diff options
Diffstat (limited to 'arch/powerpc/kernel/kvm_emul.S')
| -rw-r--r-- | arch/powerpc/kernel/kvm_emul.S | 302 |
1 files changed, 302 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/kvm_emul.S b/arch/powerpc/kernel/kvm_emul.S new file mode 100644 index 00000000000..f2b1b2523e6 --- /dev/null +++ b/arch/powerpc/kernel/kvm_emul.S @@ -0,0 +1,302 @@ +/* + * 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. + * + * Copyright SUSE Linux Products GmbH 2010 + * + * Authors: Alexander Graf <agraf@suse.de> + */ + +#include <asm/ppc_asm.h> +#include <asm/kvm_asm.h> +#include <asm/reg.h> +#include <asm/page.h> +#include <asm/asm-offsets.h> + +/* Hypercall entry point. Will be patched with device tree instructions. */ + +.global kvm_hypercall_start +kvm_hypercall_start: + li r3, -1 + nop + nop + nop + blr + +#define KVM_MAGIC_PAGE (-4096) + +#ifdef CONFIG_64BIT +#define LL64(reg, offs, reg2) ld reg, (offs)(reg2) +#define STL64(reg, offs, reg2) std reg, (offs)(reg2) +#else +#define LL64(reg, offs, reg2) lwz reg, (offs + 4)(reg2) +#define STL64(reg, offs, reg2) stw reg, (offs + 4)(reg2) +#endif + +#define SCRATCH_SAVE \ + /* Enable critical section. We are critical if \ + shared->critical == r1 */ \ + STL64(r1, KVM_MAGIC_PAGE + KVM_MAGIC_CRITICAL, 0); \ + \ + /* Save state */ \ + PPC_STL r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH1)(0); \ + PPC_STL r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH2)(0); \ + mfcr r31; \ + stw r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH3)(0); + +#define SCRATCH_RESTORE \ + /* Restore state */ \ + PPC_LL r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH1)(0); \ + lwz r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH3)(0); \ + mtcr r30; \ + PPC_LL r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH2)(0); \ + \ + /* Disable critical section. We are critical if \ + shared->critical == r1 and r2 is always != r1 */ \ + STL64(r2, KVM_MAGIC_PAGE + KVM_MAGIC_CRITICAL, 0); + +.global kvm_emulate_mtmsrd +kvm_emulate_mtmsrd: + + SCRATCH_SAVE + + /* Put MSR & ~(MSR_EE|MSR_RI) in r31 */ + LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) + lis r30, (~(MSR_EE | MSR_RI))@h + ori r30, r30, (~(MSR_EE | MSR_RI))@l + and r31, r31, r30 + + /* OR the register's (MSR_EE|MSR_RI) on MSR */ +kvm_emulate_mtmsrd_reg: + ori r30, r0, 0 + andi. r30, r30, (MSR_EE|MSR_RI) + or r31, r31, r30 + + /* Put MSR back into magic page */ + STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) + + /* Check if we have to fetch an interrupt */ + lwz r31, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0) + cmpwi r31, 0 + beq+ no_check + + /* Check if we may trigger an interrupt */ + andi. r30, r30, MSR_EE + beq no_check + + SCRATCH_RESTORE + + /* Nag hypervisor */ +kvm_emulate_mtmsrd_orig_ins: + tlbsync + + b kvm_emulate_mtmsrd_branch + +no_check: + + SCRATCH_RESTORE + + /* Go back to caller */ +kvm_emulate_mtmsrd_branch: + b . +kvm_emulate_mtmsrd_end: + +.global kvm_emulate_mtmsrd_branch_offs +kvm_emulate_mtmsrd_branch_offs: + .long (kvm_emulate_mtmsrd_branch - kvm_emulate_mtmsrd) / 4 + +.global kvm_emulate_mtmsrd_reg_offs +kvm_emulate_mtmsrd_reg_offs: + .long (kvm_emulate_mtmsrd_reg - kvm_emulate_mtmsrd) / 4 + +.global kvm_emulate_mtmsrd_orig_ins_offs +kvm_emulate_mtmsrd_orig_ins_offs: + .long (kvm_emulate_mtmsrd_orig_ins - kvm_emulate_mtmsrd) / 4 + +.global kvm_emulate_mtmsrd_len +kvm_emulate_mtmsrd_len: + .long (kvm_emulate_mtmsrd_end - kvm_emulate_mtmsrd) / 4 + + +#define MSR_SAFE_BITS (MSR_EE | MSR_CE | MSR_ME | MSR_RI) +#define MSR_CRITICAL_BITS ~MSR_SAFE_BITS + +.global kvm_emulate_mtmsr +kvm_emulate_mtmsr: + + SCRATCH_SAVE + + /* Fetch old MSR in r31 */ + LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) + + /* Find the changed bits between old and new MSR */ +kvm_emulate_mtmsr_reg1: + ori r30, r0, 0 + xor r31, r30, r31 + + /* Check if we need to really do mtmsr */ + LOAD_REG_IMMEDIATE(r30, MSR_CRITICAL_BITS) + and. r31, r31, r30 + + /* No critical bits changed? Maybe we can stay in the guest. */ + beq maybe_stay_in_guest + +do_mtmsr: + + SCRATCH_RESTORE + + /* Just fire off the mtmsr if it's critical */ +kvm_emulate_mtmsr_orig_ins: + mtmsr r0 + + b kvm_emulate_mtmsr_branch + +maybe_stay_in_guest: + + /* Get the target register in r30 */ +kvm_emulate_mtmsr_reg2: + ori r30, r0, 0 + + /* Check if we have to fetch an interrupt */ + lwz r31, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0) + cmpwi r31, 0 + beq+ no_mtmsr + + /* Check if we may trigger an interrupt */ + andi. r31, r30, MSR_EE + beq no_mtmsr + + b do_mtmsr + +no_mtmsr: + + /* Put MSR into magic page because we don't call mtmsr */ + STL64(r30, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) + + SCRATCH_RESTORE + + /* Go back to caller */ +kvm_emulate_mtmsr_branch: + b . +kvm_emulate_mtmsr_end: + +.global kvm_emulate_mtmsr_branch_offs +kvm_emulate_mtmsr_branch_offs: + .long (kvm_emulate_mtmsr_branch - kvm_emulate_mtmsr) / 4 + +.global kvm_emulate_mtmsr_reg1_offs +kvm_emulate_mtmsr_reg1_offs: + .long (kvm_emulate_mtmsr_reg1 - kvm_emulate_mtmsr) / 4 + +.global kvm_emulate_mtmsr_reg2_offs +kvm_emulate_mtmsr_reg2_offs: + .long (kvm_emulate_mtmsr_reg2 - kvm_emulate_mtmsr) / 4 + +.global kvm_emulate_mtmsr_orig_ins_offs +kvm_emulate_mtmsr_orig_ins_offs: + .long (kvm_emulate_mtmsr_orig_ins - kvm_emulate_mtmsr) / 4 + +.global kvm_emulate_mtmsr_len +kvm_emulate_mtmsr_len: + .long (kvm_emulate_mtmsr_end - kvm_emulate_mtmsr) / 4 + + + +.global kvm_emulate_wrteei +kvm_emulate_wrteei: + + SCRATCH_SAVE + + /* Fetch old MSR in r31 */ + LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) + + /* Remove MSR_EE from old MSR */ + li r30, 0 + ori r30, r30, MSR_EE + andc r31, r31, r30 + + /* OR new MSR_EE onto the old MSR */ +kvm_emulate_wrteei_ee: + ori r31, r31, 0 + + /* Write new MSR value back */ + STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) + + SCRATCH_RESTORE + + /* Go back to caller */ +kvm_emulate_wrteei_branch: + b . +kvm_emulate_wrteei_end: + +.global kvm_emulate_wrteei_branch_offs +kvm_emulate_wrteei_branch_offs: + .long (kvm_emulate_wrteei_branch - kvm_emulate_wrteei) / 4 + +.global kvm_emulate_wrteei_ee_offs +kvm_emulate_wrteei_ee_offs: + .long (kvm_emulate_wrteei_ee - kvm_emulate_wrteei) / 4 + +.global kvm_emulate_wrteei_len +kvm_emulate_wrteei_len: + .long (kvm_emulate_wrteei_end - kvm_emulate_wrteei) / 4 + + +.global kvm_emulate_mtsrin +kvm_emulate_mtsrin: + + SCRATCH_SAVE + + LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0) + andi. r31, r31, MSR_DR | MSR_IR + beq kvm_emulate_mtsrin_reg1 + + SCRATCH_RESTORE + +kvm_emulate_mtsrin_orig_ins: + nop + b kvm_emulate_mtsrin_branch + +kvm_emulate_mtsrin_reg1: + /* rX >> 26 */ + rlwinm r30,r0,6,26,29 + +kvm_emulate_mtsrin_reg2: + stw r0, (KVM_MAGIC_PAGE + KVM_MAGIC_SR)(r30) + + SCRATCH_RESTORE + + /* Go back to caller */ +kvm_emulate_mtsrin_branch: + b . +kvm_emulate_mtsrin_end: + +.global kvm_emulate_mtsrin_branch_offs +kvm_emulate_mtsrin_branch_offs: + .long (kvm_emulate_mtsrin_branch - kvm_emulate_mtsrin) / 4 + +.global kvm_emulate_mtsrin_reg1_offs +kvm_emulate_mtsrin_reg1_offs: + .long (kvm_emulate_mtsrin_reg1 - kvm_emulate_mtsrin) / 4 + +.global kvm_emulate_mtsrin_reg2_offs +kvm_emulate_mtsrin_reg2_offs: + .long (kvm_emulate_mtsrin_reg2 - kvm_emulate_mtsrin) / 4 + +.global kvm_emulate_mtsrin_orig_ins_offs +kvm_emulate_mtsrin_orig_ins_offs: + .long (kvm_emulate_mtsrin_orig_ins - kvm_emulate_mtsrin) / 4 + +.global kvm_emulate_mtsrin_len +kvm_emulate_mtsrin_len: + .long (kvm_emulate_mtsrin_end - kvm_emulate_mtsrin) / 4 |