@@ -237,3 +237,5 @@ source "arch/arm/platforms/Kconfig"
source "common/Kconfig"
source "drivers/Kconfig"
+
+source "arch/arm/tee/Kconfig"
@@ -649,7 +649,8 @@ int arch_sanitise_domain_config(struct xen_domctl_createdomain *config)
return -EINVAL;
}
- if ( config->arch.tee_type != XEN_DOMCTL_CONFIG_TEE_NONE )
+ if ( config->arch.tee_type != XEN_DOMCTL_CONFIG_TEE_NONE &&
+ config->arch.tee_type != tee_get_type() )
{
dprintk(XENLOG_INFO, "Unsupported TEE type\n");
return -EINVAL;
new file mode 100644
@@ -0,0 +1,4 @@
+config OPTEE
+ bool "Enable OP-TEE mediator"
+ default n
+ depends on TEE
@@ -1 +1,2 @@
obj-y += tee.o
+obj-$(CONFIG_OPTEE) += optee.o
new file mode 100644
@@ -0,0 +1,166 @@
+/*
+ * xen/arch/arm/tee/optee.c
+ *
+ * OP-TEE mediator. It sits in between OP-TEE and guests and performs
+ * actual calls to OP-TEE when some guest tries to interact with
+ * OP-TEE. As OP-TEE does not know about second stage MMU translation,
+ * mediator does this translation and performs other housekeeping tasks.
+ *
+ * OP-TEE ABI/protocol is described in two header files:
+ * - optee_smc.h provides information about SMCs: all possible calls,
+ * register allocation and return codes.
+ * - optee_msg.h provides format for messages that are passed with
+ * standard call OPTEE_SMC_CALL_WITH_ARG.
+ *
+ * Volodymyr Babchuk <volodymyr_babchuk@epam.com>
+ * Copyright (c) 2018-2019 EPAM Systems.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <xen/device_tree.h>
+#include <xen/sched.h>
+
+#include <asm/smccc.h>
+#include <asm/tee/tee.h>
+#include <asm/tee/optee_msg.h>
+#include <asm/tee/optee_smc.h>
+
+/* Client ID 0 is reserved for the hypervisor itself */
+#define OPTEE_CLIENT_ID(domain) ((domain)->domain_id + 1)
+
+/* Domain context */
+struct optee_domain {
+};
+
+static bool optee_probe(void)
+{
+ struct dt_device_node *node;
+ struct arm_smccc_res resp;
+
+ /* Check for entry in dtb */
+ node = dt_find_compatible_node(NULL, NULL, "linaro,optee-tz");
+ if ( !node )
+ return false;
+
+ /* Check UID */
+ arm_smccc_smc(ARM_SMCCC_CALL_UID_FID(TRUSTED_OS_END), &resp);
+
+ if ( (uint32_t)resp.a0 != OPTEE_MSG_UID_0 ||
+ (uint32_t)resp.a1 != OPTEE_MSG_UID_1 ||
+ (uint32_t)resp.a2 != OPTEE_MSG_UID_2 ||
+ (uint32_t)resp.a3 != OPTEE_MSG_UID_3 )
+ return false;
+
+ return true;
+}
+
+static int optee_domain_init(struct domain *d)
+{
+ struct arm_smccc_res resp;
+ struct optee_domain *ctx;
+
+ ctx = xzalloc(struct optee_domain);
+ if ( !ctx )
+ return -ENOMEM;
+
+ /*
+ * Inform OP-TEE about a new guest. This is a "Fast" call in
+ * terms of OP-TEE. This basically means that it can't be
+ * preempted, because there is no thread allocated for it in
+ * OP-TEE. No blocking calls can be issued and interrupts are
+ * disabled.
+ *
+ * a7 should be 0, so we can't skip last 6 parameters of arm_smccc_smc()
+ */
+ arm_smccc_smc(OPTEE_SMC_VM_CREATED, OPTEE_CLIENT_ID(d), 0, 0, 0, 0, 0, 0,
+ &resp);
+ if ( resp.a0 != OPTEE_SMC_RETURN_OK )
+ {
+ printk(XENLOG_WARNING "%pd: Unable to create OPTEE client: rc = 0x%X\n",
+ d, (uint32_t)resp.a0);
+
+ xfree(ctx);
+
+ return -ENODEV;
+ }
+
+ d->arch.tee = ctx;
+
+ return 0;
+}
+
+static int optee_relinquish_resources(struct domain *d)
+{
+ struct arm_smccc_res resp;
+
+ if ( !d->arch.tee )
+ return 0;
+
+ /*
+ * Inform OP-TEE that domain is shutting down. This is
+ * also a fast SMC call, like OPTEE_SMC_VM_CREATED, so
+ * it is also non-preemptible.
+ * At this time all domain VCPUs should be stopped. OP-TEE
+ * relies on this.
+ *
+ * a7 should be 0, so we can't skip last 6 parameters of arm_smccc_smc()
+ */
+ arm_smccc_smc(OPTEE_SMC_VM_DESTROYED, OPTEE_CLIENT_ID(d), 0, 0, 0, 0, 0, 0,
+ &resp);
+
+ XFREE(d->arch.tee);
+
+ return 0;
+}
+
+static bool optee_handle_call(struct cpu_user_regs *regs)
+{
+ if ( !current->domain->arch.tee )
+ return false;
+
+ switch ( get_user_reg(regs, 0) )
+ {
+ case OPTEE_SMC_CALLS_COUNT:
+ case OPTEE_SMC_CALLS_UID:
+ case OPTEE_SMC_CALLS_REVISION:
+ case OPTEE_SMC_CALL_GET_OS_UUID:
+ case OPTEE_SMC_CALL_GET_OS_REVISION:
+ case OPTEE_SMC_ENABLE_SHM_CACHE:
+ case OPTEE_SMC_DISABLE_SHM_CACHE:
+ case OPTEE_SMC_GET_SHM_CONFIG:
+ case OPTEE_SMC_EXCHANGE_CAPABILITIES:
+ case OPTEE_SMC_CALL_WITH_ARG:
+ case OPTEE_SMC_CALL_RETURN_FROM_RPC:
+ set_user_reg(regs, 0, OPTEE_SMC_RETURN_ENOTAVAIL);
+ return true;
+
+ default:
+ return false;
+ }
+}
+
+static const struct tee_mediator_ops optee_ops =
+{
+ .probe = optee_probe,
+ .domain_init = optee_domain_init,
+ .relinquish_resources = optee_relinquish_resources,
+ .handle_call = optee_handle_call,
+};
+
+REGISTER_TEE_MEDIATOR(optee, "OP-TEE", XEN_DOMCTL_CONFIG_TEE_OPTEE, &optee_ops);
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
@@ -98,6 +98,9 @@ struct arch_domain
struct vpl011 vpl011;
#endif
+#ifdef CONFIG_TEE
+ void *tee;
+#endif
} __cacheline_aligned;
struct arch_vcpu
@@ -305,6 +305,7 @@ DEFINE_XEN_GUEST_HANDLE(vcpu_guest_context_t);
#define XEN_DOMCTL_CONFIG_GIC_V2 1
#define XEN_DOMCTL_CONFIG_GIC_V3 2
#define XEN_DOMCTL_CONFIG_TEE_NONE 0
+#define XEN_DOMCTL_CONFIG_TEE_OPTEE 1
struct xen_arch_domainconfig {
/* IN/OUT */
uint8_t gic_version;
Add very basic OP-TEE mediator. It can probe for OP-TEE presence, tell it about domain creation/destruction and then return an error to all calls to the guest. This code issues two non-preemptible calls to OP-TEE: to create and to destroy client context. They can't block in OP-TEE, as they are considered "fast calls" in terms of ARM SMCCC. Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com> --- All the patches to optee.c should be merged together. They were split to ease up review. But they depend heavily on each other. Changes from v4: - Removed OPTEE_ENABLED macro. Empty (for now) struct optee_domain is used instead. - Removed forward_call() function, mediator now will return OPTEE_SMC_RETURN_ENOTAVAIL for all unimplemented calls - Fixed mistake when OPTEE_SMC_FUNCID_GET_OS_REVISION instead of OPTEE_SMC_CALL_GET_OS_REVISION was used - OP-TEE is informed about domain destruction in optee_relinquish_resources() - removed optee_domain_destroy() function because all job is done in the optee_relinquish_resources() function Changes from v3: - Introduced optee_relinquish_resources() function to free mediator resources in a more controllable way Changes from v2: - Fixed coding style - Introduced tee/Kconfig - Fixed error messages --- xen/arch/arm/Kconfig | 2 + xen/arch/arm/domain.c | 3 +- xen/arch/arm/tee/Kconfig | 4 + xen/arch/arm/tee/Makefile | 1 + xen/arch/arm/tee/optee.c | 166 ++++++++++++++++++++++++++++++++++ xen/include/asm-arm/domain.h | 3 + xen/include/public/arch-arm.h | 1 + 7 files changed, 179 insertions(+), 1 deletion(-) create mode 100644 xen/arch/arm/tee/Kconfig create mode 100644 xen/arch/arm/tee/optee.c