[PATCH v2 05/11] virt: gunyah: Add sysfs nodes
From: Elliot Berman
Date: Thu Jul 14 2022 - 17:30:29 EST
Add /sys/hypervisor support when detecting that Linux is running in a
Gunyah environment. Export the version of Gunyah which is reported via
the hyp_identify hypercall.
Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>
---
.../ABI/testing/sysfs-hypervisor-gunyah | 37 +++++
MAINTAINERS | 2 +
arch/arm64/include/asm/gunyah.h | 4 +
drivers/virt/Kconfig | 1 +
drivers/virt/Makefile | 1 +
drivers/virt/gunyah/Kconfig | 13 ++
drivers/virt/gunyah/Makefile | 4 +
drivers/virt/gunyah/sysfs.c | 139 ++++++++++++++++++
8 files changed, 201 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-hypervisor-gunyah
create mode 100644 drivers/virt/gunyah/Kconfig
create mode 100644 drivers/virt/gunyah/Makefile
create mode 100644 drivers/virt/gunyah/sysfs.c
diff --git a/Documentation/ABI/testing/sysfs-hypervisor-gunyah b/Documentation/ABI/testing/sysfs-hypervisor-gunyah
new file mode 100644
index 000000000000..ebbdd0aead7b
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-hypervisor-gunyah
@@ -0,0 +1,37 @@
+What: /sys/hypervisor/type
+Date: January 2022
+KernelVersion: 5.17
+Contact: linux-arm-msm@xxxxxxxxxxxxxxx
+Description: If running under Gunyah:
+ Type of hypervisor:
+ "gunyah": Gunyah hypervisor
+
+What: /sys/hypervisor/features
+Date: January 2022
+KernelVersion: 5.17
+Contact: linux-arm-msm@xxxxxxxxxxxxxxx
+Description: If running under Gunyah:
+ Space separated list of features supported by Linux and Gunyah:
+ "cspace": Gunyah devices
+ "doorbell": Sending/receiving virtual interrupts via Gunyah doorbells
+ "message-queue": Sending/receiving messages via Gunyah message queues
+ "vic": Interrupt lending
+ "vpm": Virtual platform management
+ "vcpu": Virtual CPU management
+ "memextent": Memory lending/management
+ "trace": Gunyah hypervisor tracing
+
+
+What: /sys/hypervisor/version/api
+Date: April 2020
+KernelVersion: 5.17
+Contact: linux-arm-msm@xxxxxxxxxxxxxxx
+Description: If running under Gunyah:
+ The Gunyah API version.
+
+What: /sys/hypervisor/version/variant
+Date: April 2020
+KernelVersion: 5.17
+Contact: linux-arm-msm@xxxxxxxxxxxxxxx
+Description: If running under Gunyah:
+ The Gunyah variant (build) version.
\ No newline at end of file
diff --git a/MAINTAINERS b/MAINTAINERS
index 405a13e1f4d7..5d46c1f91b92 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8740,9 +8740,11 @@ M: Elliot Berman <quic_eberman@xxxxxxxxxxx>
M: Murali Nalajala <quic_mnalajal@xxxxxxxxxxx>
L: linux-arm-msm@xxxxxxxxxxxxxxx
S: Maintained
+F: Documentation/ABI/testing/sysfs-hypervisor-gunyah
F: Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml
F: Documentation/virt/gunyah/
F: arch/arm64/include/asm/gunyah.h
+F: drivers/virt/gunyah/
F: include/linux/gunyah.h
HABANALABS PCI DRIVER
diff --git a/arch/arm64/include/asm/gunyah.h b/arch/arm64/include/asm/gunyah.h
index 2dbef08d58d7..3eef2a9ea299 100644
--- a/arch/arm64/include/asm/gunyah.h
+++ b/arch/arm64/include/asm/gunyah.h
@@ -19,11 +19,15 @@
(GH_CALL_TYPE_SERVICE << GH_CALL_TYPE_SHIFT) \
| ((fn) & GH_CALL_FUNCTION_NUM_MASK))
+#define GH_HYPERCALL_CALL_UID GH_SERVICE(0x3f01)
+
#define GH_HYPERCALL(fn) ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_64, \
ARM_SMCCC_OWNER_VENDOR_HYP, \
(GH_CALL_TYPE_HYPERCALL << GH_CALL_TYPE_SHIFT) \
| ((fn) & GH_CALL_FUNCTION_NUM_MASK))
+#define GH_HYPERCALL_HYP_IDENTIFY GH_HYPERCALL(0x0000)
+
#define ___gh_count_args(_0, _1, _2, _3, _4, _5, _6, _7, _8, x, ...) x
#define __gh_count_args(...) \
diff --git a/drivers/virt/Kconfig b/drivers/virt/Kconfig
index 87ef258cec64..259dc2be6cad 100644
--- a/drivers/virt/Kconfig
+++ b/drivers/virt/Kconfig
@@ -52,4 +52,5 @@ source "drivers/virt/coco/efi_secret/Kconfig"
source "drivers/virt/coco/sev-guest/Kconfig"
+source "drivers/virt/gunyah/Kconfig"
endif
diff --git a/drivers/virt/Makefile b/drivers/virt/Makefile
index 093674e05c40..ec4fdfa8eef1 100644
--- a/drivers/virt/Makefile
+++ b/drivers/virt/Makefile
@@ -6,6 +6,7 @@
obj-$(CONFIG_FSL_HV_MANAGER) += fsl_hypervisor.o
obj-$(CONFIG_VMGENID) += vmgenid.o
obj-y += vboxguest/
+obj-$(CONFIG_GUNYAH) += gunyah/
obj-$(CONFIG_NITRO_ENCLAVES) += nitro_enclaves/
obj-$(CONFIG_ACRN_HSM) += acrn/
diff --git a/drivers/virt/gunyah/Kconfig b/drivers/virt/gunyah/Kconfig
new file mode 100644
index 000000000000..e88289963518
--- /dev/null
+++ b/drivers/virt/gunyah/Kconfig
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config GUNYAH
+ tristate "Gunyah Virtualization drivers"
+ depends on ARM64
+ select SYS_HYPERVISOR
+ help
+ The Gunyah drivers are the helper interfaces that runs in a guest VM
+ such as basic inter-VM IPC and signaling mechanism,s and higher level
+ services such as memory/device sharing, IRQ sharing, and so on.
+
+ Say Y here to enable the drivers needed to interact in a Gunyah
+ virtual environment.
diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile
new file mode 100644
index 000000000000..0aa086f9149f
--- /dev/null
+++ b/drivers/virt/gunyah/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+gunyah-y += sysfs.o
+obj-$(CONFIG_GUNYAH) += gunyah.o
\ No newline at end of file
diff --git a/drivers/virt/gunyah/sysfs.c b/drivers/virt/gunyah/sysfs.c
new file mode 100644
index 000000000000..253433a939cf
--- /dev/null
+++ b/drivers/virt/gunyah/sysfs.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#define pr_fmt(fmt) "gunyah: " fmt
+
+#include <linux/kobject.h>
+#include <linux/gunyah.h>
+#include <linux/module.h>
+#include <linux/printk.h>
+#include <linux/init.h>
+#include <linux/of.h>
+
+#define QC_HYP_UID0 0x19bd54bd
+#define QC_HYP_UID1 0x0b37571b
+#define QC_HYP_UID2 0x946f609b
+#define QC_HYP_UID3 0x54539de6
+
+#define GUNYAH_UID0 0x673d5f14
+#define GUNYAH_UID1 0x9265ce36
+#define GUNYAH_UID2 0xa4535fdb
+#define GUNYAH_UID3 0xc1d58fcd
+
+#define gh_uid_matches(prefix, uid) \
+ ((uid)[0] == prefix ## _UID0 && (uid)[1] == prefix ## _UID1 && \
+ (uid)[2] == prefix ## _UID2 && (uid)[3] == prefix ## _UID3)
+
+#define GH_API_INFO_API_VERSION(x) (((x) >> 0) & 0x3fff)
+#define GH_API_INFO_BIG_ENDIAN(x) (((x) >> 14) & 1)
+#define GH_API_INFO_IS_64BIT(x) (((x) >> 15) & 1)
+#define GH_API_INFO_VARIANT(x) (((x) >> 56) & 0xff)
+
+#define GH_IDENTIFY_PARTITION_CSPACE(flags) (((flags)[0] >> 0) & 1)
+#define GH_IDENTIFY_DOORBELL(flags) (((flags)[0] >> 1) & 1)
+#define GH_IDENTIFY_MSGQUEUE(flags) (((flags)[0] >> 2) & 1)
+#define GH_IDENTIFY_VIC(flags) (((flags)[0] >> 3) & 1)
+#define GH_IDENTIFY_VPM(flags) (((flags)[0] >> 4) & 1)
+#define GH_IDENTIFY_VCPU(flags) (((flags)[0] >> 5) & 1)
+#define GH_IDENTIFY_MEMEXTENT(flags) (((flags)[0] >> 6) & 1)
+#define GH_IDENTIFY_TRACE_CTRL(flags) (((flags)[0] >> 7) & 1)
+
+struct gh_hypercall_hyp_identify_resp {
+ u64 api_info;
+ u64 flags[3];
+};
+
+static struct gh_hypercall_hyp_identify_resp gunyah_api;
+
+static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, char *buffer)
+{
+ return sysfs_emit(buffer, "gunyah\n");
+}
+static struct kobj_attribute type_attr = __ATTR_RO(type);
+
+static ssize_t api_show(struct kobject *kobj, struct kobj_attribute *attr, char *buffer)
+{
+ return sysfs_emit(buffer, "%d\n", (int)GH_API_INFO_API_VERSION(gunyah_api.api_info));
+}
+static struct kobj_attribute api_attr = __ATTR_RO(api);
+
+static ssize_t variant_show(struct kobject *kobj, struct kobj_attribute *attr, char *buffer)
+{
+ return sysfs_emit(buffer, "%d\n", (int)GH_API_INFO_VARIANT(gunyah_api.api_info));
+}
+static struct kobj_attribute variant_attr = __ATTR_RO(variant);
+
+static ssize_t features_show(struct kobject *kobj, struct kobj_attribute *attr, char *buffer)
+{
+ return sysfs_emit(buffer, "\n");
+}
+static struct kobj_attribute features_attr = __ATTR_RO(features);
+
+static struct attribute *version_attrs[] = {
+ &api_attr.attr,
+ &variant_attr.attr,
+ NULL
+};
+
+static const struct attribute_group version_group = {
+ .name = "version",
+ .attrs = version_attrs,
+};
+
+static int __init gh_sysfs_register(void)
+{
+ int ret;
+
+ ret = sysfs_create_file(hypervisor_kobj, &type_attr.attr);
+ if (ret)
+ return ret;
+
+ ret = sysfs_create_group(hypervisor_kobj, &version_group);
+ if (ret)
+ return ret;
+
+ return sysfs_create_file(hypervisor_kobj, &features_attr.attr);
+}
+
+static void gh_sysfs_unregister(void)
+{
+ sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
+ sysfs_remove_group(hypervisor_kobj, &version_group);
+}
+
+static int __init gunyah_init(void)
+{
+ unsigned long uid[4];
+
+ arch_gh_hypercall(GH_HYPERCALL_CALL_UID, 0, uid[0], uid[1], uid[2], uid[3]);
+
+ if (!(gh_uid_matches(GUNYAH, uid) || gh_uid_matches(QC_HYP, uid)))
+ return 0;
+
+ arch_gh_hypercall(GH_HYPERCALL_HYP_IDENTIFY, 0, gunyah_api.api_info,
+ gunyah_api.flags[0], gunyah_api.flags[1], gunyah_api.flags[2]);
+
+ if (GH_API_INFO_API_VERSION(gunyah_api.api_info) != 1) {
+ pr_warn("Unrecognized gunyah version: %llu. Currently supported: 1\n",
+ GH_API_INFO_API_VERSION(gunyah_api.api_info));
+ return 0;
+ }
+
+ pr_notice("Running under Gunyah hypervisor v%lld/%llx\n",
+ GH_API_INFO_API_VERSION(gunyah_api.api_info),
+ GH_API_INFO_VARIANT(gunyah_api.api_info));
+
+ return gh_sysfs_register();
+}
+module_init(gunyah_init);
+
+static void __exit gunyah_exit(void)
+{
+ gh_sysfs_unregister();
+}
+module_exit(gunyah_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Gunyah Hypervisor Driver");
--
2.25.1