[PATCH 3/3] optee core: add irq chip using optee async notification
From: Etienne Carriere
Date: Thu Jan 12 2023 - 10:08:05 EST
Adds an irq chip in optee driver to generate interrupts from OP-TEE
notified interrupt events based on optee async notification. Upon such
notification, optee driver invokes OP-TEE to query a pending interrupt
event. If an interrupt notification is pending the invocation return
OPTEE_SMC_ASYNC_NOTIF_VALUE_DO_IT and optee driver can get the pending
interrupt number with SMC function ID OPTEE_SMC_FUNCID_GET_IT_VALUE.
SMC function ID OPTEE_SMC_FUNCID_SET_IT_MASK allows Linux to mask/unmask
an interrupt notification services.
The optee irq_chip if flagged IRQCHIP_SKIP_SET_WAKE to skip set_wake
as optee interrupt notifications doesn't support the set_wake option.
In case a device is using the optee irq and is marked as wakeup source,
this result in an "Unbalanced IRQ xx wake disable" backtrace, since:
- in irq_set_irq_wake(ON), wake_depth gets incremented, then reset due to
set_irq_wake_real() returns an error (irq_set_wake() isn't implemented)
- in irq_set_irq_wake(OFF), wake_depth is always 0, hence the warning
Co-developed-by: Pascal Paillet <p.paillet@xxxxxxxxxxx>
Signed-off-by: Pascal Paillet <p.paillet@xxxxxxxxxxx>
Co-developed-by: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx>
Signed-off-by: Etienne Carriere <etienne.carriere@xxxxxxxxxx>
---
drivers/tee/optee/optee_private.h | 2 +
drivers/tee/optee/optee_smc.h | 78 +++++++++++++++-
drivers/tee/optee/smc_abi.c | 142 ++++++++++++++++++++++++++++--
3 files changed, 216 insertions(+), 6 deletions(-)
diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
index e5bd3548691f..2a146d884d27 100644
--- a/drivers/tee/optee/optee_private.h
+++ b/drivers/tee/optee/optee_private.h
@@ -112,6 +112,7 @@ struct optee_pcpu {
* @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
+ * @domain interrupt domain registered by OP-TEE driver
*/
struct optee_smc {
optee_invoke_fn *invoke_fn;
@@ -121,6 +122,7 @@ struct optee_smc {
struct optee_pcpu __percpu *optee_pcpu;
struct workqueue_struct *notif_pcpu_wq;
struct work_struct notif_pcpu_work;
+ struct irq_domain *domain;
};
/**
diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h
index 73b5e7760d10..0cf83d5a2931 100644
--- a/drivers/tee/optee/optee_smc.h
+++ b/drivers/tee/optee/optee_smc.h
@@ -226,7 +226,8 @@ struct optee_smc_get_shm_config_result {
* a3 Bit[7:0]: Number of parameters needed for RPC to be supplied
* as the second MSG arg struct for
* OPTEE_SMC_CALL_WITH_ARG
- * Bit[31:8]: Reserved (MBZ)
+ * Bit[23:8]: The maximum interrupt event notification number
+ * Bit[31:24]: Reserved (MBZ)
* a4-7 Preserved
*
* Error return register usage:
@@ -254,6 +255,11 @@ struct optee_smc_get_shm_config_result {
#define OPTEE_SMC_SEC_CAP_ASYNC_NOTIF BIT(5)
/* Secure world supports pre-allocating RPC arg struct */
#define OPTEE_SMC_SEC_CAP_RPC_ARG BIT(6)
+/* Secure world supports interrupt events notification to normal world */
+#define OPTEE_SMC_SEC_CAP_IT_NOTIF BIT(7)
+
+#define OPTEE_SMC_SEC_CAP_MAX_NOTIF_IT_MASK GENMASK(23, 8)
+#define OPTEE_SMC_SEC_CAP_MAX_NOTIF_IT_SHIFT 8
#define OPTEE_SMC_FUNCID_EXCHANGE_CAPABILITIES 9
#define OPTEE_SMC_EXCHANGE_CAPABILITIES \
@@ -416,6 +422,12 @@ struct optee_smc_disable_shm_cache_result {
*/
#define OPTEE_SMC_ASYNC_NOTIF_VALUE_DO_BOTTOM_HALF 0
+/*
+ * Notification that OP-TEE triggers an interrupt event to Linux kernel
+ * for an interrupt consumer.
+ */
+#define OPTEE_SMC_ASYNC_NOTIF_VALUE_DO_IT 1
+
#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)
@@ -426,6 +438,70 @@ struct optee_smc_disable_shm_cache_result {
/* See OPTEE_SMC_CALL_WITH_REGD_ARG above */
#define OPTEE_SMC_FUNCID_CALL_WITH_REGD_ARG 19
+/*
+ * Retrieve the interrupt number of the pending interrupt event notified to
+ * non-secure world since the last call of this function.
+ *
+ * OP-TEE keeps a record of all posted interrupt notification events. When the
+ * async notif interrupt is received by non-secure world, this function should
+ * be called until all pended interrupt events have been retrieved. When an
+ * interrupt event is retrieved it is cleared from the record in secure world.
+ *
+ * It is expected that this function is called from an interrupt handler
+ * in normal world.
+ *
+ * Call requests usage:
+ * a0 SMC Function ID, OPTEE_SMC_GET_IT_NOTIF_VALUE
+ * a1-6 Not used
+ * a7 Hypervisor Client ID register
+ *
+ * Normal return register usage:
+ * a0 OPTEE_SMC_RETURN_OK
+ * a1 IT_NOTIF interrupt identifier value
+ * a2 Bit[0]: OPTEE_SMC_IT_NOTIF_VALID if the value in a1 is
+ * valid, else 0 if no interrupt event were pending
+ * a2 Bit[1]: OPTEE_SMC_IT_NOTIF_PENDING if another interrupt event
+ * 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_IT_NOTIF_VALID BIT(0)
+#define OPTEE_SMC_IT_NOTIF_PENDING BIT(1)
+
+#define OPTEE_SMC_FUNCID_GET_IT_NOTIF_VALUE 20
+#define OPTEE_SMC_GET_IT_NOTIF_VALUE \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_GET_IT_NOTIF_VALUE)
+
+/*
+ * Mask or unmask an interrupt notification event.
+ *
+ * It is expected that this function is called from an interrupt handler
+ * in normal world.
+ *
+ * Call requests usage:
+ * a0 SMC Function ID, OPTEE_SMC_SET_IT_NOTIF_MASK
+ * a1 Interrupt identifier value
+ * a2 Bit[0]: 1 if interrupt event is to be masked, 0 if it is to be unmasked
+ * a2 Bit[31:1] MBZ
+ * a3-6 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_SET_IT_NOTIF_MASK 21
+#define OPTEE_SMC_SET_IT_NOTIF_MASK \
+ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_SET_IT_NOTIF_MASK)
+
/*
* Resume from RPC (for example after processing a foreign interrupt)
*
diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
index 8c2d58d605ac..0360afde119f 100644
--- a/drivers/tee/optee/smc_abi.c
+++ b/drivers/tee/optee/smc_abi.c
@@ -977,6 +977,112 @@ static int optee_smc_stop_async_notif(struct tee_context *ctx)
* 5. Asynchronous notification
*/
+static u32 get_it_value(optee_invoke_fn *invoke_fn, bool *value_valid,
+ bool *value_pending)
+{
+ struct arm_smccc_res res;
+
+ invoke_fn(OPTEE_SMC_GET_IT_NOTIF_VALUE, 0, 0, 0, 0, 0, 0, 0, &res);
+
+ if (res.a0)
+ return 0;
+
+ *value_valid = res.a2 & OPTEE_SMC_IT_NOTIF_VALID;
+ *value_pending = res.a2 & OPTEE_SMC_IT_NOTIF_PENDING;
+ return res.a1;
+}
+
+static u32 set_it_mask(optee_invoke_fn *invoke_fn, u32 it_value, bool mask)
+{
+ struct arm_smccc_res res;
+
+ invoke_fn(OPTEE_SMC_SET_IT_NOTIF_MASK, it_value, mask, 0, 0, 0, 0, 0, &res);
+
+ if (res.a0)
+ return 0;
+
+ return res.a1;
+}
+
+static int handle_optee_it(struct optee *optee)
+{
+ bool value_valid;
+ bool value_pending;
+ u32 it;
+
+ do {
+ struct irq_desc *desc;
+
+ it = get_it_value(optee->smc.invoke_fn, &value_valid, &value_pending);
+ if (!value_valid)
+ break;
+
+ desc = irq_to_desc(irq_find_mapping(optee->smc.domain, it));
+ if (!desc) {
+ pr_err("no desc for optee IT:%d\n", it);
+ return -EIO;
+ }
+
+ handle_simple_irq(desc);
+
+ } while (value_pending);
+
+ return 0;
+}
+
+static void optee_it_irq_mask(struct irq_data *d)
+{
+ struct optee *optee = d->domain->host_data;
+
+ set_it_mask(optee->smc.invoke_fn, d->hwirq, true);
+}
+
+static void optee_it_irq_unmask(struct irq_data *d)
+{
+ struct optee *optee = d->domain->host_data;
+
+ set_it_mask(optee->smc.invoke_fn, d->hwirq, false);
+}
+
+static struct irq_chip optee_it_irq_chip = {
+ .name = "optee-it",
+ .irq_disable = optee_it_irq_mask,
+ .irq_enable = optee_it_irq_unmask,
+ .flags = IRQCHIP_SKIP_SET_WAKE,
+};
+
+static int optee_it_alloc(struct irq_domain *d, unsigned int virq,
+ unsigned int nr_irqs, void *data)
+{
+ struct irq_fwspec *fwspec = data;
+ irq_hw_number_t hwirq;
+
+ hwirq = fwspec->param[0];
+
+ irq_domain_set_hwirq_and_chip(d, virq, hwirq, &optee_it_irq_chip, d->host_data);
+
+ return 0;
+}
+
+static const struct irq_domain_ops optee_it_irq_domain_ops = {
+ .alloc = optee_it_alloc,
+ .free = irq_domain_free_irqs_common,
+};
+
+static int optee_irq_domain_init(struct platform_device *pdev, struct optee *optee, u_int max_it)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+
+ optee->smc.domain = irq_domain_add_linear(np, max_it, &optee_it_irq_domain_ops, optee);
+ if (!optee->smc.domain) {
+ dev_err(dev, "Unable to add irq domain\n");
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
static u32 get_async_notif_value(optee_invoke_fn *invoke_fn, bool *value_valid,
bool *value_pending)
{
@@ -1008,13 +1114,15 @@ static irqreturn_t notif_irq_handler(int irq, void *dev_id)
}
do {
- value = get_async_notif_value(optee->smc.invoke_fn,
- &value_valid, &value_pending);
+ 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 if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_IT_NOTIF &&
+ value == OPTEE_SMC_ASYNC_NOTIF_VALUE_DO_IT)
+ handle_optee_it(optee);
else
optee_notif_send(optee, value);
} while (value_pending);
@@ -1042,8 +1150,7 @@ static int init_irq(struct optee *optee, u_int irq)
{
int rc;
- rc = request_threaded_irq(irq, notif_irq_handler,
- notif_irq_thread_fn,
+ rc = request_threaded_irq(irq, notif_irq_handler, notif_irq_thread_fn,
0, "optee_notification", optee);
if (rc)
return rc;
@@ -1145,6 +1252,9 @@ static void optee_smc_notif_uninit_irq(struct optee *optee)
irq_dispose_mapping(optee->smc.notif_irq);
}
+
+ if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_IT_NOTIF)
+ irq_domain_remove(optee->smc.domain);
}
}
@@ -1284,6 +1394,7 @@ 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 *max_notif_value,
+ u32 *max_notif_it,
unsigned int *rpc_param_count)
{
union {
@@ -1316,6 +1427,12 @@ static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
else
*rpc_param_count = 0;
+ if (*sec_caps & OPTEE_SMC_SEC_CAP_IT_NOTIF)
+ *max_notif_it = (res.result.data & OPTEE_SMC_SEC_CAP_MAX_NOTIF_IT_MASK) >>
+ OPTEE_SMC_SEC_CAP_MAX_NOTIF_IT_SHIFT;
+ else
+ *max_notif_it = 0;
+
return true;
}
@@ -1461,6 +1578,7 @@ static int optee_probe(struct platform_device *pdev)
struct tee_device *teedev;
struct tee_context *ctx;
u32 max_notif_value;
+ u32 max_notif_it;
u32 arg_cache_flags;
u32 sec_caps;
int rc;
@@ -1482,7 +1600,7 @@ static int optee_probe(struct platform_device *pdev)
}
if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps,
- &max_notif_value,
+ &max_notif_value, &max_notif_it,
&rpc_param_count)) {
pr_warn("capabilities mismatch\n");
return -EINVAL;
@@ -1603,6 +1721,20 @@ static int optee_probe(struct platform_device *pdev)
irq_dispose_mapping(irq);
goto err_notif_uninit;
}
+
+ if (sec_caps & OPTEE_SMC_SEC_CAP_IT_NOTIF) {
+ rc = optee_irq_domain_init(pdev, optee, max_notif_it);
+ if (rc) {
+ if (irq_is_percpu_devid(optee->smc.notif_irq))
+ uninit_pcpu_irq(optee);
+ else
+ free_irq(optee->smc.notif_irq, optee);
+
+ irq_dispose_mapping(irq);
+ goto err_notif_uninit;
+ }
+ }
+
enable_async_notif(optee->smc.invoke_fn);
pr_info("Asynchronous notifications enabled\n");
}
--
2.25.1