// SPDX-License-Identifier: MIT
/*
* Copyright © 2023 Intel Corporation
*/
#include <linux/ref_tracker.h>
#include <linux/types.h>
#include <drm/drm_atomic_state_helper.h>
#include <drm/drm_atomic.h>
#include <drm/drm_print.h>
#include <drm/display/drm_dp.h>
#include <drm/display/drm_dp_helper.h>
#include <drm/display/drm_dp_tunnel.h>
#define to_group(__private_obj) \
container_of(__private_obj, struct drm_dp_tunnel_group, base)
#define to_group_state(__private_state) \
container_of(__private_state, struct drm_dp_tunnel_group_state, base)
#define is_dp_tunnel_private_obj(__obj) \
((__obj)->funcs == &tunnel_group_funcs)
#define for_each_new_group_in_state(__state, __new_group_state, __i) \
for ((__i) = 0; \
(__i) < (__state)->num_private_objs; \
(__i)++) \
for_each_if ((__state)->private_objs[__i].ptr && \
is_dp_tunnel_private_obj((__state)->private_objs[__i].ptr) && \
((__new_group_state) = \
to_group_state((__state)->private_objs[__i].new_state), 1))
#define for_each_old_group_in_state(__state, __old_group_state, __i) \
for ((__i) = 0; \
(__i) < (__state)->num_private_objs; \
(__i)++) \
for_each_if ((__state)->private_objs[__i].ptr && \
is_dp_tunnel_private_obj((__state)->private_objs[__i].ptr) && \
((__old_group_state) = \
to_group_state((__state)->private_objs[__i].old_state), 1))
#define for_each_tunnel_in_group(__group, __tunnel) \
list_for_each_entry(__tunnel, &(__group)->tunnels, node)
#define for_each_tunnel_state(__group_state, __tunnel_state) \
list_for_each_entry(__tunnel_state, &(__group_state)->tunnel_states, node)
#define for_each_tunnel_state_safe(__group_state, __tunnel_state, __tunnel_state_tmp) \
list_for_each_entry_safe(__tunnel_state, __tunnel_state_tmp, \
&(__group_state)->tunnel_states, node)
#define kbytes_to_mbits(__kbytes) \
DIV_ROUND_UP((__kbytes) * 8, 1000)
#define DPTUN_BW_ARG(__bw) ((__bw) < 0 ? (__bw) : kbytes_to_mbits(__bw))
#define __tun_prn(__tunnel, __level, __type, __fmt, ...) \
drm_##__level##__type((__tunnel)->group->mgr->dev, \
"[DPTUN %s][%s] " __fmt, \
drm_dp_tunnel_name(__tunnel), \
(__tunnel)->aux->name, ## \
__VA_ARGS__)
#define tun_dbg(__tunnel, __fmt, ...) \
__tun_prn(__tunnel, dbg, _kms, __fmt, ## __VA_ARGS__)
#define tun_dbg_stat(__tunnel, __err, __fmt, ...) do { \
if (__err) \
__tun_prn(__tunnel, dbg, _kms, __fmt " (Failed, err: %pe)\n", \
## __VA_ARGS__, ERR_PTR(__err)); \
else \
__tun_prn(__tunnel, dbg, _kms, __fmt " (Ok)\n", \
## __VA_ARGS__); \
} while (0)
#define tun_dbg_atomic(__tunnel, __fmt, ...) \
__tun_prn(__tunnel, dbg, _atomic, __fmt, ## __VA_ARGS__)
#define tun_grp_dbg(__group, __fmt, ...) \
drm_dbg_kms((__group)->mgr->dev, \
"[DPTUN %s] " __fmt, \
drm_dp_tunnel_group_name(__group), ## \
__VA_ARGS__)
#define DP_TUNNELING_BASE DP_TUNNELING_OUI
#define __DPTUN_REG_RANGE(__start, __size) \
GENMASK_ULL((__start) + (__size) - 1, (__start))
#define DPTUN_REG_RANGE(__addr, __size) \
__DPTUN_REG_RANGE((__addr) - DP_TUNNELING_BASE, (__size))
#define DPTUN_REG(__addr) DPTUN_REG_RANGE(__addr, 1)
#define DPTUN_INFO_REG_MASK ( \
DPTUN_REG_RANGE(DP_TUNNELING_OUI, DP_TUNNELING_OUI_BYTES) | \
DPTUN_REG_RANGE(DP_TUNNELING_DEV_ID, DP_TUNNELING_DEV_ID_BYTES) | \
DPTUN_REG(DP_TUNNELING_HW_REV) | \
DPTUN_REG(DP_TUNNELING_SW_REV_MAJOR) | \
DPTUN_REG(DP_TUNNELING_SW_REV_MINOR) | \
DPTUN_REG(DP_TUNNELING_CAPABILITIES) | \
DPTUN_REG(DP_IN_ADAPTER_INFO) | \
DPTUN_REG(DP_USB4_DRIVER_ID) | \
DPTUN_REG(DP_USB4_DRIVER_BW_CAPABILITY) | \
DPTUN_REG(DP_IN_ADAPTER_TUNNEL_INFORMATION) | \
DPTUN_REG(DP_BW_GRANULARITY) | \
DPTUN_REG(DP_ESTIMATED_BW) | \
DPTUN_REG(DP_ALLOCATED_BW) | \
DPTUN_REG(DP_TUNNELING_MAX_LINK_RATE) | \
DPTUN_REG(DP_TUNNELING_MAX_LANE_COUNT) | \
DPTUN_REG(DP_DPTX_BW_ALLOCATION_MODE_CONTROL))
static const DECLARE_BITMAP(dptun_info_regs, 64) = {
DPTUN_INFO_REG_MASK & -1UL,
#if BITS_PER_LONG == 32
DPTUN_INFO_REG_MASK >> 32,
#endif
};
struct drm_dp_tunnel_regs {
u8 buf[HWEIGHT64(DPTUN_INFO_REG_MASK)];
};
struct drm_dp_tunnel_group;
struct drm_dp_tunnel {
struct drm_dp_tunnel_group *group;
struct list_head node;
struct kref kref;
struct ref_tracker *tracker;
struct drm_dp_aux *aux;
char name[8];
int bw_granularity;
int estimated_bw;
int allocated_bw;
int max_dprx_rate;
u8 max_dprx_lane_count;
u8 adapter_id;
bool bw_alloc_supported:1;
bool bw_alloc_enabled:1;
bool has_io_error:1;
bool destroyed:1;
};
struct drm_dp_tunnel_group_state;
struct drm_dp_tunnel_state {
struct drm_dp_tunnel_group_state *group_state;
struct drm_dp_tunnel_ref tunnel_ref;
struct list_head node;
u32 stream_mask;
int *stream_bw;
};
struct drm_dp_tunnel_group_state {
struct drm_private_state base;
struct list_head tunnel_states;
};
struct drm_dp_tunnel_group {
struct drm_private_obj base;
struct drm_dp_tunnel_mgr *mgr;
struct list_head tunnels;
/* available BW including the allocated_bw of all tunnels in the group */
int available_bw;
u8 drv_group_id;
char name[8];
bool active:1;
};
struct drm_dp_tunnel_mgr {
struct drm_device *dev;
int group_count;
struct drm_dp_tunnel_group *groups;
wait_queue_head_t bw_req_queue;
#ifdef CONFIG_DRM_DISPLAY_DP_TUNNEL_STATE_DEBUG
struct ref_tracker_dir ref_tracker;
#endif
};
/*
* The following helpers provide a way to read out the tunneling DPCD
* registers with a minimal amount of AUX transfers (1 transfer per contiguous
* range, as permitted by the 16 byte per transfer AUX limit), not accessing
* other registers to avoid any read side-effects.
*/
static int next_reg_area(int *offset)
{
*offset = find_next_bit(dptun_info_regs, 64, *offset);
return find_next_zero_bit(dptun_info_regs, 64, *offset + 1) - *offset;
}
#define tunnel_reg_ptr(__regs, __address) ({ \
WARN_ON(!test_bit((__address) - DP_TUNNELING_BASE, dptun_info_regs)); \
&(__regs)->buf[bitmap_weight(dptun_info_regs, (__address) - DP_TUNNELING_BASE)]; \
})
static int read_tunnel_regs(struct drm_dp_aux *aux, struct drm_dp_tunnel_regs *regs)
{
int offset = 0;
int len;
while ((len = next_reg_area(&offset))) {
int address = DP_TUNNELING_BASE + offset;
if (drm_dp_dpcd_read(aux, address, tunnel_reg_ptr(regs, address), len) < 0)
return -EIO;
offset += len;
}
return 0;
}
static u8 tunnel_reg(const struct drm_dp_tunnel_regs *regs, int address)
{
return *tunnel_reg_ptr(regs, address);
}
static u8 tunnel_reg_drv_group_id(const struct drm_dp_tunnel_regs *regs)
{
u8 drv_id = tunnel_reg(regs, DP_USB4_DRIVER_ID) & DP_USB4_DRIVER_ID_MASK;
u8 group_id = tunnel_reg(regs, DP_IN_ADAPTER_TUNNEL_INFORMATION) & DP_GROUP_ID_MASK;
if (!group_id)
return 0;
return (drv_id << DP_GROUP_ID_BITS) | group_id;
}
/* Return granularity in kB/s units */
static int tunnel_reg_bw_granularity(const struct drm_dp_tunnel_regs *regs)
{
int gr = tunnel_reg(regs, DP_BW_GRANULARITY) & DP_BW_GRANULARITY_MASK;
if (gr > 2)
return -1;
return (250000 << gr) / 8;
}
static int tunnel_reg_max_dprx_rate(const struct drm_dp_tunnel_regs *regs)
{
u8 bw_code = tunnel_reg(regs, DP_TUNNELING_MAX_LINK_RATE);
return drm_dp_bw_code_to_link_rate(bw_code);
}
static int tunnel_reg_max_dprx_lane_count(const struct drm_dp_tunnel_regs *regs)
{
return tunnel_reg(regs, DP_TUNNELING_MAX_LANE_COUNT) &
DP_TUNNELING_MAX_LANE_COUNT_MASK;
}
static bool tunnel_reg_bw_alloc_supported(const struct drm_dp_tunnel_regs *regs)
{
u8 cap_mask = DP_TUNNELING_SUPPORT | DP_IN_BW_ALLOCATION_MODE_SUPPORT;
if ((tunnel_reg(regs, DP_TUNNELING_CAPABILITIES) & cap_mask) != cap_mask)
return false;
return tunnel_reg(regs, DP_USB4_DRIVER_BW_CAPABILITY) &
DP_USB4_DRIVER_BW_ALLOCATION_MODE_SUPPORT;
}
static bool tunnel_reg_bw_alloc_enabled(const struct drm_dp_tunnel_regs *regs)
{
return tunnel_reg(regs, DP_DPTX_BW_ALLOCATION_MODE_CONTROL) &
DP_DISPLAY_DRIVER_BW_ALLOCATION_MODE_ENABLE;
}
static u8 tunnel_group_drv_id(u8 drv_group_id)
{
return drv_group_id >> DP_GROUP_ID_BITS;
}
static u8 tunnel_group_id(u8 drv_group_id)
{
return drv_group_id & DP_GROUP_ID_MASK;
}
const char *drm_dp_tunnel_name(const struct drm_dp_tunnel *tunnel)
{
return tunnel->name;
}
EXPORT_SYMBOL(drm_dp_tunnel_name);
static const char *drm_dp_tunnel_group_name(const struct drm_dp_tunnel_group *group)
{
return group->name;
}
static struct drm_dp_tunnel_group *
lookup_or_alloc_group(struct drm_dp_tunnel_mgr *mgr, u8 drv_group_id)
{
struct drm_dp_tunnel_group *group = NULL;
int i;
for (i = 0; i < mgr->group_count; i++) {
/*
* A tunnel group with 0 group ID shouldn't have more than one
* tunnels.
*/
if (tunnel_group_id(drv_group_id) &&
mgr->groups[i].drv_group_id == drv_group_id)
return &mgr->groups[i];
if (!group && !mgr->groups[i].active)
group = &mgr->groups[i];
}
if (!group) {
drm_dbg_kms(mgr->dev,
"DPTUN: Can't allocate more tunnel groups\n");
return NULL;
}
group->drv_group_id = drv_group_id;
group->active = true;
/*
* The group name format here and elsewhere: Driver-ID:Group-ID:*
* (* standing for all DP-Adapters/tunnels in the group).
*/
snprintf(group->name, sizeof(group->name), "%d:%d:*",
tunnel_group_drv_id(drv_group_id) & ((1 << DP_GROUP_ID_BITS) - 1),
tunnel_group_id(drv_group_id) & ((1 << DP_USB4_DRIVER_ID_BITS) - 1));
return group;
}
static void free_group(struct drm_dp_tunnel_group *group)
{
struct drm_dp_tunnel_mgr *mgr = group->mgr;
if (drm_WARN_ON(mgr->dev, !list_empty(&group->tunnels)))
return;
group->drv_group_id = 0;
group->available_bw = -1;
group->active = false;
}
static struct drm_dp_tunnel *
tunnel_get(struct drm_dp_tunnel *tunnel)
{
kref_get(&tunnel->kref);
return tunnel;
}
static void free_tunnel(struct kref *kref)
{
struct drm_dp_tunnel *tunnel = container_of(kref, typeof(*tunnel), kref);
struct drm_dp_tunnel_group *group = tunnel->group;
list_del(&tunnel->node);
if (list_empty(&group->tunnels))
free_group(group);
kfree(tunnel);
}
static void tunnel_put(struct drm_dp_tunnel *tunnel)
{
kref_put(&tunnel->kref, free_tunnel);
}
#ifdef CONFIG_DRM_DISPLAY_DP_TUNNEL_STATE_DEBUG
static void track_tunnel_ref(struct drm_dp_tunnel *tunnel,
struct ref_tracker **tracker)
{
ref_tracker_alloc(&tunnel->group->mgr->ref_tracker,
tracker, GFP_KERNEL);
}
static void untrack_tunnel_ref(struct drm_dp_tunnel *tunnel,
struct ref_tracker **tracker)
{
ref_tracker_free(&tunnel->group->mgr->ref_tracker,
tracker);
}
#else
static void track_tunnel_ref(struct drm_dp_tunnel *tunnel,
struct ref_tracker **tracker)
{
}
static void untrack_tunnel_ref(struct drm_dp_tunnel *tunnel,
struct ref_tracker **tracker)
{
}
#endif
/**
* drm_dp_tunnel_get - Get a reference for a DP tunnel
* @tunnel: Tunnel object
* @tracker: Debug tracker for the reference
*
* Get a reference for @tunnel, along with a debug tracker to help locating
* the source of a reference leak/double reference put etc. issue.
*
* The reference must be dropped after use calling drm_dp_tunnel_put()
* passing @tunnel and *@tracker returned from here.
*
* Returns @tunnel - as a convenience - along with *@tracker.
*/
struct drm_dp_tunnel *
drm_dp_tunnel_get(struct drm_dp_tunnel *tunnel,
struct ref_tracker **tracker)
{
track_tunnel_ref(tunnel, tracker);
return tunnel_get(tunnel);
}
EXPORT_SYMBOL(drm_dp_tunnel_get);
/**
* drm_dp_tunnel_put - Put a reference for a DP tunnel
* @tunnel: Tunnel object
* @tracker: Debug tracker for the reference
*
* Put a reference for @tunnel along with its debug *@tracker, which
* was obtained with drm_dp_tunnel_get().
*/
void drm_dp_tunnel_put(struct drm_dp_tunnel *tunnel,
struct ref_tracker **tracker)
{
untrack_tunnel_ref(tunnel, tracker);
tunnel_put(tunnel);
}
EXPORT_SYMBOL(drm_dp_tunnel_put);
static bool add_tunnel_to_group(struct drm_dp_tunnel_mgr *mgr,
u8 drv_group_id,
struct drm_dp_tunnel *tunnel)
{
struct drm_dp_tunnel_group *group;
group = lookup_or_alloc_group(mgr, drv_group_id);
if (!group)
return false;
tunnel->group = group;
list_add(&tunnel->node, &group->tunnels);
return true;
}
static struct drm_dp_tunnel *
create_tunnel(struct drm_dp_tunnel_mgr *mgr,
struct drm_dp_aux *aux,
const struct drm_dp_tunnel_regs *regs)
{
u8 drv_group_id = tunnel_reg_drv_group_id(regs);
struct drm_dp_tunnel *tunnel;
tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
if (!tunnel)
return NULL;
INIT_LIST_HEAD(&tunnel->node);
kref_init(&tunnel->kref);
tunnel->aux = aux;
tunnel->adapter_id = tunnel_reg(regs, DP_IN_ADAPTER_INFO) & DP_IN_ADAPTER_NUMBER_MASK;
snprintf(tunnel->name, sizeof(tunnel->name), "%d:%d:%d",
tunnel_group_drv_id(drv_group_id) & ((1 << DP_GROUP_ID_BITS) - 1),
tunnel_group_id(drv_group_id) & ((1 << DP_USB4_DRIVER_ID_BITS) - 1),
tunnel->adapter_id & ((1 << DP_IN_ADAPTER_NUMBER_BITS) - 1));
tunnel->bw_granularity = tunnel_reg_bw_granularity(regs);
tunnel->allocated_bw = tunnel_reg(regs, DP_ALLOCATED_BW) *
tunnel->bw_granularity;
/*
* An initial allocated BW of 0 indicates an undefined state: the
* actual allocation is determined by the TBT CM, usually following a
* legacy allocation policy (based on the max DPRX caps). From the
* driver's POV the state becomes defined only after the first
* allocation request.
*/
if (!tunnel->allocated_bw)
tunnel->allocated_bw = -1;
tunnel->bw_alloc_supported = tunnel_reg_bw_alloc_supported(regs);
tunnel->bw_alloc_enabled = tunnel_reg_bw_alloc_enabled(regs);
if (!add_tunnel_to_group(mgr, drv_group_id, tunnel)) {
kfree(tunnel);
return NULL;
}
track_tunnel_ref(tunnel, &tunnel->tracker);
return tunnel;
}
static void destroy_tunnel(struct drm_dp_tunnel *tunnel)
{
untrack_tunnel_ref(tunnel, &tunnel->tracker);
tunnel_put(tunnel);
}
/**
* drm_dp_tunnel_set_io_error - Set the IO error flag for a DP tunnel
* @tunnel: Tunnel object
*
* Set the IO error flag for @tunnel. Drivers can call this function upon
* detecting a failure that affects the tunnel functionality, for instance
* after a DP AUX transfer failure on the port @tunnel is connected to.
*
* This disables further management of @tunnel, including any related
* AUX accesses for tunneling DPCD registers, returning error to the
* initiators of these. The driver is supposed to drop this tunnel and -
* optionally - recreate it.
*/
void drm_dp_tunnel_set_io_error(struct drm_dp_tunnel *tunnel)
{
tunnel->has_io_error = true;
}
EXPORT_SYMBOL(drm_dp_tunnel_set_io_error);
#define SKIP_DPRX_CAPS_CHECK BIT(0)
#define ALLOW_ALLOCATED_BW_CHANGE BIT(1)
static bool tunnel_regs_are_valid(struct drm_dp_tunnel_mgr *mgr,
const struct drm_dp_tunnel_regs *regs,
unsigned int flags)
{
u8 drv_group_id = tunnel_reg_drv_group_id(regs);
bool check_dprx = !(flags & SKIP_DPRX_CAPS_CHECK);
bool ret = true;
if (!tunnel_reg_bw_alloc_supported(regs)) {
if (tunnel_group_id(drv_group_id)) {
drm_dbg_kms(mgr->dev,
"DPTUN: A non-zero group ID is only allowed with BWA support\n");
ret = false;
}
if (tunnel_reg(regs, DP_ALLOCATED_BW)) {
drm_dbg_kms(mgr->dev,
"DPTUN: BW is allocated without BWA support\n");
ret = false;
}
return ret;
}
if (!tunnel_group_id(drv_group_id)) {
drm_dbg_kms(mgr->dev,
"DPTUN: BWA support requires a non-zero group ID\n");
ret = false;
}
if (check_dprx && hweight8(tunnel_reg_max_dprx_lane_count(regs)) != 1) {
drm_dbg_kms(mgr->dev,
"DPTUN: Invalid DPRX lane count: %d\n",
tunnel_reg_max_dprx_lane_count(regs));
ret = false;
}
if (check_dprx && !tunnel_reg_max_dprx_rate(regs)) {
drm_dbg_kms(mgr->dev,
"DPTUN: DPRX rate is 0\n");
ret = false;
}
if (tunnel_reg_bw_granularity(regs) < 0) {
drm_dbg_kms(mgr->dev,
"DPTUN: Invalid BW granularity\n");
ret = false;
}
if (tunnel_reg(regs, DP_ALLOCATED_BW) > tunnel_reg(regs, DP_ESTIMATED_BW)) {
drm_dbg_kms(mgr->dev,
"DPTUN: Allocated BW %d > estimated BW %d Mb/s\n",
DPTUN_BW_ARG(tunnel_reg(regs, DP_ALLOCATED_BW) *
tunnel_reg_bw_granularity(regs)),
DPTUN_BW_ARG(tunnel_reg(regs, DP_ESTIMATED_BW) *
tunnel_reg_bw_granularity(regs)));
ret = false;
}
return ret;
}
static int tunnel_allocated_bw(const struct drm_dp_tunnel *tunnel)
{
return max(tunnel->allocated_bw, 0);
}
static bool tunnel_info_changes_are_valid(struct drm_dp_tunnel *tunnel,
const struct drm_dp_tunnel_regs *regs,
unsigned int flags)
{
u8 new_drv_group_id = tunnel_reg_drv_group_id(regs);
bool ret = true;
if (tunnel->bw_alloc_supported != tunnel_reg_bw_alloc_supported(regs)) {
tun_dbg(tunnel,
"BW alloc support has changed %s -> %s\n",
str_yes_no(tunnel->bw_alloc_supported),
str_yes_no(tunnel_reg_bw_alloc_supported(regs)));
ret = false;
}
if (tunnel->group->drv_group_id != new_drv_group_id) {
tun_dbg(tunnel,
"Driver/group ID has changed %d:%d:* -> %d:%d:*\n",
tunnel_group_drv_id(tunnel->group->drv_group_id),
tunnel_group_id(tunnel->group->drv_group_id),
tunnel_group_drv_id(new_drv_group_id),
tunnel_group_id(new_drv_group_id));
ret = false;
}
if (!tunnel->bw_alloc_supported)
return ret;
if (tunnel->bw_granularity != tunnel_reg_bw_granularity(regs)) {
tun_dbg(tunnel,
"BW granularity has changed: %d -> %d Mb/s\n",
DPTUN_BW_ARG(tunnel->bw_granularity),
DPTUN_BW_ARG(tunnel_reg_bw_granularity(regs)));
ret = false;
}
/*
* On some devices at least the BW alloc mode enabled status is always
* reported as 0, so skip checking that here.
*/
if (!(flags & ALLOW_ALLOCATED_BW_CHANGE) &&
tunnel_allocated_bw(tunnel) !=
tunnel_reg(regs, DP_ALLOCATED_BW) * tunnel->bw_granularity) {
tun_dbg(tunnel,
"Allocated BW has changed: %d -> %d Mb/s\n",
DPTUN_BW_ARG(tunnel->allocated_bw),
DPTUN_BW_ARG(tunnel_reg(regs, DP_ALLOCATED_BW) * tunnel->bw_granularity));
ret = false;
}
return ret;
}
static int
read_and_verify_tunnel_regs(struct drm_dp_tunnel *tunnel,
struct drm_dp_tunnel_regs *regs,
unsigned int flags)
{
int err;
err = read_tunnel_regs(tunnel->aux, regs);
if (err < 0) {
drm_dp_tunnel_set_io_error(tunnel);
return err;
}
if (!tunnel_regs_are_valid(tunnel->group->mgr, regs, flags))
return -EINVAL;
if (!tunnel_info_changes_are_valid(tunnel, regs, flags))
return -EINVAL;
return 0;
}
static bool update_dprx_caps(struct drm_dp_tunnel *tunnel, const struct drm_dp_tunnel_regs *regs)
{
bool changed = false;
if (tunnel_reg_max_dprx_rate(regs) != tunnel->max_dprx_rate) {
tunnel->max_dprx_rate = tunnel_reg_max_dprx_rate(regs);
changed = true;
}
if (tunnel_reg_max_dprx_lane_count(regs) != tunnel->max_dprx_lane_count) {
tunnel->max_dprx_lane_count = tunnel_reg_max_dprx_lane_count(regs);
changed = true;
}
return changed;
}
static int dev_id_len(const u8 *dev_id, int max_len)
{
while (max_len && dev_id[max_len - 1] == '\0')
max_len--;
return max_len;
}
static int get_max_dprx_bw(const struct drm_dp_tunnel *tunnel)
{
int max_dprx_bw = drm_dp_max_dprx_data_rate(tunnel->max_dprx_rate,
tunnel->max_dprx_lane_count);
/*
* A BW request of roundup(max_dprx_bw, tunnel->bw_granularity) results in
* an allocation of max_dprx_bw. A BW request above this rounded-up
* value will fail.
*/
return min(roundup(max_dprx_bw, tunnel->bw_granularity),
MAX_DP_REQUEST_BW * tunnel->bw_granularity);
}
static int get_max_tunnel_bw(const struct drm_dp_tunnel *tunnel)
{
return min(get_max_dprx_bw(tunnel), tunnel->group->available_bw);
}
/**
* drm_dp_tunnel_detect - Detect DP tunnel on the link
* @mgr: Tunnel manager
* @aux: DP AUX on which the tunnel will be detected
*
* Detect if there is any DP tunnel on the link and add it to the tunnel
* group's tunnel list.
*
* Returns a pointer to a tunnel on success, or an ERR_PTR() error on
* failure.
*/
struct drm_dp_tunnel *
drm_dp_tunnel_detect(struct drm_dp_tunnel_mgr *mgr,
struct drm_dp_aux *aux)
{
struct drm_dp_tunnel_regs regs;
struct drm_dp_tunnel *tunnel;
int err;
err = read_tunnel_regs(aux, ®s);
if (err)
return ERR_PTR(err);
if (!(tunnel_reg(®s, DP_TUNNELING_CAPABILITIES) &
DP_TUNNELING_SUPPORT))
return ERR_PTR(-ENODEV);
/* The DPRX caps are valid only after enabling BW alloc mode. */
if (!tunnel_regs_are_valid(mgr, ®s, SKIP_DPRX_CAPS_CHECK))
return ERR_PTR(-EINVAL);
tunnel = create_tunnel(mgr, aux, ®s);
if (!tunnel)
return ERR_PTR(-ENOMEM);
tun_dbg(tunnel,
"OUI:%*phD DevID:%*pE Rev-HW:%d.%d SW:%d.%d PR-Sup:%s BWA-Sup:%s BWA-En:%s\n",
DP_TUNNELING_OUI_BYTES,
tunnel_reg_ptr(®s, DP_TUNNELING_OUI),
dev_id_len(tunnel_reg_ptr(®s, DP_TUNNELING_DEV_ID), DP_TUNNELING_DEV_ID_BYTES),
tunnel_reg_ptr(®s, DP_TUNNELING_DEV_ID),
(tunnel_reg(®s, DP_TUNNELING_HW_REV) & DP_TUNNELING_HW_REV_MAJOR_MASK) >>
DP_TUNNELING_HW_REV_MAJOR_SHIFT,
(tunnel_reg(®s, DP_TUNNELING_HW_REV) & DP_TUNNELING_HW_REV_MINOR_MASK) >>
DP_TUNNELING_HW_REV_MINOR_SHIFT,
tunnel_reg(®s, DP_TUNNELING_SW_REV_MAJOR),
tunnel_reg(®s, DP_TUNNELING_SW_REV_MINOR),
str_yes_no(tunnel_reg(®s, DP_TUNNELING_CAPABILITIES) &
DP_PANEL_REPLAY_OPTIMIZATION_SUPPORT),
str_yes_no(tunnel->bw_alloc_supported),
str_yes_no(tunnel->bw_alloc_enabled));
return tunnel;
}
EXPORT_SYMBOL(drm_dp_tunnel_detect);
/**
* drm_dp_tunnel_destroy - Destroy tunnel object
* @tunnel: Tunnel object
*
* Remove the tunnel from the tunnel topology and destroy it.
*
* Returns 0 on success, -ENODEV if the tunnel has been destroyed already.
*/
int drm_dp_tunnel_destroy(struct drm_dp_tunnel *tunnel)
{
if (!tunnel)
return 0;
if (drm_WARN_ON(tunnel->group->mgr->dev, tunnel->destroyed))
return -ENODEV;
tun_dbg(tunnel, "destroying\n");
tunnel->destroyed = true;
destroy_tunnel(tunnel);
return 0;
}
EXPORT_SYMBOL(drm_dp_tunnel_destroy);
static int check_tunnel(const struct drm_dp_tunnel *tunnel)
{
if (tunnel->destroyed)
return -ENODEV;
if (tunnel->has_io_error)
return -EIO;
return 0;
}
static int group_allocated_bw(struct drm_dp_tunnel_group *group)
{
struct drm_dp_tunnel *tunnel;
int group_allocated_bw = 0;
for_each_tunnel_in_group(group, tunnel) {
if (check_tunnel(tunnel) == 0 &&
tunnel->bw_alloc_enabled)
group_allocated_bw += tunnel_allocated_bw(tunnel);
}
return group_allocated_bw;
}
/*
* The estimated BW reported by the TBT Connection Manager for each tunnel in
* a group includes the BW already allocated for the given tunnel and the
* unallocated BW which is free to be used by any tunnel in the group.
*/
static int group_free_bw(const struct drm_dp_tunnel *tunnel)
{
return tunnel->estimated_bw - tunnel_allocated_bw(tunnel);
}
static int calc_group_available_bw(const struct drm_dp_tunnel *tunnel)
{
return group_allocated_bw(tunnel->group) +
group_free_bw(tunnel);
}
static int update_group_available_bw(struct drm_dp_tunnel *tunnel,
const struct drm_dp_tunnel_regs *regs)
{
struct drm_dp_tunnel *tunnel_iter;
int group_available_bw;
bool changed;
tunnel->estimated_bw = tunnel_reg(regs, DP_ESTIMATED_BW) * tunnel->bw_granularity;
if (calc_group_available_bw(tunnel) == tunnel->group->available_bw)
return 0;
for_each_tunnel_in_group(tunnel->group, tunnel_iter) {
int err;
if (tunnel_iter == tunnel)
continue;
if (check_tunnel(tunnel_iter) != 0 ||
!tunnel_iter->bw_alloc_enabled)
continue;
err = drm_dp_dpcd_probe(tunnel_iter->aux, DP_DPCD_REV);
if (err) {
tun_dbg(tunnel_iter,
"Probe failed, assume disconnected (err %pe)\n",
ERR_PTR(err));
drm_dp_tunnel_set_io_error(tunnel_iter);
}
}
group_available_bw = calc_group_available_bw(tunnel);
tun_dbg(tunnel, "Updated group available BW: %d->%d\n",
DPTUN_BW_ARG(tunnel->group->available_bw),
DPTUN_BW_ARG(group_available_bw));
changed = tunnel->group->available_bw != group_available_bw;
tunnel->group->available_bw = group_available_bw;
return changed ? 1 : 0;
}
static int set_bw_alloc_mode(struct drm_dp_tunnel *tunnel, bool enable)
{
u8 mask = DP_DISPLAY_DRIVER_BW_ALLOCATION_MODE_ENABLE | DP_UNMASK_BW_ALLOCATION_IRQ;
u8 val;
if (drm_dp_dpcd_readb(tunnel->aux, DP_DPTX_BW_ALLOCATION_MODE_CONTROL, &val) < 0)
goto out_err;
if (enable)
val |= mask;
else
val &= ~mask;
if (drm_dp_dpcd_writeb(tunnel->aux, DP_DPTX_BW_ALLOCATION_MODE_CONTROL, val) < 0)
goto out_err;
tunnel->bw_alloc_enabled = enable;
return 0;
out_err:
drm_dp_tunnel_set_io_error(tunnel);
return -EIO;
}
/**
* drm_dp_tunnel_enable_bw_alloc - Enable DP tunnel BW allocation mode
* @tunnel: Tunnel object
*
* Enable the DP tunnel BW allocation mode on @tunnel if it supports it.
*
* Returns 0 in case of success, negative error code otherwise.
*/
int drm_dp_tunnel_enable_bw_alloc(struct drm_dp_tunnel *tunnel)
{
struct drm_dp_tunnel_regs regs;
int err;
err = check_tunnel(tunnel);
if (err)
return err;
if (!tunnel->bw_alloc_supported)
return -EOPNOTSUPP;
if (!tunnel_group_id(tunnel->group->drv_group_id))
return -EINVAL;
err = set_bw_alloc_mode(tunnel, true);
if (err)
goto out;
/*
* After a BWA disable/re-enable sequence the allocated BW can either
* stay at its last requested value or, for instance after system
* suspend/resume, TBT CM can reset back the allocation to the amount
* allocated in the legacy/non-BWA mode. Accordingly allow for the
* allocation to change wrt. the last SW state.
*/
err = read_and_verify_tunnel_regs(tunnel, ®s,
ALLOW_ALLOCATED_BW_CHANGE);
if (err) {
set_bw_alloc_mode(tunnel, false);
goto out;
}
if (!tunnel->max_dprx_rate)
update_dprx_caps(tunnel, ®s);
if (tunnel->group->available_bw == -1) {
err = update_group_available_bw(tunnel, ®s);
if (err > 0)
err = 0;
}
out:
tun_dbg_stat(tunnel, err,
"Enabling BW alloc mode: DPRX:%dx%d Group alloc:%d/%d Mb/s",
tunnel->max_dprx_rate / 100, tunnel->max_dprx_lane_count,
DPTUN_BW_ARG(group_allocated_bw(tunnel->group)),
DPTUN_BW_ARG(tunnel->group->available_bw));
return err;
}
EXPORT_SYMBOL(drm_dp_tunnel_enable_bw_alloc);
/**
* drm_dp_tunnel_disable_bw_alloc - Disable DP tunnel BW allocation mode
* @tunnel: Tunnel object
*
* Disable the DP tunnel BW allocation mode on @tunnel.
*
* Returns 0 in case of success, negative error code otherwise.
*/
int drm_dp_tunnel_disable_bw_alloc(struct drm_dp_tunnel *tunnel)
{
int err;
err = check_tunnel(tunnel);
if (err)
return err;
tunnel->allocated_bw = -1;
err = set_bw_alloc_mode(tunnel, false);
tun_dbg_stat(tunnel, err, "Disabling BW alloc mode");
return err;
}
EXPORT_SYMBOL(drm_dp_tunnel_disable_bw_alloc);
/**
* drm_dp_tunnel_bw_alloc_is_enabled - Query the BW allocation mode enabled state
* @tunnel: Tunnel object
*
* Query if the BW allocation mode is enabled for @tunnel.
*
* Returns %true if the BW allocation mode is enabled for @tunnel.
*/
bool drm_dp_tunnel_bw_alloc_is_enabled(const struct drm_dp_tunnel *tunnel)
{
return tunnel && tunnel->bw_alloc_enabled;
}
EXPORT_SYMBOL(drm_dp_tunnel_bw_alloc_is_enabled);
static int clear_bw_req_state(struct drm_dp_aux *aux)
{
u8 bw_req_mask = DP_BW_REQUEST_SUCCEEDED | DP_BW_REQUEST_FAILED;
if (drm_dp_dpcd_writeb(aux, DP_TUNNELING_STATUS, bw_req_mask) < 0)
return -EIO;
return 0;
}
static int bw_req_complete(struct drm_dp_aux *aux, bool *status_changed)
{
u8 bw_req_mask = DP_BW_REQUEST_SUCCEEDED | DP_BW_REQUEST_FAILED;
u8 status_change_mask = DP_BW_ALLOCATION_CAPABILITY_CHANGED | DP_ESTIMATED_BW_CHANGED;
u8 val;
int err;
if (drm_dp_dpcd_readb(aux, DP_TUNNELING_STATUS, &val) < 0)
return -EIO;
*status_changed = val & status_change_mask;
val &= bw_req_mask;
if (!val)
return -EAGAIN;
err = clear_bw_req_state(aux);
if (err < 0)
return err;
return val == DP_BW_REQUEST_SUCCEEDED ? 0 : -ENOSPC;
}
static int allocate_tunnel_bw(struct drm_dp_tunnel *tunnel, int bw)
{
struct drm_dp_tunnel_mgr *mgr = tunnel->group->mgr;
int request_bw = DIV_ROUND_UP(bw, tunnel->bw_granularity);
DEFINE_WAIT_FUNC(wait, woken_wake_function);
long timeout;
int err;
if (bw < 0) {
err = -EINVAL;
goto out;
}
if (request_bw * tunnel->bw_granularity == tunnel->allocated_bw)
return 0;
/* Atomic check should prevent the following. */
if (drm_WARN_ON(mgr->dev, request_bw > MAX_DP_REQUEST_BW)) {
err = -EINVAL;
goto out;
}
err = clear_bw_req_state(tunnel->aux);
if (err)
goto out;
if (drm_dp_dpcd_writeb(tunnel->aux, DP_REQUEST_BW, request_bw) < 0) {
err = -EIO;
goto out;
}
timeout = msecs_to_jiffies(3000);
add_wait_queue(&mgr->bw_req_queue, &wait);
for (;;) {
bool status_changed;
err = bw_req_complete(tunnel->aux, &status_changed);
if (err != -EAGAIN)
break;
if (status_changed) {
struct drm_dp_tunnel_regs regs;
err = read_and_verify_tunnel_regs(tunnel, ®s,
ALLOW_ALLOCATED_BW_CHANGE);
if (err)
break;
}
if (!timeout) {
err = -ETIMEDOUT;
break;
}
timeout = wait_woken(&wait, TASK_UNINTERRUPTIBLE, timeout);
};
remove_wait_queue(&mgr->bw_req_queue, &wait);
if (err)
goto out;
tunnel->allocated_bw = request_bw * tunnel->bw_granularity;
out:
tun_dbg_stat(tunnel, err, "Allocating %d/%d Mb/s for tunnel: Group alloc:%d/%d Mb/s",
DPTUN_BW_ARG(request_bw * tunnel->bw_granularity),
DPTUN_BW_ARG(get_max_tunnel_bw(tunnel)),
DPTUN_BW_ARG(group_allocated_bw(tunnel->group)),
DPTUN_BW_ARG(tunnel->group->available_bw));
if (err == -EIO)
drm_dp_tunnel_set_io_error(tunnel);
return err;
}
/**
* drm_dp_tunnel_alloc_bw - Allocate BW for a DP tunnel
* @tunnel: Tunnel object
* @bw: BW in kB/s units
*
* Allocate @bw kB/s for @tunnel. The allocated BW must be freed after use by
* calling this function for the same tunnel setting @bw to 0.
*
* Returns 0 in case of success, a negative error code otherwise.
*/
int drm_dp_tunnel_alloc_bw(struct drm_dp_tunnel *tunnel, int bw)
{
int err;
err = check_tunnel(tunnel);
if (err)
return err;
return allocate_tunnel_bw(tunnel, bw);
}
EXPORT_SYMBOL(drm_dp_tunnel_alloc_bw);
/**
* drm_dp_tunnel_get_allocated_bw - Get the BW allocated for a DP tunnel
* @tunnel: Tunnel object
*
* Get the current BW allocated for @tunnel. After the tunnel is created /
* resumed and the BW allocation mode is enabled for it, the allocation
* becomes determined only after the first allocation request by the driver
* calling drm_dp_tunnel_alloc_bw().
*
* Return the BW allocated for the tunnel, or -1 if the allocation is
* undetermined.
*/
int drm_dp_tunnel_get_allocated_bw(struct drm_dp_tunnel *tunnel)
{
return tunnel->allocated_bw;
}
EXPORT_SYMBOL(drm_dp_tunnel_get_allocated_bw);
/*
* Return 0 if the status hasn't changed, 1 if the status has changed, a
* negative error code in case of an I/O failure.
*/
static int check_and_clear_status_change(struct drm_dp_tunnel *tunnel)
{
u8 mask = DP_BW_ALLOCATION_CAPABILITY_CHANGED | DP_ESTIMATED_BW_CHANGED;
u8 val;
if (drm_dp_dpcd_readb(tunnel->aux, DP_TUNNELING_STATUS, &val) < 0)
goto out_err;
val &= mask;
if (val) {
if (drm_dp_dpcd_writeb(tunnel->aux, DP_TUNNELING_STATUS, val) < 0)
goto out_err;
return 1;
}
if (!drm_dp_tunnel_bw_alloc_is_enabled(tunnel))
return 0;
/*
* Check for estimated BW changes explicitly to account for lost
* BW change notifications.
*/
if (drm_dp_dpcd_readb(tunnel->aux, DP_ESTIMATED_BW, &val) < 0)
goto out_err;
if (val * tunnel->bw_granularity != tunnel->estimated_bw)
return 1;
return 0;
out_err:
drm_dp_tunnel_set_io_error(tunnel);
return -EIO;
}
/**
* drm_dp_tunnel_update_state - Update DP tunnel SW state with the HW state
* @tunnel: Tunnel object
*
* Update the SW state of @tunnel with the HW state.
*
* Returns 0 if the state has not changed, 1 if it has changed and got updated
* successfully and a negative error code otherwise.
*/
int drm_dp_tunnel_update_state(struct drm_dp_tunnel *tunnel)
{
struct drm_dp_tunnel_regs regs;
bool changed = false;
int ret;
ret = check_tunnel(tunnel);
if (ret < 0)
return ret;
ret = check_and_clear_status_change(tunnel);
if (ret < 0)
goto out;
if (!ret)
return 0;
ret = read_and_verify_tunnel_regs(tunnel, ®s, 0);
if (ret)
goto out;
if (update_dprx_caps(tunnel, ®s))
changed = true;
ret = update_group_available_bw(tunnel, ®s);
if (ret == 1)
changed = true;
out:
tun_dbg_stat(tunnel, ret < 0 ? ret : 0,
"State update: Changed:%s DPRX:%dx%d Tunnel alloc:%d/%d Group alloc:%d/%d Mb/s",
str_yes_no(changed),
tunnel->max_dprx_rate / 100, tunnel->max_dprx_lane_count,
DPTUN_BW_ARG(tunnel->allocated_bw),
DPTUN_BW_ARG(get_max_tunnel_bw(tunnel)),
DPTUN_BW_ARG(group_allocated_bw(tunnel->group)),
DPTUN_BW_ARG(tunnel->group->available_bw));
if (ret < 0)
return ret;
if (changed)
return 1;
return 0;
}
EXPORT_SYMBOL(drm_dp_tunnel_update_state);
/*
* drm_dp_tunnel_handle_irq - Handle DP tunnel IRQs
*
* Handle any pending DP tunnel IRQs, waking up waiters for a completion
* event.
*
* Returns 1 if the state of the tunnel has changed which requires calling
* drm_dp_tunnel_update_state(), a negative error code in case of a failure,
* 0 otherwise.
*/
int drm_dp_tunnel_handle_irq(struct drm_dp_tunnel_mgr *mgr, struct drm_dp_aux *aux)
{
u8 val;
if (drm_dp_dpcd_readb(aux, DP_TUNNELING_STATUS, &val) < 0)
return -EIO;
if (val & (DP_BW_REQUEST_SUCCEEDED | DP_BW_REQUEST_FAILED))
wake_up_all(&mgr->bw_req_queue);
if (val & (DP_BW_ALLOCATION_CAPABILITY_CHANGED | DP_ESTIMATED_BW_CHANGED))
return 1;
return 0;
}
EXPORT_SYMBOL(drm_dp_tunnel_handle_irq);
/**
* drm_dp_tunnel_max_dprx_rate - Query the maximum rate of the tunnel's DPRX
* @tunnel: Tunnel object
*
* The function is used to query the maximum link rate of the DPRX connected
* to @tunnel. Note that this rate will not be limited by the BW limit of the
* tunnel, as opposed to the standard and extended DP_MAX_LINK_RATE DPCD
* registers.
*
* Returns the maximum link rate in 10 kbit/s units.
*/
int drm_dp_tunnel_max_dprx_rate(const struct drm_dp_tunnel *tunnel)
{
return tunnel->max_dprx_rate;
}
EXPORT_SYMBOL(drm_dp_tunnel_max_dprx_rate);
/**
* drm_dp_tunnel_max_dprx_lane_count - Query the maximum lane count of the tunnel's DPRX
* @tunnel: Tunnel object
*
* The function is used to query the maximum lane count of the DPRX connected
* to @tunnel. Note that this lane count will not be limited by the BW limit of
* the tunnel, as opposed to the standard and extended DP_MAX_LANE_COUNT DPCD
* registers.
*
* Returns the maximum lane count.
*/
int drm_dp_tunnel_max_dprx_lane_count(const struct drm_dp_tunnel *tunnel)
{
return tunnel->max_dprx_lane_count;
}
EXPORT_SYMBOL(drm_dp_tunnel_max_dprx_lane_count);
/**
* drm_dp_tunnel_available_bw - Query the estimated total available BW of the tunnel
* @tunnel: Tunnel object
*
* This function is used to query the estimated total available BW of the
* tunnel. This includes the currently allocated and free BW for all the
* tunnels in @tunnel's group. The available BW is valid only after the BW
* allocation mode has been enabled for the tunnel and its state got updated
* calling drm_dp_tunnel_update_state().
*
* Returns the @tunnel group's estimated total available bandwidth in kB/s
* units, or -1 if the available BW isn't valid (the BW allocation mode is
* not enabled or the tunnel's state hasn't been updated).
*/
int drm_dp_tunnel_available_bw(const struct drm_dp_tunnel *tunnel)
{
return tunnel->group->available_bw;
}
EXPORT_SYMBOL(drm_dp_tunnel_available_bw);
static struct drm_dp_tunnel_group_state *
drm_dp_tunnel_atomic_get_group_state(struct drm_atomic_state *state,
const struct drm_dp_tunnel *tunnel)
{
return (struct drm_dp_tunnel_group_state *)
drm_atomic_get_private_obj_state(state,
&tunnel->group->base);
}
static struct drm_dp_tunnel_state *
add_tunnel_state(struct drm_dp_tunnel_group_state *group_state,
struct drm_dp_tunnel *tunnel)
{
struct drm_dp_tunnel_state *tunnel_state;
tun_dbg_atomic(tunnel,
"Adding state for tunnel %p to group state %p\n",
tunnel, group_state);
tunnel_state = kzalloc(sizeof(*tunnel_state), GFP_KERNEL);
if (!tunnel_state)
return NULL;
tunnel_state->group_state = group_state;
drm_dp_tunnel_ref_get(tunnel, &tunnel_state->tunnel_ref);
INIT_LIST_HEAD(&tunnel_state->node);
list_add(&tunnel_state->node, &group_state->tunnel_states);
return tunnel_state;
}
static void free_tunnel_state(struct drm_dp_tunnel_state *tunnel_state)
{
tun_dbg_atomic(tunnel_state->tunnel_ref.tunnel,
"Freeing state for tunnel %p\n",
tunnel_state->tunnel_ref.tunnel);
list_del(&tunnel_state->node);
kfree(tunnel_state->stream_bw);
drm_dp_tunnel_ref_put(&tunnel_state->tunnel_ref);
kfree(tunnel_state);
}
static void free_group_state(struct drm_dp_tunnel_group_state *group_state)
{
struct drm_dp_tunnel_state *tunnel_state;
struct drm_dp_tunnel_state *tunnel_state_tmp;
for_each_tunnel_state_safe(group_state, tunnel_state, tunnel_state_tmp)
free_tunnel_state(tunnel_state);
kfree(group_state);
}
static struct drm_dp_tunnel_state *
get_tunnel_state(struct drm_dp_tunnel_group_state *group_state,
const struct drm_dp_tunnel *tunnel)
{
struct drm_dp_tunnel_state *tunnel_state;
for_each_tunnel_state(group_state, tunnel_state)
if (tunnel_state->tunnel_ref.tunnel == tunnel)
return tunnel_state;
return NULL;
}
static struct drm_dp_tunnel_state *
get_or_add_tunnel_state(struct drm_dp_tunnel_group_state *group_state,
struct drm_dp_tunnel *tunnel)
{
struct drm_dp_tunnel_state *tunnel_state;
tunnel_state = get_tunnel_state(group_state, tunnel);
if (tunnel_state)
return tunnel_state;
return add_tunnel_state(group_state, tunnel);
}
static struct drm_private_state *
tunnel_group_duplicate_state(struct drm_private_obj *obj)
{
struct drm_dp_tunnel_group_state *group_state;
struct drm_dp_tunnel_state *tunnel_state;
group_state = kzalloc(sizeof(*group_state), GFP_KERNEL);
if (!group_state)
return NULL;
INIT_LIST_HEAD(&group_state->tunnel_states);
__drm_atomic_helper_private_obj_duplicate_state(obj, &group_state->base);
for_each_tunnel_state(to_group_state(obj->state), tunnel_state) {
struct drm_dp_tunnel_state *new_tunnel_state;
new_tunnel_state = get_or_add_tunnel_state(group_state,
tunnel_state->tunnel_ref.tunnel);
if (!new_tunnel_state)
goto out_free_state;
new_tunnel_state->stream_mask = tunnel_state->stream_mask;
new_tunnel_state->stream_bw = kmemdup(tunnel_state->stream_bw,
sizeof(*tunnel_state->stream_bw) *
hweight32(tunnel_state->stream_mask),
GFP_KERNEL);
if (!new_tunnel_state->stream_bw)
goto out_free_state;
}
return &group_state->base;
out_free_state:
free_group_state(group_state);
return NULL;
}
static void tunnel_group_destroy_state(struct drm_private_obj *obj, struct drm_private_state *state)
{
free_group_state(to_group_state(state));
}
static const struct drm_private_state_funcs tunnel_group_funcs = {
.atomic_duplicate_state = tunnel_group_duplicate_state,
.atomic_destroy_state = tunnel_group_destroy_state,
};
/**
* drm_dp_tunnel_atomic_get_state - get/allocate the new atomic state for a tunnel
* @state: Atomic state
* @tunnel: Tunnel to get the state for
*
* Get the new atomic state for @tunnel, duplicating it from the old tunnel
* state if not yet allocated.
*
* Return the state or an ERR_PTR() error on failure.
*/
struct drm_dp_tunnel_state *
drm_dp_tunnel_atomic_get_state(struct drm_atomic_state *state,
struct drm_dp_tunnel *tunnel)
{
struct drm_dp_tunnel_group_state *group_state;
struct drm_dp_tunnel_state *tunnel_state;
group_state = drm_dp_tunnel_atomic_get_group_state(state, tunnel);
if (IS_ERR(group_state))
return ERR_CAST(group_state);
tunnel_state = get_or_add_tunnel_state(group_state, tunnel);
if (!tunnel_state)
return ERR_PTR(-ENOMEM);
return tunnel_state;
}
EXPORT_SYMBOL(drm_dp_tunnel_atomic_get_state);
/**
* drm_dp_tunnel_atomic_get_old_state - get the old atomic state for a tunnel
* @state: Atomic state
* @tunnel: Tunnel to get the state for
*
* Get the old atomic state for @tunnel.
*
* Return the old state or NULL if the tunnel's atomic state is not in @state.
*/
struct drm_dp_tunnel_state *
drm_dp_tunnel_atomic_get_old_state(struct drm_atomic_state *state,
const struct drm_dp_tunnel *tunnel)
{
struct drm_dp_tunnel_group_state *old_group_state;
int i;
for_each_old_group_in_state(state, old_group_state, i)
if (to_group(old_group_state->base.obj) == tunnel->group)
return get_tunnel_state(old_group_state, tunnel);
return NULL;
}
EXPORT_SYMBOL(drm_dp_tunnel_atomic_get_old_state);
/**
* drm_dp_tunnel_atomic_get_new_state - get the new atomic state for a tunnel
* @state: Atomic state
* @tunnel: Tunnel to get the state for
*
* Get the new atomic state for @tunnel.
*
* Return the new state or NULL if the tunnel's atomic state is not in @state.
*/
struct drm_dp_tunnel_state *
drm_dp_tunnel_atomic_get_new_state(struct drm_atomic_state *state,
const struct drm_dp_tunnel *tunnel)
{
struct drm_dp_tunnel_group_state *new_group_state;
int i;
for_each_new_group_in_state(state, new_group_state, i)
if (to_group(new_group_state->base.obj) == tunnel->group)
return get_tunnel_state(new_group_state, tunnel);
return NULL;
}
EXPORT_SYMBOL(drm_dp_tunnel_atomic_get_new_state);
static bool init_group(struct drm_dp_tunnel_mgr *mgr, struct drm_dp_tunnel_group *group)
{
struct drm_dp_tunnel_group_state *group_state;
group_state = kzalloc(sizeof(*group_state), GFP_KERNEL);
if (!group_state)
return false;
INIT_LIST_HEAD(&group_state->tunnel_states);
group->mgr = mgr;
group->available_bw = -1;
INIT_LIST_HEAD(&group->tunnels);
drm_atomic_private_obj_init(mgr->dev, &group->base, &group_state->base,
&tunnel_group_funcs);
return true;
}
static void cleanup_group(struct drm_dp_tunnel_group *group)
{
drm_atomic_private_obj_fini(&group->base);
}
#ifdef CONFIG_DRM_DISPLAY_DP_TUNNEL_STATE_DEBUG
static void check_unique_stream_ids(const struct drm_dp_tunnel_group_state *group_state)
{
const struct drm_dp_tunnel_state *tunnel_state;
u32 stream_mask = 0;
for_each_tunnel_state(group_state, tunnel_state) {
drm_WARN(to_group(group_state->base.obj)->mgr->dev,
tunnel_state->stream_mask & stream_mask,
"[DPTUN %s]: conflicting stream IDs %x (IDs in other tunnels %x)\n",
tunnel_state->tunnel_ref.tunnel->name,
tunnel_state->stream_mask,
stream_mask);
stream_mask |= tunnel_state->stream_mask;
}
}
#else
static void check_unique_stream_ids(const struct drm_dp_tunnel_group_state *group_state)
{
}
#endif
static int stream_id_to_idx(u32 stream_mask, u8 stream_id)
{
return hweight32(stream_mask & (BIT(stream_id) - 1));
}
static int resize_bw_array(struct drm_dp_tunnel_state *tunnel_state,
unsigned long old_mask, unsigned long new_mask)
{
unsigned long move_mask = old_mask & new_mask;
int *new_bws = NULL;
int id;
WARN_ON(!new_mask);
if (old_mask == new_mask)
return 0;
new_bws = kcalloc(hweight32(new_mask), sizeof(*new_bws), GFP_KERNEL);
if (!new_bws)
return -ENOMEM;
for_each_set_bit(id, &move_mask, BITS_PER_TYPE(move_mask))
new_bws[stream_id_to_idx(new_mask, id)] =
tunnel_state->stream_bw[stream_id_to_idx(old_mask, id)];
kfree(tunnel_state->stream_bw);
tunnel_state->stream_bw = new_bws;
tunnel_state->stream_mask = new_mask;
return 0;
}
static int set_stream_bw(struct drm_dp_tunnel_state *tunnel_state,
u8 stream_id, int bw)
{
int err;
err = resize_bw_array(tunnel_state,
tunnel_state->stream_mask,
tunnel_state->stream_mask | BIT(stream_id));
if (err)
return err;
tunnel_state->stream_bw[stream_id_to_idx(tunnel_state->stream_mask, stream_id)] = bw;
return 0;
}
static int clear_stream_bw(struct drm_dp_tunnel_state *tunnel_state,
u8 stream_id)
{
if (!(tunnel_state->stream_mask & ~BIT(stream_id))) {
free_tunnel_state(tunnel_state);
return 0;
}
return resize_bw_array(tunnel_state,
tunnel_state->stream_mask,
tunnel_state->stream_mask & ~BIT(stream_id));
}
/**
* drm_dp_tunnel_atomic_set_stream_bw - Set the BW for a DP tunnel stream
* @state: Atomic state
* @tunnel: DP tunnel containing the stream
* @stream_id: Stream ID
* @bw: BW of the stream
*
* Set a DP tunnel stream's required BW in the atomic state.
*
* Returns 0 in case of success, a negative error code otherwise.
*/
int drm_dp_tunnel_atomic_set_stream_bw(struct drm_atomic_state *state,
struct drm_dp_tunnel *tunnel,
u8 stream_id, int bw)
{
struct drm_dp_tunnel_group_state *new_group_state;
struct drm_dp_tunnel_state *tunnel_state;
int err;
if (drm_WARN_ON(tunnel->group->mgr->dev,
stream_id > BITS_PER_TYPE(tunnel_state->stream_mask)))
return -EINVAL;
tun_dbg(tunnel,
"Setting %d Mb/s for stream %d\n",
DPTUN_BW_ARG(bw), stream_id);
new_group_state = drm_dp_tunnel_atomic_get_group_state(state, tunnel);
if (IS_ERR(new_group_state))
return PTR_ERR(new_group_state);
if (bw == 0) {
tunnel_state = get_tunnel_state(new_group_state, tunnel);
if (!tunnel_state)
return 0;
return clear_stream_bw(tunnel_state, stream_id);
}
tunnel_state = get_or_add_tunnel_state(new_group_state, tunnel);
if (drm_WARN_ON(state->dev, !tunnel_state))
return -EINVAL;
err = set_stream_bw(tunnel_state, stream_id, bw);
if (err)
return err;
check_unique_stream_ids(new_group_state);
return 0;
}
EXPORT_SYMBOL(drm_dp_tunnel_atomic_set_stream_bw);
/**
* drm_dp_tunnel_atomic_get_required_bw - Get the BW required by a DP tunnel
* @tunnel_state: Atomic state of the queried tunnel
*
* Calculate the BW required by a tunnel adding up the required BW of all
* the streams in the tunnel.
*
* Return the total BW required by the tunnel.
*/
int drm_dp_tunnel_atomic_get_required_bw(const struct drm_dp_tunnel_state *tunnel_state)
{
int tunnel_bw = 0;
int i;
if (!tunnel_state || !tunnel_state->stream_mask)
return 0;
for (i = 0; i < hweight32(tunnel_state->stream_mask); i++)
tunnel_bw += tunnel_state->stream_bw[i];
return tunnel_bw;
}
EXPORT_SYMBOL(drm_dp_tunnel_atomic_get_required_bw);
/**
* drm_dp_tunnel_atomic_get_group_streams_in_state - Get mask of stream IDs in a group
* @state: Atomic state
* @tunnel: Tunnel object
* @stream_mask: Mask of streams in @tunnel's group
*
* Get the mask of all the stream IDs in the tunnel group of @tunnel.
*
* Return 0 in case of success - with the stream IDs in @stream_mask - or a
* negative error code in case of failure.
*/
int drm_dp_tunnel_atomic_get_group_streams_in_state(struct drm_atomic_state *state,
const struct drm_dp_tunnel *tunnel,
u32 *stream_mask)
{
struct drm_dp_tunnel_group_state *group_state;
struct drm_dp_tunnel_state *tunnel_state;
group_state = drm_dp_tunnel_atomic_get_group_state(state, tunnel);
if (IS_ERR(group_state))
return PTR_ERR(group_state);
*stream_mask = 0;
for_each_tunnel_state(group_state, tunnel_state)
*stream_mask |= tunnel_state->stream_mask;
return 0;
}
EXPORT_SYMBOL(drm_dp_tunnel_atomic_get_group_streams_in_state);
static int
drm_dp_tunnel_atomic_check_group_bw(struct drm_dp_tunnel_group_state *new_group_state,
u32 *failed_stream_mask)
{
struct drm_dp_tunnel_group *group = to_group(new_group_state->base.obj);
struct drm_dp_tunnel_state *new_tunnel_state;
u32 group_stream_mask = 0;
int group_bw = 0;
for_each_tunnel_state(new_group_state, new_tunnel_state) {
struct drm_dp_tunnel *tunnel = new_tunnel_state->tunnel_ref.tunnel;
int max_dprx_bw = get_max_dprx_bw(tunnel);
int tunnel_bw = drm_dp_tunnel_atomic_get_required_bw(new_tunnel_state);
tun_dbg(tunnel,
"%sRequired %d/%d Mb/s total for tunnel.\n",
tunnel_bw > max_dprx_bw ? "Not enough BW: " : "",
DPTUN_BW_ARG(tunnel_bw),
DPTUN_BW_ARG(max_dprx_bw));
if (tunnel_bw > max_dprx_bw) {
*failed_stream_mask = new_tunnel_state->stream_mask;
return -ENOSPC;
}
group_bw += min(roundup(tunnel_bw, tunnel->bw_granularity),
max_dprx_bw);
group_stream_mask |= new_tunnel_state->stream_mask;
}
tun_grp_dbg(group,
"%sRequired %d/%d Mb/s total for tunnel group.\n",
group_bw > group->available_bw ? "Not enough BW: " : "",
DPTUN_BW_ARG(group_bw),
DPTUN_BW_ARG(group->available_bw));
if (group_bw > group->available_bw) {
*failed_stream_mask = group_stream_mask;
return -ENOSPC;
}
return 0;
}
/**
* drm_dp_tunnel_atomic_check_stream_bws - Check BW limit for all streams in state
* @state: Atomic state
* @failed_stream_mask: Mask of stream IDs with a BW limit failure
*
* Check the required BW of each DP tunnel in @state against both the DPRX BW
* limit of the tunnel and the BW limit of the tunnel group. Return a mask of
* stream IDs in @failed_stream_mask once a check fails. The mask will contain
* either all the streams in a tunnel (in case a DPRX BW limit check failed) or
* all the streams in a tunnel group (in case a group BW limit check failed).
*
* Return 0 if all the BW limit checks passed, -ENOSPC in case a BW limit
* check failed - with @failed_stream_mask containing the streams failing the
* check - or a negative error code otherwise.
*/
int drm_dp_tunnel_atomic_check_stream_bws(struct drm_atomic_state *state,
u32 *failed_stream_mask)
{
struct drm_dp_tunnel_group_state *new_group_state;
int i;
for_each_new_group_in_state(state, new_group_state, i) {
int ret;
ret = drm_dp_tunnel_atomic_check_group_bw(new_group_state,
failed_stream_mask);
if (ret)
return ret;
}
return 0;
}
EXPORT_SYMBOL(drm_dp_tunnel_atomic_check_stream_bws);
static void destroy_mgr(struct drm_dp_tunnel_mgr *mgr)
{
int i;
for (i = 0; i < mgr->group_count; i++) {
cleanup_group(&mgr->groups[i]);
drm_WARN_ON(mgr->dev, !list_empty(&mgr->groups[i].tunnels));
}
#ifdef CONFIG_DRM_DISPLAY_DP_TUNNEL_STATE_DEBUG
ref_tracker_dir_exit(&mgr->ref_tracker);
#endif
kfree(mgr->groups);
kfree(mgr);
}
/**
* drm_dp_tunnel_mgr_create - Create a DP tunnel manager
* @dev: DRM device object
* @max_group_count: Maximum number of tunnel groups
*
* Creates a DP tunnel manager for @dev.
*
* Returns a pointer to the tunnel manager if created successfully or NULL in
* case of an error.
*/
struct drm_dp_tunnel_mgr *
drm_dp_tunnel_mgr_create(struct drm_device *dev, int max_group_count)
{
struct drm_dp_tunnel_mgr *mgr;
int i;
mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
if (!mgr)
return NULL;
mgr->dev = dev;
init_waitqueue_head(&mgr->bw_req_queue);
mgr->groups = kcalloc(max_group_count, sizeof(*mgr->groups), GFP_KERNEL);
if (!mgr->groups) {
kfree(mgr);
return NULL;
}
#ifdef CONFIG_DRM_DISPLAY_DP_TUNNEL_STATE_DEBUG
ref_tracker_dir_init(&mgr->ref_tracker, 16, "dptun");
#endif
for (i = 0; i < max_group_count; i++) {
if (!init_group(mgr, &mgr->groups[i])) {
destroy_mgr(mgr);
return NULL;
}
mgr->group_count++;
}
return mgr;
}
EXPORT_SYMBOL(drm_dp_tunnel_mgr_create);
/**
* drm_dp_tunnel_mgr_destroy - Destroy DP tunnel manager
* @mgr: Tunnel manager object
*
* Destroy the tunnel manager.
*/
void drm_dp_tunnel_mgr_destroy(struct drm_dp_tunnel_mgr *mgr)
{
destroy_mgr(mgr);
}
EXPORT_SYMBOL(drm_dp_tunnel_mgr_destroy);
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