From 955d8dc3ee555e9320fabbeab0969f9cf7660f9d Mon Sep 17 00:00:00 2001 From: James Hogan Date: Tue, 14 Mar 2017 10:15:14 +0000 Subject: KVM: MIPS: Implement HYPCALL emulation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Emulate the HYPCALL instruction added in the VZ ASE and used by the MIPS paravirtualised guest support that is already merged. The new hypcall.c handles arguments and the return value. No actual hypercalls are yet supported, but this still allows us to safely step over hypercalls and set an error code in the return value for forward compatibility. Non-zero HYPCALL codes are not handled. We also document the hypercall ABI which asm/kvm_para.h uses. Signed-off-by: James Hogan Acked-by: Ralf Baechle Cc: Paolo Bonzini Cc: "Radim Krčmář" Cc: Andreas Herrmann Cc: David Daney Cc: Jonathan Corbet Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: linux-doc@vger.kernel.org --- Documentation/virtual/kvm/hypercalls.txt | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'Documentation/virtual') diff --git a/Documentation/virtual/kvm/hypercalls.txt b/Documentation/virtual/kvm/hypercalls.txt index feaaa634f154..a890529c63ed 100644 --- a/Documentation/virtual/kvm/hypercalls.txt +++ b/Documentation/virtual/kvm/hypercalls.txt @@ -28,6 +28,11 @@ S390: property inside the device tree's /hypervisor node. For more information refer to Documentation/virtual/kvm/ppc-pv.txt +MIPS: + KVM hypercalls use the HYPCALL instruction with code 0 and the hypercall + number in $2 (v0). Up to four arguments may be placed in $4-$7 (a0-a3) and + the return value is placed in $2 (v0). + KVM Hypercalls Documentation =========================== The template for each hypercall is: -- cgit v1.2.3-59-g8ed1b