diff options
Diffstat (limited to 'drivers/gpu/drm/display')
| -rw-r--r-- | drivers/gpu/drm/display/Kconfig | 21 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/Makefile | 2 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_aux_bus.c | 2 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_helper.c | 179 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_mst_topology.c | 23 | ||||
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_tunnel.c | 1949 |
6 files changed, 2156 insertions, 20 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_aux_bus.c b/drivers/gpu/drm/display/drm_dp_aux_bus.c index 8a165be1a821..5afc26be9d2a 100644 --- a/drivers/gpu/drm/display/drm_dp_aux_bus.c +++ b/drivers/gpu/drm/display/drm_dp_aux_bus.c @@ -127,7 +127,7 @@ static void dp_aux_ep_shutdown(struct device *dev) aux_ep_drv->shutdown(to_dp_aux_ep_dev(dev)); } -static struct bus_type dp_aux_bus_type = { +static const struct bus_type dp_aux_bus_type = { .name = "dp-aux", .match = dp_aux_ep_match, .probe = dp_aux_ep_probe, diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index 26c188ce5f1c..f5d4be897866 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -533,6 +533,15 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request, mutex_lock(&aux->hw_mutex); /* + * If the device attached to the aux bus is powered down then there's + * no reason to attempt a transfer. Error out immediately. + */ + if (aux->powered_down) { + ret = -EBUSY; + goto unlock; + } + + /* * The specification doesn't give any recommendation on how often to * retry native transactions. We used to retry 7 times like for * aux i2c transactions but real world devices this wasn't @@ -600,6 +609,29 @@ int drm_dp_dpcd_probe(struct drm_dp_aux *aux, unsigned int offset) EXPORT_SYMBOL(drm_dp_dpcd_probe); /** + * drm_dp_dpcd_set_powered() - Set whether the DP device is powered + * @aux: DisplayPort AUX channel; for convenience it's OK to pass NULL here + * and the function will be a no-op. + * @powered: true if powered; false if not + * + * If the endpoint device on the DP AUX bus is known to be powered down + * then this function can be called to make future transfers fail immediately + * instead of needing to time out. + * + * If this function is never called then a device defaults to being powered. + */ +void drm_dp_dpcd_set_powered(struct drm_dp_aux *aux, bool powered) +{ + if (!aux) + return; + + mutex_lock(&aux->hw_mutex); + aux->powered_down = !powered; + mutex_unlock(&aux->hw_mutex); +} +EXPORT_SYMBOL(drm_dp_dpcd_set_powered); + +/** * drm_dp_dpcd_read() - read a series of bytes from the DPCD * @aux: DisplayPort AUX channel (SST or MST) * @offset: address of the (first) register to read @@ -1858,6 +1890,9 @@ static int drm_dp_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, struct drm_dp_aux_msg msg; int err = 0; + if (aux->powered_down) + return -EBUSY; + dp_aux_i2c_transfer_size = clamp(dp_aux_i2c_transfer_size, 1, DP_AUX_MAX_PAYLOAD_BYTES); memset(&msg, 0, sizeof(msg)); @@ -2897,26 +2932,120 @@ static const char *dp_content_type_get_name(enum dp_content_type content_type) } } -void drm_dp_vsc_sdp_log(const char *level, struct device *dev, - const struct drm_dp_vsc_sdp *vsc) +void drm_dp_vsc_sdp_log(struct drm_printer *p, const struct drm_dp_vsc_sdp *vsc) { -#define DP_SDP_LOG(fmt, ...) dev_printk(level, dev, fmt, ##__VA_ARGS__) - DP_SDP_LOG("DP SDP: %s, revision %u, length %u\n", "VSC", + drm_printf(p, "DP SDP: VSC, revision %u, length %u\n", vsc->revision, vsc->length); - DP_SDP_LOG(" pixelformat: %s\n", + drm_printf(p, " pixelformat: %s\n", dp_pixelformat_get_name(vsc->pixelformat)); - DP_SDP_LOG(" colorimetry: %s\n", + drm_printf(p, " colorimetry: %s\n", dp_colorimetry_get_name(vsc->pixelformat, vsc->colorimetry)); - DP_SDP_LOG(" bpc: %u\n", vsc->bpc); - DP_SDP_LOG(" dynamic range: %s\n", + drm_printf(p, " bpc: %u\n", vsc->bpc); + drm_printf(p, " dynamic range: %s\n", dp_dynamic_range_get_name(vsc->dynamic_range)); - DP_SDP_LOG(" content type: %s\n", + drm_printf(p, " content type: %s\n", dp_content_type_get_name(vsc->content_type)); -#undef DP_SDP_LOG } EXPORT_SYMBOL(drm_dp_vsc_sdp_log); /** + * drm_dp_vsc_sdp_supported() - check if vsc sdp is supported + * @aux: DisplayPort AUX channel + * @dpcd: DisplayPort configuration data + * + * Returns true if vsc sdp is supported, else returns false + */ +bool drm_dp_vsc_sdp_supported(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + u8 rx_feature; + + if (dpcd[DP_DPCD_REV] < DP_DPCD_REV_13) + return false; + + if (drm_dp_dpcd_readb(aux, DP_DPRX_FEATURE_ENUMERATION_LIST, &rx_feature) != 1) { + drm_dbg_dp(aux->drm_dev, "failed to read DP_DPRX_FEATURE_ENUMERATION_LIST\n"); + return false; + } + + return (rx_feature & DP_VSC_SDP_EXT_FOR_COLORIMETRY_SUPPORTED); +} +EXPORT_SYMBOL(drm_dp_vsc_sdp_supported); + +/** + * drm_dp_vsc_sdp_pack() - pack a given vsc sdp into generic dp_sdp + * @vsc: vsc sdp initialized according to its purpose as defined in + * table 2-118 - table 2-120 in DP 1.4a specification + * @sdp: valid handle to the generic dp_sdp which will be packed + * + * Returns length of sdp on success and error code on failure + */ +ssize_t drm_dp_vsc_sdp_pack(const struct drm_dp_vsc_sdp *vsc, + struct dp_sdp *sdp) +{ + size_t length = sizeof(struct dp_sdp); + + memset(sdp, 0, sizeof(struct dp_sdp)); + + /* + * Prepare VSC Header for SU as per DP 1.4a spec, Table 2-119 + * VSC SDP Header Bytes + */ + sdp->sdp_header.HB0 = 0; /* Secondary-Data Packet ID = 0 */ + sdp->sdp_header.HB1 = vsc->sdp_type; /* Secondary-data Packet Type */ + sdp->sdp_header.HB2 = vsc->revision; /* Revision Number */ + sdp->sdp_header.HB3 = vsc->length; /* Number of Valid Data Bytes */ + + if (vsc->revision == 0x6) { + sdp->db[0] = 1; + sdp->db[3] = 1; + } + + /* + * Revision 0x5 and revision 0x7 supports Pixel Encoding/Colorimetry + * Format as per DP 1.4a spec and DP 2.0 respectively. + */ + if (!(vsc->revision == 0x5 || vsc->revision == 0x7)) + goto out; + + /* VSC SDP Payload for DB16 through DB18 */ + /* Pixel Encoding and Colorimetry Formats */ + sdp->db[16] = (vsc->pixelformat & 0xf) << 4; /* DB16[7:4] */ + sdp->db[16] |= vsc->colorimetry & 0xf; /* DB16[3:0] */ + + switch (vsc->bpc) { + case 6: + /* 6bpc: 0x0 */ + break; + case 8: + sdp->db[17] = 0x1; /* DB17[3:0] */ + break; + case 10: + sdp->db[17] = 0x2; + break; + case 12: + sdp->db[17] = 0x3; + break; + case 16: + sdp->db[17] = 0x4; + break; + default: + WARN(1, "Missing case %d\n", vsc->bpc); + return -EINVAL; + } + + /* Dynamic Range and Component Bit Depth */ + if (vsc->dynamic_range == DP_DYNAMIC_RANGE_CTA) + sdp->db[17] |= 0x80; /* DB17[7] */ + + /* Content Type */ + sdp->db[18] = vsc->content_type & 0x7; + +out: + return length; +} +EXPORT_SYMBOL(drm_dp_vsc_sdp_pack); + +/** * drm_dp_get_pcon_max_frl_bw() - maximum frl supported by PCON * @dpcd: DisplayPort configuration data * @port_cap: port capabilities @@ -4065,3 +4194,33 @@ 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_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c index f7c6b60629c2..03d528209426 100644 --- a/drivers/gpu/drm/display/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c @@ -1306,7 +1306,8 @@ static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb, } out: if (unlikely(ret == -EIO) && drm_debug_enabled(DRM_UT_DP)) { - struct drm_printer p = drm_debug_printer(DBG_PREFIX); + struct drm_printer p = drm_dbg_printer(mgr->dev, DRM_UT_DP, + DBG_PREFIX); drm_dp_mst_dump_sideband_msg_tx(&p, txmsg); } @@ -1593,10 +1594,11 @@ topology_ref_type_to_str(enum drm_dp_mst_topology_ref_type type) } static void -__dump_topology_ref_history(struct drm_dp_mst_topology_ref_history *history, +__dump_topology_ref_history(struct drm_device *drm, + struct drm_dp_mst_topology_ref_history *history, void *ptr, const char *type_str) { - struct drm_printer p = drm_debug_printer(DBG_PREFIX); + struct drm_printer p = drm_dbg_printer(drm, DRM_UT_DP, DBG_PREFIX); char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL); int i; @@ -1638,15 +1640,15 @@ out: static __always_inline void drm_dp_mst_dump_mstb_topology_history(struct drm_dp_mst_branch *mstb) { - __dump_topology_ref_history(&mstb->topology_ref_history, mstb, - "MSTB"); + __dump_topology_ref_history(mstb->mgr->dev, &mstb->topology_ref_history, + mstb, "MSTB"); } static __always_inline void drm_dp_mst_dump_port_topology_history(struct drm_dp_mst_port *port) { - __dump_topology_ref_history(&port->topology_ref_history, port, - "Port"); + __dump_topology_ref_history(port->mgr->dev, &port->topology_ref_history, + port, "Port"); } static __always_inline void @@ -2824,7 +2826,9 @@ static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr, ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx); if (ret) { if (drm_debug_enabled(DRM_UT_DP)) { - struct drm_printer p = drm_debug_printer(DBG_PREFIX); + struct drm_printer p = drm_dbg_printer(mgr->dev, + DRM_UT_DP, + DBG_PREFIX); drm_printf(&p, "sideband msg failed to send\n"); drm_dp_mst_dump_sideband_msg_tx(&p, txmsg); @@ -2869,7 +2873,8 @@ static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr, list_add_tail(&txmsg->next, &mgr->tx_msg_downq); if (drm_debug_enabled(DRM_UT_DP)) { - struct drm_printer p = drm_debug_printer(DBG_PREFIX); + struct drm_printer p = drm_dbg_printer(mgr->dev, DRM_UT_DP, + DBG_PREFIX); drm_dp_mst_dump_sideband_msg_tx(&p, txmsg); } 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 + * 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; +} + < |