From 03a0331c8c715c73d877aba8c542a60b13f70ed0 Mon Sep 17 00:00:00 2001 From: Sanjay Lal Date: Wed, 21 Nov 2012 18:34:06 -0800 Subject: KVM/MIPS32: Release notes and KVM module Makefile Signed-off-by: Sanjay Lal Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Ralf Baechle --- arch/mips/kvm/00README.txt | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 arch/mips/kvm/00README.txt (limited to 'arch/mips/kvm/00README.txt') diff --git a/arch/mips/kvm/00README.txt b/arch/mips/kvm/00README.txt new file mode 100644 index 00000000000..51617e481aa --- /dev/null +++ b/arch/mips/kvm/00README.txt @@ -0,0 +1,31 @@ +KVM/MIPS Trap & Emulate Release Notes +===================================== + +(1) KVM/MIPS should support MIPS32R2 and beyond. It has been tested on the following platforms: + Malta Board with FPGA based 34K + Sigma Designs TangoX board with a 24K based 8654 SoC. + Malta Board with 74K @ 1GHz + +(2) Both Guest kernel and Guest Userspace execute in UM. + Guest User address space: 0x00000000 -> 0x40000000 + Guest Kernel Unmapped: 0x40000000 -> 0x60000000 + Guest Kernel Mapped: 0x60000000 -> 0x80000000 + + Guest Usermode virtual memory is limited to 1GB. + +(2) 16K Page Sizes: Both Host Kernel and Guest Kernel should have the same page size, currently at least 16K. + Note that due to cache aliasing issues, 4K page sizes are NOT supported. + +(3) No HugeTLB Support + Both the host kernel and Guest kernel should have the page size set to 16K. + This will be implemented in a future release. + +(4) KVM/MIPS does not have support for SMP Guests + Linux-3.7-rc2 based SMP guest hangs due to the following code sequence in the generated TLB handlers: + LL/TLBP/SC. Since the TLBP instruction causes a trap the reservation gets cleared + when we ERET back to the guest. This causes the guest to hang in an infinite loop. + This will be fixed in a future release. + +(5) Use Host FPU + Currently KVM/MIPS emulates a 24K CPU without a FPU. + This will be fixed in a future release -- cgit v1.2.3-70-g09d2