firmware: arm_ffa: Don't set the memory region attributes for MEM_LEND

As per the FF-A specification: section "Usage of other memory region
attributes", in a transaction to donate memory or lend memory to a single
borrower, if the receiver is a PE or Proxy endpoint, the owner must not
specify the attributes and the relayer will return INVALID_PARAMETERS
if the attributes are set.

Let us not set the memory region attributes for MEM_LEND.

Fixes: 82a8daa ("firmware: arm_ffa: Add support for MEM_LEND")
Reported-by: Joao Alves <joao.alves@arm.com>
Reported-by: Olivier Deprez <olivier.deprez@arm.com>
Link: https://lore.kernel.org/r/20230919-ffa_v1-1_notif-v2-13-6f3a3ca3923c@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

drivers/firmware/arm_ffa/driver.c

@@ -397,6 +397,19 @@ static u32 ffa_get_num_pages_sg(struct scatterlist *sg)
 	return num_pages;
 }
 
+static u8 ffa_memory_attributes_get(u32 func_id)
+{
+	/*
+	 * For the memory lend or donate operation, if the receiver is a PE or
+	 * a proxy endpoint, the owner/sender must not specify the attributes
+	 */
+	if (func_id == FFA_FN_NATIVE(MEM_LEND) ||
+	    func_id == FFA_MEM_LEND)
+		return 0;
+
+	return FFA_MEM_NORMAL | FFA_MEM_WRITE_BACK | FFA_MEM_INNER_SHAREABLE;
+}
+
 static int
 ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
 		       struct ffa_mem_ops_args *args)
@@ -413,8 +426,7 @@ ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
 	mem_region->tag = args->tag;
 	mem_region->flags = args->flags;
 	mem_region->sender_id = drv_info->vm_id;
-	mem_region->attributes = FFA_MEM_NORMAL | FFA_MEM_WRITE_BACK |
-				 FFA_MEM_INNER_SHAREABLE;
+	mem_region->attributes = ffa_memory_attributes_get(func_id);
 	ep_mem_access = &mem_region->ep_mem_access[0];
 
 	for (idx = 0; idx < args->nattrs; idx++, ep_mem_access++) {