1 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: cpu/mcf52x2 35 36 372.1 Motorola Coldfire MCF5282 38----------------------------- 39CPU specific code is located in: 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 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(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 addres 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 addres 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