[PATCH 12/12] thunderbolt: Scan and activate one PCI device

From: Andreas Noever
Date: Thu Nov 28 2013 - 20:39:51 EST


Use the tb_pci_* methods introduces in the last patch to activate
a the first PCI device on every plugged in thunderbolt device.

Signed-off-by: Andreas Noever <andreas.noever@xxxxxxxxx>
---
drivers/thunderbolt/tb.c | 118 +++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 115 insertions(+), 3 deletions(-)

diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index 9f25935..0e82afd 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -838,6 +838,109 @@ static void destroy_invalid_tunnels(struct tb *tb)
}
}

+/**
+ * find_pci_up_port() - return the first PCIe up port on @sw
+ */
+static struct tb_port *find_pci_up_port(struct tb_switch *sw)
+{
+ int i;
+ for (i = 1; i <= sw->config.max_port_number; i++)
+ if (sw->ports[i].config.type == TB_TYPE_PCIE_UP)
+ return &sw->ports[i];
+ return NULL;
+}
+
+/**
+ * find_unused_down_port() - return the first inactive PCIe down port on @sw
+ */
+static struct tb_port *find_unused_down_port(struct tb_switch *sw)
+{
+ int i;
+ int cap;
+ int res;
+ int data;
+ for (i = 1; i <= sw->config.max_port_number; i++) {
+ if (tb_is_upstream_port(&sw->ports[i]))
+ continue;
+ if (sw->ports[i].config.type != TB_TYPE_PCIE_DOWN)
+ continue;
+ cap = tb_find_cap(&sw->ports[i], TB_CFG_PORT, TB_CAP_PCIE);
+ if (cap <= 0)
+ continue;
+ res = tb_port_read(&sw->ports[i], &data, TB_CFG_PORT, cap, 1);
+ if (res < 0)
+ continue;
+ if (data & 0x80000000)
+ continue;
+ return &sw->ports[i];
+ }
+ return NULL;
+}
+
+/**
+ * tb_activate_pcie_devices() - scan for and activate PCIe devices
+ *
+ * This method is somewhat ad hoc. For now it only supports one device
+ * per port and only devices at depth 1.
+ */
+static void tb_activate_pcie_devices(struct tb *tb)
+{
+ int i;
+ int cap;
+ u32 data;
+ struct tb_switch *sw;
+ struct tb_port *up_port;
+ struct tb_port *down_port;
+ struct tb_pci_tunnel *tunnel;
+ /* scan for pcie devices at depth 1*/
+ for (i = 1; i <= tb->root_switch->config.max_port_number; i++) {
+ if (tb_is_upstream_port(&tb->root_switch->ports[i]))
+ continue;
+ if (tb->root_switch->ports[i].config.type != TB_TYPE_PORT)
+ continue;
+ if (!tb->root_switch->ports[i].remote)
+ continue;
+ sw = tb->root_switch->ports[i].remote->sw;
+ up_port = find_pci_up_port(sw);
+ if (!up_port) {
+ tb_sw_info(sw, "no PCIe devices found, aborting\n");
+ continue;
+ }
+
+ /* check whether port is already activated */
+ cap = tb_find_cap(up_port, TB_CFG_PORT, TB_CAP_PCIE);
+ if (cap <= 0)
+ continue;
+ if (tb_port_read(up_port, &data, TB_CFG_PORT, cap, 1))
+ continue;
+ if (data & 0x80000000) {
+ tb_port_info(up_port,
+ "PCIe port already activated, aborting\n");
+ continue;
+ }
+
+ down_port = find_unused_down_port(tb->root_switch);
+ if (!down_port) {
+ tb_port_info(up_port,
+ "All PCIe down ports are occupied, aborting\n");
+ continue;
+ }
+ tunnel = tb_pci_alloc(tb, up_port, down_port);
+ if (!tunnel) {
+ tb_port_info(up_port,
+ "PCIe tunnel allocation failed, aborting\n");
+ continue;
+ }
+
+ if (tb_pci_activate(tunnel)) {
+ tb_port_info(up_port,
+ "PCIe tunnel activation failed, aborting\n");
+ tb_pci_free(tunnel);
+ }
+
+ }
+}
+
struct tb_hotplug_event {
struct work_struct work;
struct tb *tb;
@@ -901,8 +1004,16 @@ static void tb_handle_hotplug(struct work_struct *work)
} else {
tb_port_info(port, "hotplug: scanning\n");
tb_scan_port(port);
- if (!port->remote)
+ if (!port->remote) {
tb_port_info(port, "hotplug: no switch found\n");
+ } else if (port->remote->sw->config.depth > 1) {
+ tb_sw_warn(port->remote->sw,
+ "hotplug: chaining not supported\n");
+ } else {
+ tb_sw_info(port->remote->sw,
+ "hotplug: activating pcie devices\n");
+ tb_activate_pcie_devices(tb);
+ }
}
out:
mutex_unlock(&tb->lock);
@@ -972,8 +1083,8 @@ void thunderbolt_shutdown_and_free(struct tb *tb)
/**
* thunderbolt_alloc_and_start() - setup the thunderbolt bus
*
- * Allocates a tb_cfg control channel, initializes the root switch and enables
- * plug events.
+ * Allocates a tb_cfg control channel, initializes the root switch, enables
+ * plug events and activates pci devices.
*
* Return: Returns NULL on error.
*/
@@ -1014,6 +1125,7 @@ struct tb *thunderbolt_alloc_and_start(struct tb_nhi *nhi)
goto err_locked;

tb_scan_ports(tb->root_switch);
+ tb_activate_pcie_devices(tb);

mutex_unlock(&tb->lock);
return tb;
--
1.8.4.2

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