@@ -995,6 +995,19 @@ restrictions set up here. Note that the values to be specified here are
ACPI PXM ones, not Xen internal node numbers. `relaxed` sets up vCPU
affinities to prefer but be not limited to the specified node(s).
+### dom0_sve (arm)
+> `= <integer>`
+
+> Default: `0`
+
+Enable 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_vcpus_pin
> `= <boolean>`
@@ -5,10 +5,15 @@
* Copyright (C) 2022 ARM Ltd.
*/
+#include <xen/param.h>
#include <xen/sched.h>
#include <xen/sizes.h>
#include <asm/arm64/sve.h>
+/* opt_dom0_sve: allow Dom0 to use SVE and set maximum vector length. */
+unsigned int __initdata opt_dom0_sve;
+integer_param("dom0_sve", 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,
@@ -26,6 +26,7 @@
#include <asm/platform.h>
#include <asm/psci.h>
#include <asm/setup.h>
+#include <asm/arm64/sve.h>
#include <asm/cpufeature.h>
#include <asm/domain_build.h>
#include <xen/event.h>
@@ -4076,6 +4077,9 @@ 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_bits = opt_dom0_sve;
+
dom0 = domain_create(0, &dom0_cfg, CDF_privileged | CDF_directmap);
if ( IS_ERR(dom0) || (alloc_dom0_vcpu0(dom0) == NULL) )
panic("Error creating domain 0\n");
@@ -21,6 +21,8 @@ static inline bool is_vl_valid(uint16_t vl)
#ifdef CONFIG_ARM64_SVE
+extern unsigned int opt_dom0_sve;
+
register_t compute_max_zcr(void);
register_t vl_to_zcr(uint16_t vl);
uint16_t get_sys_vl_len(void);
@@ -31,6 +33,8 @@ void sve_restore_state(struct vcpu *v);
#else /* !CONFIG_ARM64_SVE */
+#define opt_dom0_sve (0)
+
static inline register_t compute_max_zcr(void)
{
return 0;
Add a command line parameter to allow Dom0 the use of SVE resources, the command line parameter dom0_sve controls the feature on this domain and sets the maximum SVE vector length for Dom0. Signed-off-by: Luca Fancellu <luca.fancellu@arm.com> --- 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 | 13 +++++++++++++ xen/arch/arm/arm64/sve.c | 5 +++++ xen/arch/arm/domain_build.c | 4 ++++ xen/arch/arm/include/asm/arm64/sve.h | 4 ++++ 4 files changed, 26 insertions(+)