| Message ID | 20230412094938.2693890-12-luca.fancellu@arm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | SVE feature for arm guests | expand |
Hi Luca, > On 12 Apr 2023, at 11:49, Luca Fancellu <Luca.Fancellu@arm.com> wrote: > > Add a device tree property in the dom0less domU configuration > to enable the guest to use SVE. > > Update documentation. > > Signed-off-by: Luca Fancellu <luca.fancellu@arm.com> Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com> Cheers Bertrand > --- > Changes from v4: > - Now it is possible to specify the property "sve" for dom0less > device tree node without any value, that means the platform > supported VL will be used. > Changes from v3: > - Now domainconfig_encode_vl is named sve_encode_vl > Changes from v2: > - xen_domctl_createdomain field name has changed into sve_vl > and its value is the VL/128, use domainconfig_encode_vl > to encode a plain VL in bits. > Changes from v1: > - No changes > Changes from RFC: > - Changed documentation > --- > docs/misc/arm/device-tree/booting.txt | 11 +++++++++++ > xen/arch/arm/domain_build.c | 24 ++++++++++++++++++++++++ > 2 files changed, 35 insertions(+) > > diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt > index 3879340b5e0a..f9d2ecdda48a 100644 > --- a/docs/misc/arm/device-tree/booting.txt > +++ b/docs/misc/arm/device-tree/booting.txt > @@ -193,6 +193,17 @@ with the following properties: > Optional. Handle to a xen,cpupool device tree node that identifies the > cpupool where the guest will be started at boot. > > +- sve > + > + Optional. A number that, when above 0, enables SVE for this guest and sets > + its maximum SVE vector length. The default value is 0, that means this > + guest is not allowed to use SVE, the maximum value allowed is 2048, any > + other value must be multiple of 128. > + Please note that if the platform supports a lower value of bits, then the > + domain creation will fail. > + Specifying this property with no value, means that the SVE vector length > + will be set equal to the maximum vector length supported by the platform. > + > - xen,enhanced > > A string property. Possible property values are: > diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c > index 3f30ef5c37b6..c1f0d1d78431 100644 > --- a/xen/arch/arm/domain_build.c > +++ b/xen/arch/arm/domain_build.c > @@ -4004,6 +4004,30 @@ void __init create_domUs(void) > d_cfg.max_maptrack_frames = val; > } > > + if ( dt_get_property(node, "sve", &val) ) > + { > + unsigned int sve_vl_bits; > + > + if ( !val ) > + { > + /* Property found with no value, means max HW VL supported */ > + rc = sve_sanitize_vl_param(-1, &sve_vl_bits); > + } > + else > + { > + if ( dt_property_read_u32(node, "sve", &val) ) > + rc = sve_sanitize_vl_param(val, &sve_vl_bits); > + else > + panic("Error reading 'sve' property"); > + } > + > + if ( !rc ) > + d_cfg.arch.sve_vl = sve_encode_vl(sve_vl_bits); > + else > + printk(XENLOG_WARNING > + "SVE vector length error, disable feature for Dom0less DomU\n"); > + } > + > /* > * The variable max_init_domid is initialized with zero, so here it's > * very important to use the pre-increment operator to call > -- > 2.34.1 >
Hi, > On 18 Apr 2023, at 14:55, Bertrand Marquis <Bertrand.Marquis@arm.com> wrote: > > Hi Luca, > >> On 12 Apr 2023, at 11:49, Luca Fancellu <Luca.Fancellu@arm.com> wrote: >> >> Add a device tree property in the dom0less domU configuration >> to enable the guest to use SVE. >> >> Update documentation. >> >> Signed-off-by: Luca Fancellu <luca.fancellu@arm.com> > Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com> In fact the doc needs fixing as the domain creation does not fail. @Luca thanks for mentioning that to me So please fix that and you can keep my R-b (unless some changes are needed after the discussion on parameter handling). Cheers Bertrand > > Cheers > Bertrand > >> --- >> Changes from v4: >> - Now it is possible to specify the property "sve" for dom0less >> device tree node without any value, that means the platform >> supported VL will be used. >> Changes from v3: >> - Now domainconfig_encode_vl is named sve_encode_vl >> Changes from v2: >> - xen_domctl_createdomain field name has changed into sve_vl >> and its value is the VL/128, use domainconfig_encode_vl >> to encode a plain VL in bits. >> Changes from v1: >> - No changes >> Changes from RFC: >> - Changed documentation >> --- >> docs/misc/arm/device-tree/booting.txt | 11 +++++++++++ >> xen/arch/arm/domain_build.c | 24 ++++++++++++++++++++++++ >> 2 files changed, 35 insertions(+) >> >> diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt >> index 3879340b5e0a..f9d2ecdda48a 100644 >> --- a/docs/misc/arm/device-tree/booting.txt >> +++ b/docs/misc/arm/device-tree/booting.txt >> @@ -193,6 +193,17 @@ with the following properties: >> Optional. Handle to a xen,cpupool device tree node that identifies the >> cpupool where the guest will be started at boot. >> >> +- sve >> + >> + Optional. A number that, when above 0, enables SVE for this guest and sets >> + its maximum SVE vector length. The default value is 0, that means this >> + guest is not allowed to use SVE, the maximum value allowed is 2048, any >> + other value must be multiple of 128. >> + Please note that if the platform supports a lower value of bits, then the >> + domain creation will fail. >> + Specifying this property with no value, means that the SVE vector length >> + will be set equal to the maximum vector length supported by the platform. >> + >> - xen,enhanced >> >> A string property. Possible property values are: >> diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c >> index 3f30ef5c37b6..c1f0d1d78431 100644 >> --- a/xen/arch/arm/domain_build.c >> +++ b/xen/arch/arm/domain_build.c >> @@ -4004,6 +4004,30 @@ void __init create_domUs(void) >> d_cfg.max_maptrack_frames = val; >> } >> >> + if ( dt_get_property(node, "sve", &val) ) >> + { >> + unsigned int sve_vl_bits; >> + >> + if ( !val ) >> + { >> + /* Property found with no value, means max HW VL supported */ >> + rc = sve_sanitize_vl_param(-1, &sve_vl_bits); >> + } >> + else >> + { >> + if ( dt_property_read_u32(node, "sve", &val) ) >> + rc = sve_sanitize_vl_param(val, &sve_vl_bits); >> + else >> + panic("Error reading 'sve' property"); >> + } >> + >> + if ( !rc ) >> + d_cfg.arch.sve_vl = sve_encode_vl(sve_vl_bits); >> + else >> + printk(XENLOG_WARNING >> + "SVE vector length error, disable feature for Dom0less DomU\n"); >> + } >> + >> /* >> * The variable max_init_domid is initialized with zero, so here it's >> * very important to use the pre-increment operator to call >> -- >> 2.34.1 >> > >
diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt index 3879340b5e0a..f9d2ecdda48a 100644 --- a/docs/misc/arm/device-tree/booting.txt +++ b/docs/misc/arm/device-tree/booting.txt @@ -193,6 +193,17 @@ with the following properties: Optional. Handle to a xen,cpupool device tree node that identifies the cpupool where the guest will be started at boot. +- sve + + Optional. A number that, when above 0, enables SVE for this guest and sets + its maximum SVE vector length. The default value is 0, that means this + guest is not allowed to use SVE, the maximum value allowed is 2048, any + other value must be multiple of 128. + Please note that if the platform supports a lower value of bits, then the + domain creation will fail. + Specifying this property with no value, means that the SVE vector length + will be set equal to the maximum vector length supported by the platform. + - xen,enhanced A string property. Possible property values are: diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index 3f30ef5c37b6..c1f0d1d78431 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -4004,6 +4004,30 @@ void __init create_domUs(void) d_cfg.max_maptrack_frames = val; } + if ( dt_get_property(node, "sve", &val) ) + { + unsigned int sve_vl_bits; + + if ( !val ) + { + /* Property found with no value, means max HW VL supported */ + rc = sve_sanitize_vl_param(-1, &sve_vl_bits); + } + else + { + if ( dt_property_read_u32(node, "sve", &val) ) + rc = sve_sanitize_vl_param(val, &sve_vl_bits); + else + panic("Error reading 'sve' property"); + } + + if ( !rc ) + d_cfg.arch.sve_vl = sve_encode_vl(sve_vl_bits); + else + printk(XENLOG_WARNING + "SVE vector length error, disable feature for Dom0less DomU\n"); + } + /* * The variable max_init_domid is initialized with zero, so here it's * very important to use the pre-increment operator to call
Add a device tree property in the dom0less domU configuration to enable the guest to use SVE. Update documentation. Signed-off-by: Luca Fancellu <luca.fancellu@arm.com> --- Changes from v4: - Now it is possible to specify the property "sve" for dom0less device tree node without any value, that means the platform supported VL will be used. Changes from v3: - Now domainconfig_encode_vl is named sve_encode_vl Changes from v2: - xen_domctl_createdomain field name has changed into sve_vl and its value is the VL/128, use domainconfig_encode_vl to encode a plain VL in bits. Changes from v1: - No changes Changes from RFC: - Changed documentation --- docs/misc/arm/device-tree/booting.txt | 11 +++++++++++ xen/arch/arm/domain_build.c | 24 ++++++++++++++++++++++++ 2 files changed, 35 insertions(+)