diff options
72 files changed, 4419 insertions, 671 deletions
diff --git a/drivers/gpu/drm/display/Kconfig b/drivers/gpu/drm/display/Kconfig index 09712b88a5b8..c0f56888c328 100644 --- a/drivers/gpu/drm/display/Kconfig +++ b/drivers/gpu/drm/display/Kconfig @@ -17,6 +17,27 @@ config DRM_DISPLAY_DP_HELPER help DRM display helpers for DisplayPort. +config DRM_DISPLAY_DP_TUNNEL + bool + select DRM_DISPLAY_DP_HELPER + help + Enable support for DisplayPort tunnels. This allows drivers to use + DP tunnel features like the Bandwidth Allocation mode to maximize the + BW utilization for display streams on Thunderbolt links. + +config DRM_DISPLAY_DEBUG_DP_TUNNEL_STATE + bool "Enable debugging the DP tunnel state" + depends on REF_TRACKER + depends on DRM_DISPLAY_DP_TUNNEL + depends on DEBUG_KERNEL + depends on EXPERT + help + Enables debugging the DP tunnel manager's state, including the + consistency of all managed tunnels' reference counting and the state of + streams contained in tunnels. + + If in doubt, say "N". + config DRM_DISPLAY_HDCP_HELPER bool depends on DRM_DISPLAY_HELPER diff --git a/drivers/gpu/drm/display/Makefile b/drivers/gpu/drm/display/Makefile index 17ac4a1006a8..7ca61333c669 100644 --- a/drivers/gpu/drm/display/Makefile +++ b/drivers/gpu/drm/display/Makefile @@ -8,6 +8,8 @@ drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_HELPER) += \ drm_dp_helper.o \ drm_dp_mst_topology.o \ drm_dsc_helper.o +drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_TUNNEL) += \ + drm_dp_tunnel.o drm_display_helper-$(CONFIG_DRM_DISPLAY_HDCP_HELPER) += drm_hdcp_helper.o drm_display_helper-$(CONFIG_DRM_DISPLAY_HDMI_HELPER) += \ drm_hdmi_helper.o \ diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index 8d6ce46471ae..d046dfa79504 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -4055,3 +4055,33 @@ int drm_dp_bw_channel_coding_efficiency(bool is_uhbr) return 800000; } EXPORT_SYMBOL(drm_dp_bw_channel_coding_efficiency); + +/** + * drm_dp_max_dprx_data_rate - Get the max data bandwidth of a DPRX sink + * @max_link_rate: max DPRX link rate in 10kbps units + * @max_lanes: max DPRX lane count + * + * Given a link rate and lanes, get the data bandwidth. + * + * Data bandwidth is the actual payload rate, which depends on the data + * bandwidth efficiency and the link rate. + * + * Note that protocol layers above the DPRX link level considered here can + * further limit the maximum data rate. Such layers are the MST topology (with + * limits on the link between the source and first branch device as well as on + * the whole MST path until the DPRX link) and (Thunderbolt) DP tunnels - + * which in turn can encapsulate an MST link with its own limit - with each + * SST or MST encapsulated tunnel sharing the BW of a tunnel group. + * + * Returns the maximum data rate in kBps units. + */ +int drm_dp_max_dprx_data_rate(int max_link_rate, int max_lanes) +{ + int ch_coding_efficiency = + drm_dp_bw_channel_coding_efficiency(drm_dp_is_uhbr_rate(max_link_rate)); + + return DIV_ROUND_DOWN_ULL(mul_u32_u32(max_link_rate * 10 * max_lanes, + ch_coding_efficiency), + 1000000 * 8); +} +EXPORT_SYMBOL(drm_dp_max_dprx_data_rate); diff --git a/drivers/gpu/drm/display/drm_dp_tunnel.c b/drivers/gpu/drm/display/drm_dp_tunnel.c new file mode 100644 index 000000000000..120e0de674c1 --- /dev/null +++ b/drivers/gpu/drm/display/drm_dp_tunnel.c @@ -0,0 +1,1949 @@ +// 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_DEBUG_DP_TUNNEL_STATE + 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_DEBUG_DP_TUNNEL_STATE +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 + * |