From:   Etienne Carriere <etienne.carriere@linaro.org>
To:     linux-kernel@vger.kernel.org
Cc:     linux-arm-kernel@lists.infradead.org,
        Etienne Carriere <etienne.carriere@linaro.org>,
        Jens Wiklander <jens.wiklander@linaro.org>,
        Marc Zyngier <maz@kernel.org>,
        Sumit Garg <sumit.garg@linaro.org>
Subject: [PATCH v3 3/3] optee: add enable/disable/set_wake handlers to optee irqs
Date:   Wed, 15 Mar 2023 12:32:01 +0100
Message-Id: <20230315113201.1343781-3-etienne.carriere@linaro.org>
In-Reply-To: <20230315113201.1343781-1-etienne.carriere@linaro.org>
References: <20230315113201.1343781-1-etienne.carriere@linaro.org>
MIME-Version: 1.0
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Precedence: bulk

Implements OP-TEE's It Notif PTA API to deactivate and activate an
interrupt notifier and to configure the wakeup capability
of that interrupt. These controls are useful for efficient power
management of the device when an interrupt controller resources is
hosted in OP-TEE world.

When OP-TEE does not implement the It Notif PTA, the related handlers
simply return with success. If OP-TEE exposes the PTA services, they
are invoked on enable, disable and set_wake irqchip operations.

Cc: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Sumit Garg <sumit.garg@linaro.org>

Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
---
Changes since v3:
- Renamed it_notif/IT_NOTIF to itr_notif/ITR_NOTIF.

Changes since v2:
- Patch added in v2 series for power-up/down and wakeup configuration
  of the irq chip.

Patch not present in v1
- Patch added for power-up/down and wakeup configuration of the irq chip.
---
 drivers/tee/optee/optee_private.h |   2 +
 drivers/tee/optee/smc_abi.c       | 157 ++++++++++++++++++++++++++++++
 2 files changed, 159 insertions(+)

diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
index f467409e02e9..4b4002d81315 100644
--- a/drivers/tee/optee/optee_private.h
+++ b/drivers/tee/optee/optee_private.h
@@ -166,6 +166,7 @@ struct optee_ops {
  * @scan_bus_done	flag if device registation was already done.
  * @scan_bus_wq		workqueue to scan optee bus and register optee drivers
  * @scan_bus_work	workq to scan optee bus and register optee drivers
+ * @notif_itr_pta_ctx   TEE context for invoking interrupt configuration services
  */
 struct optee {
 	struct tee_device *supp_teedev;
@@ -185,6 +186,7 @@ struct optee {
 	bool   scan_bus_done;
 	struct workqueue_struct *scan_bus_wq;
 	struct work_struct scan_bus_work;
+	struct tee_context *notif_itr_pta_ctx;
 };
 
 struct optee_session {
diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
index 6e6c6979abfd..046aa242b2ef 100644
--- a/drivers/tee/optee/smc_abi.c
+++ b/drivers/tee/optee/smc_abi.c
@@ -52,6 +52,43 @@
  */
 #define OPTEE_MIN_STATIC_POOL_ALIGN    9 /* 512 bytes aligned */
 
+/*
+ * Interrupt notification can be configured using Notif-IT PTA services.
+ * Below are the PTA UUID and its API commands.
+ */
+#define PTA_ITR_NOTIF_UUID \
+	UUID_INIT(0x4461e5c7, 0xb523, 0x4b73, 0xac, 0xed, 0x75, 0xad, \
+		  0x2b, 0x9b, 0x59, 0xa1)
+
+/*
+ * PTA_ITR_NOTIF_ACTIVATE_DETECTION - Enable a interrupt notification
+ *
+ * [in]  params[0].value.a     Interrupt ID
+ */
+#define PTA_ITR_NOTIF_ACTIVATE_DETECTION	0
+
+/*
+ * PTA_ITR_NOTIF_DEACTIVATE_DETECTION - Disable a interrupt notification
+ *
+ * [in]  params[0].value.a     Interrupt ID
+ */
+#define PTA_ITR_NOTIF_DEACTIVATE_DETECTION	1
+
+/*
+ * PTA_ITR_NOTIF_ENABLE_WAKEUP_SOURCE - Enable an interrupt wakeup source
+ *
+ * [in]  params[0].value.a     Interrupt ID
+ */
+#define PTA_ITR_NOTIF_ENABLE_WAKEUP_SOURCE	2
+
+/*
+ * PTA_ITR_NOTIF_ENABLE_WAKEUP_SOURCE - Disable an interrupt wakeup source
+ *
+ * [in]  params[0].value.a     Interrupt ID
+ */
+#define PTA_ITR_NOTIF_DISABLE_WAKEUP_SOURCE	3
+
+
 /*
  * 1. Convert between struct tee_param and struct optee_msg_param
  *
@@ -977,6 +1014,92 @@ static int optee_smc_stop_async_notif(struct tee_context *ctx)
  * 5. Asynchronous notification
  */
 
+static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
+{
+	return ver->impl_id == TEE_IMPL_ID_OPTEE;
+}
+
+static void init_optee_pta_context(struct optee *optee)
+{
+	struct tee_context *ctx = NULL;
+	const uuid_t pta_uuid = PTA_ITR_NOTIF_UUID;
+	struct tee_ioctl_open_session_arg sess_arg;
+	int ret;
+
+	ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, NULL);
+	if (IS_ERR(ctx))
+		return;
+
+	memset(&sess_arg, 0, sizeof(sess_arg));
+	export_uuid(sess_arg.uuid, &pta_uuid);
+	sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
+
+	ret = tee_client_open_session(ctx, &sess_arg, NULL);
+	if ((ret < 0) || (sess_arg.ret != 0)) {
+		pr_err("Can't open ITR_NOTIF PTA session: %#x\n", sess_arg.ret);
+		tee_client_close_context(ctx);
+		return;
+	}
+
+	tee_client_close_session(ctx, sess_arg.session);
+
+	optee->notif_itr_pta_ctx = ctx;
+}
+
+static void release_optee_pta_context(struct optee *optee)
+{
+	if (optee->notif_itr_pta_ctx) {
+		tee_client_close_context(optee->notif_itr_pta_ctx);
+		optee->notif_itr_pta_ctx = NULL;
+	}
+}
+
+static int invoke_optee_pta(struct optee *optee, unsigned int command,
+			    unsigned int irq_id)
+{
+	const uuid_t pta_uuid = PTA_ITR_NOTIF_UUID;
+	struct tee_ioctl_open_session_arg sess_arg;
+	struct tee_ioctl_invoke_arg inv_arg;
+	struct tee_param param[1];
+	int ret;
+
+	if (!optee->notif_itr_pta_ctx)
+		return -ENOENT;
+
+	memset(&sess_arg, 0, sizeof(sess_arg));
+	export_uuid(sess_arg.uuid, &pta_uuid);
+	sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
+
+	ret = tee_client_open_session(optee->notif_itr_pta_ctx, &sess_arg, NULL);
+	if ((ret < 0) || (sess_arg.ret != 0)) {
+		pr_err("tee_client_open_session failed, err: %#x\n", sess_arg.ret);
+		if (!ret)
+			ret = -EINVAL;
+		return ret;
+	}
+
+	memset(&inv_arg, 0, sizeof(inv_arg));
+	inv_arg.session = sess_arg.session;
+	inv_arg.func = command;
+	inv_arg.num_params = 1;
+
+	memset(&param, 0, sizeof(param));
+	param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
+	param[0].u.value.a = irq_id;
+
+	ret = tee_client_invoke_func(optee->notif_itr_pta_ctx, &inv_arg, param);
+	if ((ret < 0) || (inv_arg.ret != 0)) {
+		pr_err("tee_client_invoke_func failed, ret: %d, err: %#x\n",
+		       ret, inv_arg.ret);
+		if (!ret)
+			ret = -EINVAL;
+	}
+
+	tee_client_close_session(optee->notif_itr_pta_ctx, sess_arg.session);
+
+	return ret;
+}
+
 static void optee_itr_notif_mask(struct irq_data *d)
 {
 	struct optee *optee = d->domain->host_data;
@@ -995,10 +1118,40 @@ static void optee_itr_notif_unmask(struct irq_data *d)
 			     0, 0, 0, 0, 0, &res);
 }
 
+static void optee_itr_notif_disable(struct irq_data *d)
+{
+	struct optee *optee = d->domain->host_data;
+
+	(void)invoke_optee_pta(optee, PTA_ITR_NOTIF_DEACTIVATE_DETECTION, d->hwirq);
+}
+
+static void optee_itr_notif_enable(struct irq_data *d)
+{
+	struct optee *optee = d->domain->host_data;
+
+	(void)invoke_optee_pta(optee, PTA_ITR_NOTIF_ACTIVATE_DETECTION, d->hwirq);
+}
+
+static int optee_itr_notif_set_wake(struct irq_data *d, unsigned int on)
+{
+	struct optee *optee = d->domain->host_data;
+	u32 command;
+
+	if (on)
+		command = PTA_ITR_NOTIF_ENABLE_WAKEUP_SOURCE;
+	else
+		command = PTA_ITR_NOTIF_DISABLE_WAKEUP_SOURCE;
+
+	return invoke_optee_pta(optee, command, d->hwirq);
+}
+
 static struct irq_chip optee_irq_chip = {
 	.name = "optee-it",
 	.irq_mask = optee_itr_notif_mask,
 	.irq_unmask = optee_itr_notif_unmask,
+	.irq_disable = optee_itr_notif_disable,
+	.irq_enable = optee_itr_notif_enable,
+	.irq_set_wake = optee_itr_notif_set_wake,
 };
 
 static int optee_itr_alloc(struct irq_domain *d, unsigned int virq,
@@ -1459,6 +1612,7 @@ static int optee_smc_remove(struct platform_device *pdev)
 		optee_disable_shm_cache(optee);
 
 	optee_smc_notif_uninit_irq(optee);
+	release_optee_pta_context(optee);
 
 	optee_remove_common(optee);
 
@@ -1646,6 +1800,8 @@ static int optee_probe(struct platform_device *pdev)
 				irq_dispose_mapping(irq);
 				goto err_notif_uninit;
 			}
+
+			init_optee_pta_context(optee);
 		}
 
 		enable_async_notif(optee->smc.invoke_fn);
@@ -1683,6 +1839,7 @@ static int optee_probe(struct platform_device *pdev)
 		optee_disable_shm_cache(optee);
 	optee_smc_notif_uninit_irq(optee);
 	optee_unregister_devices();
+	release_optee_pta_context(optee);
 err_notif_uninit:
 	optee_notif_uninit(optee);
 err_close_ctx:
-- 
2.25.1