linux/drivers/thunderbolt/tunnel_pci.c
Mika Westerberg 9d3cce0b61 thunderbolt: Introduce thunderbolt bus and connection manager
Thunderbolt fabric consists of one or more switches. This fabric is
called domain and it is controlled by an entity called connection
manager. The connection manager can be either internal (driven by a
firmware running on the host controller) or external (software driver).
This driver currently implements support for the latter.

In order to manage switches and their properties more easily we model
this domain structure as a Linux bus. Each host controller adds a domain
device to this bus, and these devices are named as domainN where N
stands for index or id of the current domain.

We then abstract connection manager specific operations into a new
structure tb_cm_ops and convert the existing tb.c to fill those
accordingly. This makes it easier to add support for the internal
connection manager in subsequent patches.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09 11:42:41 +02:00

226 lines
6.3 KiB
C

/*
* Thunderbolt Cactus Ridge driver - PCIe tunnel
*
* Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
*/
#include <linux/slab.h>
#include <linux/list.h>
#include "tunnel_pci.h"
#include "tb.h"
#define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...) \
do { \
struct tb_pci_tunnel *__tunnel = (tunnel); \
level(__tunnel->tb, "%llx:%x <-> %llx:%x (PCI): " fmt, \
tb_route(__tunnel->down_port->sw), \
__tunnel->down_port->port, \
tb_route(__tunnel->up_port->sw), \
__tunnel->up_port->port, \
## arg); \
} while (0)
#define tb_tunnel_WARN(tunnel, fmt, arg...) \
__TB_TUNNEL_PRINT(tb_WARN, tunnel, fmt, ##arg)
#define tb_tunnel_warn(tunnel, fmt, arg...) \
__TB_TUNNEL_PRINT(tb_warn, tunnel, fmt, ##arg)
#define tb_tunnel_info(tunnel, fmt, arg...) \
__TB_TUNNEL_PRINT(tb_info, tunnel, fmt, ##arg)
static void tb_pci_init_path(struct tb_path *path)
{
path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
path->egress_shared_buffer = TB_PATH_NONE;
path->ingress_fc_enable = TB_PATH_ALL;
path->ingress_shared_buffer = TB_PATH_NONE;
path->priority = 3;
path->weight = 1;
path->drop_packages = 0;
path->nfc_credits = 0;
}
/**
* tb_pci_alloc() - allocate a pci tunnel
*
* Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and
* TB_TYPE_PCIE_DOWN.
*
* Currently only paths consisting of two hops are supported (that is the
* ports must be on "adjacent" switches).
*
* The paths are hard-coded to use hop 8 (the only working hop id available on
* my thunderbolt devices). Therefore at most ONE path per device may be
* activated.
*
* Return: Returns a tb_pci_tunnel on success or NULL on failure.
*/
struct tb_pci_tunnel *tb_pci_alloc(struct tb *tb, struct tb_port *up,
struct tb_port *down)
{
struct tb_pci_tunnel *tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
if (!tunnel)
goto err;
tunnel->tb = tb;
tunnel->down_port = down;
tunnel->up_port = up;
INIT_LIST_HEAD(&tunnel->list);
tunnel->path_to_up = tb_path_alloc(up->sw->tb, 2);
if (!tunnel->path_to_up)
goto err;
tunnel->path_to_down = tb_path_alloc(up->sw->tb, 2);
if (!tunnel->path_to_down)
goto err;
tb_pci_init_path(tunnel->path_to_up);
tb_pci_init_path(tunnel->path_to_down);
tunnel->path_to_up->hops[0].in_port = down;
tunnel->path_to_up->hops[0].in_hop_index = 8;
tunnel->path_to_up->hops[0].in_counter_index = -1;
tunnel->path_to_up->hops[0].out_port = tb_upstream_port(up->sw)->remote;
tunnel->path_to_up->hops[0].next_hop_index = 8;
tunnel->path_to_up->hops[1].in_port = tb_upstream_port(up->sw);
tunnel->path_to_up->hops[1].in_hop_index = 8;
tunnel->path_to_up->hops[1].in_counter_index = -1;
tunnel->path_to_up->hops[1].out_port = up;
tunnel->path_to_up->hops[1].next_hop_index = 8;
tunnel->path_to_down->hops[0].in_port = up;
tunnel->path_to_down->hops[0].in_hop_index = 8;
tunnel->path_to_down->hops[0].in_counter_index = -1;
tunnel->path_to_down->hops[0].out_port = tb_upstream_port(up->sw);
tunnel->path_to_down->hops[0].next_hop_index = 8;
tunnel->path_to_down->hops[1].in_port =
tb_upstream_port(up->sw)->remote;
tunnel->path_to_down->hops[1].in_hop_index = 8;
tunnel->path_to_down->hops[1].in_counter_index = -1;
tunnel->path_to_down->hops[1].out_port = down;
tunnel->path_to_down->hops[1].next_hop_index = 8;
return tunnel;
err:
if (tunnel) {
if (tunnel->path_to_down)
tb_path_free(tunnel->path_to_down);
if (tunnel->path_to_up)
tb_path_free(tunnel->path_to_up);
kfree(tunnel);
}
return NULL;
}
/**
* tb_pci_free() - free a tunnel
*
* The tunnel must have been deactivated.
*/
void tb_pci_free(struct tb_pci_tunnel *tunnel)
{
if (tunnel->path_to_up->activated || tunnel->path_to_down->activated) {
tb_tunnel_WARN(tunnel, "trying to free an activated tunnel\n");
return;
}
tb_path_free(tunnel->path_to_up);
tb_path_free(tunnel->path_to_down);
kfree(tunnel);
}
/**
* tb_pci_is_invalid - check whether an activated path is still valid
*/
bool tb_pci_is_invalid(struct tb_pci_tunnel *tunnel)
{
WARN_ON(!tunnel->path_to_up->activated);
WARN_ON(!tunnel->path_to_down->activated);
return tb_path_is_invalid(tunnel->path_to_up)
|| tb_path_is_invalid(tunnel->path_to_down);
}
/**
* tb_pci_port_active() - activate/deactivate PCI capability
*
* Return: Returns 0 on success or an error code on failure.
*/
static int tb_pci_port_active(struct tb_port *port, bool active)
{
u32 word = active ? 0x80000000 : 0x0;
int cap = tb_port_find_cap(port, TB_PORT_CAP_ADAP);
if (cap < 0) {
tb_port_warn(port, "TB_PORT_CAP_ADAP not found: %d\n", cap);
return cap;
}
return tb_port_write(port, &word, TB_CFG_PORT, cap, 1);
}
/**
* tb_pci_restart() - activate a tunnel after a hardware reset
*/
int tb_pci_restart(struct tb_pci_tunnel *tunnel)
{
int res;
tunnel->path_to_up->activated = false;
tunnel->path_to_down->activated = false;
tb_tunnel_info(tunnel, "activating\n");
res = tb_path_activate(tunnel->path_to_up);
if (res)
goto err;
res = tb_path_activate(tunnel->path_to_down);
if (res)
goto err;
res = tb_pci_port_active(tunnel->down_port, true);
if (res)
goto err;
res = tb_pci_port_active(tunnel->up_port, true);
if (res)
goto err;
return 0;
err:
tb_tunnel_warn(tunnel, "activation failed\n");
tb_pci_deactivate(tunnel);
return res;
}
/**
* tb_pci_activate() - activate a tunnel
*
* Return: Returns 0 on success or an error code on failure.
*/
int tb_pci_activate(struct tb_pci_tunnel *tunnel)
{
if (tunnel->path_to_up->activated || tunnel->path_to_down->activated) {
tb_tunnel_WARN(tunnel,
"trying to activate an already activated tunnel\n");
return -EINVAL;
}
return tb_pci_restart(tunnel);
}
/**
* tb_pci_deactivate() - deactivate a tunnel
*/
void tb_pci_deactivate(struct tb_pci_tunnel *tunnel)
{
tb_tunnel_info(tunnel, "deactivating\n");
/*
* TODO: enable reset by writing 0x04000000 to TB_CAP_PCIE + 1 on up
* port. Seems to have no effect?
*/
tb_pci_port_active(tunnel->up_port, false);
tb_pci_port_active(tunnel->down_port, false);
if (tunnel->path_to_down->activated)
tb_path_deactivate(tunnel->path_to_down);
if (tunnel->path_to_up->activated)
tb_path_deactivate(tunnel->path_to_up);
}