Initial import

1 files changed, 232 insertions, 0 deletions

diff --git a/drivers/thunderbolt/tunnel_pci.c b/drivers/thunderbolt/tunnel_pci.c
new file mode 100644
index 000000000..baf1cd370
--- /dev/null
+++ b/drivers/thunderbolt/tunnel_pci.c
@@ -0,0 +1,232 @@
+/*
+ * 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_find_cap(port, TB_CFG_PORT, TB_CAP_PCIE);
+	if (cap <= 0) {
+		tb_port_warn(port, "TB_CAP_PCIE not found: %d\n", cap);
+		return cap ? cap : -ENXIO;
+	}
+	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)
+{
+	int res;
+	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;
+	}
+
+	res = tb_pci_restart(tunnel);
+	if (res)
+		return res;
+
+	list_add(&tunnel->list, &tunnel->tb->tunnel_list);
+	return 0;
+}
+
+
+
+/**
+ * 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);
+	list_del_init(&tunnel->list);
+}
+