Overview

This is the Linux BSP (Board Support Package) for the Emcraft Systems Kinetis K70/K61 System-On-Module (SOM) Starter Kit.

The BSP provides a software development environment for evaluation and development of Linux (uClinux) on the Cortex-M4 processor core of the Kinetis microcontroller using the Emcraft Systems Kinetis SOM Starter Kit as a hardware platform.

Supported Features

The following list summarizes the features and capabilities of this release of the Kinetis SOM Starter Kit BSP:

• U-Boot firmware:
  • U-Boot v2010.03;
  • Target initialization from power-on / reset;
  • Runs from the internal eNVM and internal SRAM (no external memory required for standalone operation);
  • Serial console;
  • Ethernet driver for loading images to the target;
  • Serial driver for loading images to the target;
  • Device driver for built-in Flash (eNVM) and self-upgrade capability;
  • Device driver for storing environment and Linux images in external Flash;
  • Autoboot feature, allowing boot of OS images from Flash or other storage with no operator intervention;
  • Persistent environment in Flash for customization of target operation;
  • Sophisticated command interface for maintenance and development of the target.
• Linux:
  • uClinux kernel v2.6.33;
  • Boot from compressed and uncompressed images;
  • Ability to run critical kernel code from integrated Flash of Kinetis;
  • Serial device driver and Linux console;
  • Ethernet device driver and TCP/IP stack, ping, NFS, Telnet, FTP, NTPD, etc.);
  • busybox v1.17;
  • POSIX pthreads;
  • Hardened exception handling; an exception triggered by a process affects only the offending process;
  • Loadable kernel modules;
  • Support for the hardware FPU;
  • Secure shell (ssh) daemon;
  • Web server;
  • MTD-based Flash partitioning and persistent JFFS2 Flash file system for external Flash;
  • SDHC Card device driver;
  • Framebuffer device driver;
  • Touchscreen device driver;
  • GPIO device driver;
  • RTC device driver;
  • ADC device driver;
  • Device driver for the USB HS host interface;
  • Device driver for the USB FS host interface;
  • Device driver for the SPI interface.
• Development tools:
  • ARMv7-optimized GNU toolchain from CodeSourcery (2010q1) is used for development of U-Boot, Linux and user-space applications (toolchain must be downloaded separately from the CodeSourcery web site);
  • Cross GDB for debugging user-space applications;
  • mkimage tool used by the Linux kernel build process to create a Linux image bootable by U-Boot.
• Development environment:
  • Linux-hosted cross-development environment;
  • Development of multiple projects (embedded applications) from a single installation;
  • hello sample project ("Hello, world!" single-process configuration);
  • networking sample project (basic shell, networking, USB, and Flash management tools demonstration);
  • developer sample project (template project that can be used to jump-start development of custom user-space applications and loadable kernel modules).

New and Changed Features

This section lists new and changed features of this release:

1. Resolve defect: Linux: Marking bad blocks on NAND doesn't work.
   ID: RT 108775.
2. Resolve defect: U-Boot: Fixed error in NAND driver - ECC soft errors didn't not correct.
   ID: RT 108546.
3. Support hardware FPU code in pthreaded applications in uClinux on Cortex-M.
   ID: RT 110109.
4. Add support for low-power mode to the 8081 PHY device driver (put device into the slow oscillator mode).
   ID: RT 112915.

Known Problems & Limitations

This section lists known problems and limitations of this release:

1. CONFIG_KERNEL_IN_ENVM requires disabling CONFIG_ARM_UNWIND and CONFIG_EARLY_PRINTK.
   ID: RT 74683.
   Workaround: When enabling CONFIG_KERNEL_IN_ENVM in the kernel, disable CONFIG_ARM_UNWIND and CONFIG_EARLY_PRINTK.
2. Enabling CONFIG_USB_EHCI_HCD disables data cache in Linux Kinetis.
   ID: RT 106727
   Workaround: If data cache is required, disable CONFIG_USB_EHCI_HCD and CONFIG_USB_EHCI_MXC in the kernel configuration.
3. The Emcraft Systems TWR-K70-SOM-BSB Hardware Architecture document
   (twr-k70-som-bsb-ha.pdf) is not included in this release of the product. The document will be made available in the next release.