From patchwork Fri May 13 18:17:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Atish Kumar Patra X-Patchwork-Id: 12849253 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2F2CEC433F5 for ; Fri, 13 May 2022 18:42:55 +0000 (UTC) Received: from localhost ([::1]:45496 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1npaFa-0000fW-04 for qemu-devel@archiver.kernel.org; Fri, 13 May 2022 14:42:54 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58812) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1npZrS-00071K-DK for qemu-devel@nongnu.org; Fri, 13 May 2022 14:17:58 -0400 Received: from mail-pj1-x102d.google.com ([2607:f8b0:4864:20::102d]:40621) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1npZrP-0000LV-UY for qemu-devel@nongnu.org; Fri, 13 May 2022 14:17:58 -0400 Received: by mail-pj1-x102d.google.com with SMTP id iq2-20020a17090afb4200b001d93cf33ae9so11494594pjb.5 for ; Fri, 13 May 2022 11:17:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=aLkOPx6j5TUhDcZirqaTlydhJe+iXcoAS/+KSi808t8=; b=h4tBfKpYzHGk7X5MsGxnXqZIXTspWTlCt7d7c/95s3vKK9GD++B8wKEffpAkcMS6Rs Bo3PRJrnat2hU5h9iIqeIpEZtogTTk92P1IF7x8Zjblne1+2LBTaLX6wRFoEcF6bu0La 9fTXrP12Pay2+5wJ+0fl5shWc5alE+x0zFaQ3TRrojNtgFhj64VSSagacWn0V4Uqn/2F bsrwW7nN4cLA3aJ9fMwxfagdG3B4JCbxWASDTXMbWXIyyTPl7VhZtHldmcneEFh1/no4 slYxDZ5wuZH+QwACrBged1has4io349qYyN826GSGG9nk9btMHpLiFcUoDWMqaGD3vNR uMEQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=aLkOPx6j5TUhDcZirqaTlydhJe+iXcoAS/+KSi808t8=; b=uk8VSaL6fdkdtnpCTwAQjiOHpUlGwEwBH8hU4x8VSaE0YxnC//koM3iL27GDCil695 XmFt+dcuWUzDyWPmNfMlqbqQtTFrhoaEQxADitsLVxQ2vq2yRXfR7uf05Lk2o71jEyZv ic5UPzMuaHVX+bGx85bkqKFZbIczufN2oC5TAWT3wVaukeEOUw73ZlmZ+rkmAXM29pdf Rf4FmuKlnrkNfRDtjdxeNOmBJJSziNNeduZRNI8PHU3BMhJ6idsWDPRtj4mi2ZKY8GsB ENn5kQg7AKuEFXUnOw2XLQniOOL7Esp2dABP/DXskUAg+LXDQ+d79odRu0ejdKzrIz/d 6/cw== X-Gm-Message-State: AOAM533AIvOKBuwV3xjdqWJ17XRvCmVqqn6FnXXN3Qf1mqKY+3bMzW8P 4jAriiyYpwZfvBz7HgUM4WRJAL4FEo0BaA== X-Google-Smtp-Source: ABdhPJyU9HC9MMEM+8w5/bcPOylEMwCDdaXoQlie9gm6QtPI2h/RorMDUh30BkPkq+TikNGnW2k4Ig== X-Received: by 2002:a17:90b:304:b0:1d9:752b:437f with SMTP id ay4-20020a17090b030400b001d9752b437fmr17260988pjb.242.1652465874107; Fri, 13 May 2022 11:17:54 -0700 (PDT) Received: from atishp.ba.rivosinc.com ([66.220.2.162]) by smtp.gmail.com with ESMTPSA id gg18-20020a17090b0a1200b001cd4989ff3fsm1907047pjb.6.2022.05.13.11.17.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 13 May 2022 11:17:53 -0700 (PDT) From: Atish Patra To: qemu-devel@nongnu.org Cc: Atish Patra , Alistair Francis , Bin Meng , Palmer Dabbelt , qemu-riscv@nongnu.org Subject: [PATCH v4 2/3] target/riscv: Add stimecmp support Date: Fri, 13 May 2022 11:17:47 -0700 Message-Id: <20220513181748.990645-3-atishp@rivosinc.com> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220513181748.990645-1-atishp@rivosinc.com> References: <20220513181748.990645-1-atishp@rivosinc.com> MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::102d; envelope-from=atishp@rivosinc.com; helo=mail-pj1-x102d.google.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" stimecmp allows the supervisor mode to update stimecmp CSR directly to program the next timer interrupt. This CSR is part of the Sstc extension which was ratified recently. Signed-off-by: Atish Patra --- target/riscv/cpu.c | 8 ++++ target/riscv/cpu.h | 7 +++ target/riscv/cpu_bits.h | 4 ++ target/riscv/csr.c | 92 +++++++++++++++++++++++++++++++++++ target/riscv/machine.c | 2 + target/riscv/meson.build | 3 +- target/riscv/time_helper.c | 98 ++++++++++++++++++++++++++++++++++++++ target/riscv/time_helper.h | 30 ++++++++++++ 8 files changed, 243 insertions(+), 1 deletion(-) create mode 100644 target/riscv/time_helper.c create mode 100644 target/riscv/time_helper.h diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c index 19f4e8294042..d58dd2f857a7 100644 --- a/target/riscv/cpu.c +++ b/target/riscv/cpu.c @@ -23,6 +23,7 @@ #include "qemu/log.h" #include "cpu.h" #include "internals.h" +#include "time_helper.h" #include "exec/exec-all.h" #include "qapi/error.h" #include "qemu/error-report.h" @@ -779,7 +780,12 @@ static void riscv_cpu_init(Object *obj) #ifndef CONFIG_USER_ONLY qdev_init_gpio_in(DEVICE(cpu), riscv_cpu_set_irq, IRQ_LOCAL_MAX + IRQ_LOCAL_GUEST_MAX); + + if (cpu->cfg.ext_sstc) { + riscv_timer_init(cpu); + } #endif /* CONFIG_USER_ONLY */ + } static Property riscv_cpu_properties[] = { @@ -806,6 +812,7 @@ static Property riscv_cpu_properties[] = { DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true), DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true), DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true), + DEFINE_PROP_BOOL("sstc", RISCVCPU, cfg.ext_sstc, true), DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec), DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec), @@ -965,6 +972,7 @@ static void riscv_isa_string_ext(RISCVCPU *cpu, char **isa_str, int max_str_len) ISA_EDATA_ENTRY(zbs, ext_zbs), ISA_EDATA_ENTRY(zve32f, ext_zve32f), ISA_EDATA_ENTRY(zve64f, ext_zve64f), + ISA_EDATA_ENTRY(sstc, ext_sstc), ISA_EDATA_ENTRY(svinval, ext_svinval), ISA_EDATA_ENTRY(svnapot, ext_svnapot), ISA_EDATA_ENTRY(svpbmt, ext_svpbmt), diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index 1119d5201066..9a01e6d0f587 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -276,6 +276,11 @@ struct CPUArchState { uint64_t mfromhost; uint64_t mtohost; + /* Sstc CSRs */ + uint64_t stimecmp; + /* For RV32 only */ + uint8_t stimecmp_wr_done; + /* physical memory protection */ pmp_table_t pmp_state; target_ulong mseccfg; @@ -329,6 +334,7 @@ struct CPUArchState { float_status fp_status; /* Fields from here on are preserved across CPU reset. */ + QEMUTimer *stimer; /* Internal timer for S-mode interrupt */ hwaddr kernel_addr; hwaddr fdt_addr; @@ -379,6 +385,7 @@ struct RISCVCPUConfig { bool ext_counters; bool ext_ifencei; bool ext_icsr; + bool ext_sstc; bool ext_svinval; bool ext_svnapot; bool ext_svpbmt; diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h index 4e5b630f5965..29d0e4a1be01 100644 --- a/target/riscv/cpu_bits.h +++ b/target/riscv/cpu_bits.h @@ -215,6 +215,10 @@ #define CSR_STVAL 0x143 #define CSR_SIP 0x144 +/* Sstc supervisor CSRs */ +#define CSR_STIMECMP 0x14D +#define CSR_STIMECMPH 0x15D + /* Supervisor Protection and Translation */ #define CSR_SPTBR 0x180 #define CSR_SATP 0x180 diff --git a/target/riscv/csr.c b/target/riscv/csr.c index 245f007e66e1..8952d1308008 100644 --- a/target/riscv/csr.c +++ b/target/riscv/csr.c @@ -21,6 +21,7 @@ #include "qemu/log.h" #include "qemu/timer.h" #include "cpu.h" +#include "time_helper.h" #include "qemu/main-loop.h" #include "exec/exec-all.h" #include "sysemu/cpu-timers.h" @@ -537,6 +538,87 @@ static RISCVException read_timeh(CPURISCVState *env, int csrno, return RISCV_EXCP_NONE; } +static RISCVException sstc(CPURISCVState *env, int csrno) +{ + CPUState *cs = env_cpu(env); + RISCVCPU *cpu = RISCV_CPU(cs); + + if (!cpu->cfg.ext_sstc || !env->rdtime_fn) { + return RISCV_EXCP_ILLEGAL_INST; + } + + if (env->priv == PRV_M) { + return RISCV_EXCP_NONE; + } + + if (env->priv != PRV_S) { + return RISCV_EXCP_ILLEGAL_INST; + } + + /* + * No need of separate function for rv32 as menvcfg stores both menvcfg + * menvcfgh for RV32. + */ + if (!(get_field(env->mcounteren, COUNTEREN_TM) && + get_field(env->menvcfg, MENVCFG_STCE))) { + return RISCV_EXCP_ILLEGAL_INST; + } + + return RISCV_EXCP_NONE; +} + +static RISCVException read_stimecmp(CPURISCVState *env, int csrno, + target_ulong *val) +{ + *val = env->stimecmp; + return RISCV_EXCP_NONE; +} + +static RISCVException read_stimecmph(CPURISCVState *env, int csrno, + target_ulong *val) +{ + *val = env->stimecmp >> 32; + return RISCV_EXCP_NONE; +} + +static RISCVException write_stimecmp(CPURISCVState *env, int csrno, + target_ulong val) +{ + RISCVCPU *cpu = env_archcpu(env); + + if (riscv_cpu_mxl(env) == MXL_RV32) { + env->stimecmp = deposit64(env->stimecmp, 0, 32, (uint64_t)val); + env->stimecmp_wr_done |= 0x01; + if (env->stimecmp_wr_done != 0x03) { + return RISCV_EXCP_NONE; + } else { + env->stimecmp_wr_done = 0; + } + } else { + env->stimecmp = val; + } + + riscv_timer_write_timecmp(cpu, env->stimer, env->stimecmp, 0, MIP_STIP); + + return RISCV_EXCP_NONE; +} + +static RISCVException write_stimecmph(CPURISCVState *env, int csrno, + target_ulong val) +{ + RISCVCPU *cpu = env_archcpu(env); + + env->stimecmp = deposit64(env->stimecmp, 32, 32, (uint64_t)val); + env->stimecmp_wr_done |= 0x02; + if (env->stimecmp_wr_done != 0x03) { + return RISCV_EXCP_NONE; + } + env->stimecmp_wr_done = 0; + riscv_timer_write_timecmp(cpu, env->stimer, env->stimecmp, 0, MIP_STIP); + + return RISCV_EXCP_NONE; +} + /* Machine constants */ #define M_MODE_INTERRUPTS ((uint64_t)(MIP_MSIP | MIP_MTIP | MIP_MEIP)) @@ -1515,6 +1597,12 @@ static RISCVException rmw_mip64(CPURISCVState *env, int csrno, new_val |= env->external_seip * MIP_SEIP; } + if (cpu->cfg.ext_sstc && (env->priv == PRV_M) && + get_field(env->menvcfg, MENVCFG_STCE)) { + /* sstc extension forbids STIP & VSTIP to be writeable in mip */ + mask = mask & ~(MIP_STIP | MIP_VSTIP); + } + if (mask) { old_mip = riscv_cpu_update_mip(cpu, mask, (new_val & mask)); } else { @@ -3341,6 +3429,10 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = { [CSR_SCAUSE] = { "scause", smode, read_scause, write_scause }, [CSR_STVAL] = { "stval", smode, read_stval, write_stval }, [CSR_SIP] = { "sip", smode, NULL, NULL, rmw_sip }, + [CSR_STIMECMP] = { "stimecmp", sstc, read_stimecmp, write_stimecmp, + .min_priv_ver = PRIV_VERSION_1_12_0 }, + [CSR_STIMECMPH] = { "stimecmph", sstc, read_stimecmph, write_stimecmph, + .min_priv_ver = PRIV_VERSION_1_12_0 }, /* Supervisor Protection and Translation */ [CSR_SATP] = { "satp", smode, read_satp, write_satp }, diff --git a/target/riscv/machine.c b/target/riscv/machine.c index 7d85de0b1d49..1e775343a37b 100644 --- a/target/riscv/machine.c +++ b/target/riscv/machine.c @@ -334,6 +334,8 @@ const VMStateDescription vmstate_riscv_cpu = { VMSTATE_UINTTL(env.mscratch, RISCVCPU), VMSTATE_UINT64(env.mfromhost, RISCVCPU), VMSTATE_UINT64(env.mtohost, RISCVCPU), + VMSTATE_UINT64(env.stimecmp, RISCVCPU), + VMSTATE_UINT8(env.stimecmp_wr_done, RISCVCPU), VMSTATE_END_OF_LIST() }, diff --git a/target/riscv/meson.build b/target/riscv/meson.build index 2c20f3dd8e9c..1243d019148e 100644 --- a/target/riscv/meson.build +++ b/target/riscv/meson.build @@ -29,7 +29,8 @@ riscv_softmmu_ss.add(files( 'pmp.c', 'debug.c', 'monitor.c', - 'machine.c' + 'machine.c', + 'time_helper.c' )) target_arch += {'riscv': riscv_ss} diff --git a/target/riscv/time_helper.c b/target/riscv/time_helper.c new file mode 100644 index 000000000000..f3fb5eac7b7b --- /dev/null +++ b/target/riscv/time_helper.c @@ -0,0 +1,98 @@ +/* + * RISC-V timer helper implementation. + * + * Copyright (c) 2022 Rivos Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2 or later, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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, see . + */ + +#include "qemu/osdep.h" +#include "qemu/log.h" +#include "cpu_bits.h" +#include "time_helper.h" +#include "hw/intc/riscv_aclint.h" + +static void riscv_stimer_cb(void *opaque) +{ + RISCVCPU *cpu = opaque; + riscv_cpu_update_mip(cpu, MIP_STIP, BOOL_TO_MASK(1)); +} + +/* + * Called when timecmp is written to update the QEMU timer or immediately + * trigger timer interrupt if mtimecmp <= current timer value. + */ +void riscv_timer_write_timecmp(RISCVCPU *cpu, QEMUTimer *timer, + uint64_t timecmp, uint64_t delta, + uint32_t timer_irq) +{ + uint64_t diff, ns_diff, next; + CPURISCVState *env = &cpu->env; + RISCVAclintMTimerState *mtimer = env->rdtime_fn_arg; + uint32_t timebase_freq = mtimer->timebase_freq; + uint64_t rtc_r = env->rdtime_fn(env->rdtime_fn_arg) + delta; + + if (timecmp <= rtc_r) { + /* + * If we're setting an stimecmp value in the "past", + * immediately raise the timer interrupt + */ + riscv_cpu_update_mip(cpu, timer_irq, BOOL_TO_MASK(1)); + return; + } + + /* Clear the [V]STIP bit in mip */ + riscv_cpu_update_mip(cpu, timer_irq, BOOL_TO_MASK(0)); + + /* otherwise, set up the future timer interrupt */ + diff = timecmp - rtc_r; + /* back to ns (note args switched in muldiv64) */ + ns_diff = muldiv64(diff, NANOSECONDS_PER_SECOND, timebase_freq); + + /* + * check if ns_diff overflowed and check if the addition would potentially + * overflow + */ + if ((NANOSECONDS_PER_SECOND > timebase_freq && ns_diff < diff) || + ns_diff > INT64_MAX) { + next = INT64_MAX; + } else { + /* + * as it is very unlikely qemu_clock_get_ns will return a value + * greater than INT64_MAX, no additional check is needed for an + * unsigned integer overflow. + */ + next = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + ns_diff; + /* + * if ns_diff is INT64_MAX next may still be outside the range + * of a signed integer. + */ + next = MIN(next, INT64_MAX); + } + + timer_mod(timer, next); +} + +void riscv_timer_init(RISCVCPU *cpu) +{ + CPURISCVState *env; + + if (!cpu) { + return; + } + + env = &cpu->env; + env->stimer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &riscv_stimer_cb, cpu); + env->stimecmp = 0; + +} diff --git a/target/riscv/time_helper.h b/target/riscv/time_helper.h new file mode 100644 index 000000000000..7b3cdcc35020 --- /dev/null +++ b/target/riscv/time_helper.h @@ -0,0 +1,30 @@ +/* + * RISC-V timer header file. + * + * Copyright (c) 2022 Rivos Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2 or later, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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, see . + */ + +#ifndef RISCV_TIME_HELPER_H +#define RISCV_TIME_HELPER_H + +#include "cpu.h" +#include "qemu/timer.h" + +void riscv_timer_write_timecmp(RISCVCPU *cpu, QEMUTimer *timer, + uint64_t timecmp, uint64_t delta, + uint32_t timer_irq); +void riscv_timer_init(RISCVCPU *cpu); + +#endif