[PATCH v3 05/15] thunderbolt: Initialize root switch and ports

[Andreas Noever <andreas.noever@gmail.com>]

This patch adds the structures tb_switch and tb_port as well as code to
initialize the root switch.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
---
 drivers/thunderbolt/Makefile |   2 +-
 drivers/thunderbolt/switch.c | 186 +++++++++++++++++++++++++++++++++++++++++++
 drivers/thunderbolt/tb.c     |   8 ++
 drivers/thunderbolt/tb.h     | 138 ++++++++++++++++++++++++++++++++
 4 files changed, 333 insertions(+), 1 deletion(-)
 create mode 100644 drivers/thunderbolt/switch.c

diff --git a/drivers/thunderbolt/Makefile b/drivers/thunderbolt/Makefile
index 1f996bb..4ac18d9 100644
--- a/drivers/thunderbolt/Makefile
+++ b/drivers/thunderbolt/Makefile
@@ -1,3 +1,3 @@
 obj-${CONFIG_THUNDERBOLT} := thunderbolt.o
-thunderbolt-objs := nhi.o ctl.o tb.o
+thunderbolt-objs := nhi.o ctl.o tb.o switch.o
 
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
new file mode 100644
index 0000000..e89121f
--- /dev/null
+++ b/drivers/thunderbolt/switch.c
@@ -0,0 +1,186 @@
+/*
+ * Thunderbolt Cactus Ridge driver - switch/port utility functions
+ *
+ * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
+ */
+
+#include <linux/delay.h>
+
+#include "tb.h"
+
+/* port utility functions */
+
+static const char *tb_port_type(struct tb_regs_port_header *port)
+{
+	switch (port->type >> 16) {
+	case 0:
+		switch ((u8) port->type) {
+		case 0:
+			return "Inactive";
+		case 1:
+			return "Port";
+		case 2:
+			return "NHI";
+		default:
+			return "unknown";
+		}
+	case 0x2:
+		return "Ethernet";
+	case 0x8:
+		return "SATA";
+	case 0xe:
+		return "DP/HDMI";
+	case 0x10:
+		return "PCIe";
+	case 0x20:
+		return "USB";
+	default:
+		return "unknown";
+	}
+}
+
+static void tb_dump_port(struct tb *tb, struct tb_regs_port_header *port)
+{
+	tb_info(tb,
+		" Port %d: %x:%x (Revision: %d, TB Version: %d, Type: %s (%#x))\n",
+		port->port_number, port->vendor_id, port->device_id,
+		port->revision, port->thunderbolt_version, tb_port_type(port),
+		port->type);
+	tb_info(tb, "  Max hop id (in/out): %d/%d\n",
+		port->max_in_hop_id, port->max_out_hop_id);
+	tb_info(tb, "  Max counters: %d\n", port->max_counters);
+	tb_info(tb, "  NFC Credits: %#x\n", port->nfc_credits);
+}
+
+/**
+ * tb_init_port() - initialize a port
+ *
+ * This is a helper method for tb_switch_alloc. Does not check or initialize
+ * any downstream switches.
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+static int tb_init_port(struct tb_switch *sw, u8 port_nr)
+{
+	int res;
+	struct tb_port *port = &sw->ports[port_nr];
+	port->sw = sw;
+	port->port = port_nr;
+	port->remote = NULL;
+	res = tb_port_read(port, &port->config, TB_CFG_PORT, 0, 8);
+	if (res)
+		return res;
+
+	tb_dump_port(sw->tb, &port->config);
+
+	/* TODO: Read dual link port, DP port and more from EEPROM. */
+	return 0;
+
+}
+
+/* switch utility functions */
+
+static void tb_dump_switch(struct tb *tb, struct tb_regs_switch_header *sw)
+{
+	tb_info(tb,
+		" Switch: %x:%x (Revision: %d, TB Version: %d)\n",
+		sw->vendor_id, sw->device_id, sw->revision,
+		sw->thunderbolt_version);
+	tb_info(tb, "  Max Port Number: %d\n", sw->max_port_number);
+	tb_info(tb, "  Config:\n");
+	tb_info(tb,
+		"   Upstream Port Number: %d Depth: %d Route String: %#llx Enabled: %d, PlugEventsDelay: %dms\n",
+		sw->upstream_port_number, sw->depth,
+		(((u64) sw->route_hi) << 32) | sw->route_lo,
+		sw->enabled, sw->plug_events_delay);
+	tb_info(tb,
+		"   unknown1: %#x unknown4: %#x\n",
+		sw->__unknown1, sw->__unknown4);
+}
+
+/**
+ * tb_switch_free() - free a tb_switch and all downstream switches
+ */
+void tb_switch_free(struct tb_switch *sw)
+{
+	int i;
+	/* port 0 is the switch itself and never has a remote */
+	for (i = 1; i <= sw->config.max_port_number; i++) {
+		if (tb_is_upstream_port(&sw->ports[i]))
+			continue;
+		if (sw->ports[i].remote)
+			tb_switch_free(sw->ports[i].remote->sw);
+		sw->ports[i].remote = NULL;
+	}
+
+	kfree(sw->ports);
+	kfree(sw);
+}
+
+/**
+ * tb_switch_alloc() - allocate and initialize a switch
+ *
+ * Return: Returns a NULL on failure.
+ */
+struct tb_switch *tb_switch_alloc(struct tb *tb, u64 route)
+{
+	int i;
+	struct tb_switch *sw;
+	int upstream_port = tb_cfg_get_upstream_port(tb->ctl, route);
+	if (upstream_port < 0)
+		return NULL;
+
+	sw = kzalloc(sizeof(*sw), GFP_KERNEL);
+	if (!sw)
+		return NULL;
+
+	sw->tb = tb;
+	if (tb_cfg_read(tb->ctl, &sw->config, route, 0, 2, 0, 5))
+		goto err;
+	tb_info(tb,
+		"initializing Switch at %#llx (depth: %d, up port: %d)\n",
+		route, tb_route_length(route), upstream_port);
+	tb_info(tb, "old switch config:\n");
+	tb_dump_switch(tb, &sw->config);
+
+	/* configure switch */
+	sw->config.upstream_port_number = upstream_port;
+	sw->config.depth = tb_route_length(route);
+	sw->config.route_lo = route;
+	sw->config.route_hi = route >> 32;
+	sw->config.enabled = 1;
+	/* from here on we may use the tb_sw_* functions & macros */
+
+	if (sw->config.vendor_id != 0x8086)
+		tb_sw_warn(sw, "unknown switch vendor id %#x\n",
+			   sw->config.vendor_id);
+
+	if (sw->config.device_id != 0x1547 && sw->config.device_id != 0x1549)
+		tb_sw_warn(sw, "unsupported switch device id %#x\n",
+			   sw->config.device_id);
+
+	/* upload configuration */
+	if (tb_sw_write(sw, 1 + (u32 *) &sw->config, TB_CFG_SWITCH, 1, 3))
+		goto err;
+
+	/* initialize ports */
+	sw->ports = kcalloc(sw->config.max_port_number + 1, sizeof(*sw->ports),
+	GFP_KERNEL);
+	if (!sw->ports)
+		goto err;
+
+	for (i = 0; i <= sw->config.max_port_number; i++) {
+		if (tb_init_port(sw, i))
+			goto err;
+		/* TODO: check if port is disabled (EEPROM) */
+	}
+
+	/* TODO: I2C, IECS, EEPROM, link controller */
+
+	return sw;
+err:
+	kfree(sw->ports);
+	kfree(sw);
+	return NULL;
+}
+
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index 164dea0..f1b6100 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -71,6 +71,10 @@ void thunderbolt_shutdown_and_free(struct tb *tb)
 {
 	mutex_lock(&tb->lock);
 
+	if (tb->root_switch)
+		tb_switch_free(tb->root_switch);
+	tb->root_switch = NULL;
+
 	if (tb->ctl) {
 		tb_ctl_stop(tb->ctl);
 		tb_ctl_free(tb->ctl);
@@ -126,6 +130,10 @@ struct tb *thunderbolt_alloc_and_start(struct tb_nhi *nhi)
 	 */
 	tb_ctl_start(tb->ctl);
 
+	tb->root_switch = tb_switch_alloc(tb, 0);
+	if (!tb->root_switch)
+		goto err_locked;
+
 	/* Allow tb_handle_hotplug to progress events */
 	tb->hotplug_active = true;
 	mutex_unlock(&tb->lock);
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 6055dfd..389dbb4 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -7,9 +7,31 @@
 #ifndef TB_H_
 #define TB_H_
 
+#include <linux/pci.h>
+
+#include "tb_regs.h"
 #include "ctl.h"
 
 /**
+ * struct tb_switch - a thunderbolt switch
+ */
+struct tb_switch {
+	struct tb_regs_switch_header config;
+	struct tb_port *ports;
+	struct tb *tb;
+};
+
+/**
+ * struct tb_port - a thunderbolt port, part of a tb_switch
+ */
+struct tb_port {
+	struct tb_regs_port_header config;
+	struct tb_switch *sw;
+	struct tb_port *remote; /* remote port, NULL if not connected */
+	u8 port; /* port number on switch */
+};
+
+/**
  * struct tb - main thunderbolt bus structure
  */
 struct tb {
@@ -20,6 +42,7 @@ struct tb {
 	struct tb_nhi *nhi;
 	struct tb_ctl *ctl;
 	struct workqueue_struct *wq; /* ordered workqueue for plug events */
+	struct tb_switch *root_switch;
 	bool hotplug_active; /*
 			      * tb_handle_hotplug will stop progressing plug
 			      * events and exit if this is not set (it needs to
@@ -29,7 +52,122 @@ struct tb {
 
 };
 
+/* helper functions & macros */
+
+/**
+ * tb_upstream_port() - return the upstream port of a switch
+ *
+ * Every switch has an upstream port (for the root switch it is the NHI).
+ *
+ * During switch alloc/init tb_upstream_port()->remote may be NULL, even for
+ * non root switches (on the NHI port remote is always NULL).
+ *
+ * Return: Returns the upstream port of the switch.
+ */
+static inline struct tb_port *tb_upstream_port(struct tb_switch *sw)
+{
+	return &sw->ports[sw->config.upstream_port_number];
+}
+
+static inline u64 tb_route(struct tb_switch *sw)
+{
+	return ((u64) sw->config.route_hi) << 32 | sw->config.route_lo;
+}
+
+static inline int tb_sw_read(struct tb_switch *sw, void *buffer,
+			     enum tb_cfg_space space, u32 offset, u32 length)
+{
+	return tb_cfg_read(sw->tb->ctl,
+			   buffer,
+			   tb_route(sw),
+			   0,
+			   space,
+			   offset,
+			   length);
+}
+
+static inline int tb_sw_write(struct tb_switch *sw, void *buffer,
+			      enum tb_cfg_space space, u32 offset, u32 length)
+{
+	return tb_cfg_write(sw->tb->ctl,
+			    buffer,
+			    tb_route(sw),
+			    0,
+			    space,
+			    offset,
+			    length);
+}
+
+static inline int tb_port_read(struct tb_port *port, void *buffer,
+			       enum tb_cfg_space space, u32 offset, u32 length)
+{
+	return tb_cfg_read(port->sw->tb->ctl,
+			   buffer,
+			   tb_route(port->sw),
+			   port->port,
+			   space,
+			   offset,
+			   length);
+}
+
+static inline int tb_port_write(struct tb_port *port, void *buffer,
+				enum tb_cfg_space space, u32 offset, u32 length)
+{
+	return tb_cfg_write(port->sw->tb->ctl,
+			    buffer,
+			    tb_route(port->sw),
+			    port->port,
+			    space,
+			    offset,
+			    length);
+}
+
+#define tb_err(tb, fmt, arg...) dev_err(&(tb)->nhi->pdev->dev, fmt, ## arg)
+#define tb_WARN(tb, fmt, arg...) dev_WARN(&(tb)->nhi->pdev->dev, fmt, ## arg)
+#define tb_warn(tb, fmt, arg...) dev_warn(&(tb)->nhi->pdev->dev, fmt, ## arg)
+#define tb_info(tb, fmt, arg...) dev_info(&(tb)->nhi->pdev->dev, fmt, ## arg)
+
+
+#define __TB_SW_PRINT(level, sw, fmt, arg...)           \
+	do {                                            \
+		struct tb_switch *__sw = (sw);          \
+		level(__sw->tb, "%llx: " fmt,           \
+		      tb_route(__sw), ## arg);          \
+	} while (0)
+#define tb_sw_WARN(sw, fmt, arg...) __TB_SW_PRINT(tb_WARN, sw, fmt, ##arg)
+#define tb_sw_warn(sw, fmt, arg...) __TB_SW_PRINT(tb_warn, sw, fmt, ##arg)
+#define tb_sw_info(sw, fmt, arg...) __TB_SW_PRINT(tb_info, sw, fmt, ##arg)
+
+
+#define __TB_PORT_PRINT(level, _port, fmt, arg...)                      \
+	do {                                                            \
+		struct tb_port *__port = (_port);                       \
+		level(__port->sw->tb, "%llx:%x: " fmt,                  \
+		      tb_route(__port->sw), __port->port, ## arg);      \
+	} while (0)
+#define tb_port_WARN(port, fmt, arg...) \
+	__TB_PORT_PRINT(tb_WARN, port, fmt, ##arg)
+#define tb_port_warn(port, fmt, arg...) \
+	__TB_PORT_PRINT(tb_warn, port, fmt, ##arg)
+#define tb_port_info(port, fmt, arg...) \
+	__TB_PORT_PRINT(tb_info, port, fmt, ##arg)
+
+
 struct tb *thunderbolt_alloc_and_start(struct tb_nhi *nhi);
 void thunderbolt_shutdown_and_free(struct tb *tb);
 
+struct tb_switch *tb_switch_alloc(struct tb *tb, u64 route);
+void tb_switch_free(struct tb_switch *sw);
+
+
+static inline int tb_route_length(u64 route)
+{
+	return (fls64(route) + TB_ROUTE_SHIFT - 1) / TB_ROUTE_SHIFT;
+}
+
+static inline bool tb_is_upstream_port(struct tb_port *port)
+{
+	return port == tb_upstream_port(port->sw);
+}
+
 #endif
-- 
1.9.3