Commit graph

10 commits

Author SHA1 Message Date
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
Bin Meng
3ba6a0f4f6 x86: Allow a hardcoded TSC frequency provided by Kconfig
By default U-Boot automatically calibrates TSC running frequency via
MSR and PIT. The calibration may not work on every x86 processor, so
a new Kconfig option CONFIG_TSC_CALIBRATION_BYPASS is introduced to
allow bypassing the calibration and assign a hardcoded TSC frequency
CONFIG_TSC_FREQ_IN_MHZ.

Normally the bypass should be turned on in a simulation environment
like qemu.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-01-13 07:25:02 -08:00
Simon Glass
5c1b685e46 x86: Allow timer calibration to work on ivybridge
Unfortunately MSR_FSB_FREQ is not available on this CPU, and the PIT method
seems to take up to 50ms which is much too long.

For this CPU we know the frequency, so add another special case for now.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2014-11-21 07:24:12 +01:00
Bin Meng
258b1357c6 x86: Save TSC frequency in the global data
Return the saved TSC frequency in get_tbclk_mhz().

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
2014-11-21 07:24:10 +01:00
Bin Meng
80de049561 x86: Add quick TSC calibration via PIT
Use the same way that Linux does for quick TSC calibration via PIT
when calibration via MSR fails.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
2014-11-21 07:24:10 +01:00
Bin Meng
076bb44b0e x86: Do TSC MSR calibration only for known/supported CPUs
Using MSR_PLATFORM_INFO (0xCE) to calibrate TSR will cause #GP on
processors which do not have this MSR. Instead only doing the MSR
calibration for known/supported CPUs.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
2014-11-21 07:24:10 +01:00
Wolfgang Denk
1a4596601f Add GPL-2.0+ SPDX-License-Identifier to source files
Signed-off-by: Wolfgang Denk <wd@denx.de>
[trini: Fixup common/cmd_io.c]
Signed-off-by: Tom Rini <trini@ti.com>
2013-07-24 09:44:38 -04:00
Simon Glass
d8819f94d5 x86: Support tracing function
Some changes are needed to x86 timer functions to support tracing. Add
these so that the feature works correctly.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-06-26 10:18:56 -04:00
Simon Glass
d0b6f247a1 x86: Re-enable PCAT timer 2 for beeping
While we don't want PCAT timers for timing, we want timer 2 so that we can
still make a beep. Re-purpose the PCAT driver for this, and enable it in
coreboot.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-05-13 13:33:21 -07:00
Simon Glass
e761ecdbb8 x86: Add TSC timer
This timer runs at a rate that can be calculated, well over 100MHz. It is
ideal for accurate timing and does not need interrupt servicing.

Tidy up some old broken and unneeded implementations at the same time.

To provide a consistent view of boot time, we use the same time
base as coreboot. Use the base timestamp supplied by coreboot
as U-Boot's base time.

Signed-off-by: Simon Glass <sjg@chromium.org>base
Signed-off-by: Simon Glass <sjg@chromium.org>
2013-05-13 13:33:21 -07:00