Count Number Of 'd'

i just want one row instead of multiple rows results.

declare @name varchar(30)
declare @count int
declare @a int
set @name = 'dennis dennis'
set @count = 0
set @a = 1


while(@count < len(@name))
begin
select count(substring(@name, @a, 1)), substring(@name, @a, 1)
where substring(@name, @a, 1) = 'd'


select @count = @count +1
select @a = @a+1

end