[PATCH v2] firmware: arm_ffa: Stash the partition properties for query purposes

Sudeep Holla sudeep.holla at arm.com
Wed Apr 17 02:09:21 PDT 2024


The properies obtained from the partition information descriptor as
part of initial partitions discovery is useful as it contain info
if the partition
- Runs in AArch64 or AArch32 execution state
- Can send and/or receive direct requests
- Can send and receive indirect message
- Does support receipt of notifications.

These can be used for querying before attempting to do any of the
above operations.

Signed-off-by: Sudeep Holla <sudeep.holla at arm.com>
---
 drivers/firmware/arm_ffa/driver.c |  2 ++
 include/linux/arm_ffa.h           | 17 +++++++++++++++++
 2 files changed, 19 insertions(+)

Changes in v2:
 - Made this independent/standalone patch
 - Moved properties to struct ffa_device
 - Added accessors for the ffa_drivers to use if they prefer to check
   certain properties
 - Dropped the check in the core ffa driver as it could be expensive to
   do such checks each time, now deferred to FFA drivers
 - Link to v1: https://lore.kernel.org/linux-arm-kernel/20240415-ffa_msg2_support-v1-1-a28c964b1b3f@arm.com/

diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
index 9bc2e10381af..7dfc20186496 100644
--- a/drivers/firmware/arm_ffa/driver.c
+++ b/drivers/firmware/arm_ffa/driver.c
@@ -1227,6 +1227,8 @@ static int ffa_setup_partitions(void)
 			continue;
 		}

+		ffa_dev->properties = tpbuf->properties;
+
 		if (drv_info->version > FFA_VERSION_1_0 &&
 		    !(tpbuf->properties & FFA_PARTITION_AARCH64_EXEC))
 			ffa_mode_32bit_set(ffa_dev);
diff --git a/include/linux/arm_ffa.h b/include/linux/arm_ffa.h
index c906f666ff5d..b8f10a0a89fa 100644
--- a/include/linux/arm_ffa.h
+++ b/include/linux/arm_ffa.h
@@ -126,6 +126,7 @@
 /* FFA Bus/Device/Driver related */
 struct ffa_device {
 	u32 id;
+	u32 properties;
 	int vm_id;
 	bool mode_32bit;
 	uuid_t uuid;
@@ -221,12 +222,28 @@ struct ffa_partition_info {
 #define FFA_PARTITION_DIRECT_SEND	BIT(1)
 /* partition can send and receive indirect messages. */
 #define FFA_PARTITION_INDIRECT_MSG	BIT(2)
+/* partition can receive notifications */
+#define FFA_PARTITION_NOTIFICATION_RECV	BIT(3)
 /* partition runs in the AArch64 execution state. */
 #define FFA_PARTITION_AARCH64_EXEC	BIT(8)
 	u32 properties;
 	u32 uuid[4];
 };

+static bool ffa_partition_check_property(struct ffa_device *dev, u32 property)
+{
+	return dev->properties & property;
+}
+
+#define ffa_partition_supports_notify_recv(dev)	\
+	ffa_partition_check_property(dev, FFA_PARTITION_NOTIFICATION_RECV)
+
+#define ffa_partition_supports_indirect_msg(dev)	\
+	ffa_partition_check_property(dev, FFA_PARTITION_INDIRECT_MSG)
+
+#define ffa_partition_supports_direct_recv(dev)	\
+	ffa_partition_check_property(dev, FFA_PARTITION_DIRECT_RECV)
+
 /* For use with FFA_MSG_SEND_DIRECT_{REQ,RESP} which pass data via registers */
 struct ffa_send_direct_data {
 	unsigned long data0; /* w3/x3 */
--
2.43.2




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