linux/drivers/thunderbolt/tunnel.c
Mika Westerberg a11b88add4 thunderbolt: Add bandwidth management for Display Port tunnels
Titan Ridge supports Display Port 1.4 which adds HBR3 (High Bit Rate)
rates that may be up to 8.1 Gb/s over 4 lanes. This translates to
effective data bandwidth of 25.92 Gb/s (as 8/10 encoding is removed by
the DP adapters when going over Thunderbolt fabric). If another high
rate monitor is connected we may need to reduce the bandwidth it
consumes so that it fits into the total 40 Gb/s available on the
Thunderbolt fabric.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2019-11-02 12:13:31 +03:00

1032 lines
25 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Thunderbolt driver - Tunneling support
*
* Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
* Copyright (C) 2019, Intel Corporation
*/
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/list.h>
#include "tunnel.h"
#include "tb.h"
/* PCIe adapters use always HopID of 8 for both directions */
#define TB_PCI_HOPID 8
#define TB_PCI_PATH_DOWN 0
#define TB_PCI_PATH_UP 1
/* DP adapters use HopID 8 for AUX and 9 for Video */
#define TB_DP_AUX_TX_HOPID 8
#define TB_DP_AUX_RX_HOPID 8
#define TB_DP_VIDEO_HOPID 9
#define TB_DP_VIDEO_PATH_OUT 0
#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" };
#define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...) \
do { \
struct tb_tunnel *__tunnel = (tunnel); \
level(__tunnel->tb, "%llx:%x <-> %llx:%x (%s): " fmt, \
tb_route(__tunnel->src_port->sw), \
__tunnel->src_port->port, \
tb_route(__tunnel->dst_port->sw), \
__tunnel->dst_port->port, \
tb_tunnel_names[__tunnel->type], \
## 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)
#define tb_tunnel_dbg(tunnel, fmt, arg...) \
__TB_TUNNEL_PRINT(tb_dbg, tunnel, fmt, ##arg)
static struct tb_tunnel *tb_tunnel_alloc(struct tb *tb, size_t npaths,
enum tb_tunnel_type type)
{
struct tb_tunnel *tunnel;
tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
if (!tunnel)
return NULL;
tunnel->paths = kcalloc(npaths, sizeof(tunnel->paths[0]), GFP_KERNEL);
if (!tunnel->paths) {
tb_tunnel_free(tunnel);
return NULL;
}
INIT_LIST_HEAD(&tunnel->list);
tunnel->tb = tb;
tunnel->npaths = npaths;
tunnel->type = type;
return tunnel;
}
static int tb_pci_activate(struct tb_tunnel *tunnel, bool activate)
{
int res;
res = tb_pci_port_enable(tunnel->src_port, activate);
if (res)
return res;
if (tb_port_is_pcie_up(tunnel->dst_port))
return tb_pci_port_enable(tunnel->dst_port, activate);
return 0;
}
static int tb_initial_credits(const struct tb_switch *sw)
{
/* If the path is complete sw is not NULL */
if (sw) {
/* More credits for faster link */
switch (sw->link_speed * sw->link_width) {
case 40:
return 32;
case 20:
return 24;
}
}
return 16;
}
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;
path->hops[0].initial_credits = 7;
path->hops[1].initial_credits =
tb_initial_credits(path->hops[1].in_port->sw);
}
/**
* tb_tunnel_discover_pci() - Discover existing PCIe tunnels
* @tb: Pointer to the domain structure
* @down: PCIe downstream adapter
*
* If @down adapter is active, follows the tunnel to the PCIe upstream
* adapter and back. Returns the discovered tunnel or %NULL if there was
* no tunnel.
*/
struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down)
{
struct tb_tunnel *tunnel;
struct tb_path *path;
if (!tb_pci_port_is_enabled(down))
return NULL;
tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
if (!tunnel)
return NULL;
tunnel->activate = tb_pci_activate;
tunnel->src_port = down;
/*
* Discover both paths even if they are not complete. We will
* clean them up by calling tb_tunnel_deactivate() below in that
* case.
*/
path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1,
&tunnel->dst_port, "PCIe Up");
if (!path) {
/* Just disable the downstream port */
tb_pci_port_enable(down, false);
goto err_free;
}
tunnel->paths[TB_PCI_PATH_UP] = path;
tb_pci_init_path(tunnel->paths[TB_PCI_PATH_UP]);
path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL,
"PCIe Down");
if (!path)
goto err_deactivate;
tunnel->paths[TB_PCI_PATH_DOWN] = path;
tb_pci_init_path(tunnel->paths[TB_PCI_PATH_DOWN]);
/* Validate that the tunnel is complete */
if (!tb_port_is_pcie_up(tunnel->dst_port)) {
tb_port_warn(tunnel->dst_port,
"path does not end on a PCIe adapter, cleaning up\n");
goto err_deactivate;
}
if (down != tunnel->src_port) {
tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
goto err_deactivate;
}
if (!tb_pci_port_is_enabled(tunnel->dst_port)) {
tb_tunnel_warn(tunnel,
"tunnel is not fully activated, cleaning up\n");
goto err_deactivate;
}
tb_tunnel_dbg(tunnel, "discovered\n");
return tunnel;
err_deactivate:
tb_tunnel_deactivate(tunnel);
err_free:
tb_tunnel_free(tunnel);
return NULL;
}
/**
* tb_tunnel_alloc_pci() - allocate a pci tunnel
* @tb: Pointer to the domain structure
* @up: PCIe upstream adapter port
* @down: PCIe downstream adapter port
*
* Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and
* TB_TYPE_PCIE_DOWN.
*
* Return: Returns a tb_tunnel on success or NULL on failure.
*/
struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
struct tb_port *down)
{
struct tb_tunnel *tunnel;
struct tb_path *path;
tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
if (!tunnel)
return NULL;
tunnel->activate = tb_pci_activate;
tunnel->src_port = down;
tunnel->dst_port = up;
path = tb_path_alloc(tb, down, TB_PCI_HOPID, up, TB_PCI_HOPID, 0,
"PCIe Down");
if (!path) {
tb_tunnel_free(tunnel);
return NULL;
}
tb_pci_init_path(path);
tunnel->paths[TB_PCI_PATH_DOWN] = path;
path = tb_path_alloc(tb, up, TB_PCI_HOPID, down, TB_PCI_HOPID, 0,
"PCIe Up");
if (!path) {
tb_tunnel_free(tunnel);
return NULL;
}
tb_pci_init_path(path);
tunnel->paths[TB_PCI_PATH_UP] = path;
return tunnel;
}
static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out)
{
int timeout = 10;
u32 val;
int ret;
/* Both ends need to support this */
if (!tb_switch_is_titan_ridge(in->sw) ||
!tb_switch_is_titan_ridge(out->sw))
return 0;
ret = tb_port_read(out, &val, TB_CFG_PORT,
out->cap_adap + DP_STATUS_CTRL, 1);
if (ret)
return ret;
val |= DP_STATUS_CTRL_UF | DP_STATUS_CTRL_CMHS;
ret = tb_port_write(out, &val, TB_CFG_PORT,
out->cap_adap + DP_STATUS_CTRL, 1);
if (ret)
return ret;
do {
ret = tb_port_read(out, &val, TB_CFG_PORT,
out->cap_adap + DP_STATUS_CTRL, 1);
if (ret)
return ret;
if (!(val & DP_STATUS_CTRL_CMHS))
return 0;
usleep_range(10, 100);
} while (timeout--);
return -ETIMEDOUT;
}
static inline u32 tb_dp_cap_get_rate(u32 val)
{
u32 rate = (val & DP_COMMON_CAP_RATE_MASK) >> DP_COMMON_CAP_RATE_SHIFT;
switch (rate) {
case DP_COMMON_CAP_RATE_RBR:
return 1620;
case DP_COMMON_CAP_RATE_HBR:
return 2700;
case DP_COMMON_CAP_RATE_HBR2:
return 5400;
case DP_COMMON_CAP_RATE_HBR3:
return 8100;
default:
return 0;
}
}
static inline u32 tb_dp_cap_set_rate(u32 val, u32 rate)
{
val &= ~DP_COMMON_CAP_RATE_MASK;
switch (rate) {
default:
WARN(1, "invalid rate %u passed, defaulting to 1620 MB/s\n", rate);
/* Fallthrough */
case 1620:
val |= DP_COMMON_CAP_RATE_RBR << DP_COMMON_CAP_RATE_SHIFT;
break;
case 2700:
val |= DP_COMMON_CAP_RATE_HBR << DP_COMMON_CAP_RATE_SHIFT;
break;
case 5400:
val |= DP_COMMON_CAP_RATE_HBR2 << DP_COMMON_CAP_RATE_SHIFT;
break;
case 8100:
val |= DP_COMMON_CAP_RATE_HBR3 << DP_COMMON_CAP_RATE_SHIFT;
break;
}
return val;
}
static inline u32 tb_dp_cap_get_lanes(u32 val)
{
u32 lanes = (val & DP_COMMON_CAP_LANES_MASK) >> DP_COMMON_CAP_LANES_SHIFT;
switch (lanes) {
case DP_COMMON_CAP_1_LANE:
return 1;
case DP_COMMON_CAP_2_LANES:
return 2;
case DP_COMMON_CAP_4_LANES:
return 4;
default:
return 0;
}
}
static inline u32 tb_dp_cap_set_lanes(u32 val, u32 lanes)
{
val &= ~DP_COMMON_CAP_LANES_MASK;
switch (lanes) {
default:
WARN(1, "invalid number of lanes %u passed, defaulting to 1\n",
lanes);
/* Fallthrough */
case 1:
val |= DP_COMMON_CAP_1_LANE << DP_COMMON_CAP_LANES_SHIFT;
break;
case 2:
val |= DP_COMMON_CAP_2_LANES << DP_COMMON_CAP_LANES_SHIFT;
break;
case 4:
val |= DP_COMMON_CAP_4_LANES << DP_COMMON_CAP_LANES_SHIFT;
break;
}
return val;
}
static unsigned int tb_dp_bandwidth(unsigned int rate, unsigned int lanes)
{
/* Tunneling removes the DP 8b/10b encoding */
return rate * lanes * 8 / 10;
}
static int tb_dp_reduce_bandwidth(int max_bw, u32 in_rate, u32 in_lanes,
u32 out_rate, u32 out_lanes, u32 *new_rate,
u32 *new_lanes)
{
static const u32 dp_bw[][2] = {
/* Mb/s, lanes */
{ 8100, 4 }, /* 25920 Mb/s */
{ 5400, 4 }, /* 17280 Mb/s */
{ 8100, 2 }, /* 12960 Mb/s */
{ 2700, 4 }, /* 8640 Mb/s */
{ 5400, 2 }, /* 8640 Mb/s */
{ 8100, 1 }, /* 6480 Mb/s */
{ 1620, 4 }, /* 5184 Mb/s */
{ 5400, 1 }, /* 4320 Mb/s */
{ 2700, 2 }, /* 4320 Mb/s */
{ 1620, 2 }, /* 2592 Mb/s */
{ 2700, 1 }, /* 2160 Mb/s */
{ 1620, 1 }, /* 1296 Mb/s */
};
unsigned int i;
/*
* Find a combination that can fit into max_bw and does not
* exceed the maximum rate and lanes supported by the DP OUT and
* DP IN adapters.
*/
for (i = 0; i < ARRAY_SIZE(dp_bw); i++) {
if (dp_bw[i][0] > out_rate || dp_bw[i][1] > out_lanes)
continue;
if (dp_bw[i][0] > in_rate || dp_bw[i][1] > in_lanes)
continue;
if (tb_dp_bandwidth(dp_bw[i][0], dp_bw[i][1]) <= max_bw) {
*new_rate = dp_bw[i][0];
*new_lanes = dp_bw[i][1];
return 0;
}
}
return -ENOSR;
}
static int tb_dp_xchg_caps(struct tb_tunnel *tunnel)
{
u32 out_dp_cap, out_rate, out_lanes, in_dp_cap, in_rate, in_lanes, bw;
struct tb_port *out = tunnel->dst_port;
struct tb_port *in = tunnel->src_port;
int ret;
/*
* Copy DP_LOCAL_CAP register to DP_REMOTE_CAP register for
* newer generation hardware.
*/
if (in->sw->generation < 2 || out->sw->generation < 2)
return 0;
/*
* Perform connection manager handshake between IN and OUT ports
* before capabilities exchange can take place.
*/
ret = tb_dp_cm_handshake(in, out);
if (ret)
return ret;
/* Read both DP_LOCAL_CAP registers */
ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT,
in->cap_adap + DP_LOCAL_CAP, 1);
if (ret)
return ret;
ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT,
out->cap_adap + DP_LOCAL_CAP, 1);
if (ret)
return ret;
/* Write IN local caps to OUT remote caps */
ret = tb_port_write(out, &in_dp_cap, TB_CFG_PORT,
out->cap_adap + DP_REMOTE_CAP, 1);
if (ret)
return ret;
in_rate = tb_dp_cap_get_rate(in_dp_cap);
in_lanes = tb_dp_cap_get_lanes(in_dp_cap);
tb_port_dbg(in, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
in_rate, in_lanes, tb_dp_bandwidth(in_rate, in_lanes));
/*
* If the tunnel bandwidth is limited (max_bw is set) then see
* if we need to reduce bandwidth to fit there.
*/
out_rate = tb_dp_cap_get_rate(out_dp_cap);
out_lanes = tb_dp_cap_get_lanes(out_dp_cap);
bw = tb_dp_bandwidth(out_rate, out_lanes);
tb_port_dbg(out, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
out_rate, out_lanes, bw);
if (tunnel->max_bw && bw > tunnel->max_bw) {
u32 new_rate, new_lanes, new_bw;
ret = tb_dp_reduce_bandwidth(tunnel->max_bw, in_rate, in_lanes,
out_rate, out_lanes, &new_rate,
&new_lanes);
if (ret) {
tb_port_info(out, "not enough bandwidth for DP tunnel\n");
return ret;
}
new_bw = tb_dp_bandwidth(new_rate, new_lanes);
tb_port_dbg(out, "bandwidth reduced to %u Mb/s x%u = %u Mb/s\n",
new_rate, new_lanes, new_bw);
/*
* Set new rate and number of lanes before writing it to
* the IN port remote caps.
*/
out_dp_cap = tb_dp_cap_set_rate(out_dp_cap, new_rate);
out_dp_cap = tb_dp_cap_set_lanes(out_dp_cap, new_lanes);
}
return tb_port_write(in, &out_dp_cap, TB_CFG_PORT,
in->cap_adap + DP_REMOTE_CAP, 1);
}
static int tb_dp_activate(struct tb_tunnel *tunnel, bool active)
{
int ret;
if (active) {
struct tb_path **paths;
int last;
paths = tunnel->paths;
last = paths[TB_DP_VIDEO_PATH_OUT]->path_length - 1;
tb_dp_port_set_hops(tunnel->src_port,
paths[TB_DP_VIDEO_PATH_OUT]->hops[0].in_hop_index,
paths[TB_DP_AUX_PATH_OUT]->hops[0].in_hop_index,
paths[TB_DP_AUX_PATH_IN]->hops[last].next_hop_index);
tb_dp_port_set_hops(tunnel->dst_port,
paths[TB_DP_VIDEO_PATH_OUT]->hops[last].next_hop_index,
paths[TB_DP_AUX_PATH_IN]->hops[0].in_hop_index,
paths[TB_DP_AUX_PATH_OUT]->hops[last].next_hop_index);
} else {
tb_dp_port_hpd_clear(tunnel->src_port);
tb_dp_port_set_hops(tunnel->src_port, 0, 0, 0);
if (tb_port_is_dpout(tunnel->dst_port))
tb_dp_port_set_hops(tunnel->dst_port, 0, 0, 0);
}
ret = tb_dp_port_enable(tunnel->src_port, active);
if (ret)
return ret;
if (tb_port_is_dpout(tunnel->dst_port))
return tb_dp_port_enable(tunnel->dst_port, active);
return 0;
}
static int tb_dp_consumed_bandwidth(struct tb_tunnel *tunnel)
{
struct tb_port *in = tunnel->src_port;
const struct tb_switch *sw = in->sw;
u32 val, rate = 0, lanes = 0;
int ret;
if (tb_switch_is_titan_ridge(sw)) {
int timeout = 10;
/*
* Wait for DPRX done. Normally it should be already set
* for active tunnel.
*/
do {
ret = tb_port_read(in, &val, TB_CFG_PORT,
in->cap_adap + DP_COMMON_CAP, 1);
if (ret)
return ret;
if (val & DP_COMMON_CAP_DPRX_DONE) {
rate = tb_dp_cap_get_rate(val);
lanes = tb_dp_cap_get_lanes(val);
break;
}
msleep(250);
} while (timeout--);
if (!timeout)
return -ETIMEDOUT;
} else if (sw->generation >= 2) {
/*
* Read from the copied remote cap so that we take into
* account if capabilities were reduced during exchange.
*/
ret = tb_port_read(in, &val, TB_CFG_PORT,
in->cap_adap + DP_REMOTE_CAP, 1);
if (ret)
return ret;
rate = tb_dp_cap_get_rate(val);
lanes = tb_dp_cap_get_lanes(val);
} else {
/* No bandwidth management for legacy devices */
return 0;
}
return tb_dp_bandwidth(rate, lanes);
}
static void tb_dp_init_aux_path(struct tb_path *path)
{
int i;
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 = 2;
path->weight = 1;
for (i = 0; i < path->path_length; i++)
path->hops[i].initial_credits = 1;
}
static void tb_dp_init_video_path(struct tb_path *path, bool discover)
{
u32 nfc_credits = path->hops[0].in_port->config.nfc_credits;
path->egress_fc_enable = TB_PATH_NONE;
path->egress_shared_buffer = TB_PATH_NONE;
path->ingress_fc_enable = TB_PATH_NONE;
path->ingress_shared_buffer = TB_PATH_NONE;
path->priority = 1;
path->weight = 1;
if (discover) {
path->nfc_credits = nfc_credits & ADP_CS_4_NFC_BUFFERS_MASK;
} else {
u32 max_credits;
max_credits = (nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
ADP_CS_4_TOTAL_BUFFERS_SHIFT;
/* Leave some credits for AUX path */
path->nfc_credits = min(max_credits - 2, 12U);
}
}
/**
* tb_tunnel_discover_dp() - Discover existing Display Port tunnels
* @tb: Pointer to the domain structure
* @in: DP in adapter
*
* If @in adapter is active, follows the tunnel to the DP out adapter
* and back. Returns the discovered tunnel or %NULL if there was no
* tunnel.
*
* Return: DP tunnel or %NULL if no tunnel found.
*/
struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in)
{
struct tb_tunnel *tunnel;
struct tb_port *port;
struct tb_path *path;
if (!tb_dp_port_is_enabled(in))
return NULL;
tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
if (!tunnel)
return NULL;
tunnel->init = tb_dp_xchg_caps;
tunnel->activate = tb_dp_activate;
tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
tunnel->src_port = in;
path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1,
&tunnel->dst_port, "Video");
if (!path) {
/* Just disable the DP IN port */
tb_dp_port_enable(in, false);
goto err_free;
}
tunnel->paths[TB_DP_VIDEO_PATH_OUT] = path;
tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT], true);
path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX");
if (!path)
goto err_deactivate;
tunnel->paths[TB_DP_AUX_PATH_OUT] = path;
tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT]);
path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID,
&port, "AUX RX");
if (!path)
goto err_deactivate;
tunnel->paths[TB_DP_AUX_PATH_IN] = path;
tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_IN]);
/* Validate that the tunnel is complete */
if (!tb_port_is_dpout(tunnel->dst_port)) {
tb_port_warn(in, "path does not end on a DP adapter, cleaning up\n");
goto err_deactivate;
}
if (!tb_dp_port_is_enabled(tunnel->dst_port))
goto err_deactivate;
if (!tb_dp_port_hpd_is_active(tunnel->dst_port))
goto err_deactivate;
if (port != tunnel->src_port) {
tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
goto err_deactivate;
}
tb_tunnel_dbg(tunnel, "discovered\n");
return tunnel;
err_deactivate:
tb_tunnel_deactivate(tunnel);
err_free:
tb_tunnel_free(tunnel);
return NULL;
}
/**
* tb_tunnel_alloc_dp() - allocate a Display Port tunnel
* @tb: Pointer to the domain structure
* @in: DP in adapter port
* @out: DP out adapter port
* @max_bw: Maximum available bandwidth for the DP tunnel (%0 if not limited)
*
* Allocates a tunnel between @in and @out that is capable of tunneling
* Display Port traffic.
*
* Return: Returns a tb_tunnel on success or NULL on failure.
*/
struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
struct tb_port *out, int max_bw)
{
struct tb_tunnel *tunnel;
struct tb_path **paths;
struct tb_path *path;
if (WARN_ON(!in->cap_adap || !out->cap_adap))
return NULL;
tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
if (!tunnel)
return NULL;
tunnel->init = tb_dp_xchg_caps;
tunnel->activate = tb_dp_activate;
tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
tunnel->src_port = in;
tunnel->dst_port = out;
tunnel->max_bw = max_bw;
paths = tunnel->paths;
path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID,
1, "Video");
if (!path)
goto err_free;
tb_dp_init_video_path(path, false);
paths[TB_DP_VIDEO_PATH_OUT] = path;
path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out,
TB_DP_AUX_TX_HOPID, 1, "AUX TX");
if (!path)
goto err_free;
tb_dp_init_aux_path(path);
paths[TB_DP_AUX_PATH_OUT] = path;
path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in,
TB_DP_AUX_RX_HOPID, 1, "AUX RX");
if (!path)
goto err_free;
tb_dp_init_aux_path(path);
paths[TB_DP_AUX_PATH_IN] = path;
return tunnel;
err_free:
tb_tunnel_free(tunnel);
return NULL;
}
static u32 tb_dma_credits(struct tb_port *nhi)
{
u32 max_credits;
max_credits = (nhi->config.nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
ADP_CS_4_TOTAL_BUFFERS_SHIFT;
return min(max_credits, 13U);
}
static int tb_dma_activate(struct tb_tunnel *tunnel, bool active)
{
struct tb_port *nhi = tunnel->src_port;
u32 credits;
credits = active ? tb_dma_credits(nhi) : 0;
return tb_port_set_initial_credits(nhi, credits);
}
static void tb_dma_init_path(struct tb_path *path, unsigned int isb,
unsigned int efc, u32 credits)
{
int i;
path->egress_fc_enable = efc;
path->ingress_fc_enable = TB_PATH_ALL;
path->egress_shared_buffer = TB_PATH_NONE;
path->ingress_shared_buffer = isb;
path->priority = 5;
path->weight = 1;
path->clear_fc = true;
for (i = 0; i < path->path_length; i++)
path->hops[i].initial_credits = credits;
}
/**
* tb_tunnel_alloc_dma() - allocate a DMA tunnel
* @tb: Pointer to the domain structure
* @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
* @transmit_path: HopID used for transmitting packets
* @receive_ring: NHI ring number used to receive packets from the
* other domain
* @reveive_path: HopID used for receiving packets
*
* Return: Returns a tb_tunnel on success or NULL on failure.
*/
struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
struct tb_port *dst, int transmit_ring,
int transmit_path, int receive_ring,
int receive_path)
{
struct tb_tunnel *tunnel;
struct tb_path *path;
u32 credits;
tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_DMA);
if (!tunnel)
return NULL;
tunnel->activate = tb_dma_activate;
tunnel->src_port = nhi;
tunnel->dst_port = dst;
credits = tb_dma_credits(nhi);
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;
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;
return tunnel;
}
/**
* tb_tunnel_free() - free a tunnel
* @tunnel: Tunnel to be freed
*
* Frees a tunnel. The tunnel does not need to be deactivated.
*/
void tb_tunnel_free(struct tb_tunnel *tunnel)
{
int i;
if (!tunnel)
return;
for (i = 0; i < tunnel->npaths; i++) {
if (tunnel->paths[i])
tb_path_free(tunnel->paths[i]);
}
kfree(tunnel->paths);
kfree(tunnel);
}
/**
* tb_tunnel_is_invalid - check whether an activated path is still valid
* @tunnel: Tunnel to check
*/
bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel)
{
int i;
for (i = 0; i < tunnel->npaths; i++) {
WARN_ON(!tunnel->paths[i]->activated);
if (tb_path_is_invalid(tunnel->paths[i]))
return true;
}
return false;
}
/**
* tb_tunnel_restart() - activate a tunnel after a hardware reset
* @tunnel: Tunnel to restart
*
* Return: 0 on success and negative errno in case if failure
*/
int tb_tunnel_restart(struct tb_tunnel *tunnel)
{
int res, i;
tb_tunnel_dbg(tunnel, "activating\n");
/*
* Make sure all paths are properly disabled before enabling
* them again.
*/
for (i = 0; i < tunnel->npaths; i++) {
if (tunnel->paths[i]->activated) {
tb_path_deactivate(tunnel->paths[i]);
tunnel->paths[i]->activated = false;
}
}
if (tunnel->init) {
res = tunnel->init(tunnel);
if (res)
return res;
}
for (i = 0; i < tunnel->npaths; i++) {
res = tb_path_activate(tunnel->paths[i]);
if (res)
goto err;
}
if (tunnel->activate) {
res = tunnel->activate(tunnel, true);
if (res)
goto err;
}
return 0;
err:
tb_tunnel_warn(tunnel, "activation failed\n");
tb_tunnel_deactivate(tunnel);
return res;
}
/**
* tb_tunnel_activate() - activate a tunnel
* @tunnel: Tunnel to activate
*
* Return: Returns 0 on success or an error code on failure.
*/
int tb_tunnel_activate(struct tb_tunnel *tunnel)
{
int i;
for (i = 0; i < tunnel->npaths; i++) {
if (tunnel->paths[i]->activated) {
tb_tunnel_WARN(tunnel,
"trying to activate an already activated tunnel\n");
return -EINVAL;
}
}
return tb_tunnel_restart(tunnel);
}
/**
* tb_tunnel_deactivate() - deactivate a tunnel
* @tunnel: Tunnel to deactivate
*/
void tb_tunnel_deactivate(struct tb_tunnel *tunnel)
{
int i;
tb_tunnel_dbg(tunnel, "deactivating\n");
if (tunnel->activate)
tunnel->activate(tunnel, false);
for (i = 0; i < tunnel->npaths; i++) {
if (tunnel->paths[i] && tunnel->paths[i]->activated)
tb_path_deactivate(tunnel->paths[i]);
}
}
/**
* tb_tunnel_switch_on_path() - Does the tunnel go through switch
* @tunnel: Tunnel to check
* @sw: Switch to check
*
* Returns true if @tunnel goes through @sw (direction does not matter),
* false otherwise.
*/
bool tb_tunnel_switch_on_path(const struct tb_tunnel *tunnel,
const struct tb_switch *sw)
{
int i;
for (i = 0; i < tunnel->npaths; i++) {
if (!tunnel->paths[i])
continue;
if (tb_path_switch_on_path(tunnel->paths[i], sw))
return true;
}
return false;
}
static bool tb_tunnel_is_active(const struct tb_tunnel *tunnel)
{
int i;
for (i = 0; i < tunnel->npaths; i++) {
if (!tunnel->paths[i])
return false;
if (!tunnel->paths[i]->activated)
return false;
}
return true;
}
/**
* tb_tunnel_consumed_bandwidth() - Return bandwidth consumed by the tunnel
* @tunnel: Tunnel to check
*
* Returns bandwidth currently consumed by @tunnel and %0 if the @tunnel
* is not active or does consume bandwidth.
*/
int tb_tunnel_consumed_bandwidth(struct tb_tunnel *tunnel)
{
if (!tb_tunnel_is_active(tunnel))
return 0;
if (tunnel->consumed_bandwidth) {
int ret = tunnel->consumed_bandwidth(tunnel);
tb_tunnel_dbg(tunnel, "consumed bandwidth %d Mb/s\n", ret);
return ret;
}
return 0;
}