From patchwork Wed Sep 27 03:09:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: zhaotianrui X-Patchwork-Id: 13399876 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B620DCE7A8B for ; Wed, 27 Sep 2023 04:13:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229546AbjI0ENR (ORCPT ); Wed, 27 Sep 2023 00:13:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48054 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229544AbjI0EMO (ORCPT ); Wed, 27 Sep 2023 00:12:14 -0400 Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 50109CD2; Tue, 26 Sep 2023 20:10:14 -0700 (PDT) Received: from loongson.cn (unknown [10.2.5.185]) by gateway (Coremail) with SMTP id _____8BxIvAPnRNlcRctAA--.20170S3; Wed, 27 Sep 2023 11:10:07 +0800 (CST) Received: from localhost.localdomain (unknown [10.2.5.185]) by localhost.localdomain (Coremail) with SMTP id AQAAf8Cxjd4InRNlhZETAA--.42466S20; Wed, 27 Sep 2023 11:10:07 +0800 (CST) From: Tianrui Zhao To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini , Huacai Chen , WANG Xuerui , Greg Kroah-Hartman , loongarch@lists.linux.dev, Jens Axboe , Mark Brown , Alex Deucher , Oliver Upton , maobibo@loongson.cn, Xi Ruoyao , zhaotianrui@loongson.cn, Huacai Chen Subject: [PATCH v22 18/25] LoongArch: KVM: Implement handle gspr exception Date: Wed, 27 Sep 2023 11:09:52 +0800 Message-Id: <20230927030959.3629941-19-zhaotianrui@loongson.cn> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230927030959.3629941-1-zhaotianrui@loongson.cn> References: <20230927030959.3629941-1-zhaotianrui@loongson.cn> MIME-Version: 1.0 X-CM-TRANSID: AQAAf8Cxjd4InRNlhZETAA--.42466S20 X-CM-SenderInfo: p2kd03xldq233l6o00pqjv00gofq/ X-Coremail-Antispam: 1Uk129KBjDUn29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7KY7 ZEXasCq-sGcSsGvfJ3UbIjqfuFe4nvWSU5nxnvy29KBjDU0xBIdaVrnUUvcSsGvfC2Kfnx nUUI43ZEXa7xR_UUUUUUUUU== Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Implement kvm handle gspr exception interface, including emulate the reading and writing of cpucfg, csr, iocsr resource. Reviewed-by: Bibo Mao Tested-by: Huacai Chen Signed-off-by: Tianrui Zhao --- arch/loongarch/kvm/exit.c | 107 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 107 insertions(+) diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c index d4d7e74f72..33d1b4190a 100644 --- a/arch/loongarch/kvm/exit.c +++ b/arch/loongarch/kvm/exit.c @@ -214,3 +214,110 @@ int kvm_emu_idle(struct kvm_vcpu *vcpu) return EMULATE_DONE; } + +static int kvm_trap_handle_gspr(struct kvm_vcpu *vcpu) +{ + int rd, rj; + unsigned int index; + unsigned long curr_pc; + larch_inst inst; + enum emulation_result er = EMULATE_DONE; + struct kvm_run *run = vcpu->run; + + /* Fetch the instruction */ + inst.word = vcpu->arch.badi; + curr_pc = vcpu->arch.pc; + update_pc(&vcpu->arch); + + trace_kvm_exit_gspr(vcpu, inst.word); + er = EMULATE_FAIL; + switch (((inst.word >> 24) & 0xff)) { + case 0x0: /* CPUCFG GSPR */ + if (inst.reg2_format.opcode == 0x1B) { + rd = inst.reg2_format.rd; + rj = inst.reg2_format.rj; + ++vcpu->stat.cpucfg_exits; + index = vcpu->arch.gprs[rj]; + er = EMULATE_DONE; + /* + * By LoongArch Reference Manual 2.2.10.5 + * return value is 0 for undefined cpucfg index + */ + if (index < KVM_MAX_CPUCFG_REGS) + vcpu->arch.gprs[rd] = vcpu->arch.cpucfg[index]; + else + vcpu->arch.gprs[rd] = 0; + } + break; + case 0x4: /* CSR{RD,WR,XCHG} GSPR */ + er = kvm_handle_csr(vcpu, inst); + break; + case 0x6: /* Cache, Idle and IOCSR GSPR */ + switch (((inst.word >> 22) & 0x3ff)) { + case 0x18: /* Cache GSPR */ + er = EMULATE_DONE; + trace_kvm_exit_cache(vcpu, KVM_TRACE_EXIT_CACHE); + break; + case 0x19: /* Idle/IOCSR GSPR */ + switch (((inst.word >> 15) & 0x1ffff)) { + case 0xc90: /* IOCSR GSPR */ + er = kvm_emu_iocsr(inst, run, vcpu); + break; + case 0xc91: /* Idle GSPR */ + er = kvm_emu_idle(vcpu); + break; + default: + er = EMULATE_FAIL; + break; + } + break; + default: + er = EMULATE_FAIL; + break; + } + break; + default: + er = EMULATE_FAIL; + break; + } + + /* Rollback PC only if emulation was unsuccessful */ + if (er == EMULATE_FAIL) { + kvm_err("[%#lx]%s: unsupported gspr instruction 0x%08x\n", + curr_pc, __func__, inst.word); + + kvm_arch_vcpu_dump_regs(vcpu); + vcpu->arch.pc = curr_pc; + } + + return er; +} + +/* + * Trigger GSPR: + * 1) Execute CPUCFG instruction; + * 2) Execute CACOP/IDLE instructions; + * 3) Access to unimplemented CSRs/IOCSRs. + */ +static int kvm_handle_gspr(struct kvm_vcpu *vcpu) +{ + int ret = RESUME_GUEST; + enum emulation_result er = EMULATE_DONE; + + er = kvm_trap_handle_gspr(vcpu); + + if (er == EMULATE_DONE) { + ret = RESUME_GUEST; + } else if (er == EMULATE_DO_MMIO) { + vcpu->run->exit_reason = KVM_EXIT_MMIO; + ret = RESUME_HOST; + } else if (er == EMULATE_DO_IOCSR) { + vcpu->run->exit_reason = KVM_EXIT_LOONGARCH_IOCSR; + ret = RESUME_HOST; + } else { + kvm_queue_exception(vcpu, EXCCODE_INE, 0); + ret = RESUME_GUEST; + } + + return ret; +}