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| author | Dapeng Mi <dapeng1.mi@linux.intel.com> | 2026-09-17 09:52:33 +0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2026-09-22 11:37:46 +0200 |
| commit | 0102c8c7fdfc4bd700971daff2b94470f4eafae4 (patch) | |
| tree | 531306c2299f9a269f0a986e29f17ba972180104 /arch/riscv/kvm/main.c | |
| download | linux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.tar.gz linux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.zip | |
perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rspgrafted
DMR introduces Offmodule Response events in place of the legacy
Offcore Response events, but it still exposes the inherited
offcore_rsp PMU attribute for programming the corresponding MSR data.
Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface
matches the underlying event name and avoids user & tooling confusion.
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com
Diffstat (limited to 'arch/riscv/kvm/main.c')
| -rw-r--r-- | arch/riscv/kvm/main.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c new file mode 100644 index 000000000..89568ccce --- /dev/null +++ b/arch/riscv/kvm/main.c @@ -0,0 +1,271 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/kvm_host.h> +#include <linux/cpu_pm.h> +#include <asm/cpufeature.h> +#include <asm/kvm_mmu.h> +#include <asm/kvm_nacl.h> +#include <asm/sbi.h> +#include <asm/kvm_vcpu_vector.h> + +static DEFINE_PER_CPU(bool, kvm_riscv_virtualization_enabled); + +DEFINE_STATIC_KEY_FALSE(kvm_riscv_vsstage_tlb_no_gpa); + +static void kvm_riscv_setup_vendor_features(void) +{ + /* Andes AX66: split two-stage TLBs */ + if (riscv_cached_mvendorid(0) == ANDES_VENDOR_ID && + (riscv_cached_marchid(0) & 0xFFFF) == 0x8A66) { + static_branch_enable(&kvm_riscv_vsstage_tlb_no_gpa); + kvm_info("VS-stage TLB does not cache guest physical address and VMID\n"); + } +} + +long kvm_arch_dev_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + return -EINVAL; +} + +/* Initialize hypervisor CSRs - called during CPU online and non-retention idle resume */ +static void kvm_riscv_csr_init(void) +{ + csr_write(CSR_HEDELEG, 0); + csr_write(CSR_HIDELEG, 0); + + /* VS should access only the time counter directly. Everything else should trap */ + csr_write(CSR_HCOUNTEREN, 0x02); + + csr_write(CSR_HVIP, 0); +} + +/* Clear hypervisor CSRs - called during CPU offline and non-retention idle entry */ +static void kvm_riscv_csr_cleanup(void) +{ + /* + * After clearing the hideleg CSR, the host kernel will receive + * spurious interrupts if hvip CSR has pending interrupts and the + * corresponding enable bits in vsie CSR are asserted. To avoid it, + * hvip CSR and vsie CSR must be cleared before clearing hideleg CSR. + */ + csr_write(CSR_VSIE, 0); + csr_write(CSR_HVIP, 0); + csr_write(CSR_HEDELEG, 0); + csr_write(CSR_HIDELEG, 0); + + kvm_riscv_clear_former_vcpu(); +} + +int kvm_arch_enable_virtualization_cpu(void) +{ + int rc; + + rc = kvm_riscv_nacl_enable(); + if (rc) + return rc; + + kvm_riscv_csr_init(); + kvm_riscv_aia_enable(); + + __this_cpu_write(kvm_riscv_virtualization_enabled, true); + + return 0; +} + +void kvm_arch_disable_virtualization_cpu(void) +{ + kvm_riscv_aia_disable(); + kvm_riscv_csr_cleanup(); + kvm_riscv_nacl_disable(); + + __this_cpu_write(kvm_riscv_virtualization_enabled, false); +} + +static int kvm_riscv_cpu_pm_notifier(struct notifier_block *self, unsigned long cmd, void *v) +{ + switch (cmd) { + case CPU_PM_EXIT: + case CPU_PM_ENTER_FAILED: + /* + * Only restore hypervisor state if KVM virtualization is + * enabled on this CPU. This prevents unintentional re-enabling + * of virtualization after it has been explicitly disabled. + */ + if (__this_cpu_read(kvm_riscv_virtualization_enabled)) { + kvm_riscv_csr_init(); + kvm_riscv_aia_pm_exit(); + } + return NOTIFY_OK; + case CPU_PM_ENTER: + /* + * Only save and clear hypervisor state if KVM virtualization + * is enabled on this CPU. + */ + if (__this_cpu_read(kvm_riscv_virtualization_enabled)) { + kvm_riscv_aia_pm_enter(); + kvm_riscv_csr_cleanup(); + } + return NOTIFY_OK; + default: + break; + } + + return NOTIFY_DONE; +} + +static struct notifier_block kvm_riscv_cpu_pm_nb = { + .notifier_call = kvm_riscv_cpu_pm_notifier, +}; + +static void kvm_riscv_teardown(void) +{ + kvm_riscv_aia_exit(); + kvm_riscv_nacl_exit(); + kvm_riscv_v_exit(); + kvm_unregister_perf_callbacks(); +} + +static int __init riscv_kvm_init(void) +{ + int rc; + char slist[64]; + const char *str; + + if (!riscv_isa_extension_available(NULL, H)) { + kvm_info("hypervisor extension not available\n"); + return -ENODEV; + } + + if (sbi_spec_is_0_1()) { + kvm_info("require SBI v0.2 or higher\n"); + return -ENODEV; + } + + if (!sbi_probe_extension(SBI_EXT_RFENCE)) { + kvm_info("require SBI RFENCE extension\n"); + return -ENODEV; + } + + rc = kvm_riscv_nacl_init(); + if (rc && rc != -ENODEV) + return rc; + + kvm_riscv_gstage_mode_detect(); + switch (kvm_riscv_gstage_max_pgd_levels) { + case 2: + str = "Sv32x4"; + break; + case 3: + str = "Sv39x4"; + break; + case 4: + str = "Sv48x4"; + break; + case 5: + str = "Sv57x4"; + break; + default: + kvm_riscv_nacl_exit(); + return -ENODEV; + } + + kvm_riscv_gstage_vmid_detect(); + + rc = kvm_riscv_aia_init(); + if (rc && rc != -ENODEV) { + kvm_riscv_nacl_exit(); + return rc; + } + + kvm_info("hypervisor extension available\n"); + + if (kvm_riscv_nacl_available()) { + rc = 0; + slist[0] = '\0'; + if (kvm_riscv_nacl_sync_csr_available()) { + if (rc) + strcat(slist, ", "); + strcat(slist, "sync_csr"); + rc++; + } + if (kvm_riscv_nacl_sync_hfence_available()) { + if (rc) + strcat(slist, ", "); + strcat(slist, "sync_hfence"); + rc++; + } + if (kvm_riscv_nacl_sync_sret_available()) { + if (rc) + strcat(slist, ", "); + strcat(slist, "sync_sret"); + rc++; + } + if (kvm_riscv_nacl_autoswap_csr_available()) { + if (rc) + strcat(slist, ", "); + strcat(slist, "autoswap_csr"); + rc++; + } + kvm_info("using SBI nested acceleration with %s\n", + (rc) ? slist : "no features"); + } + + kvm_info("highest G-stage page table mode is %s\n", str); + + kvm_info("VMID %ld bits available\n", kvm_riscv_gstage_vmid_bits()); + + kvm_riscv_setup_vendor_features(); + + kvm_riscv_v_init(); + + kvm_register_perf_callbacks(); + + /* Register CPU PM notifier for CPU idle non-retention states */ + if (IS_ENABLED(CONFIG_CPU_PM)) { + rc = cpu_pm_register_notifier(&kvm_riscv_cpu_pm_nb); + if (rc) { + kvm_err("Failed to register CPU PM notifier: %d\n", rc); + goto err_teardown; + } + } + + rc = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE); + if (rc) + goto err_unregister_cpu_pm; + + if (kvm_riscv_aia_available()) + kvm_info("AIA available with %d guest external interrupts\n", + atomic_read(&kvm_riscv_aia_nr_hgei)); + + return 0; + +err_unregister_cpu_pm: + if (IS_ENABLED(CONFIG_CPU_PM)) + cpu_pm_unregister_notifier(&kvm_riscv_cpu_pm_nb); +err_teardown: + kvm_riscv_teardown(); + return rc; +} +module_init(riscv_kvm_init); + +static void __exit riscv_kvm_exit(void) +{ + kvm_exit(); + + /* Unregister CPU PM notifier */ + if (IS_ENABLED(CONFIG_CPU_PM)) + cpu_pm_unregister_notifier(&kvm_riscv_cpu_pm_nb); + + kvm_riscv_teardown(); +} +module_exit(riscv_kvm_exit); |
