From patchwork Mon Mar 27 10:59:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Fancellu X-Patchwork-Id: 13189034 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.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 1E0C2C76195 for ; Mon, 27 Mar 2023 11:00:14 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.515172.797838 (Exim 4.92) (envelope-from ) id 1pgka7-000159-22; Mon, 27 Mar 2023 11:00:07 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 515172.797838; Mon, 27 Mar 2023 11:00:07 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pgka6-00014C-P3; Mon, 27 Mar 2023 11:00:06 +0000 Received: by outflank-mailman (input) for mailman id 515172; Mon, 27 Mar 2023 11:00:05 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pgka5-0007YG-LO for xen-devel@lists.xenproject.org; Mon, 27 Mar 2023 11:00:05 +0000 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by se1-gles-sth1.inumbo.com (Halon) with ESMTP id 874313c1-cc8e-11ed-85db-49a42c6b2330; Mon, 27 Mar 2023 13:00:04 +0200 (CEST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7E379C14; Mon, 27 Mar 2023 04:00:48 -0700 (PDT) Received: from e125770.cambridge.arm.com (e125770.arm.com [10.1.195.25]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 025133F663; Mon, 27 Mar 2023 04:00:02 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 874313c1-cc8e-11ed-85db-49a42c6b2330 From: Luca Fancellu To: xen-devel@lists.xenproject.org Cc: bertrand.marquis@arm.com, wei.chen@arm.com, Andrew Cooper , George Dunlap , Jan Beulich , Julien Grall , Stefano Stabellini , Wei Liu , Volodymyr Babchuk Subject: [PATCH v4 07/12] xen: enable Dom0 to use SVE feature Date: Mon, 27 Mar 2023 11:59:39 +0100 Message-Id: <20230327105944.1360856-8-luca.fancellu@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230327105944.1360856-1-luca.fancellu@arm.com> References: <20230327105944.1360856-1-luca.fancellu@arm.com> MIME-Version: 1.0 Add a command line parameter to allow Dom0 the use of SVE resources, the command line parameter sve=, sub argument of dom0=, controls the feature on this domain and sets the maximum SVE vector length for Dom0. Add a new function, parse_integer(), to parse an integer command line argument. Signed-off-by: Luca Fancellu --- Changes from v3: - Don't use fixed len types when not needed (Jan) - renamed domainconfig_encode_vl to sve_encode_vl - Use a sub argument of dom0= to enable the feature (Jan) - Add parse_integer() function Changes from v2: - xen_domctl_createdomain field has changed into sve_vl and its value now is the VL / 128, create an helper function for that. Changes from v1: - No changes Changes from RFC: - Changed docs to explain that the domain won't be created if the requested vector length is above the supported one from the platform. --- docs/misc/xen-command-line.pandoc | 16 ++++++++++++++-- xen/arch/arm/arm64/sve.c | 9 +++++++++ xen/arch/arm/domain_build.c | 11 ++++++++++- xen/arch/arm/include/asm/arm64/sve.h | 16 ++++++++++++++++ xen/common/kernel.c | 24 ++++++++++++++++++++++++ xen/include/xen/lib.h | 10 ++++++++++ 6 files changed, 83 insertions(+), 3 deletions(-) diff --git a/docs/misc/xen-command-line.pandoc b/docs/misc/xen-command-line.pandoc index e0b89b7d3319..06c1eb4e6d6f 100644 --- a/docs/misc/xen-command-line.pandoc +++ b/docs/misc/xen-command-line.pandoc @@ -777,9 +777,9 @@ Specify the bit width of the DMA heap. ### dom0 = List of [ pv | pvh, shadow=, verbose=, - cpuid-faulting=, msr-relaxed= ] + cpuid-faulting=, msr-relaxed= ] (x86) - Applicability: x86 + = List of [ sve= ] (Arm) Controls for how dom0 is constructed on x86 systems. @@ -838,6 +838,18 @@ Controls for how dom0 is constructed on x86 systems. If using this option is necessary to fix an issue, please report a bug. +Enables features on dom0 on Arm systems. + +* The `sve` integer parameter enables Arm SVE usage for Dom0 domain and sets + the maximum SVE vector length. + Values above 0 means feature is enabled for Dom0, otherwise feature is + disabled. + Possible values are from 0 to maximum 2048, being multiple of 128, that will + be the maximum vector length. + Please note that the platform can supports a lower value, if the requested + value is above the supported one, the domain creation will fail and the + system will stop. + ### dom0-cpuid = List of comma separated booleans diff --git a/xen/arch/arm/arm64/sve.c b/xen/arch/arm/arm64/sve.c index 696a97811cac..6416403817e3 100644 --- a/xen/arch/arm/arm64/sve.c +++ b/xen/arch/arm/arm64/sve.c @@ -5,10 +5,14 @@ * Copyright (C) 2022 ARM Ltd. */ +#include #include #include #include +/* opt_dom0_sve: allow Dom0 to use SVE and set maximum vector length. */ +unsigned int __initdata opt_dom0_sve; + extern unsigned int sve_get_hw_vl(void); extern void sve_save_ctx(uint64_t *sve_ctx, uint64_t *pregs, int save_ffr); extern void sve_load_ctx(uint64_t const *sve_ctx, uint64_t const *pregs, @@ -115,3 +119,8 @@ void sve_restore_state(struct vcpu *v) sve_load_ctx(sve_ctx_zreg_end, v->arch.vfp.fpregs, 1); } + +int __init sve_parse_dom0_param(const char *str_begin, const char *str_end) +{ + return parse_integer("sve", str_begin, str_end, (int*)&opt_dom0_sve); +} diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index 35dbe964fc8b..f6019ce30149 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -61,7 +62,12 @@ custom_param("dom0_mem", parse_dom0_mem); int __init parse_arch_dom0_param(const char *str_begin, const char *str_end) { - return -1; + int rc = 0; + + if ( sve_parse_dom0_param(str_begin, str_end) < 0 ) + rc = -EINVAL; + + return rc; } /* Override macros from asm/page.h to make them work with mfn_t */ @@ -4089,6 +4095,9 @@ void __init create_dom0(void) if ( iommu_enabled ) dom0_cfg.flags |= XEN_DOMCTL_CDF_iommu; + if ( opt_dom0_sve > 0 ) + dom0_cfg.arch.sve_vl = sve_encode_vl(opt_dom0_sve); + dom0 = domain_create(0, &dom0_cfg, CDF_privileged | CDF_directmap); if ( IS_ERR(dom0) ) panic("Error creating domain 0 (rc = %ld)\n", PTR_ERR(dom0)); diff --git a/xen/arch/arm/include/asm/arm64/sve.h b/xen/arch/arm/include/asm/arm64/sve.h index d38a37408439..69a1044c37d9 100644 --- a/xen/arch/arm/include/asm/arm64/sve.h +++ b/xen/arch/arm/include/asm/arm64/sve.h @@ -25,8 +25,15 @@ static inline unsigned int sve_decode_vl(unsigned int sve_vl) return sve_vl * SVE_VL_MULTIPLE_VAL; } +static inline unsigned int sve_encode_vl(unsigned int sve_vl_bits) +{ + return sve_vl_bits / SVE_VL_MULTIPLE_VAL; +} + #ifdef CONFIG_ARM64_SVE +extern unsigned int opt_dom0_sve; + register_t compute_max_zcr(void); register_t vl_to_zcr(unsigned int vl); unsigned int get_sys_vl_len(void); @@ -34,9 +41,12 @@ int sve_context_init(struct vcpu *v); void sve_context_free(struct vcpu *v); void sve_save_state(struct vcpu *v); void sve_restore_state(struct vcpu *v); +int sve_parse_dom0_param(const char *str_begin, const char *str_end); #else /* !CONFIG_ARM64_SVE */ +#define opt_dom0_sve (0) + static inline register_t compute_max_zcr(void) { return 0; @@ -61,6 +71,12 @@ static inline void sve_context_free(struct vcpu *v) {} static inline void sve_save_state(struct vcpu *v) {} static inline void sve_restore_state(struct vcpu *v) {} +static inline int sve_parse_dom0_param(const char *str_begin, + const char *str_end) +{ + return -1; +} + #endif #endif /* _ARM_ARM64_SVE_H */ diff --git a/xen/common/kernel.c b/xen/common/kernel.c index f7b1f65f373c..97b460f5a5c2 100644 --- a/xen/common/kernel.c +++ b/xen/common/kernel.c @@ -314,6 +314,30 @@ int parse_boolean(const char *name, const char *s, const char *e) return -1; } +int parse_integer(const char *name, const char *s, const char *e, + int *val) +{ + size_t slen, nlen; + const char *str; + long long pval; + + slen = e ? ({ ASSERT(e >= s); e - s; }) : strlen(s); + nlen = strlen(name); + + /* Does s start with name or contains only the name? */ + if ( (slen <= nlen) || strncmp(s, name, nlen) || (s[nlen] != '=') ) + return -1; + + pval = simple_strtoll(&s[nlen + 1], &str, 0); + + if ( (str != e) || (pval < INT_MIN) || (pval > INT_MAX) ) + return -2; + + *val = pval; + + return 0; +} + int cmdline_strcmp(const char *frag, const char *name) { for ( ; ; frag++, name++ ) diff --git a/xen/include/xen/lib.h b/xen/include/xen/lib.h index 05ee1e18af6b..900f1257acb4 100644 --- a/xen/include/xen/lib.h +++ b/xen/include/xen/lib.h @@ -94,6 +94,16 @@ int parse_bool(const char *s, const char *e); */ int parse_boolean(const char *name, const char *s, const char *e); +/** + * Given a specific name, parses a string of the form: + * $NAME[=...] + * returning 0 and a value in val, for a recognised integer. + * Returns -1 for name not found, general errors, or -2 if name is found but + * not recognised/overflow/underflow value. + */ +int parse_integer(const char *name, const char *s, const char *e, + int *val); + /** * Very similar to strcmp(), but will declare a match if the NUL in 'name' * lines up with comma, colon, semicolon or equals in 'frag'. Designed for