From mboxrd@z Thu Jan 1 00:00:00 1970 From: panand@redhat.com (Pratyush Anand) Date: Fri, 6 Jan 2017 09:01:56 +0530 Subject: [PATCH V2 0/2] kexec-tools: arm64: Enable D-cache in purgatory In-Reply-To: References: Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi James and All, Any feedback/review comment on it? ~Pratyush On Monday 19 December 2016 12:43 PM, Pratyush Anand wrote: > It takes more that 2 minutes to verify SHA in purgatory when vmlinuz image > is around 13MB and initramfs is around 30MB. It takes more than 20 second > even when we have -O2 optimization enabled. However, if dcache is enabled > during purgatory execution then, it takes just a second in SHA > verification. > > Therefore, these patches adds support for dcache enabling facility during > purgatory execution. > > Although I have simplified the logic a bit now, however I understand that > there are reservations for introducing this complexity for gaining few > seconding of execution time during kexec or crash reboot. But, I believe > if d-cache enabling code is stable enough then there should not be any > hindrances to accept it. So, please give it a try with your platform and > let me know if you see any issue or it does not work. I am still open to > improve it further if needed. > > Changes since V1: > - Moved page table creation logic from purgatory to kexec code. > - Only 4K page table is supported, with 48 bit VA and 2M block size > - if platform supports a 4K page size, then D-cache is always > enabled now. > > Pratyush Anand (2): > kexec: arm64: create identity page table to be used in purgatory > arm64: enable d-cache support during purgatory sha verification > > kexec/arch/arm64/kexec-arm64.c | 152 ++++++++++++++++++ > purgatory/arch/arm64/Makefile | 1 + > purgatory/arch/arm64/cache.S | 281 +++++++++++++++++++++++++++++++++ > purgatory/arch/arm64/purgatory-arm64.c | 5 + > 4 files changed, 439 insertions(+) > create mode 100644 purgatory/arch/arm64/cache.S >