@@ -318,6 +318,13 @@ struct optee_msg_arg {
* [in] param[0].u.rmem.shm_ref holds shared memory reference
* [in] param[0].u.rmem.offs 0
* [in] param[0].u.rmem.size 0
+ *
+ * OPTEE_MSG_CMD_DO_BOTTOM_HALF does the scheduled bottom half processing
+ * of a driver.
+ *
+ * OPTEE_MSG_CMD_STOP_ASYNC_NOTIF informs secure world that from now is
+ * normal world unable to process asynchronous notifications. Typically
+ * used when the driver is shut down.
*/
#define OPTEE_MSG_CMD_OPEN_SESSION 0
#define OPTEE_MSG_CMD_INVOKE_COMMAND 1
@@ -325,6 +332,8 @@ struct optee_msg_arg {
#define OPTEE_MSG_CMD_CANCEL 3
#define OPTEE_MSG_CMD_REGISTER_SHM 4
#define OPTEE_MSG_CMD_UNREGISTER_SHM 5
+#define OPTEE_MSG_CMD_DO_BOTTOM_HALF 6
+#define OPTEE_MSG_CMD_STOP_ASYNC_NOTIF 7
#define OPTEE_MSG_FUNCID_CALL_WITH_ARG 0x0004
#endif /* _OPTEE_MSG_H */
@@ -53,6 +53,7 @@ struct optee_call_queue {
struct optee_notif {
u_int max_key;
+ struct tee_context *ctx;
/* Serializes access to the elements below in this struct */
spinlock_t lock;
struct list_head db;
@@ -88,6 +89,7 @@ struct optee_smc {
optee_invoke_fn *invoke_fn;
void *memremaped_shm;
u32 sec_caps;
+ unsigned int notif_irq;
};
/**
@@ -107,6 +107,12 @@ struct optee_smc_call_get_os_revision_result {
/*
* Call with struct optee_msg_arg as argument
*
+ * When calling this function normal world has a few responsibilities:
+ * 1. It must be able to handle eventual RPCs
+ * 2. Non-secure interrupts should not be masked
+ * 3. If asynchronous notifications has been negotiated successfully, then
+ * asynchronous notifications should be unmasked during this call.
+ *
* Call register usage:
* a0 SMC Function ID, OPTEE_SMC*CALL_WITH_ARG
* a1 Upper 32 bits of a 64-bit physical pointer to a struct optee_msg_arg
@@ -195,7 +201,8 @@ struct optee_smc_get_shm_config_result {
* Normal return register usage:
* a0 OPTEE_SMC_RETURN_OK
* a1 bitfield of secure world capabilities OPTEE_SMC_SEC_CAP_*
- * a2-7 Preserved
+ * a2 The maximum secure world notification number
+ * a3-7 Preserved
*
* Error return register usage:
* a0 OPTEE_SMC_RETURN_ENOTAVAIL, can't use the capabilities from normal world
@@ -218,6 +225,8 @@ struct optee_smc_get_shm_config_result {
#define OPTEE_SMC_SEC_CAP_VIRTUALIZATION BIT(3)
/* Secure world supports Shared Memory with a NULL reference */
#define OPTEE_SMC_SEC_CAP_MEMREF_NULL BIT(4)
+/* Secure world supports asynchronous notification of normal world */
+#define OPTEE_SMC_SEC_CAP_ASYNC_NOTIF BIT(5)
#define OPTEE_SMC_FUNCID_EXCHANGE_CAPABILITIES 9
#define OPTEE_SMC_EXCHANGE_CAPABILITIES \
@@ -226,8 +235,8 @@ struct optee_smc_get_shm_config_result {
struct optee_smc_exchange_capabilities_result {
unsigned long status;
unsigned long capabilities;
+ unsigned long max_notif_value;
unsigned long reserved0;
- unsigned long reserved1;
};
/*
@@ -319,6 +328,68 @@ struct optee_smc_disable_shm_cache_result {
#define OPTEE_SMC_GET_THREAD_COUNT \
OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_GET_THREAD_COUNT)
+/*
+ * Inform OP-TEE that normal world is able to receive asynchronous
+ * notifications.
+ *
+ * Call requests usage:
+ * a0 SMC Function ID, OPTEE_SMC_ENABLE_ASYNC_NOTIF
+ * a1-6 Not used
+ * a7 Hypervisor Client ID register
+ *
+ * Normal return register usage:
+ * a0 OPTEE_SMC_RETURN_OK
+ * a1-7 Preserved
+ *
+ * Not supported return register usage:
+ * a0 OPTEE_SMC_RETURN_ENOTAVAIL
+ * a1-7 Preserved
+ */
+#define OPTEE_SMC_FUNCID_ENABLE_ASYNC_NOTIF 16
+#define OPTEE_SMC_ENABLE_ASYNC_NOTIF \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_ENABLE_ASYNC_NOTIF)
+
+/*
+ * Retrieve a value of notifications pending since the last call of this
+ * function.
+ *
+ * OP-TEE keeps a record of all posted values. When an interrupts is
+ * received which indicates that there are posed values this function
+ * should be called until all pended values have been retrieved. When a
+ * value is retrieved, it's cleared from the record in secure world.
+ *
+ * Call requests usage:
+ * a0 SMC Function ID, OPTEE_SMC_GET_ASYNC_NOTIF_VALUE
+ * a1-6 Not used
+ * a7 Hypervisor Client ID register
+ *
+ * Normal return register usage:
+ * a0 OPTEE_SMC_RETURN_OK
+ * a1 value
+ * a2 Bit[0]: OPTEE_SMC_ASYNC_NOTIF_VALUE_VALID if the value in a1 is
+ * valid, else 0 if no values where pending
+ * a2 Bit[1]: OPTEE_SMC_ASYNC_NOTIF_VALUE_PENDING if another value is
+ * pending, else 0.
+ * Bit[31:2]: MBZ
+ * a3-7 Preserved
+ *
+ * Not supported return register usage:
+ * a0 OPTEE_SMC_RETURN_ENOTAVAIL
+ * a1-7 Preserved
+ */
+#define OPTEE_SMC_ASYNC_NOTIF_VALUE_VALID BIT(0)
+#define OPTEE_SMC_ASYNC_NOTIF_VALUE_PENDING BIT(1)
+
+/*
+ * Notification that OP-TEE expects a yielding call to do some bottom half
+ * work in a driver.
+ */
+#define OPTEE_SMC_ASYNC_NOTIF_VALUE_DO_BOTTOM_HALF 0
+
+#define OPTEE_SMC_FUNCID_GET_ASYNC_NOTIF_VALUE 17
+#define OPTEE_SMC_GET_ASYNC_NOTIF_VALUE \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_GET_ASYNC_NOTIF_VALUE)
+
/*
* Resume from RPC (for example after processing a foreign interrupt)
*
@@ -8,13 +8,16 @@
#include <linux/arm-smccc.h>
#include <linux/errno.h>
+#include <linux/interrupt.h>
#include <linux/io.h>
-#include <linux/sched.h>
+#include <linux/irqdomain.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
+#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/tee_drv.h>
@@ -34,7 +37,8 @@
* 2. Low level support functions to register shared memory in secure world
* 3. Dynamic shared memory pool based on alloc_pages()
* 4. Do a normal scheduled call into secure world
- * 5. Driver initialization.
+ * 5. Asynchronous notifcation
+ * 6. Driver initialization.
*/
#define OPTEE_SHM_NUM_PRIV_PAGES CONFIG_OPTEE_SHM_NUM_PRIV_PAGES
@@ -875,8 +879,135 @@ static int optee_smc_do_call_with_arg(struct tee_context *ctx,
return rc;
}
+static int simple_call_with_arg(struct tee_context *ctx, u32 cmd)
+{
+ struct optee_msg_arg *msg_arg;
+ struct tee_shm *shm;
+
+ shm = optee_get_msg_arg(ctx, 0, &msg_arg);
+ if (IS_ERR(shm))
+ return PTR_ERR(shm);
+
+ msg_arg->cmd = cmd;
+ optee_smc_do_call_with_arg(ctx, shm);
+
+ tee_shm_free(shm);
+ return 0;
+}
+
+static int optee_smc_do_bottom_half(struct tee_context *ctx)
+{
+ return simple_call_with_arg(ctx, OPTEE_MSG_CMD_DO_BOTTOM_HALF);
+}
+
+static int optee_smc_stop_async_notif(struct tee_context *ctx)
+{
+ return simple_call_with_arg(ctx, OPTEE_MSG_CMD_STOP_ASYNC_NOTIF);
+}
+
/*
- * 5. Driver initialization
+ * 5. Asynchronous notifcation
+ */
+
+static u32 get_async_notif_value(optee_invoke_fn *invoke_fn, bool *value_valid,
+ bool *value_pending)
+{
+ struct arm_smccc_res res;
+
+ invoke_fn(OPTEE_SMC_GET_ASYNC_NOTIF_VALUE, 0, 0, 0, 0, 0, 0, 0, &res);
+
+ if (res.a0)
+ return 0;
+ *value_valid = (res.a2 & OPTEE_SMC_ASYNC_NOTIF_VALUE_VALID);
+ *value_pending = (res.a2 & OPTEE_SMC_ASYNC_NOTIF_VALUE_PENDING);
+ return res.a1;
+}
+
+static irqreturn_t notif_irq_handler(int irq, void *dev_id)
+{
+ struct optee *optee = dev_id;
+ bool do_bottom_half = false;
+ bool value_valid;
+ bool value_pending;
+ u32 value;
+
+ do {
+ value = get_async_notif_value(optee->smc.invoke_fn,
+ &value_valid, &value_pending);
+ if (!value_valid)
+ break;
+
+ if (value == OPTEE_SMC_ASYNC_NOTIF_VALUE_DO_BOTTOM_HALF)
+ do_bottom_half = true;
+ else
+ optee_notif_send(optee, value);
+ } while (value_pending);
+
+ if (do_bottom_half)
+ return IRQ_WAKE_THREAD;
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t notif_irq_thread_fn(int irq, void *dev_id)
+{
+ struct optee *optee = dev_id;
+
+ optee_smc_do_bottom_half(optee->notif.ctx);
+
+ return IRQ_HANDLED;
+}
+
+static int optee_smc_notif_init_irq(struct optee *optee, u_int irq)
+{
+ struct tee_context *ctx;
+ int rc;
+
+ ctx = teedev_open(optee->teedev);
+ if (IS_ERR(ctx))
+ return PTR_ERR(ctx);
+
+ optee->notif.ctx = ctx;
+ rc = request_threaded_irq(irq, notif_irq_handler,
+ notif_irq_thread_fn,
+ 0, "optee_notification", optee);
+ if (rc)
+ goto err_close_ctx;
+
+ optee->smc.notif_irq = irq;
+
+ return 0;
+
+err_close_ctx:
+ teedev_close_context(optee->notif.ctx);
+ optee->notif.ctx = NULL;
+
+ return rc;
+}
+
+static void optee_smc_notif_uninit_irq(struct optee *optee)
+{
+ if (optee->notif.ctx) {
+ optee_smc_stop_async_notif(optee->notif.ctx);
+ if (optee->smc.notif_irq) {
+ free_irq(optee->smc.notif_irq, optee);
+ irq_dispose_mapping(optee->smc.notif_irq);
+ }
+
+ /*
+ * The thread normally working with optee->notif.ctx was
+ * stopped with free_irq() above.
+ *
+ * Note we're not using teedev_close_context() or
+ * tee_client_close_context() since we have already called
+ * tee_device_put() while initializing to avoid a circular
+ * reference counting.
+ */
+ teedev_close_context(optee->notif.ctx);
+ }
+}
+
+/*
+ * 6. Driver initialization
*
* During driver inititialization is secure world probed to find out which
* features it supports so the driver can be initialized with a matching
@@ -950,6 +1081,17 @@ static const struct optee_ops optee_ops = {
.from_msg_param = optee_from_msg_param,
};
+static int enable_async_notif(optee_invoke_fn *invoke_fn)
+{
+ struct arm_smccc_res res;
+
+ invoke_fn(OPTEE_SMC_ENABLE_ASYNC_NOTIF, 0, 0, 0, 0, 0, 0, 0, &res);
+
+ if (res.a0)
+ return -EINVAL;
+ return 0;
+}
+
static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn)
{
struct arm_smccc_res res;
@@ -999,7 +1141,7 @@ static bool optee_msg_api_revision_is_compatible(optee_invoke_fn *invoke_fn)
}
static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
- u32 *sec_caps)
+ u32 *sec_caps, u32 *max_notif_value)
{
union {
struct arm_smccc_res smccc;
@@ -1022,6 +1164,11 @@ static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
return false;
*sec_caps = res.result.capabilities;
+ if (*sec_caps & OPTEE_SMC_SEC_CAP_ASYNC_NOTIF)
+ *max_notif_value = res.result.max_notif_value;
+ else
+ *max_notif_value = OPTEE_DEFAULT_MAX_NOTIF_VALUE;
+
return true;
}
@@ -1186,6 +1333,8 @@ static int optee_smc_remove(struct platform_device *pdev)
*/
optee_disable_shm_cache(optee);
+ optee_smc_notif_uninit_irq(optee);
+
optee_remove_common(optee);
if (optee->smc.memremaped_shm)
@@ -1215,6 +1364,7 @@ static int optee_probe(struct platform_device *pdev)
struct optee *optee = NULL;
void *memremaped_shm = NULL;
struct tee_device *teedev;
+ u32 max_notif_value;
u32 sec_caps;
int rc;
@@ -1234,7 +1384,8 @@ static int optee_probe(struct platform_device *pdev)
return -EINVAL;
}
- if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps)) {
+ if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps,
+ &max_notif_value)) {
pr_warn("capabilities mismatch\n");
return -EINVAL;
}
@@ -1257,7 +1408,7 @@ static int optee_probe(struct platform_device *pdev)
optee = kzalloc(sizeof(*optee), GFP_KERNEL);
if (!optee) {
rc = -ENOMEM;
- goto err;
+ goto err_free_pool;
}
optee->ops = &optee_ops;
@@ -1267,24 +1418,24 @@ static int optee_probe(struct platform_device *pdev)
teedev = tee_device_alloc(&optee_clnt_desc, NULL, pool, optee);
if (IS_ERR(teedev)) {
rc = PTR_ERR(teedev);
- goto err;
+ goto err_free_optee;
}
optee->teedev = teedev;
teedev = tee_device_alloc(&optee_supp_desc, NULL, pool, optee);
if (IS_ERR(teedev)) {
rc = PTR_ERR(teedev);
- goto err;
+ goto err_unreg_teedev;
}
optee->supp_teedev = teedev;
rc = tee_device_register(optee->teedev);
if (rc)
- goto err;
+ goto err_unreg_supp_teedev;
rc = tee_device_register(optee->supp_teedev);
if (rc)
- goto err;
+ goto err_unreg_supp_teedev;
mutex_init(&optee->call_queue.mutex);
INIT_LIST_HEAD(&optee->call_queue.waiters);
@@ -1293,10 +1444,27 @@ static int optee_probe(struct platform_device *pdev)
optee->pool = pool;
platform_set_drvdata(pdev, optee);
- rc = optee_notif_init(optee, OPTEE_DEFAULT_MAX_NOTIF_VALUE);
- if (rc) {
- optee_remove(pdev);
- return rc;
+ rc = optee_notif_init(optee, max_notif_value);
+ if (rc)
+ goto err_supp_uninit;
+
+ if (sec_caps & OPTEE_SMC_SEC_CAP_ASYNC_NOTIF) {
+ unsigned int irq;
+
+ rc = platform_get_irq(pdev, 0);
+ if (rc < 0) {
+ pr_err("platform_get_irq: ret %d\n", rc);
+ goto err_notif_uninit;
+ }
+ irq = rc;
+
+ rc = optee_smc_notif_init_irq(optee, irq);
+ if (rc) {
+ irq_dispose_mapping(irq);
+ goto err_notif_uninit;
+ }
+ enable_async_notif(optee->smc.invoke_fn);
+ pr_info("Asynchronous notifications enabled\n");
}
/*
@@ -1314,28 +1482,30 @@ static int optee_probe(struct platform_device *pdev)
pr_info("dynamic shared memory is enabled\n");
rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES);
- if (rc) {
- optee_smc_remove(pdev);
- return rc;
- }
+ if (rc)
+ goto err_disable_shm_cache;
pr_info("initialized driver\n");
return 0;
-err:
- if (optee) {
- /*
- * tee_device_unregister() is safe to call even if the
- * devices hasn't been registered with
- * tee_device_register() yet.
- */
- tee_device_unregister(optee->supp_teedev);
- tee_device_unregister(optee->teedev);
- kfree(optee);
- }
- if (pool)
- tee_shm_pool_free(pool);
- if (memremaped_shm)
- memunmap(memremaped_shm);
+
+err_disable_shm_cache:
+ optee_disable_shm_cache(optee);
+ optee_smc_notif_uninit_irq(optee);
+err_notif_uninit:
+ optee_notif_uninit(optee);
+err_supp_uninit:
+ optee_supp_uninit(&optee->supp);
+ mutex_destroy(&optee->call_queue.mutex);
+err_unreg_supp_teedev:
+ tee_device_unregister(optee->supp_teedev);
+err_unreg_teedev:
+ tee_device_unregister(optee->teedev);
+err_free_optee:
+ kfree(optee);
+err_free_pool:
+ tee_shm_pool_free(pool);
+ if (optee->smc.memremaped_shm)
+ memunmap(optee->smc.memremaped_shm);
return rc;
}