Implements use of per-cpu irq for optee asynchronous notification.
Existing optee async notif implementation allows OP-TEE world to raise an interrupt on which Linux optee driver will query some pending events. This change allows the signaling interrupt to be a per-cpu interrupt as with Arm GIC PPIs. Using a PPI instead of an SPI is useful when no GIC lines are provisioned in the chip design and there are spare PPI lines.
Cc: Jens Wiklander jens.wiklander@linaro.org Cc: Sumit Garg sumit.garg@linaro.org Cc: Marc Zyngier maz@kernel.org
Co-developed-by: Alexandre Torgue alexandre.torgue@foss.st.com Signed-off-by: Alexandre Torgue alexandre.torgue@foss.st.com Signed-off-by: Etienne Carriere etienne.carriere@linaro.org --- Changes since v5: - Removed spurious __percpu attributes reported by kernel test robot (https://lore.kernel.org/lkml/202303190039.RsU7kCIu-lkp@intel.com/).
Changes since v4: - Used cpuhp_setup_state()/cpuhp_remove_state() to enable/disable the per-cpu interrupt and let CPU hotplug also manage it. - Added a call to destroy_workqueue() that was missing in uninit_pcpu_irq(). - Rephrased commit message.
Changes since v3: - Fixed typo in commit message. - Added few words in commit message about why we do this change. - Appended a 2nd commit to the series for request DT bindings update.
Changes since v2: - Irq and per-cpu irq no more share the primary same handler function but have a common irq_handler() helper function. - Removed useless spinlocks. - Wrapped lines > 80 char.
Changes since v1: - Fixed missing __percpu attribute reported by kernel test robot. - Rephrased commit message and added Cc tags. --- drivers/tee/optee/optee_private.h | 24 ++++++ drivers/tee/optee/smc_abi.c | 122 +++++++++++++++++++++++++++++- 2 files changed, 142 insertions(+), 4 deletions(-)
diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h index 04ae58892608..6129d43dd354 100644 --- a/drivers/tee/optee/optee_private.h +++ b/drivers/tee/optee/optee_private.h @@ -94,11 +94,35 @@ struct optee_supp { struct completion reqs_c; };
+/* + * struct optee_pcpu - per cpu notif private struct passed to work functions + * @optee optee device reference + */ +struct optee_pcpu { + struct optee *optee; +}; + +/* + * struct optee_smc - optee smc communication struct + * @invoke_fn handler function to invoke secure monitor + * @memremaped_shm virtual address of memory in shared memory pool + * @sec_caps: secure world capabilities defined by + * OPTEE_SMC_SEC_CAP_* in optee_smc.h + * @notif_irq interrupt used as async notification by OP-TEE or 0 + * @optee_pcpu per_cpu optee instance for per cpu work or NULL + * @notif_pcpu_wq workqueue for per cpu aynchronous notification or NULL + * @notif_pcpu_work work for per cpu asynchronous notification + * @notif_cpuhp_state CPU hotplug state assigned for pcpu interrupt management + */ struct optee_smc { optee_invoke_fn *invoke_fn; void *memremaped_shm; u32 sec_caps; unsigned int notif_irq; + struct optee_pcpu __percpu *optee_pcpu; + struct workqueue_struct *notif_pcpu_wq; + struct work_struct notif_pcpu_work; + unsigned int notif_cpuhp_state; };
/** diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c index a1c1fa1a9c28..de7ac9a46354 100644 --- a/drivers/tee/optee/smc_abi.c +++ b/drivers/tee/optee/smc_abi.c @@ -52,6 +52,23 @@ */ #define OPTEE_MIN_STATIC_POOL_ALIGN 9 /* 512 bytes aligned */
+/* SMC ABI considers at most a single TEE firmware */ +static unsigned int pcpu_irq_num; + +static int optee_cpuhp_enable_pcpu_irq(unsigned int cpu) +{ + enable_percpu_irq(pcpu_irq_num, IRQ_TYPE_NONE); + + return 0; +} + +static int optee_cpuhp_disable_pcpu_irq(unsigned int cpu) +{ + disable_percpu_irq(pcpu_irq_num); + + return 0; +} + /* * 1. Convert between struct tee_param and struct optee_msg_param * @@ -991,9 +1008,8 @@ static u32 get_async_notif_value(optee_invoke_fn *invoke_fn, bool *value_valid, return res.a1; }
-static irqreturn_t notif_irq_handler(int irq, void *dev_id) +static irqreturn_t irq_handler(struct optee *optee) { - struct optee *optee = dev_id; bool do_bottom_half = false; bool value_valid; bool value_pending; @@ -1016,6 +1032,13 @@ static irqreturn_t notif_irq_handler(int irq, void *dev_id) return IRQ_HANDLED; }
+static irqreturn_t notif_irq_handler(int irq, void *dev_id) +{ + struct optee *optee = dev_id; + + return irq_handler(optee); +} + static irqreturn_t notif_irq_thread_fn(int irq, void *dev_id) { struct optee *optee = dev_id; @@ -1025,7 +1048,7 @@ static irqreturn_t notif_irq_thread_fn(int irq, void *dev_id) return IRQ_HANDLED; }
-static int optee_smc_notif_init_irq(struct optee *optee, u_int irq) +static int init_irq(struct optee *optee, u_int irq) { int rc;
@@ -1040,12 +1063,103 @@ static int optee_smc_notif_init_irq(struct optee *optee, u_int irq) return 0; }
+static irqreturn_t notif_pcpu_irq_handler(int irq, void *dev_id) +{ + struct optee_pcpu *pcpu = dev_id; + struct optee *optee = pcpu->optee; + + if (irq_handler(optee) == IRQ_WAKE_THREAD) + queue_work(optee->smc.notif_pcpu_wq, + &optee->smc.notif_pcpu_work); + + return IRQ_HANDLED; +} + +static void notif_pcpu_irq_work_fn(struct work_struct *work) +{ + struct optee_smc *optee_smc = container_of(work, struct optee_smc, + notif_pcpu_work); + struct optee *optee = container_of(optee_smc, struct optee, smc); + + optee_smc_do_bottom_half(optee->ctx); +} + +static int init_pcpu_irq(struct optee *optee, u_int irq) +{ + struct optee_pcpu __percpu *optee_pcpu; + int cpu, rc; + + optee_pcpu = alloc_percpu(struct optee_pcpu); + if (!optee_pcpu) + return -ENOMEM; + + for_each_present_cpu(cpu) + per_cpu_ptr(optee_pcpu, cpu)->optee = optee; + + rc = request_percpu_irq(irq, notif_pcpu_irq_handler, + "optee_pcpu_notification", optee_pcpu); + if (rc) + goto err_free_pcpu; + + INIT_WORK(&optee->smc.notif_pcpu_work, notif_pcpu_irq_work_fn); + optee->smc.notif_pcpu_wq = create_workqueue("optee_pcpu_notification"); + if (!optee->smc.notif_pcpu_wq) { + rc = -EINVAL; + goto err_free_pcpu_irq; + } + + optee->smc.optee_pcpu = optee_pcpu; + optee->smc.notif_irq = irq; + + pcpu_irq_num = irq; + rc = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "optee/pcpu-notif:starting", + optee_cpuhp_enable_pcpu_irq, + optee_cpuhp_disable_pcpu_irq); + if (!rc) + rc = -EINVAL; + if (rc < 0) + goto err_free_pcpu_irq; + + optee->smc.notif_cpuhp_state = rc; + + return 0; + +err_free_pcpu_irq: + free_percpu_irq(irq, optee_pcpu); +err_free_pcpu: + free_percpu(optee_pcpu); + + return rc; +} + +static int optee_smc_notif_init_irq(struct optee *optee, u_int irq) +{ + if (irq_is_percpu_devid(irq)) + return init_pcpu_irq(optee, irq); + else + return init_irq(optee, irq); +} + +static void uninit_pcpu_irq(struct optee *optee) +{ + cpuhp_remove_state(optee->smc.notif_cpuhp_state); + + destroy_workqueue(optee->smc.notif_pcpu_wq); + + free_percpu_irq(optee->smc.notif_irq, optee->smc.optee_pcpu); + free_percpu(optee->smc.optee_pcpu); +} + 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); if (optee->smc.notif_irq) { - free_irq(optee->smc.notif_irq, optee); + if (irq_is_percpu_devid(optee->smc.notif_irq)) + uninit_pcpu_irq(optee); + else + free_irq(optee->smc.notif_irq, optee); + irq_dispose_mapping(optee->smc.notif_irq); } }