diff mbox series

[05/11] virt: gunyah: Add sysfs nodes

Message ID 20220223233729.1571114-6-quic_eberman@quicinc.com
State New
Headers show
Series Gunyah Hypervisor drivers | expand

Commit Message

Elliot Berman Feb. 23, 2022, 11:37 p.m. UTC
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@quicinc.com>
---
 .../ABI/testing/sysfs-hypervisor-gunyah       |  37 ++++++
 MAINTAINERS                                   |   2 +
 arch/arm64/include/asm/gunyah/hypercall.h     |   2 +
 drivers/virt/Kconfig                          |   2 +
 drivers/virt/Makefile                         |   1 +
 drivers/virt/gunyah/Kconfig                   |  13 ++
 drivers/virt/gunyah/Makefile                  |   4 +
 drivers/virt/gunyah/sysfs.c                   | 116 ++++++++++++++++++
 8 files changed, 177 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 mbox series

Patch

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@vger.kernel.org
+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@vger.kernel.org
+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@vger.kernel.org
+Description:	If running under Gunyah:
+		The Gunyah API version.
+
+What:		/sys/hypervisor/version/variant
+Date:		April 2020
+KernelVersion:	5.17
+Contact:	linux-arm-msm@vger.kernel.org
+Description:	If running under Gunyah:
+		The Gunyah variant (build) version.
\ No newline at end of file
diff --git a/MAINTAINERS b/MAINTAINERS
index 59e7070f726a..10c59c8767ff 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8400,9 +8400,11 @@  M:	Elliot Berman <quic_eberman@quicinc.com>
 M:	Murali Nalajala <quic_mnalajal@quicinc.com>
 L:	linux-arm-msm@vger.kernel.org
 S:	Maintained
+F:	Documentation/ABI/testing/sysfs-hypervisor-gunyah
 F:	Documentation/devicetree/bindings/gunyah/
 F:	Documentation/virt/gunyah/
 F:	arch/arm64/include/asm/gunyah/
+F:	drivers/virt/gunyah/
 F:	include/linux/gunyah.h
 
 H8/300 ARCHITECTURE
diff --git a/arch/arm64/include/asm/gunyah/hypercall.h b/arch/arm64/include/asm/gunyah/hypercall.h
index 626163500e32..a8e68ece074e 100644
--- a/arch/arm64/include/asm/gunyah/hypercall.h
+++ b/arch/arm64/include/asm/gunyah/hypercall.h
@@ -7,6 +7,8 @@ 
 
 #include <linux/types.h>
 
+#define GH_HYPERCALL_HYP_IDENTIFY		0x6000
+
 #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 8061e8ef449f..823663d67a95 100644
--- a/drivers/virt/Kconfig
+++ b/drivers/virt/Kconfig
@@ -36,4 +36,6 @@  source "drivers/virt/vboxguest/Kconfig"
 source "drivers/virt/nitro_enclaves/Kconfig"
 
 source "drivers/virt/acrn/Kconfig"
+
+source "drivers/virt/gunyah/Kconfig"
 endif
diff --git a/drivers/virt/Makefile b/drivers/virt/Makefile
index 3e272ea60cd9..ca2141b6837e 100644
--- a/drivers/virt/Makefile
+++ b/drivers/virt/Makefile
@@ -5,6 +5,7 @@ 
 
 obj-$(CONFIG_FSL_HV_MANAGER)	+= fsl_hypervisor.o
 obj-y				+= vboxguest/
+obj-$(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..3d22f08360db
--- /dev/null
+++ b/drivers/virt/gunyah/sysfs.c
@@ -0,0 +1,116 @@ 
+// 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>
+
+#include "gunyah_private.h"
+
+#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)
+{
+	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;
+	}
+
+	return gh_sysfs_register();
+}
+module_init(gunyah_init);
+
+static void __exit gunyah_exit(void)
+{
+	gh_sysfs_unregister();
+}
+module_exit(gunyah_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Gunyah Hypervisor Driver");