Commit b3b4ced1 authored by Etienne Carriere's avatar Etienne Carriere Committed by Jens Wiklander
Browse files

optee: add per cpu asynchronous notification 



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: default avatarAlexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: default avatarAlexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: default avatarEtienne Carriere <etienne.carriere@linaro.org>
Reviewed-by: default avatarSumit Garg <sumit.garg@linaro.org>
[JW: fixing a spell error in @notif_pcpu_wq description]
Signed-off-by: default avatarJens Wiklander <jens.wiklander@linaro.org>
parent 0d0eaa78

drivers/tee/optee/optee_private.h

+24 −0
Original line number Diff line number Diff line
@@ -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 asynchronous 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;

};



/**

drivers/tee/optee/smc_abi.c

+118 −4
Original line number Diff line number Diff line
@@ -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) {

			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);

		}

	}