From be26db61e880b3892f189e9ef54b7b80599245bf Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Mon, 22 Apr 2024 20:01:55 +0000 Subject: [PATCH] KVM: selftests: Add a minimal library for interacting with an ITS A prerequisite of testing LPI injection performance is of course instantiating an ITS for the guest. Add a small library for creating an ITS and interacting with it from the guest. Signed-off-by: Oliver Upton Link: https://lore.kernel.org/r/20240422200158.2606761-17-oliver.upton@linux.dev Signed-off-by: Marc Zyngier --- tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/aarch64/gic.h | 8 +- .../kvm/include/aarch64/gic_v3_its.h | 19 ++ .../selftests/kvm/include/aarch64/vgic.h | 2 + .../selftests/kvm/lib/aarch64/gic_v3_its.c | 248 ++++++++++++++++++ .../testing/selftests/kvm/lib/aarch64/vgic.c | 18 ++ 6 files changed, 295 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/kvm/include/aarch64/gic_v3_its.h create mode 100644 tools/testing/selftests/kvm/lib/aarch64/gic_v3_its.c diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 741c7dc16afc75..4335e5744cc6d8 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -45,6 +45,7 @@ LIBKVM_x86_64 += lib/x86_64/vmx.c LIBKVM_aarch64 += lib/aarch64/gic.c LIBKVM_aarch64 += lib/aarch64/gic_v3.c +LIBKVM_aarch64 += lib/aarch64/gic_v3_its.c LIBKVM_aarch64 += lib/aarch64/handlers.S LIBKVM_aarch64 += lib/aarch64/processor.c LIBKVM_aarch64 += lib/aarch64/spinlock.c diff --git a/tools/testing/selftests/kvm/include/aarch64/gic.h b/tools/testing/selftests/kvm/include/aarch64/gic.h index 53617b3f52cf5a..6d03188435e437 100644 --- a/tools/testing/selftests/kvm/include/aarch64/gic.h +++ b/tools/testing/selftests/kvm/include/aarch64/gic.h @@ -13,10 +13,16 @@ enum gic_type { GIC_TYPE_MAX, }; -#define GICD_BASE_GPA 0x8000000ULL +/* + * Note that the redistributor frames are at the end, as the range scales + * with the number of vCPUs in the VM. + */ +#define GITS_BASE_GPA 0x8000000ULL +#define GICD_BASE_GPA (GITS_BASE_GPA + KVM_VGIC_V3_ITS_SIZE) #define GICR_BASE_GPA (GICD_BASE_GPA + KVM_VGIC_V3_DIST_SIZE) /* The GIC is identity-mapped into the guest at the time of setup. */ +#define GITS_BASE_GVA ((volatile void *)GITS_BASE_GPA) #define GICD_BASE_GVA ((volatile void *)GICD_BASE_GPA) #define GICR_BASE_GVA ((volatile void *)GICR_BASE_GPA) diff --git a/tools/testing/selftests/kvm/include/aarch64/gic_v3_its.h b/tools/testing/selftests/kvm/include/aarch64/gic_v3_its.h new file mode 100644 index 00000000000000..3722ed9c8f96ed --- /dev/null +++ b/tools/testing/selftests/kvm/include/aarch64/gic_v3_its.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __SELFTESTS_GIC_V3_ITS_H__ +#define __SELFTESTS_GIC_V3_ITS_H__ + +#include + +void its_init(vm_paddr_t coll_tbl, size_t coll_tbl_sz, + vm_paddr_t device_tbl, size_t device_tbl_sz, + vm_paddr_t cmdq, size_t cmdq_size); + +void its_send_mapd_cmd(void *cmdq_base, u32 device_id, vm_paddr_t itt_base, + size_t itt_size, bool valid); +void its_send_mapc_cmd(void *cmdq_base, u32 vcpu_id, u32 collection_id, bool valid); +void its_send_mapti_cmd(void *cmdq_base, u32 device_id, u32 event_id, + u32 collection_id, u32 intid); +void its_send_invall_cmd(void *cmdq_base, u32 collection_id); + +#endif // __SELFTESTS_GIC_V3_ITS_H__ diff --git a/tools/testing/selftests/kvm/include/aarch64/vgic.h b/tools/testing/selftests/kvm/include/aarch64/vgic.h index ce19aa0a8360f0..c481d0c00a5d22 100644 --- a/tools/testing/selftests/kvm/include/aarch64/vgic.h +++ b/tools/testing/selftests/kvm/include/aarch64/vgic.h @@ -32,4 +32,6 @@ void kvm_irq_write_isactiver(int gic_fd, uint32_t intid, struct kvm_vcpu *vcpu); #define KVM_IRQCHIP_NUM_PINS (1020 - 32) +int vgic_its_setup(struct kvm_vm *vm); + #endif // SELFTEST_KVM_VGIC_H diff --git a/tools/testing/selftests/kvm/lib/aarch64/gic_v3_its.c b/tools/testing/selftests/kvm/lib/aarch64/gic_v3_its.c new file mode 100644 index 00000000000000..09f27054564693 --- /dev/null +++ b/tools/testing/selftests/kvm/lib/aarch64/gic_v3_its.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Guest ITS library, generously donated by drivers/irqchip/irq-gic-v3-its.c + * over in the kernel tree. + */ + +#include +#include +#include +#include + +#include "kvm_util.h" +#include "vgic.h" +#include "gic.h" +#include "gic_v3.h" +#include "processor.h" + +static u64 its_read_u64(unsigned long offset) +{ + return readq_relaxed(GITS_BASE_GVA + offset); +} + +static void its_write_u64(unsigned long offset, u64 val) +{ + writeq_relaxed(val, GITS_BASE_GVA + offset); +} + +static u32 its_read_u32(unsigned long offset) +{ + return readl_relaxed(GITS_BASE_GVA + offset); +} + +static void its_write_u32(unsigned long offset, u32 val) +{ + writel_relaxed(val, GITS_BASE_GVA + offset); +} + +static unsigned long its_find_baser(unsigned int type) +{ + int i; + + for (i = 0; i < GITS_BASER_NR_REGS; i++) { + u64 baser; + unsigned long offset = GITS_BASER + (i * sizeof(baser)); + + baser = its_read_u64(offset); + if (GITS_BASER_TYPE(baser) == type) + return offset; + } + + GUEST_FAIL("Couldn't find an ITS BASER of type %u", type); + return -1; +} + +static void its_install_table(unsigned int type, vm_paddr_t base, size_t size) +{ + unsigned long offset = its_find_baser(type); + u64 baser; + + baser = ((size / SZ_64K) - 1) | + GITS_BASER_PAGE_SIZE_64K | + GITS_BASER_InnerShareable | + base | + GITS_BASER_RaWaWb | + GITS_BASER_VALID; + + its_write_u64(offset, baser); +} + +static void its_install_cmdq(vm_paddr_t base, size_t size) +{ + u64 cbaser; + + cbaser = ((size / SZ_4K) - 1) | + GITS_CBASER_InnerShareable | + base | + GITS_CBASER_RaWaWb | + GITS_CBASER_VALID; + + its_write_u64(GITS_CBASER, cbaser); +} + +void its_init(vm_paddr_t coll_tbl, size_t coll_tbl_sz, + vm_paddr_t device_tbl, size_t device_tbl_sz, + vm_paddr_t cmdq, size_t cmdq_size) +{ + u32 ctlr; + + its_install_table(GITS_BASER_TYPE_COLLECTION, coll_tbl, coll_tbl_sz); + its_install_table(GITS_BASER_TYPE_DEVICE, device_tbl, device_tbl_sz); + its_install_cmdq(cmdq, cmdq_size); + + ctlr = its_read_u32(GITS_CTLR); + ctlr |= GITS_CTLR_ENABLE; + its_write_u32(GITS_CTLR, ctlr); +} + +struct its_cmd_block { + union { + u64 raw_cmd[4]; + __le64 raw_cmd_le[4]; + }; +}; + +static inline void its_fixup_cmd(struct its_cmd_block *cmd) +{ + /* Let's fixup BE commands */ + cmd->raw_cmd_le[0] = cpu_to_le64(cmd->raw_cmd[0]); + cmd->raw_cmd_le[1] = cpu_to_le64(cmd->raw_cmd[1]); + cmd->raw_cmd_le[2] = cpu_to_le64(cmd->raw_cmd[2]); + cmd->raw_cmd_le[3] = cpu_to_le64(cmd->raw_cmd[3]); +} + +static void its_mask_encode(u64 *raw_cmd, u64 val, int h, int l) +{ + u64 mask = GENMASK_ULL(h, l); + *raw_cmd &= ~mask; + *raw_cmd |= (val << l) & mask; +} + +static void its_encode_cmd(struct its_cmd_block *cmd, u8 cmd_nr) +{ + its_mask_encode(&cmd->raw_cmd[0], cmd_nr, 7, 0); +} + +static void its_encode_devid(struct its_cmd_block *cmd, u32 devid) +{ + its_mask_encode(&cmd->raw_cmd[0], devid, 63, 32); +} + +static void its_encode_event_id(struct its_cmd_block *cmd, u32 id) +{ + its_mask_encode(&cmd->raw_cmd[1], id, 31, 0); +} + +static void its_encode_phys_id(struct its_cmd_block *cmd, u32 phys_id) +{ + its_mask_encode(&cmd->raw_cmd[1], phys_id, 63, 32); +} + +static void its_encode_size(struct its_cmd_block *cmd, u8 size) +{ + its_mask_encode(&cmd->raw_cmd[1], size, 4, 0); +} + +static void its_encode_itt(struct its_cmd_block *cmd, u64 itt_addr) +{ + its_mask_encode(&cmd->raw_cmd[2], itt_addr >> 8, 51, 8); +} + +static void its_encode_valid(struct its_cmd_block *cmd, int valid) +{ + its_mask_encode(&cmd->raw_cmd[2], !!valid, 63, 63); +} + +static void its_encode_target(struct its_cmd_block *cmd, u64 target_addr) +{ + its_mask_encode(&cmd->raw_cmd[2], target_addr >> 16, 51, 16); +} + +static void its_encode_collection(struct its_cmd_block *cmd, u16 col) +{ + its_mask_encode(&cmd->raw_cmd[2], col, 15, 0); +} + +#define GITS_CMDQ_POLL_ITERATIONS 0 + +static void its_send_cmd(void *cmdq_base, struct its_cmd_block *cmd) +{ + u64 cwriter = its_read_u64(GITS_CWRITER); + struct its_cmd_block *dst = cmdq_base + cwriter; + u64 cbaser = its_read_u64(GITS_CBASER); + size_t cmdq_size; + u64 next; + int i; + + cmdq_size = ((cbaser & 0xFF) + 1) * SZ_4K; + + its_fixup_cmd(cmd); + + WRITE_ONCE(*dst, *cmd); + dsb(ishst); + next = (cwriter + sizeof(*cmd)) % cmdq_size; + its_write_u64(GITS_CWRITER, next); + + /* + * Polling isn't necessary considering KVM's ITS emulation at the time + * of writing this, as the CMDQ is processed synchronously after a write + * to CWRITER. + */ + for (i = 0; its_read_u64(GITS_CREADR) != next; i++) { + __GUEST_ASSERT(i < GITS_CMDQ_POLL_ITERATIONS, + "ITS didn't process command at offset %lu after %d iterations\n", + cwriter, i); + + cpu_relax(); + } +} + +void its_send_mapd_cmd(void *cmdq_base, u32 device_id, vm_paddr_t itt_base, + size_t itt_size, bool valid) +{ + struct its_cmd_block cmd = {}; + + its_encode_cmd(&cmd, GITS_CMD_MAPD); + its_encode_devid(&cmd, device_id); + its_encode_size(&cmd, ilog2(itt_size) - 1); + its_encode_itt(&cmd, itt_base); + its_encode_valid(&cmd, valid); + + its_send_cmd(cmdq_base, &cmd); +} + +void its_send_mapc_cmd(void *cmdq_base, u32 vcpu_id, u32 collection_id, bool valid) +{ + struct its_cmd_block cmd = {}; + + its_encode_cmd(&cmd, GITS_CMD_MAPC); + its_encode_collection(&cmd, collection_id); + its_encode_target(&cmd, vcpu_id); + its_encode_valid(&cmd, valid); + + its_send_cmd(cmdq_base, &cmd); +} + +void its_send_mapti_cmd(void *cmdq_base, u32 device_id, u32 event_id, + u32 collection_id, u32 intid) +{ + struct its_cmd_block cmd = {}; + + its_encode_cmd(&cmd, GITS_CMD_MAPTI); + its_encode_devid(&cmd, device_id); + its_encode_event_id(&cmd, event_id); + its_encode_phys_id(&cmd, intid); + its_encode_collection(&cmd, collection_id); + + its_send_cmd(cmdq_base, &cmd); +} + +void its_send_invall_cmd(void *cmdq_base, u32 collection_id) +{ + struct its_cmd_block cmd = {}; + + its_encode_cmd(&cmd, GITS_CMD_INVALL); + its_encode_collection(&cmd, collection_id); + + its_send_cmd(cmdq_base, &cmd); +} diff --git a/tools/testing/selftests/kvm/lib/aarch64/vgic.c b/tools/testing/selftests/kvm/lib/aarch64/vgic.c index 7738fdb0cea170..5e8f0d5382c27f 100644 --- a/tools/testing/selftests/kvm/lib/aarch64/vgic.c +++ b/tools/testing/selftests/kvm/lib/aarch64/vgic.c @@ -166,3 +166,21 @@ void kvm_irq_write_isactiver(int gic_fd, uint32_t intid, struct kvm_vcpu *vcpu) { vgic_poke_irq(gic_fd, intid, vcpu, GICD_ISACTIVER); } + +int vgic_its_setup(struct kvm_vm *vm) +{ + int its_fd = kvm_create_device(vm, KVM_DEV_TYPE_ARM_VGIC_ITS); + u64 attr; + + attr = GITS_BASE_GPA; + kvm_device_attr_set(its_fd, KVM_DEV_ARM_VGIC_GRP_ADDR, + KVM_VGIC_ITS_ADDR_TYPE, &attr); + + kvm_device_attr_set(its_fd, KVM_DEV_ARM_VGIC_GRP_CTRL, + KVM_DEV_ARM_VGIC_CTRL_INIT, NULL); + + virt_map(vm, GITS_BASE_GPA, GITS_BASE_GPA, + vm_calc_num_guest_pages(vm->mode, KVM_VGIC_V3_ITS_SIZE)); + + return its_fd; +}