Commit 5bf722df authored by Mika Westerberg's avatar Mika Westerberg
Browse files

thunderbolt: Make it possible to allocate one directional DMA tunnel 



With DMA tunnels it is possible that the service using it does not
require bi-directional paths so make RX and TX optional (but of course
one of them needs to be set).

Signed-off-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: default avatarYehezkel Bernat <YehezkelShB@gmail.com>
Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 407ac931

drivers/thunderbolt/tunnel.c

+31 −19
Original line number Diff line number Diff line
@@ -34,9 +34,6 @@ 
#define TB_DP_AUX_PATH_OUT		1

#define TB_DP_AUX_PATH_IN		2



#define TB_DMA_PATH_OUT			0

#define TB_DMA_PATH_IN			1



static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA", "USB3" };



#define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...)                   \
@@ -829,10 +826,10 @@ static void tb_dma_init_path(struct tb_path *path, unsigned int isb, 
 * @nhi: Host controller port

 * @dst: Destination null port which the other domain is connected to

 * @transmit_ring: NHI ring number used to send packets towards the

 *		   other domain

 *		   other domain. Set to %0 if TX path is not needed.

 * @transmit_path: HopID used for transmitting packets

 * @receive_ring: NHI ring number used to receive packets from the

 *		  other domain

 *		  other domain. Set to %0 if RX path is not needed.

 * @reveive_path: HopID used for receiving packets

 *

 * Return: Returns a tb_tunnel on success or NULL on failure.
@@ -843,10 +840,19 @@ struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi, 
				      int receive_path)

{

	struct tb_tunnel *tunnel;

	size_t npaths = 0, i = 0;

	struct tb_path *path;

	u32 credits;



	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_DMA);

	if (receive_ring)

		npaths++;

	if (transmit_ring)

		npaths++;



	if (WARN_ON(!npaths))

		return NULL;



	tunnel = tb_tunnel_alloc(tb, npaths, TB_TUNNEL_DMA);

	if (!tunnel)

		return NULL;
@@ -856,22 +862,28 @@ struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi, 


	credits = tb_dma_credits(nhi);



	path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0, "DMA RX");

	if (receive_ring) {

		path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0,

				     "DMA RX");

		if (!path) {

			tb_tunnel_free(tunnel);

			return NULL;

		}

		tb_dma_init_path(path, TB_PATH_NONE, TB_PATH_SOURCE | TB_PATH_INTERNAL,

				 credits);

	tunnel->paths[TB_DMA_PATH_IN] = path;

		tunnel->paths[i++] = path;

	}



	path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0, "DMA TX");

	if (transmit_ring) {

		path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0,

				     "DMA TX");

		if (!path) {

			tb_tunnel_free(tunnel);

			return NULL;

		}

		tb_dma_init_path(path, TB_PATH_SOURCE, TB_PATH_ALL, credits);

	tunnel->paths[TB_DMA_PATH_OUT] = path;

		tunnel->paths[i++] = path;

	}



	return tunnel;

}