c513835c4f
We should also deal with change of the imask bit, or we will lose timer
interrupt if the timer expires before the guest kernel unmasks the bit.
More precisely, consider the following common pattern in timer interrupt
handling:
1. Set the interrupt mask bit (CNTV_CTL.IMASK)
2. Reprogram the downcounter (CNTV_TVAL) for the next interrupt
3. Clear the interrupt mask bit (CNTV_CTL.IMASK)
The timer can expires between step 2 & 3 if the value programmed in step
2 is small enough, and this seems very likely to happen in KVM mode. If
we don't check for timer expiration right after unmasking, we will miss
the only chance to inject the interrupt.
JIRA: https://gem5.atlassian.net/browse/GEM5-663
Change-Id: I75e8253bb78d15ae72cb985ed132f896d8e92ca6
Signed-off-by: Hsuan Hsu <hsuan.hsu@mediatek.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/30918
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This is the gem5 simulator. The main website can be found at http://www.gem5.org A good starting point is http://www.gem5.org/about, and for more information about building the simulator and getting started please see http://www.gem5.org/documentation and http://www.gem5.org/documentation/learning_gem5/introduction. To build gem5, you will need the following software: g++ or clang, Python (gem5 links in the Python interpreter), SCons, SWIG, zlib, m4, and lastly protobuf if you want trace capture and playback support. Please see http://www.gem5.org/documentation/general_docs/building for more details concerning the minimum versions of the aforementioned tools. Once you have all dependencies resolved, type 'scons build/<ARCH>/gem5.opt' where ARCH is one of ARM, NULL, MIPS, POWER, SPARC, or X86. This will build an optimized version of the gem5 binary (gem5.opt) for the the specified architecture. See http://www.gem5.org/documentation/general_docs/building for more details and options. The basic source release includes these subdirectories: - configs: example simulation configuration scripts - ext: less-common external packages needed to build gem5 - src: source code of the gem5 simulator - system: source for some optional system software for simulated systems - tests: regression tests - util: useful utility programs and files To run full-system simulations, you will need compiled system firmware (console and PALcode for Alpha), kernel binaries and one or more disk images. If you have questions, please send mail to gem5-users@gem5.org Enjoy using gem5 and please share your modifications and extensions.