171 lines
4.3 KiB
ArmAsm
171 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/assembler.h>
|
|
#include <asm/unified.h>
|
|
#include <asm/asm-offsets.h>
|
|
#include <asm/kvm_asm.h>
|
|
#include <asm/kvm_arm.h>
|
|
#include <asm/kvm_mmu.h>
|
|
#include <asm/virt.h>
|
|
|
|
/********************************************************************
|
|
* Hypervisor initialization
|
|
* - should be called with:
|
|
* r0 = top of Hyp stack (kernel VA)
|
|
* r1 = pointer to hyp vectors
|
|
* r2,r3 = Hypervisor pgd pointer
|
|
*
|
|
* The init scenario is:
|
|
* - We jump in HYP with 3 parameters: runtime HYP pgd, runtime stack,
|
|
* runtime vectors
|
|
* - Invalidate TLBs
|
|
* - Set stack and vectors
|
|
* - Setup the page tables
|
|
* - Enable the MMU
|
|
* - Profit! (or eret, if you only care about the code).
|
|
*
|
|
* Another possibility is to get a HYP stub hypercall.
|
|
* We discriminate between the two by checking if r0 contains a value
|
|
* that is less than HVC_STUB_HCALL_NR.
|
|
*/
|
|
|
|
.text
|
|
.pushsection .hyp.idmap.text,"ax"
|
|
.align 5
|
|
__kvm_hyp_init:
|
|
.globl __kvm_hyp_init
|
|
|
|
@ Hyp-mode exception vector
|
|
W(b) .
|
|
W(b) .
|
|
W(b) .
|
|
W(b) .
|
|
W(b) .
|
|
W(b) __do_hyp_init
|
|
W(b) .
|
|
W(b) .
|
|
|
|
__do_hyp_init:
|
|
@ Check for a stub hypercall
|
|
cmp r0, #HVC_STUB_HCALL_NR
|
|
blo __kvm_handle_stub_hvc
|
|
|
|
@ Set stack pointer
|
|
mov sp, r0
|
|
|
|
@ Set HVBAR to point to the HYP vectors
|
|
mcr p15, 4, r1, c12, c0, 0 @ HVBAR
|
|
|
|
@ Set the HTTBR to point to the hypervisor PGD pointer passed
|
|
mcrr p15, 4, rr_lo_hi(r2, r3), c2
|
|
|
|
@ Set the HTCR and VTCR to the same shareability and cacheability
|
|
@ settings as the non-secure TTBCR and with T0SZ == 0.
|
|
mrc p15, 4, r0, c2, c0, 2 @ HTCR
|
|
ldr r2, =HTCR_MASK
|
|
bic r0, r0, r2
|
|
mrc p15, 0, r1, c2, c0, 2 @ TTBCR
|
|
and r1, r1, #(HTCR_MASK & ~TTBCR_T0SZ)
|
|
orr r0, r0, r1
|
|
mcr p15, 4, r0, c2, c0, 2 @ HTCR
|
|
|
|
@ Use the same memory attributes for hyp. accesses as the kernel
|
|
@ (copy MAIRx ro HMAIRx).
|
|
mrc p15, 0, r0, c10, c2, 0
|
|
mcr p15, 4, r0, c10, c2, 0
|
|
mrc p15, 0, r0, c10, c2, 1
|
|
mcr p15, 4, r0, c10, c2, 1
|
|
|
|
@ Invalidate the stale TLBs from Bootloader
|
|
mcr p15, 4, r0, c8, c7, 0 @ TLBIALLH
|
|
dsb ish
|
|
|
|
@ Set the HSCTLR to:
|
|
@ - ARM/THUMB exceptions: Kernel config (Thumb-2 kernel)
|
|
@ - Endianness: Kernel config
|
|
@ - Fast Interrupt Features: Kernel config
|
|
@ - Write permission implies XN: disabled
|
|
@ - Instruction cache: enabled
|
|
@ - Data/Unified cache: enabled
|
|
@ - Memory alignment checks: enabled
|
|
@ - MMU: enabled (this code must be run from an identity mapping)
|
|
mrc p15, 4, r0, c1, c0, 0 @ HSCR
|
|
ldr r2, =HSCTLR_MASK
|
|
bic r0, r0, r2
|
|
mrc p15, 0, r1, c1, c0, 0 @ SCTLR
|
|
ldr r2, =(HSCTLR_EE | HSCTLR_FI | HSCTLR_I | HSCTLR_C)
|
|
and r1, r1, r2
|
|
ARM( ldr r2, =(HSCTLR_M | HSCTLR_A) )
|
|
THUMB( ldr r2, =(HSCTLR_M | HSCTLR_A | HSCTLR_TE) )
|
|
orr r1, r1, r2
|
|
orr r0, r0, r1
|
|
mcr p15, 4, r0, c1, c0, 0 @ HSCR
|
|
isb
|
|
|
|
eret
|
|
|
|
ENTRY(__kvm_handle_stub_hvc)
|
|
cmp r0, #HVC_SOFT_RESTART
|
|
bne 1f
|
|
|
|
/* The target is expected in r1 */
|
|
msr ELR_hyp, r1
|
|
mrs r0, cpsr
|
|
bic r0, r0, #MODE_MASK
|
|
orr r0, r0, #HYP_MODE
|
|
THUMB( orr r0, r0, #PSR_T_BIT )
|
|
msr spsr_cxsf, r0
|
|
b reset
|
|
|
|
1: cmp r0, #HVC_RESET_VECTORS
|
|
bne 1f
|
|
|
|
reset:
|
|
/* We're now in idmap, disable MMU */
|
|
mrc p15, 4, r1, c1, c0, 0 @ HSCTLR
|
|
ldr r0, =(HSCTLR_M | HSCTLR_A | HSCTLR_C | HSCTLR_I)
|
|
bic r1, r1, r0
|
|
mcr p15, 4, r1, c1, c0, 0 @ HSCTLR
|
|
|
|
/*
|
|
* Install stub vectors, using ardb's VA->PA trick.
|
|
*/
|
|
0: adr r0, 0b @ PA(0)
|
|
movw r1, #:lower16:__hyp_stub_vectors - 0b @ VA(stub) - VA(0)
|
|
movt r1, #:upper16:__hyp_stub_vectors - 0b
|
|
add r1, r1, r0 @ PA(stub)
|
|
mcr p15, 4, r1, c12, c0, 0 @ HVBAR
|
|
b exit
|
|
|
|
1: ldr r0, =HVC_STUB_ERR
|
|
eret
|
|
|
|
exit:
|
|
mov r0, #0
|
|
eret
|
|
ENDPROC(__kvm_handle_stub_hvc)
|
|
|
|
.ltorg
|
|
|
|
.globl __kvm_hyp_init_end
|
|
__kvm_hyp_init_end:
|
|
|
|
.popsection
|