Every time a PC is switched on the Basic Input Output System, BIOS needs to be configured before the operating system is started. It’s necessary among other things to detect new hardware introduced in the system, for example an additional hard disk drive or a new screen. It takes time, but is crucial, at least in applications like desktops and servers.
When it comes to embedded applications it’s often another thing.
– The difference is that a typical embedded application doesn’t change over time. It’s a “sealed box” with the same configuration always, says Neil Stroud, Field Applications Engineer at Intel® Sweden AB. So why go through all that hassle of the BIOS checking what’s there and configuring every time?
In comparison with BIOS a boot loader is a basic boot solution offering a significantly faster start-up procedure since the boot loader is developed specifically for the application, adapted to one well-defined hardware configuration, one operating system and only one version of it. Boot loaders aren’t delayed by requirements to handle multiple operating systems, in various versions in hardware which can be expected to change from one boot to the other.
Bootloader versus BIOS
BIOS enables X86-processor platforms to support a range of intelligent hardware features such as Intel® Active Management Technology and Intel® Trusted Execution Technology. A BIOS adaptation certainly is a possibility to reduce boot time. Not all embedded applications require that level of flexibility and functionality however, and may in general benefit strongly from the more straight-forward and simple boot loader.
The possibility to use boot loaders has existed previously, at least in theory. In practice development of boot loaders for X86 processor platforms have been too complicated and the information required about the processor platforms hasn’t always been available.
Intel® has addressed this issue by the introduction of the Intel® Boot Loader Development Kit (Intel® BLDK) for embedded designs based on Intel® Atom™ processors. Neil Stroud has had the opportunity to present the possibilities to customers. Judging from the reactions one advantage stands out as the more appealing to customers.
– They say the boot time especially. The boot time is considered such an important aspect and boot loaders can save you thirty seconds easily, depending on what the application is, says Neil Stroud.
Faster boot time
The boot time is faster, much faster, compared to using standard BIOS. Another advantage is also positively received among customers, according to Neil Stroud. It’s about being in control, in control of your own destiny, as he puts it. The traditionally used BIOS is supplied by a third party vendor and is generally not easily accessible in source code.
The Intel® BLDK opens up for more transparency since the intellectual property, IP is less restricted. OEM customers will probably not develop boot loaders from scratch since board support packages including boot loaders are likely to be supplied with COM modules and motherboards. In this sense there are similarities to embedded applications using BIOS.
However there is a possibility for a wide range of developers to view, understand and even make adjustments to the final boot loader through the transparency and ease of use of the Intel® BLDK.
– To be able to fine tune for your specific platform is obviously of big value to many, many customers.
With transparency, understanding and control comes possibilities, for instance to decrease power consumption.
– So if you are not using a specific block within the device, merely power down or run in sleep mode. You can configure that in the boot loader, says Neil Stroud.
Intel® boot loader technology and Intel® Atom™ processors fit perfectly for instance in applications such as set-top boxes and industrial automation. The US Food and Drug Administration, FDA states that medical devices for use in emergency rooms must be fully operational in less than thirty seconds. Intel® boot loader technology are most definitely going to play an important role in meeting that requirement to make sure that vital seconds aren’t lost in emergency care.
Major BIOS vendors cooperate
In-Vehicle Infotainment is one of the obvious application areas, and Neil Stroud’s favorite, for illustrating the advantages in deploying boot loaders and Intel® Atom™ processors. As the key is turned and the engine is started the driver expects much faster start-up of the computer system than the ten, twenty or even thirty seconds that are common to the PC world.
– The start-up time has to be half a second, almost instant on.
BIOS vendors don’t, as one could imagine, consider Intel® boot loader technology to be a threat, quite the contrary. Major vendors are actively cooperating with Intel®.
– They are actually supporting us since it can drive business for them as well. They can offer services on top of this.
Intel® BLDK itself is free but development of boot loaders requires resources and skills. It’s an increased cost in comparison with BIOS. On the other hand there is always a price to pay to use third-party BIOS, in the form of license fees and NRE costs for adaptations to the BIOS by the vendor. All other aspects set aside the financial side of boot loader versus BIOS needs to be estimated and decided upon for each project or product individually.
BLDK – Features and Benefits
• Intel® Atom™ processor E6xx series with Intel® Platform Controller Hub EG20T in use for instance in the Hectronic H6055 Qseven module.
• Additional Intel® platforms will be supported in the future.
Provides basic CPU, memory and chipset initialization required for fixed-function embedded systems.
Allows boot to operating system installations on a variety of system devices and interfaces, including serial ATA, Compact Flash, Secure Digital card, USB, firmware hub, serial peripheral interface, and network boot through PXE interface.
Support for boot to UEFI-compliant Linux operating system boot loaders, as well as interfaces to boot Wind River VxWorks, Microsoft Windows CE 6.0 and Microsoft Windows Embedded Compact 7.
Microsoft Windows-based development environment and tool set supports the Intel® BLDK IDE and tools, allowing binary modification of many configuration options in the system firmware.
Provides optimized display and splash screen support utilizing the UEFI-compliant Graphics Output Protocol driver from the Intel® Embedded Media and Graphics Driver.
Boot Speed and Size
Baseline boot speed under three seconds, and capable of firmware image sizes well under 1 MB.
Network File Transfer
TCP/IP file transfer capability for implementation features such as remote firmware upgrade or firmware recovery.
Power management support is compliant with Advanced Configuration and Power Interface (ACPI) specification version 3.0.
Support for the Intel® UEFI Development Kit Debugger Tool enables faster and easier debug of Intel® processor-based platforms.
Supports the UEFI 2.0 Shell environment for simple operation and diagnostics.