u-boot/arch
Miao Yan 417576c2f1 x86: Add a 'pause' instruction in __udelay() for QEMU target
When running SMP configuration on QEMU (tcg mode, no kvm), there is
a busy loop in start_aps(), calling udelay(), that waits for APs to
show up online. However, there is a chance that VCPU1 will be timeout
waiting, IOW the secondary VCPUs haven't started their execution yet.

This patch adds a 'pause' instruction in __udelay() only for QEMU
target, to give other VCPUs a chance to run. When QEMU sees the
'pause' instruction, it will yeild the execution to other CPUs.

Signed-off-by: Miao Yan <yanmiaobest@gmail.com>
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
2015-08-05 08:42:38 -06:00
..
arc arc: significant cache rework 2015-07-01 17:17:27 +03:00
arm armv8/lsch3/config: Define USB XHCI controller base address for LS2085A 2015-08-03 12:06:39 -07:00
avr32 avr32: delete ancient board.c 2015-06-10 14:03:26 +02:00
blackfin arch: Make board selection choices optional 2015-05-12 18:10:02 -04:00
m68k arch: Make board selection choices optional 2015-05-12 18:10:02 -04:00
microblaze arch: Make board selection choices optional 2015-05-12 18:10:02 -04:00
mips MIPS: change 'extern inline' to 'static inline' 2015-07-02 11:29:33 +02:00
nds32 arch: Make board selection choices optional 2015-05-12 18:10:02 -04:00
nios2 arch: Make board selection choices optional 2015-05-12 18:10:02 -04:00
openrisc arch: Make board selection choices optional 2015-05-12 18:10:02 -04:00
powerpc Merge branch 'master' of git://git.denx.de/u-boot-mpc85xx 2015-07-31 20:16:21 -04:00
sandbox dm: test: Add a size to each reg property 2015-07-21 17:39:33 -06:00
sh Move default y configs out of arch/board Kconfig 2015-06-25 22:17:55 -04:00
sparc arch: Make board selection choices optional 2015-05-12 18:10:02 -04:00
x86 x86: Add a 'pause' instruction in __udelay() for QEMU target 2015-08-05 08:42:38 -06:00
.gitignore .gitignore: drop include/asm/proc from ignore pattern 2014-06-19 11:18:54 -04:00
Kconfig kbuild: create symbolic link only for ARM, AVR32, SPARC, PowerPC, x86 2015-07-27 15:02:00 -04:00