Unverified Commit 87dcb2f0 authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

Merge tag 'ffa-updates-6.11' of... 

Merge tag 'ffa-updates-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into soc/drivers

Arm FF-A driver updates for  v6.11

The main addition is the split of bus and driver into distinct modules
The FF-A bus module is initialized at subsys_initcall level when builtin.

FF-A drivers initialization is now changed to module_init level so that
pKVM ffa proxy is all setup and running in case pKVM hypervisor needs to
trap and handle FF-A calls.

One of the reason for not having this split from the beginning is the
need to workaround the FF-A v1.0 NULL UUID. The FF-A bus layer called
into FF-A driver and populated the device UUID if it matches with the
driver attempting to match. Moving the workaround away from the FF-A
bus layer to the FF-A core driver as a bus notifier will help to remove
the dependency.

* tag 'ffa-updates-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
  firmware: arm_ffa: Split bus and driver into distinct modules
  firmware: arm_ffa: Move the FF-A v1.0 NULL UUID workaround to bus notifier

Link: https://lore.kernel.org/r/20240624103451.2870146-1-sudeep.holla@arm.com


Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parents 7cab811d 18c250bd

drivers/firmware/arm_ffa/Makefile

+4 −2
Original line number Diff line number Diff line
@@ -2,5 +2,7 @@ 
ffa-bus-y = bus.o

ffa-driver-y = driver.o

ffa-transport-$(CONFIG_ARM_FFA_SMCCC) += smccc.o

ffa-module-objs := $(ffa-bus-y) $(ffa-driver-y) $(ffa-transport-y)

obj-$(CONFIG_ARM_FFA_TRANSPORT) = ffa-module.o
 
ffa-core-objs := $(ffa-bus-y)

ffa-module-objs := $(ffa-driver-y) $(ffa-transport-y)

obj-$(CONFIG_ARM_FFA_TRANSPORT)  = ffa-core.o

obj-$(CONFIG_ARM_FFA_TRANSPORT) += ffa-module.o

drivers/firmware/arm_ffa/bus.c

+16 −6
Original line number Diff line number Diff line
@@ -30,12 +30,11 @@ static int ffa_device_match(struct device *dev, struct device_driver *drv) 
	while (!uuid_is_null(&id_table->uuid)) {

		/*

		 * FF-A v1.0 doesn't provide discovery of UUIDs, just the

		 * partition IDs, so fetch the partitions IDs for this

		 * id_table UUID and assign the UUID to the device if the

		 * partition ID matches

		 * partition IDs, so match it unconditionally here and handle

		 * it via the installed bus notifier during driver binding.

		 */

		if (uuid_is_null(&ffa_dev->uuid))

			ffa_device_match_uuid(ffa_dev, &id_table->uuid);

			return 1;



		if (uuid_equal(&ffa_dev->uuid, &id_table->uuid))

			return 1;
@@ -50,6 +49,10 @@ static int ffa_device_probe(struct device *dev) 
	struct ffa_driver *ffa_drv = to_ffa_driver(dev->driver);

	struct ffa_device *ffa_dev = to_ffa_dev(dev);



	/* UUID can be still NULL with FF-A v1.0, so just skip probing them */

	if (uuid_is_null(&ffa_dev->uuid))

		return -ENODEV;



	return ffa_drv->probe(ffa_dev);

}
@@ -232,14 +235,21 @@ void ffa_device_unregister(struct ffa_device *ffa_dev) 
}

EXPORT_SYMBOL_GPL(ffa_device_unregister);



int arm_ffa_bus_init(void)

static int __init arm_ffa_bus_init(void)

{

	return bus_register(&ffa_bus_type);

}

subsys_initcall(arm_ffa_bus_init);



void arm_ffa_bus_exit(void)

static void __exit arm_ffa_bus_exit(void)

{

	ffa_devices_unregister();

	bus_unregister(&ffa_bus_type);

	ida_destroy(&ffa_bus_id);

}

module_exit(arm_ffa_bus_exit);



MODULE_ALIAS("ffa-core");

MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");

MODULE_DESCRIPTION("ARM FF-A bus");

MODULE_LICENSE("GPL");

drivers/firmware/arm_ffa/common.h

+0 −2
Original line number Diff line number Diff line
@@ -14,8 +14,6 @@ typedef struct arm_smccc_1_2_regs ffa_value_t; 


typedef void (ffa_fn)(ffa_value_t, ffa_value_t *);



int arm_ffa_bus_init(void);

void arm_ffa_bus_exit(void);

bool ffa_device_is_valid(struct ffa_device *ffa_dev);

void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid);

drivers/firmware/arm_ffa/driver.c

+38 −19
Original line number Diff line number Diff line
@@ -1224,14 +1224,6 @@ void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid) 
	int count, idx;

	struct ffa_partition_info *pbuf, *tpbuf;



	/*

	 * FF-A v1.1 provides UUID for each partition as part of the discovery

	 * API, the discovered UUID must be populated in the device's UUID and

	 * there is no need to copy the same from the driver table.

	 */

	if (drv_info->version > FFA_VERSION_1_0)

		return;



	count = ffa_partition_probe(uuid, &pbuf);

	if (count <= 0)

		return;
@@ -1242,6 +1234,35 @@ void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid) 
	kfree(pbuf);

}



static int

ffa_bus_notifier(struct notifier_block *nb, unsigned long action, void *data)

{

	struct device *dev = data;

	struct ffa_device *fdev = to_ffa_dev(dev);



	if (action == BUS_NOTIFY_BIND_DRIVER) {

		struct ffa_driver *ffa_drv = to_ffa_driver(dev->driver);

		const struct ffa_device_id *id_table= ffa_drv->id_table;



		/*

		 * FF-A v1.1 provides UUID for each partition as part of the

		 * discovery API, the discovered UUID must be populated in the

		 * device's UUID and there is no need to workaround by copying

		 * the same from the driver table.

		 */

		if (uuid_is_null(&fdev->uuid))

			ffa_device_match_uuid(fdev, &id_table->uuid);



		return NOTIFY_OK;

	}



	return NOTIFY_DONE;

}



static struct notifier_block ffa_bus_nb = {

	.notifier_call = ffa_bus_notifier,

};



static int ffa_setup_partitions(void)

{

	int count, idx, ret;
@@ -1250,6 +1271,12 @@ static int ffa_setup_partitions(void) 
	struct ffa_dev_part_info *info;

	struct ffa_partition_info *pbuf, *tpbuf;



	if (drv_info->version == FFA_VERSION_1_0) {

		ret = bus_register_notifier(&ffa_bus_type, &ffa_bus_nb);

		if (ret)

			pr_err("Failed to register FF-A bus notifiers\n");

	}



	count = ffa_partition_probe(&uuid_null, &pbuf);

	if (count <= 0) {

		pr_info("%s: No partitions found, error %d\n", __func__, count);
@@ -1261,7 +1288,7 @@ static int ffa_setup_partitions(void) 
		import_uuid(&uuid, (u8 *)tpbuf->uuid);



		/* Note that if the UUID will be uuid_null, that will require

		 * ffa_device_match() to find the UUID of this partition id

		 * ffa_bus_notifier() to find the UUID of this partition id

		 * with help of ffa_device_match_uuid(). FF-A v1.1 and above

		 * provides UUID here for each partition as part of the

		 * discovery API and the same is passed.
@@ -1581,14 +1608,9 @@ static int __init ffa_init(void) 
	if (ret)

		return ret;



	ret = arm_ffa_bus_init();

	if (ret)

		return ret;



	drv_info = kzalloc(sizeof(*drv_info), GFP_KERNEL);

	if (!drv_info) {

		ret = -ENOMEM;

		goto ffa_bus_exit;

		return -ENOMEM;

	}



	ret = ffa_version_check(&drv_info->version);
@@ -1649,11 +1671,9 @@ static int __init ffa_init(void) 
	free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);

free_drv_info:

	kfree(drv_info);

ffa_bus_exit:

	arm_ffa_bus_exit();

	return ret;

}

subsys_initcall(ffa_init);

module_init(ffa_init);



static void __exit ffa_exit(void)

{
@@ -1663,7 +1683,6 @@ static void __exit ffa_exit(void) 
	free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE);

	free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE);

	kfree(drv_info);

	arm_ffa_bus_exit();

}

module_exit(ffa_exit);