mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-28 08:05:26 +07:00
fa85e25dad
Now that the old code is long gone, we can remove all the weak attributes, as there is only one version of the code. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
170 lines
4.3 KiB
ArmAsm
170 lines
4.3 KiB
ArmAsm
/*
|
|
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
|
|
* Author: Christoffer Dall <c.dall@virtualopensystems.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License, version 2, as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/kvm_arm.h>
|
|
#include <asm/kvm_asm.h>
|
|
|
|
.arch_extension virt
|
|
|
|
.text
|
|
.pushsection .hyp.text, "ax"
|
|
|
|
.macro load_vcpu reg
|
|
mrc p15, 4, \reg, c13, c0, 2 @ HTPIDR
|
|
.endm
|
|
|
|
/********************************************************************
|
|
* Hypervisor exception vector and handlers
|
|
*
|
|
*
|
|
* The KVM/ARM Hypervisor ABI is defined as follows:
|
|
*
|
|
* Entry to Hyp mode from the host kernel will happen _only_ when an HVC
|
|
* instruction is issued since all traps are disabled when running the host
|
|
* kernel as per the Hyp-mode initialization at boot time.
|
|
*
|
|
* HVC instructions cause a trap to the vector page + offset 0x14 (see hyp_hvc
|
|
* below) when the HVC instruction is called from SVC mode (i.e. a guest or the
|
|
* host kernel) and they cause a trap to the vector page + offset 0x8 when HVC
|
|
* instructions are called from within Hyp-mode.
|
|
*
|
|
* Hyp-ABI: Calling HYP-mode functions from host (in SVC mode):
|
|
* Switching to Hyp mode is done through a simple HVC #0 instruction. The
|
|
* exception vector code will check that the HVC comes from VMID==0.
|
|
* - r0 contains a pointer to a HYP function
|
|
* - r1, r2, and r3 contain arguments to the above function.
|
|
* - The HYP function will be called with its arguments in r0, r1 and r2.
|
|
* On HYP function return, we return directly to SVC.
|
|
*
|
|
* Note that the above is used to execute code in Hyp-mode from a host-kernel
|
|
* point of view, and is a different concept from performing a world-switch and
|
|
* executing guest code SVC mode (with a VMID != 0).
|
|
*/
|
|
|
|
.align 5
|
|
__kvm_hyp_vector:
|
|
.global __kvm_hyp_vector
|
|
|
|
@ Hyp-mode exception vector
|
|
W(b) hyp_reset
|
|
W(b) hyp_undef
|
|
W(b) hyp_svc
|
|
W(b) hyp_pabt
|
|
W(b) hyp_dabt
|
|
W(b) hyp_hvc
|
|
W(b) hyp_irq
|
|
W(b) hyp_fiq
|
|
|
|
.macro invalid_vector label, cause
|
|
.align
|
|
\label: mov r0, #\cause
|
|
b __hyp_panic
|
|
.endm
|
|
|
|
invalid_vector hyp_reset ARM_EXCEPTION_RESET
|
|
invalid_vector hyp_undef ARM_EXCEPTION_UNDEFINED
|
|
invalid_vector hyp_svc ARM_EXCEPTION_SOFTWARE
|
|
invalid_vector hyp_pabt ARM_EXCEPTION_PREF_ABORT
|
|
invalid_vector hyp_dabt ARM_EXCEPTION_DATA_ABORT
|
|
invalid_vector hyp_fiq ARM_EXCEPTION_FIQ
|
|
|
|
ENTRY(__hyp_do_panic)
|
|
mrs lr, cpsr
|
|
bic lr, lr, #MODE_MASK
|
|
orr lr, lr, #SVC_MODE
|
|
THUMB( orr lr, lr, #PSR_T_BIT )
|
|
msr spsr_cxsf, lr
|
|
ldr lr, =panic
|
|
msr ELR_hyp, lr
|
|
ldr lr, =kvm_call_hyp
|
|
clrex
|
|
eret
|
|
ENDPROC(__hyp_do_panic)
|
|
|
|
hyp_hvc:
|
|
/*
|
|
* Getting here is either because of a trap from a guest,
|
|
* or from executing HVC from the host kernel, which means
|
|
* "do something in Hyp mode".
|
|
*/
|
|
push {r0, r1, r2}
|
|
|
|
@ Check syndrome register
|
|
mrc p15, 4, r1, c5, c2, 0 @ HSR
|
|
lsr r0, r1, #HSR_EC_SHIFT
|
|
cmp r0, #HSR_EC_HVC
|
|
bne guest_trap @ Not HVC instr.
|
|
|
|
/*
|
|
* Let's check if the HVC came from VMID 0 and allow simple
|
|
* switch to Hyp mode
|
|
*/
|
|
mrrc p15, 6, r0, r2, c2
|
|
lsr r2, r2, #16
|
|
and r2, r2, #0xff
|
|
cmp r2, #0
|
|
bne guest_trap @ Guest called HVC
|
|
|
|
/*
|
|
* Getting here means host called HVC, we shift parameters and branch
|
|
* to Hyp function.
|
|
*/
|
|
pop {r0, r1, r2}
|
|
|
|
/* Check for __hyp_get_vectors */
|
|
cmp r0, #-1
|
|
mrceq p15, 4, r0, c12, c0, 0 @ get HVBAR
|
|
beq 1f
|
|
|
|
push {lr}
|
|
|
|
mov lr, r0
|
|
mov r0, r1
|
|
mov r1, r2
|
|
mov r2, r3
|
|
|
|
THUMB( orr lr, #1)
|
|
blx lr @ Call the HYP function
|
|
|
|
pop {lr}
|
|
1: eret
|
|
|
|
guest_trap:
|
|
load_vcpu r0 @ Load VCPU pointer to r0
|
|
|
|
#ifdef CONFIG_VFPv3
|
|
@ Check for a VFP access
|
|
lsr r1, r1, #HSR_EC_SHIFT
|
|
cmp r1, #HSR_EC_CP_0_13
|
|
beq __vfp_guest_restore
|
|
#endif
|
|
|
|
mov r1, #ARM_EXCEPTION_HVC
|
|
b __guest_exit
|
|
|
|
hyp_irq:
|
|
push {r0, r1, r2}
|
|
mov r1, #ARM_EXCEPTION_IRQ
|
|
load_vcpu r0 @ Load VCPU pointer to r0
|
|
b __guest_exit
|
|
|
|
.ltorg
|
|
|
|
.popsection
|