uboot/doc/README.m68k
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   2U-Boot for Motorola M68K
   3
   4====================================================================
   5History
   6
   7August 08,2005;         Jens Scharsig <esw@bus-elektronik.de>
   8                        MCF5282 implementation without preloader
   9January 12, 2004;       <josef.baumgartner@telex.de>
  10====================================================================
  11
  12This file contains status information for the port of U-Boot to the
  13Motorola M68K series of CPUs.
  14
  151. OVERVIEW
  16-----------
  17Bernhard Kuhn ported U-Boot 0.4.0 to the Motorola Coldfire
  18architecture. The patches of Bernhard support the MCF5272 and
  19MCF5282. A great disadvantage of these patches was that they needed
  20a pre-bootloader to start U-Boot. Because of this, a new port was
  21created which no longer needs a first stage booter.
  22
  23Although this port is intended to cover all M68k processors, only
  24the parts for the Motorola Coldfire MCF5272 and MCF5282 are
  25implemented at the moment. Additional CPUs and boards will be
  26hopefully added soon!
  27
  28
  292. SUPPORTED CPUs
  30-----------------
  31
  322.1 Motorola Coldfire MCF5272
  33-----------------------------
  34CPU specific code is located in: arch/m68k/cpu/mcf52x2
  35
  36
  372.1 Motorola Coldfire MCF5282
  38-----------------------------
  39CPU specific code is located in: arch/m68k/cpu/mcf52x2
  40
  41The MCF5282 Port no longer needs a preloader and can place in external or
  42internal FLASH.
  43
  44
  453. SUPPORTED BOARDs
  46-------------------
  47
  483.1 Motorola M5272C3 EVB
  49------------------------
  50Board specific code is located in: board/m5272c3
  51
  52To configure the board, type: make M5272C3_config
  53
  54U-Boot Memory Map:
  55------------------
  560xffe00000 - 0xffe3ffff         U-Boot
  570xffe04000 - 0xffe05fff         environment (embedded in U-Boot!)
  580xffe40000 - 0xffffffff         free for linux/applications
  59
  60
  613.2 Motorola M5282 EVB
  62------------------------
  63Board specific code is located in: board/m5282evb
  64
  65To configure the board, type: make M5272C3_config
  66
  67At the moment the code isn't fully implemented and still needs a pre-loader!
  68The preloader must initialize the processor and then start U-Boot. The board
  69must be configured for a pre-loader (see 4.1)
  70
  71For the preloader, please see
  72http://mailman.uclinux.org/pipermail/uclinux-dev/2003-December/023384.html
  73
  74U-Boot is configured to run at 0x20000 at default. This can be configured by
  75change CONFIG_SYS_TEXT_BASE in board/m5282evb/config.mk and CONFIG_SYS_MONITOR_BASE in
  76include/configs/M5282EVB.h.
  77
  783.2 BuS EB+MCF-EV123
  79---------------------
  80
  81Board specific code is located in: board/bus/EB+MCF-EV123
  82
  83To configure the board, type:
  84
  85make EB+MCF-EV123_config                for external FLASH
  86make EB+MCF-EV123_internal_config       for internal FLASH
  87
  88
  894. CONFIGURATION OPTIONS/SETTINGS
  90----------------------------------
  91
  924.1 Configuration to use a pre-loader
  93-------------------------------------
  94If U-Boot should be loaded to RAM and started by a pre-loader
  95CONFIG_MONITOR_IS_IN_RAM must be defined. If it is defined the
  96initial vector table and basic processor initialization will not
  97be compiled in. The start address of U-Boot must be adjusted in
  98the boards config header file (CONFIG_SYS_MONITOR_BASE) and Makefile
  99(CONFIG_SYS_TEXT_BASE) to the load address.
 100
 1014.1 MCF5272 specific Options/Settings
 102-------------------------------------
 103
 104CONFIG_MCF52x2  -- defined for all MCF52x2 CPUs
 105CONFIG_M5272    -- defined for all Motorola MCF5272 CPUs
 106
 107CONFIG_MONITOR_IS_IN_RAM
 108                -- defined if U-Boot is loaded by a pre-loader
 109
 110CONFIG_SYS_MBAR -- defines the base address of the MCF5272 configuration registers
 111CONFIG_SYS_INIT_RAM_ADDR
 112                -- defines the base address of the MCF5272 internal SRAM
 113CONFIG_SYS_ENET_BD_BASE
 114                -- defines the base address of the FEC buffer descriptors
 115
 116CONFIG_SYS_SCR          -- defines the contents of the System Configuration Register
 117CONFIG_SYS_SPR          -- defines the contents of the System Protection Register
 118CONFIG_SYS_BRx_PRELIM   -- defines the contents of the Chip Select Base Registers
 119CONFIG_SYS_ORx_PRELIM   -- defines the contents of the Chip Select Option Registers
 120
 121CONFIG_SYS_PxDDR        -- defines the contents of the Data Direction Registers
 122CONFIG_SYS_PxDAT        -- defines the contents of the Data Registers
 123CONFIG_SYS_PXCNT        -- defines the contents of the Port Configuration Registers
 124
 125
 1264.2 MCF5282 specific Options/Settings
 127-------------------------------------
 128
 129CONFIG_MCF52x2  -- defined for all MCF52x2 CPUs
 130CONFIG_M5282    -- defined for all Motorola MCF5282 CPUs
 131
 132CONFIG_MONITOR_IS_IN_RAM
 133                -- defined if U-Boot is loaded by a pre-loader
 134
 135CONFIG_SYS_MBAR -- defines the base address of the MCF5282 internal register space
 136CONFIG_SYS_INIT_RAM_ADDR
 137                -- defines the base address of the MCF5282 internal SRAM
 138CONFIG_SYS_INT_FLASH_BASE
 139                -- defines the base address of the MCF5282 internal Flash memory
 140CONFIG_SYS_ENET_BD_BASE
 141                -- defines the base address of the FEC buffer descriptors
 142
 143CONFIG_SYS_MFD
 144                -- defines the PLL Multiplication Factor Devider
 145                   (see table 9-4 of MCF user manual)
 146CONFIG_SYS_RFD          -- defines the PLL Reduce Frecuency Devider
 147                   (see table 9-4 of MCF user manual)
 148
 149CONFIG_SYS_CSx_BASE     -- defines the base address of chip select x
 150CONFIG_SYS_CSx_SIZE     -- defines the memory size (address range) of chip select x
 151CONFIG_SYS_CSx_WIDTH    -- defines the bus with of chip select x
 152CONFIG_SYS_CSx_RO       -- if set to 0 chip select x is read/wirte
 153                        else chipselct is read only
 154CONFIG_SYS_CSx_WS       -- defines the number of wait states  of chip select x
 155
 156CONFIG_SYS_PxDDR        -- defines the contents of the Data Direction Registers
 157CONFIG_SYS_PxDAT        -- defines the contents of the Data Registers
 158CONFIG_SYS_PXCNT        -- defines the contents of the Port Configuration Registers
 159
 160CONFIG_SYS_PxPAR        -- defines the function of ports
 161
 162
 1635. COMPILER
 164-----------
 165To create U-Boot the gcc-2.95.3 compiler set (m68k-elf-20030314) from uClinux.org was used.
 166You can download it from: http://www.uclinux.org/pub/uClinux/m68k-elf-tools/
 167