	------+--------------------------------------------------------
	 16   | TIMER0	  |  CONFIG_SYS_NIOS_CPU_TIMER0_IRQ = 16
	 25   | UART0	  |  CONFIG_SYS_NIOS_CPU_UART0_IRQ  = 25
	 30   | LAN91C111 |  CONFIG_SYS_NIOS_CPU_LAN0_IRQ   = 30
	 35   | PIO5	  |  CONFIG_SYS_NIOS_CPU_PIO5_IRQ   = 35
	 40   | PIO0	  |  CONFIG_SYS_NIOS_CPU_PIO0_IRQ   = 40
	 45   | ASMI	  |  CONFIG_SYS_NIOS_CPU_ASMI0_IRQ  = 45
	 50   | TIMER1	  |  CONFIG_SYS_NIOS_CPU_TIMER1_IRQ = 50

MEMORY:	 8 MByte Flash
	 1 MByte SRAM
	16 MByte SDRAM

ASMI:	(TODO) <-- ASMI part is 4M bits

Timer:	TIMER0: high priority programmable timer (IRQ16)
	TIMER1: low priority fixed timer for 10 ms @ 50 MHz (IRQ50)

	U-Boot CFG:	CONFIG_SYS_NIOS_CPU_TICK_TIMER	     = 1
			CONFIG_SYS_NIOS_CPU_USER_TIMER	     = 0

PIO:	 Nr.  | description
	------+--------------------------------------------------------
	 PIO0 | BUTTON:	    4 inputs for user push buttons (IRQ40)
	 PIO1 | LCD:	   11 in/outputs for ASCII LCD
	 PIO2 | LED:	    8 outputs for user LEDs
	 PIO3 | SEVENSEG:  16 outputs for user seven segment display
	 PIO4 | RECONF:	    1 in/output for . . . . . . . . . . . .
	 PIO5 | CFPRESENT:  1 input for CF present event (IRQ35)
	 PIO6 | CFPOWER:    1 output to controll CF power supply
	 PIO7 | CFATASEL:   1 output to controll CF ATA card select

	U-Boot CFG:	CONFIG_SYS_NIOS_CPU_BUTTON_PIO	     = 0
			CONFIG_SYS_NIOS_CPU_LCD_PIO	     = 1
			CONFIG_SYS_NIOS_CPU_LED_PIO	     = 2
			CONFIG_SYS_NIOS_CPU_SEVENSEG_PIO    = 3
			CONFIG_SYS_NIOS_CPU_RECONF_PIO	     = 4
			CONFIG_SYS_NIOS_CPU_CFPRESENT_PIO   = 5
			CONFIG_SYS_NIOS_CPU_CFPOWER_PIO     = 6
			CONFIG_SYS_NIOS_CPU_CFATASEL_PIO    = 7

UART:	UART0: fixed baudrate of 115200, fixed protocol 8N1,
	       without handshake RTS/CTS (IRQ25)

LAN:	SMsC LAN91C111 with:
	  - offset 0x300 (LAN91C111_REGISTERS_OFFSET)
	  - data bus width 32 bit (LAN91C111_DATA_BUS_WIDTH)

IDE:	(TODO)


===============================================================================
	M E M O R Y   M A P
===============================================================================

- - - - - - - - - - -  external memory 2  - - - - - - - - - - - - - - - - - - -

  0x02000000 ---32-----------16|15------------0-
	       |	       :	       | \
	       |	       :	       | |
  SDRAM	       |	       :	       |  > CONFIG_SYS_NIOS_CPU_SDRAM_SIZE
	       |	       :	       | |   = 0x01000000
	       |	       :	       | /
  0x01000000 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_SDRAM_BASE
	       |			       |
	       :	      gap	       :
	       :			       :

- - - - - - - - - - -	  on chip i/o	  - - - - - - - - - - - - - - - - - - -

	       :			       :
	       :	      gap	       :
	       |			       |
  0x________ ---32-----------16|15------------0-
	       |	       |	       | \
	       :  (real size   :	       : |
  ASMI i/f     :   and content :	       :  > 0x________
  [5]	       :   unknown)    :	       : |
	       |	       |	       | /
  0x00920b00 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_ASMI0
	       |			       |
	       :	      gap	       :
	       |			       |
  0x00920a80 ---32-----------16|15------------0-
	       |	       |	       | \
	       :  (real size   :	       : |
  IDE i/f      :   and content :	       :  > 0x00000080
  [6]	       :   unknown)    :	       : |
	       |	       |	       | /
  0x00920a00 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_IDE0
	       |		     (unused)  | \
	+ 0x1c |- - - - - - - - - - - - - - - -| |
	       |		     (unused)  | |
	+ 0x18 |- - - - - - - - - - - - - - - -| |
	       |		     (unused)  | |
	+ 0x14 |- - - - - - - - - - - - - - - -| |
  TIMER1       |		     (unused)  | |
  [3]	+ 0x10 |- - - - - - - - - - - - - - - -|  > 0x00000020
	       |		     (unused)  | |
	+ 0x0c |- - - - - - - - - - - - - - - -| |
	       |		     (unused)  | |
	+ 0x08 |- - - - - - - - - - - - - - - -| |
	       |  control (1 bit)	 (rw)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  status (2 bit)	 (rw)  | /
  0x009209e0 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_TIMER1
	       |		     (unused)  | \
	+ 0x0c |- - - - - - - - - - - - - - - -| |
  PIO7	       |		     (unused)  | |
  [4]	+ 0x08 |- - - - - - - - - - - - - - - -|  > 0x00000010
	       |		     (unused)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  data (1 bit)		 (wo)  | /
  0x009209d0 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_PIO7
	       |		     (unused)  | \
	+ 0x0c |- - - - - - - - - - - - - - - -| |
  PIO6	       |		     (unused)  | |
  [4]	+ 0x08 |- - - - - - - - - - - - - - - -|  > 0x00000010
	       |		     (unused)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  data (1 bit)		 (wo)  | /
  0x009209c0 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_PIO6
	       |  edgecapture (1 bit)	 (rw)  | \
	+ 0x0c |- - - - - - - - - - - - - - - -| |
  PIO5	       |  interruptmask (1 bit)	 (rw)  | |
  [4]	+ 0x08 |- - - - - - - - - - - - - - - -|  > 0x00000010
	       |		     (unused)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  data (1 bit)		 (ro)  | /
  0x009209b0 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_PIO5
	       |		     (unused)  | \
	+ 0x0c |- - - - - - - - - - - - - - - -| |
  PIO4	       |		     (unused)  | |
  [4]	+ 0x08 |- - - - - - - - - - - - - - - -|  > 0x00000010
	       |  direction (1 bit)	 (rw)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  data (1 bit)		 (rw)  | /
  0x009209a0 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_PIO4
	       |		     (unused)  | \
	+ 0x0c |- - - - - - - - - - - - - - - -| |
  PIO3	       |		     (unused)  | |
  [4]	+ 0x08 |- - - - - - - - - - - - - - - -|  > 0x00000010
	       |		     (unused)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  data (16 bit)		 (wo)  | /
  0x00920990 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_PIO3
	       |		     (unused)  | \
	+ 0x0c |- - - - - - - - - - - - - - - -| |
  PIO2	       |		     (unused)  | |
  [4]	+ 0x08 |- - - - - - - - - - - - - - - -|  > 0x00000010
	       |		     (unused)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  data (8 bit)		 (wo)  | /
  0x00920980 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_PIO2
	       |		     (unused)  | \
	+ 0x0c |- - - - - - - - - - - - - - - -| |
  PIO1	       |		     (unused)  | |
  [4]	+ 0x08 |- - - - - - - - - - - - - - - -|  > 0x00000010
	       |  direction (11 bit)	 (rw)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  data (11 bit)		 (rw)  | /
  0x00920970 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_PIO1
	       |  edgecapture (4 bit)	 (rw)  | \
	+ 0x0c |- - - - - - - - - - - - - - - -| |
  PIO0	       |  interruptmask (4 bit)	 (rw)  | |
  [4]	+ 0x08 |- - - - - - - - - - - - - - - -|  > 0x00000010
	       |		     (unused)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  data (4 bit)		 (ro)  | /
  0x00920960 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_PIO0
	       |		     (unused)  | \
	+ 0x1c |- - - - - - - - - - - - - - - -| |
	       |		     (unused)  | |
	+ 0x18 |- - - - - - - - - - - - - - - -| |
	       |  snaph (16 bit)	 (rw)  | |
	+ 0x14 |- - - - - - - - - - - - - - - -| |
  TIMER0       |  snapl (16 bit)	 (rw)  | |
  [3]	+ 0x10 |- - - - - - - - - - - - - - - -|  > 0x00000020
	       |  periodh (16 bit)	 (rw)  | |
	+ 0x0c |- - - - - - - - - - - - - - - -| |
	       |  periodl (16 bit)	 (rw)  | |
	+ 0x08 |- - - - - - - - - - - - - - - -| |
	       |  control (4 bit)	 (rw)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  status (2 bit)	 (rw)  | /
  0x00920940 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_TIMER0
	       |			       | \
	       :	      gap	       :  > (space for UART1)
	       |			       | /
  0x00920920 ---32-----------16|15------------0-
	       |		     (unused)  | \
	+ 0x1c |- - - - - - - - - - - - - - - -| |
	       |		     (unused)  | |
	+ 0x18 |- - - - - - - - - - - - - - - -| |
	       |		     (unused)  | |
	+ 0x14 |- - - - - - - - - - - - - - - -| |
  UART0	       |		     (unused)  |  > 0x00000020
  [2]	+ 0x10 |- - - - - - - - - - - - - - - -| |
	       |  control (10 bit)	 (rw)  | |
	+ 0x0c |- - - - - - - - - - - - - - - -| |
	       |  status (10 bit)	 (rw)  | |
	+ 0x08 |- - - - - - - - - - - - - - - -| |
	       |  txdata (8 bit)	 (wo)  | |
	+ 0x04 |- - - - - - - - - - - - - - - -| |
	       |  rxdata (8 bit)	 (ro)  | /
  0x00920900 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_UART0

- - - - - - - - - - -  on chip debugging  - - - - - - - - - - - - - - - - - - -

  0x00920900 -----------------------------------
	       |			       | \
	       :  (real size		       : |
  OCI Debug    :   and content		       :  > CONFIG_SYS_NIOS_CPU_OCI_SIZE
	       :   unknown)		       : |   = 0x00000100
	       |			       | /
  0x00920800 -----------------------------------    CONFIG_SYS_NIOS_CPU_OCI_BASE

- - - - - - - - - - -	on chip memory	  - - - - - - - - - - -

  0x00920800 ---32-----------16|15------------0-
	       |	       :	       | \
	       |	       :	       | |
  GERMS	       |	       :	       |  > CONFIG_SYS_NIOS_CPU_ROM_SIZE
	       |	       :	       | |   = 0x00000800
	       |	       :	       | /
  0x00920000   |- - - - - - - - - - - - - - - -+- - CONFIG_SYS_NIOS_CPU_RST_VECT
  0x00920000 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_ROM_BASE

- - - - - - - - - - -	 external i/o	  - - - - - - - - - - - - - - - - - - -

  0x00920000 ---32-----------16|15------------0-
	       |	      gap	       | \
  0x00910310 --+-------------------------------| |
	       |			       | |
	       |  register bank (size = 0x10)  | |
	       | +--------.---.---.---	       | |
	       | | bank 0 \ 1 \ 2 \ 3 \	       | |
	       | |---------------------------+ | |
  LAN91C111    | | BANK	       | RESERVED    | | |
	       | |- - - - - - -|- - - - - - -| |  > na_lan91c111_size
	       | | RPCR	       | MIR	     | | |   = 0x00010000
	       | |- - - - - - -|- - - - - - -| | |
	       | | COUNTER     | RCR	     | | |
	       | |- - - - - - -|- - - - - - -| | |
	       | | EPH STATUS  | TCR	     | | |
	       | +---------------------------+ | |
  0x00910300 --+--LAN91C111_REGISTERS_OFFSET---| |
	       |	      gap	       | /
  0x00910000 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_LAN0_BASE
	       |			       |
	       :	      gap	       :
	       :			       :

- - - - - - - - - - -  external memory 1  - - - - - - - - - - - - - - - - - - -

	       :			       :
	       :	      gap	       :
	       |			       |
  0x00900000 ---32-----------16|15------------0-
  0x00900000 --+32-----------16|15------------0+
	       |	       :	       | \ \
	       |	       :	       | | |
	       |	       :	       | |  > CONFIG_SYS_NIOS_CPU_VEC_SIZE
	       |	       :	       | | |   = 0x00000100
	       |	       :	       | | /
  0x008fff00   |- - - - - - - -:- - - - - - - -+-|- CONFIG_SYS_NIOS_CPU_VEC_BASE
  0x008fff00   |- - - - - - - -:- - - - - - - -+-|- CONFIG_SYS_NIOS_CPU_STACK
	       |	       :	       | | \
	       |	       :	       | | |
	       |	       :	       | |  > stack area
	       |	       :	       | | |
	       |	       :	       | | V
	       |	       :	       | |
  SRAM	       |	       :	       |  > CONFIG_SYS_NIOS_CPU_SRAM_SIZE
	       |	       :	       | |   = 0x00100000
	       |	       :	       | /
  0x00800000 ---32-----------16|15------------0-    CONFIG_SYS_NIOS_CPU_SRAM_BASE
  0x00800000 ---8-------------4|3-------------0-
	       |  sector 127		       | \
    + 0x7f0000 |- - - - - - - - - - - - - - - -| |
	       |	       :	       | |
  Flash	       |-   -	-   -  :  -   -	  -   -|  > CONFIG_SYS_NIOS_CPU_FLASH_SIZE
	       |  sector 1     :	       | |   = 0x00800000
    + 0x010000 |- - - - - - - - - - - - - - - -| |
	       |  sector 0 (size = 0x10000)    | /
  0x00000000 ---8-------------4|3-------------0-    CONFIG_SYS_NIOS_CPU_FLASH_BASE


===============================================================================
	F L A S H   M E M O R Y	  A L L O C A T I O N
===============================================================================

  0x00800000 ---8-------------4|3-------------0-
	       |	       :	       | \
  SAFE	       |	       :	       |  > 1 MByte
  FPGA conf.   |	       :	       | /    (NOT usable by software)
  0x00700000 --+- - - - - - - -:- - - - - - - -+-
	       |	       :	       | \
  USER	       |	       :	       |  > 1 MByte
  FPGA conf.   |	       :	       | /    (NOT usable by software)
  0x00600000 --+- - - - - - - -:- - - - - - - -+-
	       |	       :	       | \
	       |	       :	       | |
  WEB pages    |	       :	       |  > 2 MByte
	       |	       :	       | |    (provisory usable)
	       |	       :	       | /
  0x00400000 --+- - - - - - - -:- - - - - - - -+-
	       |	       :	       | \
	       |	       :	       | |
	       |	       :	       | |
	       |	       :	       |  > 4 MByte free for use
	       |	       :	       | |
  0x00040000 --+- - - - - - - -:- - - - - - - -+-|- u-boot _start()
	       |	       :	       | /
  0x00000000   |- - - - - - - -:- - - - - - - -+- - u-boot environment
  0x00000000 ---8-------------4|3-------------0-


===============================================================================
	R E F E R E N C E S
===============================================================================
[1]	http://www.altera.com/literature/manual/mnl_nios_board_cyclone_1c20.pdf
[2]	http://www.altera.com/literature/ds/ds_nios_uart.pdf
[3]	http://www.altera.com/literature/ds/ds_nios_timer.pdf
[4]	http://www.altera.com/literature/ds/ds_nios_pio.pdf
[5]	http://www.altera.com/literature/ds/ds_nios_asmi.pdf
	http://www.altera.com/literature/wp/wp_epcs_cyc.pdf
[6]	http://www.opencores.org/projects/ata/
	http://www.t13.org/index.html


===============================================================================
Stephan Linz <linz@li-pro.net>