diff options
author | Arnd Bergmann <arnd@arndb.de> | 2023-12-22 10:43:18 +0000 |
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committer | Arnd Bergmann <arnd@arndb.de> | 2023-12-22 10:43:19 +0000 |
commit | 95c1e57a384be88431ac031560cc2ae50d021d2d (patch) | |
tree | e2112ab62d485d00e673b3d3249d5f2fa8d1fc8f | |
parent | 9d0e3c5a3d89bbd77c671a84301c38e0a71bfa14 (diff) | |
parent | d0476a59de064205f4aaa8f7c6d6f32bc28a44d4 (diff) | |
download | lwn-95c1e57a384be88431ac031560cc2ae50d021d2d.tar.gz lwn-95c1e57a384be88431ac031560cc2ae50d021d2d.zip |
Merge tag 'ffa-notif-for-v6.8' of https://git.linaro.org/people/jens.wiklander/linux-tee into soc/drivers
OP-TEE: asynchronous notifications with FF-A
Add support for asynchronous notifications in the OP-TEE FF-A driver. This
is the FF-A counterpart to the asynchronous notifications already
available in the OP-TEE SMC ABI.
* tag 'ffa-notif-for-v6.8' of https://git.linaro.org/people/jens.wiklander/linux-tee:
optee: ffa_abi: add asynchronous notifications
optee: provide optee_do_bottom_half() as a common function
Link: https://lore.kernel.org/r/20231211105249.GA587253@rayden
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
-rw-r--r-- | drivers/tee/optee/call.c | 31 | ||||
-rw-r--r-- | drivers/tee/optee/ffa_abi.c | 93 | ||||
-rw-r--r-- | drivers/tee/optee/optee_ffa.h | 28 | ||||
-rw-r--r-- | drivers/tee/optee/optee_private.h | 9 | ||||
-rw-r--r-- | drivers/tee/optee/smc_abi.c | 36 |
5 files changed, 155 insertions, 42 deletions
diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c index b04c49c69619..a91e50be11be 100644 --- a/drivers/tee/optee/call.c +++ b/drivers/tee/optee/call.c @@ -1,6 +1,6 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * Copyright (c) 2015-2021, Linaro Limited + * Copyright (c) 2015-2021, 2023 Linaro Limited */ #include <linux/device.h> #include <linux/err.h> @@ -640,3 +640,32 @@ int optee_check_mem_type(unsigned long start, size_t num_pages) return rc; } + +static int simple_call_with_arg(struct tee_context *ctx, u32 cmd) +{ + struct optee *optee = tee_get_drvdata(ctx->teedev); + struct optee_shm_arg_entry *entry; + struct optee_msg_arg *msg_arg; + struct tee_shm *shm; + u_int offs; + + msg_arg = optee_get_msg_arg(ctx, 0, &entry, &shm, &offs); + if (IS_ERR(msg_arg)) + return PTR_ERR(msg_arg); + + msg_arg->cmd = cmd; + optee->ops->do_call_with_arg(ctx, shm, offs, false); + + optee_free_msg_arg(ctx, entry, offs); + return 0; +} + +int optee_do_bottom_half(struct tee_context *ctx) +{ + return simple_call_with_arg(ctx, OPTEE_MSG_CMD_DO_BOTTOM_HALF); +} + +int optee_stop_async_notif(struct tee_context *ctx) +{ + return simple_call_with_arg(ctx, OPTEE_MSG_CMD_STOP_ASYNC_NOTIF); +} diff --git a/drivers/tee/optee/ffa_abi.c b/drivers/tee/optee/ffa_abi.c index d73396ed5b93..ecb5eb079408 100644 --- a/drivers/tee/optee/ffa_abi.c +++ b/drivers/tee/optee/ffa_abi.c @@ -1,6 +1,6 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * Copyright (c) 2021, Linaro Limited + * Copyright (c) 2021, 2023 Linaro Limited */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt @@ -695,7 +695,8 @@ static bool optee_ffa_api_is_compatbile(struct ffa_device *ffa_dev, static bool optee_ffa_exchange_caps(struct ffa_device *ffa_dev, const struct ffa_ops *ops, u32 *sec_caps, - unsigned int *rpc_param_count) + unsigned int *rpc_param_count, + unsigned int *max_notif_value) { struct ffa_send_direct_data data = { OPTEE_FFA_EXCHANGE_CAPABILITIES }; int rc; @@ -712,10 +713,39 @@ static bool optee_ffa_exchange_caps(struct ffa_device *ffa_dev, *rpc_param_count = (u8)data.data1; *sec_caps = data.data2; + if (data.data3) + *max_notif_value = data.data3; + else + *max_notif_value = OPTEE_DEFAULT_MAX_NOTIF_VALUE; return true; } +static void notif_callback(int notify_id, void *cb_data) +{ + struct optee *optee = cb_data; + + if (notify_id == optee->ffa.bottom_half_value) + optee_do_bottom_half(optee->ctx); + else + optee_notif_send(optee, notify_id); +} + +static int enable_async_notif(struct optee *optee) +{ + struct ffa_device *ffa_dev = optee->ffa.ffa_dev; + struct ffa_send_direct_data data = { + .data0 = OPTEE_FFA_ENABLE_ASYNC_NOTIF, + .data1 = optee->ffa.bottom_half_value, + }; + int rc; + + rc = ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &data); + if (rc) + return rc; + return data.data0; +} + static void optee_ffa_get_version(struct tee_device *teedev, struct tee_ioctl_version_data *vers) { @@ -778,7 +808,11 @@ static const struct optee_ops optee_ffa_ops = { static void optee_ffa_remove(struct ffa_device *ffa_dev) { struct optee *optee = ffa_dev_get_drvdata(ffa_dev); + u32 bottom_half_id = optee->ffa.bottom_half_value; + if (bottom_half_id != U32_MAX) + ffa_dev->ops->notifier_ops->notify_relinquish(ffa_dev, + bottom_half_id); optee_remove_common(optee); mutex_destroy(&optee->ffa.mutex); @@ -787,9 +821,51 @@ static void optee_ffa_remove(struct ffa_device *ffa_dev) kfree(optee); } +static int optee_ffa_async_notif_init(struct ffa_device *ffa_dev, + struct optee *optee) +{ + bool is_per_vcpu = false; + u32 notif_id = 0; + int rc; + + while (true) { + rc = ffa_dev->ops->notifier_ops->notify_request(ffa_dev, + is_per_vcpu, + notif_callback, + optee, + notif_id); + if (!rc) + break; + /* + * -EACCES means that the notification ID was + * already bound, try the next one as long as we + * haven't reached the max. Any other error is a + * permanent error, so skip asynchronous + * notifications in that case. + */ + if (rc != -EACCES) + return rc; + notif_id++; + if (notif_id >= OPTEE_FFA_MAX_ASYNC_NOTIF_VALUE) + return rc; + } + optee->ffa.bottom_half_value = notif_id; + + rc = enable_async_notif(optee); + if (rc < 0) { + ffa_dev->ops->notifier_ops->notify_relinquish(ffa_dev, + notif_id); + optee->ffa.bottom_half_value = U32_MAX; + } + + return rc; +} + static int optee_ffa_probe(struct ffa_device *ffa_dev) { + const struct ffa_notifier_ops *notif_ops; const struct ffa_ops *ffa_ops; + unsigned int max_notif_value; unsigned int rpc_param_count; struct tee_shm_pool *pool; struct tee_device *teedev; @@ -800,12 +876,13 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) int rc; ffa_ops = ffa_dev->ops; + notif_ops = ffa_ops->notifier_ops; if (!optee_ffa_api_is_compatbile(ffa_dev, ffa_ops)) return -EINVAL; if (!optee_ffa_exchange_caps(ffa_dev, ffa_ops, &sec_caps, - &rpc_param_count)) + &rpc_param_count, &max_notif_value)) return -EINVAL; if (sec_caps & OPTEE_FFA_SEC_CAP_ARG_OFFSET) arg_cache_flags |= OPTEE_SHM_ARG_SHARED; @@ -823,6 +900,7 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) optee->ops = &optee_ffa_ops; optee->ffa.ffa_dev = ffa_dev; + optee->ffa.bottom_half_value = U32_MAX; optee->rpc_param_count = rpc_param_count; teedev = tee_device_alloc(&optee_ffa_clnt_desc, NULL, optee->pool, @@ -866,6 +944,12 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) rc = optee_notif_init(optee, OPTEE_DEFAULT_MAX_NOTIF_VALUE); if (rc) goto err_close_ctx; + if (sec_caps & OPTEE_FFA_SEC_CAP_ASYNC_NOTIF) { + rc = optee_ffa_async_notif_init(ffa_dev, optee); + if (rc < 0) + pr_err("Failed to initialize async notifications: %d", + rc); + } rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES); if (rc) @@ -876,6 +960,9 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) err_unregister_devices: optee_unregister_devices(); + if (optee->ffa.bottom_half_value != U32_MAX) + notif_ops->notify_relinquish(ffa_dev, + optee->ffa.bottom_half_value); optee_notif_uninit(optee); err_close_ctx: teedev_close_context(ctx); diff --git a/drivers/tee/optee/optee_ffa.h b/drivers/tee/optee/optee_ffa.h index 97266243deaa..5db779dc00de 100644 --- a/drivers/tee/optee/optee_ffa.h +++ b/drivers/tee/optee/optee_ffa.h @@ -1,6 +1,6 @@ /* SPDX-License-Identifier: BSD-2-Clause */ /* - * Copyright (c) 2019-2021, Linaro Limited + * Copyright (c) 2019-2021, 2023 Linaro Limited */ /* @@ -73,7 +73,7 @@ * * Call register usage: * w3: Service ID, OPTEE_FFA_EXCHANGE_CAPABILITIES - * w4-w7: Note used (MBZ) + * w4-w7: Not used (MBZ) * * Return register usage: * w3: Error code, 0 on success @@ -82,14 +82,16 @@ * OPTEE_FFA_YIELDING_CALL_WITH_ARG. * Bit[31:8]: Reserved (MBZ) * w5: Bitfield of secure world capabilities OPTEE_FFA_SEC_CAP_* below, - * unused bits MBZ. - * w6-w7: Not used (MBZ) + * w6: The maximum secure world notification number + * w7: Not used (MBZ) */ /* * Secure world supports giving an offset into the argument shared memory * object, see also OPTEE_FFA_YIELDING_CALL_WITH_ARG */ #define OPTEE_FFA_SEC_CAP_ARG_OFFSET BIT(0) +/* OP-TEE supports asynchronous notification via FF-A */ +#define OPTEE_FFA_SEC_CAP_ASYNC_NOTIF BIT(1) #define OPTEE_FFA_EXCHANGE_CAPABILITIES OPTEE_FFA_BLOCKING_CALL(2) @@ -109,6 +111,24 @@ #define OPTEE_FFA_UNREGISTER_SHM OPTEE_FFA_BLOCKING_CALL(3) /* + * Inform OP-TEE that the normal world is able to receive asynchronous + * notifications. + * + * Call register usage: + * w3: Service ID, OPTEE_FFA_ENABLE_ASYNC_NOTIF + * w4: Notification value to request bottom half processing, should be + * less than OPTEE_FFA_MAX_ASYNC_NOTIF_VALUE. + * w5-w7: Not used (MBZ) + * + * Return register usage: + * w3: Error code, 0 on success + * w4-w7: Note used (MBZ) + */ +#define OPTEE_FFA_ENABLE_ASYNC_NOTIF OPTEE_FFA_BLOCKING_CALL(5) + +#define OPTEE_FFA_MAX_ASYNC_NOTIF_VALUE 64 + +/* * Call with struct optee_msg_arg as argument in the supplied shared memory * with a zero internal offset and normal cached memory attributes. * Register usage: diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h index 7832ccefe6d0..a5a2d6e63782 100644 --- a/drivers/tee/optee/optee_private.h +++ b/drivers/tee/optee/optee_private.h @@ -1,6 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0-only */ /* - * Copyright (c) 2015-2021, Linaro Limited + * Copyright (c) 2015-2021, 2023 Linaro Limited */ #ifndef OPTEE_PRIVATE_H @@ -147,12 +147,14 @@ struct optee_smc { * struct optee_ffa_data - FFA communication struct * @ffa_dev FFA device, contains the destination id, the id of * OP-TEE in secure world - * @ffa_ops FFA operations + * @bottom_half_value Notification ID used for bottom half signalling or + * U32_MAX if unused * @mutex Serializes access to @global_ids * @global_ids FF-A shared memory global handle translation */ struct optee_ffa { struct ffa_device *ffa_dev; + u32 bottom_half_value; /* Serializes access to @global_ids */ struct mutex mutex; struct rhashtable global_ids; @@ -346,6 +348,9 @@ void optee_rpc_cmd_free_suppl(struct tee_context *ctx, struct tee_shm *shm); void optee_rpc_cmd(struct tee_context *ctx, struct optee *optee, struct optee_msg_arg *arg); +int optee_do_bottom_half(struct tee_context *ctx); +int optee_stop_async_notif(struct tee_context *ctx); + /* * Small helpers */ diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c index 3b60acc15cf0..e158f3136c26 100644 --- a/drivers/tee/optee/smc_abi.c +++ b/drivers/tee/optee/smc_abi.c @@ -1,6 +1,6 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * Copyright (c) 2015-2021, Linaro Limited + * Copyright (c) 2015-2021, 2023 Linaro Limited * Copyright (c) 2016, EPAM Systems */ @@ -967,34 +967,6 @@ 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_shm_arg_entry *entry; - struct optee_msg_arg *msg_arg; - struct tee_shm *shm; - u_int offs; - - msg_arg = optee_get_msg_arg(ctx, 0, &entry, &shm, &offs); - if (IS_ERR(msg_arg)) - return PTR_ERR(msg_arg); - - msg_arg->cmd = cmd; - optee_smc_do_call_with_arg(ctx, shm, offs, false); - - optee_free_msg_arg(ctx, entry, offs); - 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. Asynchronous notification */ @@ -1050,7 +1022,7 @@ static irqreturn_t notif_irq_thread_fn(int irq, void *dev_id) { struct optee *optee = dev_id; - optee_smc_do_bottom_half(optee->ctx); + optee_do_bottom_half(optee->ctx); return IRQ_HANDLED; } @@ -1088,7 +1060,7 @@ static void notif_pcpu_irq_work_fn(struct work_struct *work) notif_pcpu_work); struct optee *optee = container_of(optee_smc, struct optee, smc); - optee_smc_do_bottom_half(optee->ctx); + optee_do_bottom_half(optee->ctx); } static int init_pcpu_irq(struct optee *optee, u_int irq) @@ -1160,7 +1132,7 @@ static void uninit_pcpu_irq(struct optee *optee) static void optee_smc_notif_uninit_irq(struct optee *optee) { if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_ASYNC_NOTIF) { - optee_smc_stop_async_notif(optee->ctx); + optee_stop_async_notif(optee->ctx); if (optee->smc.notif_irq) { if (irq_is_percpu_devid(optee->smc.notif_irq)) uninit_pcpu_irq(optee); |