u-boot-brain/arch/x86
Bin Meng 5750e5e29a x86: quark: Optimize MRC execution time
Intel Quark SoC has a low end x86 processor with only 400MHz
frequency. Currently it takes about 15 seconds for U-Boot to
boot to shell and the most time consuming part is with MRC,
which is about 12 seconds. MRC programs lots of registers on
the SoC internal message bus indirectly accessed via pci bus.

To speed up the boot, create an optimized version of pci config
read/write dword routines which directly operate on PCI I/O ports.
These two routines are inlined to provide better performance too.
Now it only takes about 3 seconds to finish MRC, which is really
fast (4 times faster than before).

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-09-09 07:48:03 -06:00
..
cpu x86: quark: Optimize MRC execution time 2015-09-09 07:48:03 -06:00
dts x86: panther: Add PCI and video configuration 2015-09-09 07:48:03 -06:00
include/asm x86: quark: Optimize MRC execution time 2015-09-09 07:48:03 -06:00
lib x86: Generate a valid ACPI table 2015-08-26 07:54:13 -07:00
config.mk efi: Add 64-bit payload support 2015-08-05 08:44:07 -06:00
Kconfig x86: Generate a valid ACPI table 2015-08-26 07:54:13 -07:00
Makefile x86: Add support for U-Boot as an EFI application 2015-08-05 08:44:06 -06:00