diff options
Diffstat (limited to 'arch/arm/kvm/init.S')
| -rw-r--r-- | arch/arm/kvm/init.S | 51 |
1 files changed, 43 insertions, 8 deletions
diff --git a/arch/arm/kvm/init.S b/arch/arm/kvm/init.S index bf89c919efc1..570ed4a9c261 100644 --- a/arch/arm/kvm/init.S +++ b/arch/arm/kvm/init.S @@ -23,6 +23,7 @@ #include <asm/kvm_asm.h> #include <asm/kvm_arm.h> #include <asm/kvm_mmu.h> +#include <asm/virt.h> /******************************************************************** * Hypervisor initialization @@ -39,6 +40,10 @@ * - 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 @@ -58,6 +63,10 @@ __kvm_hyp_init: 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 @@ -112,20 +121,46 @@ __do_hyp_init: eret - @ r0 : stub vectors address -ENTRY(__kvm_hyp_reset) +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 r2, =(HSCTLR_M | HSCTLR_A | HSCTLR_C | HSCTLR_I) - bic r1, r1, r2 + 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 */ - mcr p15, 4, r0, c12, c0, 0 @ HVBAR - isb + /* + * 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_hyp_reset) +ENDPROC(__kvm_handle_stub_hvc) .ltorg |