To list the databases and logins
List all databases

select * from sys.databases


List SSRS Reports

use [ReportServer]

SELECT * FROM [dbo].[Catalog]
WHERE [Type] = 2
ORDER BY [Path]


List all Logins

select * from sys.syslogins


List users having permission to reports
from stackoverflow link 
https://stackoverflow.com/questions/6600480/ssrs-determine-report-permissions-via-reportserver-database-tables

    select C.UserName, D.RoleName, D.Description, E.Path, E.Name 
from dbo.PolicyUserRole A
   inner join dbo.Policies B on A.PolicyID = B.PolicyID
   inner join dbo.Users C on A.UserID = C.UserID
   inner join dbo.Roles D on A.RoleID = D.RoleID
   inner join dbo.Catalog E on A.PolicyID = E.PolicyID
order by C.UserName