[PATCH v2 6/9] media: intel: Add Displayport RX IP driver
From: Paweł Anikiel
Date: Wed Feb 21 2024 - 11:05:33 EST
Add driver for the Intel DisplayPort RX FPGA IP
Signed-off-by: Paweł Anikiel <panikiel@xxxxxxxxxx>
---
drivers/media/platform/intel/Kconfig | 12 +
drivers/media/platform/intel/Makefile | 1 +
drivers/media/platform/intel/intel-dprx.c | 2176 +++++++++++++++++++++
3 files changed, 2189 insertions(+)
create mode 100644 drivers/media/platform/intel/intel-dprx.c
diff --git a/drivers/media/platform/intel/Kconfig b/drivers/media/platform/intel/Kconfig
index 724e80a9086d..eafcd47cce68 100644
--- a/drivers/media/platform/intel/Kconfig
+++ b/drivers/media/platform/intel/Kconfig
@@ -12,3 +12,15 @@ config VIDEO_PXA27x
select V4L2_FWNODE
help
This is a v4l2 driver for the PXA27x Quick Capture Interface
+
+config VIDEO_INTEL_DPRX
+ tristate "Intel DisplayPort RX IP driver"
+ depends on V4L_PLATFORM_DRIVERS
+ depends on VIDEO_DEV
+ select V4L2_FWNODE
+ select CRC_DP
+ help
+ v4l2 subdev driver for Intel Displayport receiver FPGA IP.
+ It is a part of the DisplayPort Intel FPGA IP Core.
+ It implements a DisplayPort 1.4 receiver capable of HBR3
+ video capture and Multi-Stream Transport.
diff --git a/drivers/media/platform/intel/Makefile b/drivers/media/platform/intel/Makefile
index 7e8889cbd2df..f571399f5aa8 100644
--- a/drivers/media/platform/intel/Makefile
+++ b/drivers/media/platform/intel/Makefile
@@ -1,2 +1,3 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_VIDEO_PXA27x) += pxa_camera.o
+obj-$(CONFIG_VIDEO_INTEL_DPRX) += intel-dprx.o
diff --git a/drivers/media/platform/intel/intel-dprx.c b/drivers/media/platform/intel/intel-dprx.c
new file mode 100644
index 000000000000..d0c60e29e51d
--- /dev/null
+++ b/drivers/media/platform/intel/intel-dprx.c
@@ -0,0 +1,2176 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2023-2024 Google LLC.
+ * Author: Paweł Anikiel <panikiel@xxxxxxxxxx>
+ */
+
+#include <linux/crc-dp.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <media/v4l2-dv-timings.h>
+#include <media/v4l2-subdev.h>
+#include <drm/display/drm_dp.h>
+#include <drm/display/drm_dp_mst.h>
+
+#define DPRX_MAX_EDID_BLOCKS 4
+
+/* DPRX registers */
+
+#define DPRX_RX_CONTROL 0x000
+#define DPRX_RX_CONTROL_LINK_RATE_SHIFT 16
+#define DPRX_RX_CONTROL_LINK_RATE_MASK 0xff
+#define DPRX_RX_CONTROL_RECONFIG_LINKRATE 13
+#define DPRX_RX_CONTROL_TP_SHIFT 8
+#define DPRX_RX_CONTROL_TP_MASK 0x7
+#define DPRX_RX_CONTROL_SCRAMBLER_DISABLE 7
+#define DPRX_RX_CONTROL_CHANNEL_CODING_SHIFT 5
+#define DPRX_RX_CONTROL_CHANNEL_CODING_8B10B 0x1
+#define DPRX_RX_CONTROL_LANE_COUNT_SHIFT 0
+#define DPRX_RX_CONTROL_LANE_COUNT_MASK 0x1f
+
+#define DPRX_RX_STATUS 0x001
+#define DPRX_RX_STATUS_INTERLANE_ALIGN 8
+#define DPRX_RX_STATUS_SYM_LOCK_SHIFT 4
+#define DPRX_RX_STATUS_SYM_LOCK(i) (4 + i)
+#define DPRX_RX_STATUS_CR_LOCK_SHIFT 0
+#define DPRX_RX_STATUS_CR_LOCK(i) (0 + i)
+
+#define DPRX_MSA_HTOTAL(i) (0x022 + 0x20 * (i))
+#define DPRX_MSA_VTOTAL(i) (0x023 + 0x20 * (i))
+#define DPRX_MSA_HSP(i) (0x024 + 0x20 * (i))
+#define DPRX_MSA_HSW(i) (0x025 + 0x20 * (i))
+#define DPRX_MSA_HSTART(i) (0x026 + 0x20 * (i))
+#define DPRX_MSA_VSTART(i) (0x027 + 0x20 * (i))
+#define DPRX_MSA_VSP(i) (0x028 + 0x20 * (i))
+#define DPRX_MSA_VSW(i) (0x029 + 0x20 * (i))
+#define DPRX_MSA_HWIDTH(i) (0x02a + 0x20 * (i))
+#define DPRX_MSA_VHEIGHT(i) (0x02b + 0x20 * (i))
+#define DPRX_VBID(i) (0x02f + 0x20 * (i))
+#define DPRX_VBID_MSA_LOCK 7
+
+#define DPRX_MST_CONTROL1 0x0a0
+#define DPRX_MST_CONTROL1_VCPTAB_UPD_FORCE 31
+#define DPRX_MST_CONTROL1_VCPTAB_UPD_REQ 30
+#define DPRX_MST_CONTROL1_VCP_ID_SHIFT(i) (4 + 4 * (i))
+#define DPRX_MST_CONTROL1_VCP_IDS_SHIFT 4
+#define DPRX_MST_CONTROL1_VCP_IDS_MASK 0xffff
+#define DPRX_MST_CONTROL1_MST_EN 0
+
+#define DPRX_MST_STATUS1 0x0a1
+#define DPRX_MST_STATUS1_VCPTAB_ACT_ACK 30
+
+#define DPRX_MST_VCPTAB(i) (0x0a2 + i)
+
+#define DPRX_AUX_CONTROL 0x100
+#define DPRX_AUX_CONTROL_IRQ_EN 8
+#define DPRX_AUX_CONTROL_TX_STROBE 7
+#define DPRX_AUX_CONTROL_LENGTH_SHIFT 0
+#define DPRX_AUX_CONTROL_LENGTH_MASK 0x1f
+
+#define DPRX_AUX_STATUS 0x101
+#define DPRX_AUX_STATUS_MSG_READY 31
+#define DPRX_AUX_STATUS_READY_TO_TX 30
+
+#define DPRX_AUX_COMMAND 0x102
+
+#define DPRX_AUX_HPD 0x119
+#define DPRX_AUX_HPD_IRQ 12
+#define DPRX_AUX_HPD_EN 11
+
+/* DDC defines */
+
+#define DDC_EDID_ADDR 0x50
+#define DDC_SEGMENT_ADDR 0x30
+
+struct dprx_training_control {
+ u8 volt_swing;
+ u8 pre_emph;
+ bool max_swing;
+ bool max_pre_emph;
+};
+
+struct dprx_sink {
+ u8 edid[128 * DPRX_MAX_EDID_BLOCKS];
+ int blocks;
+ int offset;
+ int segment;
+};
+
+struct msg_transaction_rxbuf {
+ u8 buf[256];
+ int len;
+};
+
+struct msg_transaction_txbuf {
+ u8 buf[256];
+ int len;
+ int written;
+};
+
+struct msg_transaction_meta {
+ u8 lct;
+ u8 rad[8];
+ bool seqno;
+};
+
+struct dprx {
+ struct device *dev;
+ void __iomem *iobase;
+
+ struct v4l2_subdev subdev;
+ struct media_pad pads[4];
+
+ struct dprx_sink sinks[4];
+
+ int max_link_rate;
+ int max_lane_count;
+ bool multi_stream_support;
+ int max_stream_count;
+
+ u8 caps[16];
+ u8 guid[16];
+
+ struct dprx_training_control training_control[4];
+
+ u8 payload_allocate_set;
+ u8 payload_allocate_start_time_slot;
+ u8 payload_allocate_time_slot_count;
+ u8 payload_table[64];
+ u8 payload_table_updated;
+
+ u8 payload_id[4];
+ u32 payload_pbn[4];
+ u32 payload_pbn_total;
+
+ u8 irq_vector;
+
+ u8 down_req_buf[48];
+ u8 down_rep_buf[48];
+
+ struct msg_transaction_rxbuf mt_rxbuf[2];
+ struct msg_transaction_txbuf mt_txbuf[2];
+ struct msg_transaction_meta mt_meta[2];
+ bool mt_seqno;
+ bool mt_pending;
+ bool down_rep_pending;
+
+ spinlock_t lock;
+};
+
+struct aux_buf {
+ u8 data[20];
+ int len;
+};
+
+struct aux_msg {
+ u8 cmd;
+ u32 addr;
+ u8 len;
+ u8 data[16];
+};
+
+struct sideband_msg {
+ u8 lct;
+ u8 lcr;
+ u8 rad[8];
+ bool broadcast;
+ bool path_msg;
+ bool somt;
+ bool eomt;
+ bool seqno;
+
+ u8 body[48];
+ u8 body_len;
+};
+
+static void dprx_write(struct dprx *dprx, int addr, u32 val)
+{
+ writel(val, dprx->iobase + (addr * 4));
+}
+
+static u32 dprx_read(struct dprx *dprx, int addr)
+{
+ return readl(dprx->iobase + (addr * 4));
+}
+
+static void dprx_set_irq(struct dprx *dprx, int val)
+{
+ u32 reg;
+
+ reg = dprx_read(dprx, DPRX_AUX_CONTROL);
+ reg |= ~(1 << DPRX_AUX_CONTROL_IRQ_EN);
+ reg |= val << DPRX_AUX_CONTROL_IRQ_EN;
+ dprx_write(dprx, DPRX_AUX_CONTROL, reg);
+}
+
+static void dprx_set_hpd(struct dprx *dprx, int val)
+{
+ u32 reg;
+
+ reg = dprx_read(dprx, DPRX_AUX_HPD);
+ reg &= ~(1 << DPRX_AUX_HPD_EN);
+ reg |= val << DPRX_AUX_HPD_EN;
+ dprx_write(dprx, DPRX_AUX_HPD, reg);
+}
+
+static void dprx_pulse_hpd(struct dprx *dprx)
+{
+ u32 reg;
+
+ reg = dprx_read(dprx, DPRX_AUX_HPD);
+ reg |= 1 << DPRX_AUX_HPD_IRQ;
+ dprx_write(dprx, DPRX_AUX_HPD, reg);
+}
+
+static void dprx_clear_vc_payload_table(struct dprx *dprx)
+{
+ u32 reg;
+ int i;
+
+ memset(dprx->payload_table, 0, sizeof(dprx->payload_table));
+
+ for (i = 0; i < 8; i++)
+ dprx_write(dprx, DPRX_MST_VCPTAB(i), 0);
+
+ reg = dprx_read(dprx, DPRX_MST_CONTROL1);
+ reg &= ~(DPRX_MST_CONTROL1_VCP_IDS_MASK << DPRX_MST_CONTROL1_VCP_IDS_SHIFT);
+ reg |= 1 << DPRX_MST_CONTROL1_VCPTAB_UPD_FORCE;
+ dprx_write(dprx, DPRX_MST_CONTROL1, reg);
+}
+
+static void dprx_set_vc_payload_table(struct dprx *dprx)
+{
+ int i, j;
+ u32 reg;
+ u8 val;
+
+ /*
+ * The IP core only accepts VC payload IDs of 1-4. Thus, we need to
+ * remap the 1-63 range allowed by DisplayPort into 1-4. However, some
+ * hosts first set the VC payload table and then allocate the VC
+ * payload IDs, which means we can't remap the range immediately.
+ *
+ * It is probably possible to force a VC payload table update (without
+ * waiting for a ACT trigger) when the IDs change, but for now we just
+ * ignore IDs higher than 4.
+ */
+ for (i = 0; i < 8; i++) {
+ reg = 0;
+ for (j = 0; j < 8; j++) {
+ val = dprx->payload_table[i*8+j];
+ if (val <= 4)
+ reg |= val << (j * 4);
+ }
+ dprx_write(dprx, DPRX_MST_VCPTAB(i), reg);
+ }
+
+ reg = dprx_read(dprx, DPRX_MST_CONTROL1);
+ reg |= 1 << DPRX_MST_CONTROL1_VCPTAB_UPD_REQ;
+ dprx_write(dprx, DPRX_MST_CONTROL1, reg);
+}
+
+static void dprx_set_vc_ids(struct dprx *dprx)
+{
+ u32 reg;
+ int i;
+
+ reg = dprx_read(dprx, DPRX_MST_CONTROL1);
+ reg &= ~(DPRX_MST_CONTROL1_VCP_IDS_MASK << DPRX_MST_CONTROL1_VCP_IDS_SHIFT);
+ for (i = 0; i < dprx->max_stream_count; i++) {
+ if (dprx->payload_id[i] <= 4)
+ reg |= dprx->payload_id[i] << DPRX_MST_CONTROL1_VCP_ID_SHIFT(i);
+ }
+ dprx_write(dprx, DPRX_MST_CONTROL1, reg);
+}
+
+static void dprx_allocate_vc_payload(struct dprx *dprx, u8 start, u8 count, u8 id)
+{
+ if (count > sizeof(dprx->payload_table) - start)
+ count = sizeof(dprx->payload_table) - start;
+ memset(dprx->payload_table + start, id, count);
+}
+
+static void dprx_deallocate_vc_payload(struct dprx *dprx, int start, u8 id)
+{
+ u8 to = start;
+ u8 i;
+
+ for (i = start; i < sizeof(dprx->payload_table); i++) {
+ if (dprx->payload_table[i] == id)
+ dprx->payload_table[i] = 0;
+ else
+ dprx->payload_table[to++] = dprx->payload_table[i];
+ }
+}
+
+static u32 dprx_full_pbn(struct dprx *dprx)
+{
+ u32 reg;
+ u32 lane_count;
+ u32 link_rate;
+
+ if ((dprx_read(dprx, DPRX_RX_STATUS) >> DPRX_RX_STATUS_INTERLANE_ALIGN) & 1) {
+ /* link training done - get current bandwidth */
+ reg = dprx_read(dprx, DPRX_RX_CONTROL);
+ lane_count = (reg >> DPRX_RX_CONTROL_LANE_COUNT_SHIFT) &
+ DPRX_RX_CONTROL_LANE_COUNT_MASK;
+ link_rate = (reg >> DPRX_RX_CONTROL_LINK_RATE_SHIFT) &
+ DPRX_RX_CONTROL_LINK_RATE_MASK;
+ } else {
+ /* link training not done - get max bandwidth */
+ lane_count = dprx->max_lane_count;
+ link_rate = dprx->max_link_rate;
+ }
+
+ return lane_count * link_rate * 32;
+}
+
+static int dprx_port_number_to_sink_idx(struct dprx *dprx, u8 port_number)
+{
+ /* check if port number is valid */
+ if (port_number < DP_MST_LOGICAL_PORT_0 ||
+ port_number >= DP_MST_LOGICAL_PORT_0 + dprx->max_stream_count)
+ return -1;
+
+ return port_number - DP_MST_LOGICAL_PORT_0;
+}
+
+static bool dprx_adjust_needed(struct dprx *dprx)
+{
+ u32 control;
+ u32 status;
+ u32 lane_count;
+ u32 lane_count_mask;
+ u32 pattern;
+
+ control = dprx_read(dprx, DPRX_RX_CONTROL);
+ status = dprx_read(dprx, DPRX_RX_STATUS);
+
+ pattern = (control >> DPRX_RX_CONTROL_TP_SHIFT) & DPRX_RX_CONTROL_TP_MASK;
+ lane_count = (control >> DPRX_RX_CONTROL_LANE_COUNT_SHIFT) &
+ DPRX_RX_CONTROL_LANE_COUNT_MASK;
+ lane_count_mask = (1 << lane_count) - 1;
+
+ if (pattern == 0) {
+ /* link training not in progress */
+ return false;
+ } else if (pattern == 1) {
+ /* link training CR phase - check CR lock */
+ return (~status) & (lane_count_mask << DPRX_RX_STATUS_CR_LOCK_SHIFT);
+ }
+ /* link training EQ phase - check synbol lock and interlane align */
+ return (~status) & (lane_count_mask << DPRX_RX_STATUS_SYM_LOCK_SHIFT |
+ 1 << DPRX_RX_STATUS_INTERLANE_ALIGN);
+}
+
+/*
+ * Return next allowed voltage swing, and pre-emphasis pair.
+ * DisplayPort 1.2 spec, section 3.1.5.2
+ */
+static void dprx_training_control_next(struct dprx_training_control *ctl,
+ u8 *next_volt_swing, u8 *next_pre_emph)
+{
+ u8 volt_swing = ctl->volt_swing;
+ u8 pre_emph = ctl->pre_emph;
+
+ pre_emph++;
+ if (pre_emph > 2) {
+ volt_swing++;
+ pre_emph = 0;
+ }
+
+ if (volt_swing > 2 || (volt_swing == 2 && pre_emph == 2)) {
+ volt_swing = 0;
+ pre_emph = 0;
+ }
+
+ *next_volt_swing = volt_swing;
+ *next_pre_emph = pre_emph;
+}
+
+static int dprx_i2c_read(struct dprx_sink *sink, u8 addr, u8 *buf, int len)
+{
+ int offset;
+
+ if (len == 0)
+ return 0;
+
+ switch (addr) {
+ case DDC_EDID_ADDR:
+ offset = sink->offset + sink->segment * 256;
+ if (len + offset > sink->blocks * 128)
+ return -1;
+ memcpy(buf, sink->edid + offset, len);
+ sink->offset += len;
+ break;
+ case DDC_SEGMENT_ADDR:
+ if (len > 1)
+ return -1;
+ buf[0] = sink->segment;
+ break;
+ default:
+ return -1;
+ }
+
+ return 0;
+}
+
+static int dprx_i2c_write(struct dprx_sink *sink, u8 addr, u8 *buf, int len)
+{
+ if (len == 0)
+ return 0;
+ if (len > 1)
+ return -1;
+
+ switch (addr) {
+ case DDC_EDID_ADDR:
+ sink->offset = buf[0];
+ break;
+ case DDC_SEGMENT_ADDR:
+ sink->segment = buf[0];
+ break;
+ default:
+ return -1;
+ }
+
+ return 0;
+}
+
+static void dprx_i2c_stop(struct dprx_sink *sink)
+{
+ sink->segment = 0;
+}
+
+static void dprx_write_nak(struct dprx *dprx,
+ struct drm_dp_sideband_msg_reply_body *rep,
+ u8 req_type, u8 reason)
+{
+ rep->reply_type = DP_SIDEBAND_REPLY_NAK;
+ rep->req_type = req_type;
+
+ memcpy(rep->u.nak.guid, dprx->guid, sizeof(dprx->guid));
+ rep->u.nak.reason = reason;
+ rep->u.nak.nak_data = 0;
+}
+
+static void dprx_execute_link_address(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ struct drm_dp_link_address_ack_reply *link_address = &rep->u.link_addr;
+ struct drm_dp_link_addr_reply_port *port = link_address->ports;
+ int i;
+
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_LINK_ADDRESS;
+
+ memcpy(link_address->guid, dprx->guid, sizeof(dprx->guid));
+ link_address->nports = dprx->max_stream_count + 1;
+
+ /* Port 0: input (physical) */
+ port->input_port = true;
+ port->peer_device_type = DP_PEER_DEVICE_SOURCE_OR_SST;
+ port->port_number = 0;
+ port->mcs = false;
+ port->ddps = true;
+ port++;
+
+ for (i = 0; i < dprx->max_stream_count; i++) {
+ /* Port 8 + n: internal sink number n (logical) */
+ port->input_port = false;
+ port->port_number = DP_MST_LOGICAL_PORT_0 + i;
+ port->mcs = false;
+ if (dprx->sinks[i].blocks > 0) {
+ port->peer_device_type = DP_PEER_DEVICE_SST_SINK;
+ port->ddps = true;
+ } else {
+ port->peer_device_type = DP_PEER_DEVICE_NONE;
+ port->ddps = false;
+ }
+ port->legacy_device_plug_status = false;
+ port->dpcd_revision = 0;
+ memset(port->peer_guid, 0, 16);
+ port->num_sdp_streams = 0;
+ port->num_sdp_stream_sinks = 0;
+ port++;
+ }
+}
+
+static void dprx_execute_connection_status_notify(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_CONNECTION_STATUS_NOTIFY;
+}
+
+static void dprx_execute_enum_path_resources(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ u32 full_pbn = dprx_full_pbn(dprx);
+
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_ENUM_PATH_RESOURCES;
+
+ rep->u.path_resources.port_number = req->u.port_num.port_number;
+ rep->u.path_resources.fec_capable = false;
+ rep->u.path_resources.full_payload_bw_number = full_pbn;
+ if (dprx->payload_pbn_total > full_pbn)
+ rep->u.path_resources.avail_payload_bw_number = 0;
+ else
+ rep->u.path_resources.avail_payload_bw_number = full_pbn - dprx->payload_pbn_total;
+}
+
+static void dprx_execute_allocate_payload(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ struct drm_dp_allocate_payload *a_req = &req->u.allocate_payload;
+ struct drm_dp_allocate_payload_ack_reply *a_rep = &rep->u.allocate_payload;
+ int sink_idx;
+
+ sink_idx = dprx_port_number_to_sink_idx(dprx, a_req->port_number);
+ if (sink_idx == -1) {
+ dprx_write_nak(dprx, rep, req->req_type, DP_NAK_BAD_PARAM);
+ return;
+ }
+
+ if (a_req->vcpi == 0) {
+ dprx_write_nak(dprx, rep, req->req_type, DP_NAK_BAD_PARAM);
+ return;
+ }
+
+ if (a_req->pbn > 0) {
+ if (dprx->payload_pbn[sink_idx] == 0) {
+ /* New payload ID */
+ dprx->payload_id[sink_idx] = a_req->vcpi;
+ } else if (dprx->payload_id[sink_idx] != a_req->vcpi) {
+ /* At most one payload ID is allowed per sink */
+ dprx_write_nak(dprx, rep, req->req_type, DP_NAK_ALLOCATE_FAIL);
+ return;
+ }
+ }
+ WARN_ON_ONCE(dprx->payload_pbn_total < dprx->payload_pbn[sink_idx]);
+ dprx->payload_pbn_total -= dprx->payload_pbn[sink_idx];
+ dprx->payload_pbn_total += a_req->pbn;
+ dprx->payload_pbn[sink_idx] = a_req->pbn;
+
+ dprx_set_vc_ids(dprx);
+
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_ALLOCATE_PAYLOAD;
+
+ a_rep->port_number = a_req->port_number;
+ a_rep->vcpi = a_req->vcpi;
+ a_rep->allocated_pbn = a_req->pbn;
+}
+
+static void dprx_execute_clear_payload_id_table(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_CLEAR_PAYLOAD_ID_TABLE;
+
+ dprx_clear_vc_payload_table(dprx);
+}
+
+static void dprx_execute_remote_dpcd_read(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ struct drm_dp_remote_dpcd_read *read_req = &req->u.dpcd_read;
+ struct drm_dp_remote_dpcd_read_ack_reply *read_rep = &rep->u.remote_dpcd_read_ack;
+
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_REMOTE_DPCD_READ;
+
+ read_rep->port_number = read_req->port_number;
+ read_rep->num_bytes = read_req->num_bytes;
+ memset(read_rep->bytes, 0, read_req->num_bytes);
+}
+
+static void dprx_execute_remote_i2c_read(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ struct drm_dp_remote_i2c_read *read_req = &req->u.i2c_read;
+ struct drm_dp_remote_i2c_read_ack_reply *read_rep = &rep->u.remote_i2c_read_ack;
+ struct drm_dp_remote_i2c_read_tx *tx;
+ struct dprx_sink *sink;
+ int sink_idx;
+ int res;
+ int i;
+
+ sink_idx = dprx_port_number_to_sink_idx(dprx, read_req->port_number);
+ if (sink_idx == -1) {
+ dprx_write_nak(dprx, rep, req->req_type, DP_NAK_BAD_PARAM);
+ return;
+ }
+ sink = &dprx->sinks[sink_idx];
+
+ for (i = 0; i < read_req->num_transactions; i++) {
+ tx = &read_req->transactions[i];
+ res = dprx_i2c_write(sink, tx->i2c_dev_id, tx->bytes, tx->num_bytes);
+ if (res)
+ goto i2c_err;
+ if (!tx->no_stop_bit)
+ dprx_i2c_stop(sink);
+ }
+
+ res = dprx_i2c_read(sink, read_req->read_i2c_device_id,
+ read_rep->bytes, read_req->num_bytes_read);
+ if (res)
+ goto i2c_err;
+ dprx_i2c_stop(sink);
+
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_REMOTE_I2C_READ;
+
+ read_rep->port_number = read_req->port_number;
+ read_rep->num_bytes = read_req->num_bytes_read;
+ return;
+
+i2c_err:
+ dprx_i2c_stop(sink);
+ dprx_write_nak(dprx, rep, req->req_type, DP_NAK_I2C_NAK);
+}
+
+static void dprx_execute_remote_i2c_write(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ struct drm_dp_remote_i2c_write *write_req = &req->u.i2c_write;
+ struct drm_dp_remote_i2c_write_ack_reply *write_rep = &rep->u.remote_i2c_write_ack;
+ struct dprx_sink *sink;
+ int sink_idx;
+ int res;
+
+ sink_idx = dprx_port_number_to_sink_idx(dprx, write_req->port_number);
+ if (sink_idx == -1) {
+ dprx_write_nak(dprx, rep, req->req_type, DP_NAK_BAD_PARAM);
+ return;
+ }
+ sink = &dprx->sinks[sink_idx];
+
+ res = dprx_i2c_write(sink, write_req->write_i2c_device_id,
+ write_req->bytes, write_req->num_bytes);
+ dprx_i2c_stop(sink);
+ if (res) {
+ dprx_write_nak(dprx, rep, req->req_type, DP_NAK_I2C_NAK);
+ return;
+ }
+
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_REMOTE_I2C_WRITE;
+ write_rep->port_number = write_req->port_number;
+}
+
+static void dprx_execute_power_up_phy(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_POWER_UP_PHY;
+ rep->u.port_number.port_number = req->u.port_num.port_number;
+}
+
+static void dprx_execute_power_down_phy(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ rep->reply_type = DP_SIDEBAND_REPLY_ACK;
+ rep->req_type = DP_POWER_DOWN_PHY;
+ rep->u.port_number.port_number = req->u.port_num.port_number;
+}
+
+static void dprx_encode_sideband_msg(struct sideband_msg *msg, u8 *buf)
+{
+ int idx = 0;
+ int i;
+ u8 crc4;
+
+ buf[idx++] = ((msg->lct & 0xf) << 4) | (msg->lcr & 0xf);
+ for (i = 0; i < (msg->lct / 2); i++)
+ buf[idx++] = msg->rad[i];
+ buf[idx++] = (msg->broadcast << 7) | (msg->path_msg << 6) |
+ ((msg->body_len + 1) & 0x3f);
+ buf[idx++] = (msg->somt << 7) | (msg->eomt << 6) | (msg->seqno << 4);
+
+ crc4 = crc_dp_msg_header(buf, (idx * 2) - 1);
+ buf[idx - 1] |= (crc4 & 0xf);
+
+ memcpy(&buf[idx], msg->body, msg->body_len);
+ idx += msg->body_len;
+ buf[idx] = crc_dp_msg_data(msg->body, msg->body_len);
+}
+
+static bool dprx_decode_sideband_msg(struct sideband_msg *msg, u8 *buf, int buflen)
+{
+ u8 hdr_crc;
+ u8 hdr_len;
+ u8 body_crc;
+ int i;
+ u8 idx;
+
+ if (buf[0] == 0)
+ return false;
+ hdr_len = 3;
+ hdr_len += ((buf[0] & 0xf0) >> 4) / 2;
+ if (hdr_len > buflen)
+ return false;
+ hdr_crc = crc_dp_msg_header(buf, (hdr_len * 2) - 1);
+ if ((hdr_crc & 0xf) != (buf[hdr_len - 1] & 0xf))
+ return false;
+
+ msg->lct = (buf[0] & 0xf0) >> 4;
+ msg->lcr = (buf[0] & 0xf);
+ idx = 1;
+ for (i = 0; i < (msg->lct / 2); i++)
+ msg->rad[i] = buf[idx++];
+ msg->broadcast = (buf[idx] >> 7) & 0x1;
+ msg->path_msg = (buf[idx] >> 6) & 0x1;
+ msg->body_len = (buf[idx] & 0x3f) - 1;
+ idx++;
+ msg->somt = (buf[idx] >> 7) & 0x1;
+ msg->eomt = (buf[idx] >> 6) & 0x1;
+ msg->seqno = (buf[idx] >> 4) & 0x1;
+ idx++;
+
+ if (hdr_len + msg->body_len + 1 != buflen)
+ return false;
+
+ body_crc = crc_dp_msg_data(&buf[idx], msg->body_len);
+ if (body_crc != buf[idx + msg->body_len])
+ return false;
+
+ memcpy(msg->body, &buf[idx], msg->body_len);
+ idx += msg->body_len;
+
+ return true;
+}
+
+static bool dprx_decode_port_number_req(struct drm_dp_port_number_req *port_num, u8 *buf, int len)
+{
+ if (len != 1)
+ return false;
+
+ port_num->port_number = buf[0] >> 4;
+
+ return true;
+}
+
+static bool
+dprx_decode_connection_status_notify_req(struct drm_dp_connection_status_notify *conn_stat,
+ u8 *buf, int len)
+{
+ int idx = 0;
+
+ if (len != 18)
+ return false;
+
+ conn_stat->port_number = buf[idx++];
+ memcpy(conn_stat->guid, &buf[idx], 16);
+ idx += 16;
+ conn_stat->legacy_device_plug_status = (buf[idx] >> 6) & 1;
+ conn_stat->displayport_device_plug_status = (buf[idx] >> 5) & 1;
+ conn_stat->message_capability_status = (buf[idx] >> 4) & 1;
+ conn_stat->input_port = (buf[idx] >> 3) & 1;
+ conn_stat->peer_device_type = buf[idx] & 0x7;
+
+ return true;
+}
+
+static bool dprx_decode_allocate_payload_req(struct drm_dp_allocate_payload *alloc_payload,
+ u8 *buf, int len)
+{
+ int idx = 0;
+ int i;
+
+ if (len < 4)
+ return false;
+
+ alloc_payload->port_number = buf[idx] >> 4;
+ alloc_payload->number_sdp_streams = buf[idx++] & 0xf;
+ alloc_payload->vcpi = buf[idx++] & 0x7f;
+ alloc_payload->pbn = buf[idx] << 8 | buf[idx + 1];
+ idx += 2;
+
+ if (len != idx + (alloc_payload->number_sdp_streams + 1) / 2)
+ return false;
+
+ for (i = 0; i < alloc_payload->number_sdp_streams; i++) {
+ if ((i & 1) == 0) {
+ alloc_payload->sdp_stream_sink[i] = buf[idx] >> 4;
+ } else {
+ alloc_payload->sdp_stream_sink[i] = buf[idx] & 0xf;
+ idx++;
+ }
+ }
+
+ return true;
+}
+
+static bool dprx_decode_remote_dpcd_read_req(struct drm_dp_remote_dpcd_read *dpcd_read,
+ u8 *buf, int len)
+{
+ if (len != 4)
+ return false;
+
+ dpcd_read->port_number = buf[0] >> 4;
+ dpcd_read->dpcd_address = (buf[0] & 0xf) << 16 | buf[1] << 8 | buf[2];
+ dpcd_read->num_bytes = buf[3];
+
+ return true;
+}
+
+static bool dprx_decode_remote_i2c_read_req(struct drm_dp_remote_i2c_read *i2c_read,
+ u8 *buf, int len)
+{
+ struct drm_dp_remote_i2c_read_tx *tx;
+ int idx = 0;
+ int i;
+
+ if (len < 1)
+ return false;
+
+ i2c_read->port_number = buf[idx] >> 4;
+ i2c_read->num_transactions = buf[idx] & 0x3;
+ idx++;
+
+ for (i = 0; i < i2c_read->num_transactions; i++) {
+ tx = &i2c_read->transactions[i];
+ if (len < idx + 2)
+ return false;
+ tx->i2c_dev_id = buf[idx++] & 0x7f;
+ tx->num_bytes = buf[idx++];
+ if (len < idx + tx->num_bytes + 1)
+ return -1;
+ tx->bytes = &buf[idx];
+ idx += tx->num_bytes;
+ tx->no_stop_bit = (buf[idx] >> 4) & 1;
+ tx->i2c_transaction_delay = buf[idx] & 0xf;
+ idx++;
+ }
+
+ if (len != idx + 2)
+ return false;
+
+ i2c_read->read_i2c_device_id = buf[idx++] & 0x7f;
+ i2c_read->num_bytes_read = buf[idx++];
+
+ return true;
+}
+
+static bool dprx_decode_remote_i2c_write_req(struct drm_dp_remote_i2c_write *i2c_write,
+ u8 *buf, int len)
+{
+ int idx = 0;
+
+ if (len < 3)
+ return false;
+
+ i2c_write->port_number = buf[idx++] >> 4;
+ i2c_write->write_i2c_device_id = buf[idx++] & 0x7f;
+ i2c_write->num_bytes = buf[idx++];
+
+ if (len != idx + i2c_write->num_bytes)
+ return false;
+
+ i2c_write->bytes = &buf[idx];
+
+ return true;
+}
+
+static bool dprx_decode_sideband_req(struct drm_dp_sideband_msg_req_body *req, u8 *buf, int len)
+{
+ if (len == 0)
+ return false;
+
+ req->req_type = buf[0] & 0x7f;
+ buf++;
+ len--;
+
+ switch (req->req_type) {
+ case DP_LINK_ADDRESS:
+ case DP_CLEAR_PAYLOAD_ID_TABLE:
+ return len == 0; /* no request data */
+ case DP_ENUM_PATH_RESOURCES:
+ case DP_POWER_UP_PHY:
+ case DP_POWER_DOWN_PHY:
+ return dprx_decode_port_number_req(&req->u.port_num, buf, len);
+ case DP_CONNECTION_STATUS_NOTIFY:
+ return dprx_decode_connection_status_notify_req(&req->u.conn_stat, buf, len);
+ case DP_ALLOCATE_PAYLOAD:
+ return dprx_decode_allocate_payload_req(&req->u.allocate_payload, buf, len);
+ case DP_REMOTE_DPCD_READ:
+ return dprx_decode_remote_dpcd_read_req(&req->u.dpcd_read, buf, len);
+ case DP_REMOTE_I2C_READ:
+ return dprx_decode_remote_i2c_read_req(&req->u.i2c_read, buf, len);
+ case DP_REMOTE_I2C_WRITE:
+ return dprx_decode_remote_i2c_write_req(&req->u.i2c_write, buf, len);
+ default:
+ return false;
+ }
+}
+
+static void dprx_encode_sideband_rep(struct drm_dp_sideband_msg_reply_body *rep, u8 *buf, int *len)
+{
+ int idx = 0;
+ int i;
+
+ buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
+
+ if (rep->reply_type) {
+ memcpy(&buf[idx], rep->u.nak.guid, 16);
+ idx += 16;
+ buf[idx++] = rep->u.nak.reason;
+ buf[idx++] = rep->u.nak.nak_data;
+ *len = idx;
+ return;
+ }
+
+ switch (rep->req_type) {
+ case DP_LINK_ADDRESS: {
+ struct drm_dp_link_address_ack_reply *link_addr = &rep->u.link_addr;
+ struct drm_dp_link_addr_reply_port *port;
+
+ memcpy(&buf[idx], link_addr->guid, 16);
+ idx += 16;
+ buf[idx++] = link_addr->nports;
+ for (i = 0; i < link_addr->nports; i++) {
+ port = &link_addr->ports[i];
+ buf[idx++] = port->input_port << 7 | port->peer_device_type << 4 |
+ port->port_number;
+ if (port->input_port == 0) {
+ buf[idx++] = port->mcs << 7 | port->ddps << 6 |
+ port->legacy_device_plug_status << 5;
+ buf[idx++] = port->dpcd_revision;
+ memcpy(&buf[idx], port->peer_guid, 16);
+ idx += 16;
+ buf[idx++] = port->num_sdp_streams << 4 |
+ port->num_sdp_stream_sinks;
+ } else {
+ buf[idx++] = port->mcs << 7 | port->ddps << 6;
+ }
+ }
+ break;
+ }
+ case DP_ENUM_PATH_RESOURCES: {
+ struct drm_dp_enum_path_resources_ack_reply *path_res = &rep->u.path_resources;
+
+ buf[idx++] = path_res->port_number << 4 | path_res->fec_capable;
+ buf[idx++] = path_res->full_payload_bw_number >> 8;
+ buf[idx++] = path_res->full_payload_bw_number & 0xff;
+ buf[idx++] = path_res->avail_payload_bw_number >> 8;
+ buf[idx++] = path_res->avail_payload_bw_number & 0xff;
+ break;
+ }
+ case DP_ALLOCATE_PAYLOAD: {
+ struct drm_dp_allocate_payload_ack_reply *alloc_payload = &rep->u.allocate_payload;
+
+ buf[idx++] = alloc_payload->port_number << 4;
+ buf[idx++] = alloc_payload->vcpi & 0x3f;
+ buf[idx++] = alloc_payload->allocated_pbn >> 8;
+ buf[idx++] = alloc_payload->allocated_pbn & 0xff;
+ break;
+ }
+ case DP_REMOTE_DPCD_READ: {
+ struct drm_dp_remote_dpcd_read_ack_reply *dpcd_read = &rep->u.remote_dpcd_read_ack;
+
+ buf[idx++] = dpcd_read->port_number & 0xf;
+ buf[idx++] = dpcd_read->num_bytes;
+ memcpy(&buf[idx], dpcd_read->bytes, dpcd_read->num_bytes);
+ idx += dpcd_read->num_bytes;
+ break;
+ }
+ case DP_REMOTE_I2C_READ: {
+ struct drm_dp_remote_i2c_read_ack_reply *i2c_read = &rep->u.remote_i2c_read_ack;
+
+ buf[idx++] = i2c_read->port_number & 0xf;
+ buf[idx++] = i2c_read->num_bytes;
+ memcpy(&buf[idx], i2c_read->bytes, i2c_read->num_bytes);
+ idx += i2c_read->num_bytes;
+ break;
+ }
+ case DP_REMOTE_I2C_WRITE:
+ buf[idx++] = rep->u.remote_i2c_write_ack.port_number & 0xf;
+ break;
+ case DP_POWER_UP_PHY:
+ case DP_POWER_DOWN_PHY:
+ buf[idx++] = rep->u.port_number.port_number << 4;
+ break;
+ }
+ *len = idx;
+}
+
+static void dprx_execute_msg_transaction(struct dprx *dprx,
+ struct drm_dp_sideband_msg_req_body *req,
+ struct drm_dp_sideband_msg_reply_body *rep)
+{
+ switch (req->req_type) {
+ case DP_LINK_ADDRESS:
+ dprx_execute_link_address(dprx, req, rep);
+ break;
+ case DP_CONNECTION_STATUS_NOTIFY:
+ dprx_execute_connection_status_notify(dprx, req, rep);
+ break;
+ case DP_ENUM_PATH_RESOURCES:
+ dprx_execute_enum_path_resources(dprx, req, rep);
+ break;
+ case DP_ALLOCATE_PAYLOAD:
+ dprx_execute_allocate_payload(dprx, req, rep);
+ break;
+ case DP_CLEAR_PAYLOAD_ID_TABLE:
+ dprx_execute_clear_payload_id_table(dprx, req, rep);
+ break;
+ case DP_REMOTE_DPCD_READ:
+ dprx_execute_remote_dpcd_read(dprx, req, rep);
+ break;
+ case DP_REMOTE_I2C_READ:
+ dprx_execute_remote_i2c_read(dprx, req, rep);
+ break;
+ case DP_REMOTE_I2C_WRITE:
+ dprx_execute_remote_i2c_write(dprx, req, rep);
+ break;
+ case DP_POWER_UP_PHY:
+ dprx_execute_power_up_phy(dprx, req, rep);
+ break;
+ case DP_POWER_DOWN_PHY:
+ dprx_execute_power_down_phy(dprx, req, rep);
+ break;
+ default:
+ dprx_write_nak(dprx, rep, req->req_type, DP_NAK_BAD_PARAM);
+ break;
+ }
+}
+
+static void dprx_handle_msg_transaction(struct dprx *dprx,
+ struct msg_transaction_rxbuf *rxbuf,
+ struct msg_transaction_txbuf *txbuf)
+{
+ bool decoded;
+ struct drm_dp_sideband_msg_req_body req;
+ struct drm_dp_sideband_msg_reply_body rep;
+
+ decoded = dprx_decode_sideband_req(&req, rxbuf->buf, rxbuf->len);
+ if (decoded)
+ dprx_execute_msg_transaction(dprx, &req, &rep);
+ else
+ dprx_write_nak(dprx, &rep, req.req_type, DP_NAK_BAD_PARAM);
+ dprx_encode_sideband_rep(&rep, txbuf->buf, &txbuf->len);
+ txbuf->written = 0;
+}
+
+static void dprx_msg_transaction_append(struct msg_transaction_rxbuf *rxbuf,
+ struct msg_transaction_meta *meta,
+ struct sideband_msg *msg)
+{
+ int append_len;
+
+ append_len = min(msg->body_len, sizeof(rxbuf->buf) - rxbuf->len);
+ memcpy(rxbuf->buf + rxbuf->len, msg->body, append_len);
+ rxbuf->len += append_len;
+
+ if (msg->somt) {
+ meta->lct = msg->lct;
+ memcpy(meta->rad, msg->rad, msg->lct / 2);
+ meta->seqno = msg->seqno;
+ }
+}
+
+static void dprx_msg_transaction_extract(struct msg_transaction_txbuf *txbuf,
+ struct msg_transaction_meta *meta,
+ struct sideband_msg *msg)
+{
+ int hdr_len = 3 + meta->lct / 2;
+ int body_len;
+ bool somt;
+ bool eomt;
+
+ body_len = txbuf->len - txbuf->written;
+ /* trim body_len so that the sideband msg fits into 48 bytes */
+ body_len = min(body_len, 48 - 1 - hdr_len);
+
+ somt = (txbuf->written == 0);
+ eomt = (txbuf->written + body_len == txbuf->len);
+
+ msg->lct = meta->lct;
+ msg->lcr = meta->lct - 1;
+ memcpy(msg->rad, meta->rad, meta->lct / 2);
+ msg->broadcast = false;
+ msg->path_msg = false;
+ msg->somt = somt;
+ msg->eomt = eomt;
+ msg->seqno = meta->seqno;
+
+ memcpy(msg->body, txbuf->buf + txbuf->written, body_len);
+ msg->body_len = body_len;
+
+ txbuf->written += body_len;
+}
+
+static void dprx_msg_transaction_clear_rxbuf(struct msg_transaction_rxbuf *rxbuf)
+{
+ rxbuf->len = 0;
+}
+
+static void dprx_msg_transaction_clear_txbuf(struct msg_transaction_txbuf *txbuf)
+{
+ txbuf->len = 0;
+ txbuf->written = 0;
+}
+
+static bool dprx_msg_transaction_txbuf_empty(struct msg_transaction_txbuf *txbuf)
+{
+ return txbuf->written == txbuf->len;
+}
+
+static void dprx_write_pending_sideband_msg(struct dprx *dprx)
+{
+ struct msg_transaction_txbuf *txbuf;
+ struct msg_transaction_meta *meta;
+ struct sideband_msg msg;
+
+ if (WARN_ON_ONCE(!dprx->mt_pending))
+ return;
+
+ txbuf = &dprx->mt_txbuf[dprx->mt_seqno];
+ meta = &dprx->mt_meta[dprx->mt_seqno];
+
+ dprx_msg_transaction_extract(txbuf, meta, &msg);
+ if (dprx_msg_transaction_txbuf_empty(txbuf)) {
+ dprx->mt_seqno = !dprx->mt_seqno;
+ txbuf = &dprx->mt_txbuf[dprx->mt_seqno];
+ if (dprx_msg_transaction_txbuf_empty(txbuf))
+ dprx->mt_pending = false;
+ }
+
+ dprx_encode_sideband_msg(&msg, dprx->down_rep_buf);
+}
+
+static void dprx_signal_irq(struct dprx *dprx, int irq)
+{
+ dprx->irq_vector |= irq;
+ dprx_pulse_hpd(dprx);
+}
+
+static void dprx_handle_sideband_msg(struct dprx *dprx, struct sideband_msg *msg)
+{
+ struct msg_transaction_rxbuf *rxbuf = &dprx->mt_rxbuf[msg->seqno];
+ struct msg_transaction_txbuf *txbuf = &dprx->mt_txbuf[msg->seqno];
+ struct msg_transaction_meta *meta = &dprx->mt_meta[msg->seqno];
+
+ if (msg->somt)
+ dprx_msg_transaction_clear_rxbuf(rxbuf);
+ dprx_msg_transaction_append(rxbuf, meta, msg);
+
+ if (msg->eomt) {
+ /* drop the message if txbuf isn't empty */
+ if (!dprx_msg_transaction_txbuf_empty(txbuf))
+ return;
+ dprx_handle_msg_transaction(dprx, rxbuf, txbuf);
+
+ if (!dprx->mt_pending) {
+ dprx->mt_pending = true;
+ dprx->mt_seqno = msg->seqno;
+ if (!dprx->down_rep_pending) {
+ dprx_write_pending_sideband_msg(dprx);
+ dprx_signal_irq(dprx, DP_DOWN_REP_MSG_RDY);
+ dprx->down_rep_pending = true;
+ }
+ }
+ }
+}
+
+static void dprx_init_caps(struct dprx *dprx)
+{
+ memset(dprx->caps, 0, sizeof(dprx->caps));
+ dprx->caps[DP_DPCD_REV] = DP_DPCD_REV_14;
+ dprx->caps[DP_MAX_LINK_RATE] = dprx->max_link_rate;
+ dprx->caps[DP_MAX_LANE_COUNT] = DP_ENHANCED_FRAME_CAP | DP_TPS3_SUPPORTED |
+ dprx->max_lane_count;
+ dprx->caps[DP_MAX_DOWNSPREAD] = DP_TPS4_SUPPORTED | DP_MAX_DOWNSPREAD_0_5;
+ dprx->caps[DP_MAIN_LINK_CHANNEL_CODING] = DP_CAP_ANSI_8B10B;
+ dprx->caps[DP_RECEIVE_PORT_0_CAP_0] = DP_LOCAL_EDID_PRESENT;
+}
+
+static u8 dprx_read_caps(struct dprx *dprx, u32 offset)
+{
+ return dprx->caps[offset];
+}
+
+static u8 dprx_read_mstm_cap(struct dprx *dprx)
+{
+ return dprx->multi_stream_support;
+}
+
+static u8 dprx_read_guid(struct dprx *dprx, u32 offset)
+{
+ return dprx->guid[offset];
+}
+
+static void dprx_write_guid(struct dprx *dprx, u32 offset, u8 val)
+{
+ dprx->guid[offset] = val;
+}
+
+static u8 dprx_read_link_bw(struct dprx *dprx)
+{
+ u32 reg = dprx_read(dprx, DPRX_RX_CONTROL);
+
+ return (reg >> DPRX_RX_CONTROL_LINK_RATE_SHIFT) & DPRX_RX_CONTROL_LINK_RATE_MASK;
+}
+
+static void dprx_write_link_bw(struct dprx *dprx, u8 val)
+{
+ u32 reg;
+
+ if (val != DP_LINK_BW_1_62 && val != DP_LINK_BW_2_7 &&
+ val != DP_LINK_BW_5_4 && val != DP_LINK_BW_8_1)
+ return;
+
+ if (val > dprx->max_link_rate)
+ return;
+
+ reg = dprx_read(dprx, DPRX_RX_CONTROL);
+ reg &= ~(DPRX_RX_CONTROL_LINK_RATE_MASK << DPRX_RX_CONTROL_LINK_RATE_SHIFT);
+ reg |= val << DPRX_RX_CONTROL_LINK_RATE_SHIFT;
+ reg |= 1 << DPRX_RX_CONTROL_RECONFIG_LINKRATE;
+ dprx_write(dprx, DPRX_RX_CONTROL, reg);
+}
+
+static u8 dprx_read_lane_count(struct dprx *dprx)
+{
+ u32 reg = dprx_read(dprx, DPRX_RX_CONTROL);
+
+ return (reg >> DPRX_RX_CONTROL_LANE_COUNT_SHIFT) & DPRX_RX_CONTROL_LANE_COUNT_MASK;
+}
+
+static void dprx_write_lane_count(struct dprx *dprx, u8 val)
+{
+ u32 reg;
+ u8 lane_count;
+
+ lane_count = val & DP_LANE_COUNT_MASK;
+
+ if (lane_count != 1 && lane_count != 2 && lane_count != 4)
+ return;
+
+ if (lane_count > dprx->max_lane_count)
+ return;
+
+ reg = dprx_read(dprx, DPRX_RX_CONTROL);
+ reg &= ~(DPRX_RX_CONTROL_LANE_COUNT_MASK << DPRX_RX_CONTROL_LANE_COUNT_SHIFT);
+ reg |= lane_count << DPRX_RX_CONTROL_LANE_COUNT_SHIFT;
+ dprx_write(dprx, DPRX_RX_CONTROL, reg);
+}
+
+static u8 dprx_read_training_pattern(struct dprx *dprx)
+{
+ u32 reg;
+ u32 pattern;
+ u32 scrambler_disable;
+ u8 result = 0;
+
+ reg = dprx_read(dprx, DPRX_RX_CONTROL);
+ pattern = (reg >> DPRX_RX_CONTROL_TP_SHIFT) & DPRX_RX_CONTROL_TP_MASK;
+ scrambler_disable = (reg >> DPRX_RX_CONTROL_SCRAMBLER_DISABLE) & 1;
+
+ if (scrambler_disable)
+ result |= DP_LINK_SCRAMBLING_DISABLE;
+ result |= pattern;
+
+ return result;
+}
+
+static void dprx_write_training_pattern(struct dprx *dprx, u8 val)
+{
+ u8 pattern;
+ u8 scrambler_disable;
+ u32 reg;
+
+ pattern = val & DP_TRAINING_PATTERN_MASK_1_4;
+ scrambler_disable = !!(val & DP_LINK_SCRAMBLING_DISABLE);
+
+ reg = dprx_read(dprx, DPRX_RX_CONTROL);
+ reg &= ~(DPRX_RX_CONTROL_TP_MASK << DPRX_RX_CONTROL_TP_SHIFT);
+ reg |= pattern << DPRX_RX_CONTROL_TP_SHIFT;
+ reg &= ~(1 << DPRX_RX_CONTROL_SCRAMBLER_DISABLE);
+ reg |= scrambler_disable << DPRX_RX_CONTROL_SCRAMBLER_DISABLE;
+ dprx_write(dprx, DPRX_RX_CONTROL, reg);
+}
+
+static u8 dprx_read_training_lane(struct dprx *dprx, u32 offset)
+{
+ struct dprx_training_control *ctl = &dprx->training_control[offset];
+ u8 result = 0;
+
+ result |= ctl->volt_swing << DP_TRAIN_VOLTAGE_SWING_SHIFT;
+ if (ctl->max_swing)
+ result |= DP_TRAIN_MAX_SWING_REACHED;
+ result |= ctl->pre_emph << DP_TRAIN_PRE_EMPHASIS_SHIFT;
+ if (ctl->max_pre_emph)
+ result |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
+
+ return result;
+}
+
+static void dprx_write_training_lane(struct dprx *dprx, u32 offset, u8 val)
+{
+ struct dprx_training_control *ctl = &dprx->training_control[offset];
+
+ ctl->volt_swing = (val & DP_TRAIN_VOLTAGE_SWING_MASK) >> DP_TRAIN_VOLTAGE_SWING_SHIFT;
+ ctl->max_swing = (val & DP_TRAIN_MAX_SWING_REACHED);
+ ctl->pre_emph = (val & DP_TRAIN_PRE_EMPHASIS_MASK) >> DP_TRAIN_PRE_EMPHASIS_SHIFT;
+ ctl->max_pre_emph = (val & DP_TRAIN_MAX_PRE_EMPHASIS_REACHED);
+}
+
+static u8 dprx_read_mstm_ctrl(struct dprx *dprx)
+{
+ return (dprx_read(dprx, DPRX_MST_CONTROL1) >> DPRX_MST_CONTROL1_MST_EN) & 1;
+}
+
+static void dprx_write_mstm_ctrl(struct dprx *dprx, u8 val)
+{
+ u8 mst_en = !!(val & DP_MST_EN);
+ u32 reg;
+
+ reg = dprx_read(dprx, DPRX_MST_CONTROL1);
+ reg &= ~(1 << DPRX_MST_CONTROL1_MST_EN);
+ reg |= mst_en << DPRX_MST_CONTROL1_MST_EN;
+ dprx_write(dprx, DPRX_MST_CONTROL1, reg);
+}
+
+static void dprx_handle_payload_allocate(struct dprx *dprx)
+{
+ u8 id = dprx->payload_allocate_set;
+ u8 start = dprx->payload_allocate_start_time_slot;
+ u8 count = dprx->payload_allocate_time_slot_count;
+
+ if (id == 0 && start == 0 && count == 0x3f) {
+ dprx_clear_vc_payload_table(dprx);
+ } else {
+ if (count == 0)
+ dprx_deallocate_vc_payload(dprx, start, id);
+ else
+ dprx_allocate_vc_payload(dprx, start, count, id);
+ dprx_set_vc_payload_table(dprx);
+ }
+ dprx->payload_table_updated = 1;
+}
+
+static u8 dprx_read_payload_allocate_set(struct dprx *dprx)
+{
+ return dprx->payload_allocate_set;
+}
+
+static void dprx_write_payload_allocate_set(struct dprx *dprx, u8 val)
+{
+ dprx->payload_allocate_set = val & DP_PAYLOAD_ALLOCATE_SET_MASK;
+}
+
+static u8 dprx_read_payload_allocate_start_time_slot(struct dprx *dprx)
+{
+ return dprx->payload_allocate_start_time_slot;
+}
+
+static void dprx_write_payload_allocate_start_time_slot(struct dprx *dprx, u8 val)
+{
+ dprx->payload_allocate_start_time_slot = val & DP_PAYLOAD_ALLOCATE_START_TIME_SLOT_MASK;
+}
+
+static u8 dprx_read_payload_allocate_time_slot_count(struct dprx *dprx)
+{
+ return dprx->payload_allocate_time_slot_count;
+}
+
+static void dprx_write_payload_allocate_time_slot_count(struct dprx *dprx, u8 val)
+{
+ dprx->payload_allocate_time_slot_count = val & DP_PAYLOAD_ALLOCATE_TIME_SLOT_COUNT_MASK;
+ dprx_handle_payload_allocate(dprx);
+}
+
+static u8 dprx_read_sink_count(struct dprx *dprx)
+{
+ return dprx->max_stream_count;
+}
+
+static u8 dprx_read_device_service_irq_vector(struct dprx *dprx)
+{
+ return dprx->irq_vector;
+}
+
+static void dprx_write_device_service_irq_vector(struct dprx *dprx, u8 val)
+{
+ dprx->irq_vector &= ~val;
+
+ if (val & DP_DOWN_REP_MSG_RDY) {
+ if (dprx->mt_pending) {
+ dprx_write_pending_sideband_msg(dprx);
+ dprx_signal_irq(dprx, DP_DOWN_REP_MSG_RDY);
+ } else {
+ dprx->down_rep_pending = false;
+ }
+ }
+}
+
+static u8 dprx_read_lane0_1_status(struct dprx *dprx)
+{
+ u32 reg;
+ u8 res = 0;
+
+ reg = dprx_read(dprx, DPRX_RX_STATUS);
+ if ((reg >> DPRX_RX_STATUS_CR_LOCK(0)) & 1)
+ res |= DP_LANE_CR_DONE;
+ if ((reg >> DPRX_RX_STATUS_CR_LOCK(1)) & 1)
+ res |= DP_LANE_CR_DONE << 4;
+ if ((reg >> DPRX_RX_STATUS_SYM_LOCK(0)) & 1)
+ res |= DP_LANE_CHANNEL_EQ_DONE | DP_LANE_SYMBOL_LOCKED;
+ if ((reg >> DPRX_RX_STATUS_SYM_LOCK(1)) & 1)
+ res |= (DP_LANE_CHANNEL_EQ_DONE | DP_LANE_SYMBOL_LOCKED) << 4;
+
+ return res;
+}
+
+static u8 dprx_read_lane2_3_status(struct dprx *dprx)
+{
+ u32 reg;
+ u8 res = 0;
+
+ reg = dprx_read(dprx, DPRX_RX_STATUS);
+ if ((reg >> DPRX_RX_STATUS_CR_LOCK(2)) & 1)
+ res |= DP_LANE_CR_DONE;
+ if ((reg >> DPRX_RX_STATUS_CR_LOCK(3)) & 1)
+ res |= DP_LANE_CR_DONE << 4;
+ if ((reg >> DPRX_RX_STATUS_SYM_LOCK(2)) & 1)
+ res |= DP_LANE_CHANNEL_EQ_DONE | DP_LANE_SYMBOL_LOCKED;
+ if ((reg >> DPRX_RX_STATUS_SYM_LOCK(3)) & 1)
+ res |= (DP_LANE_CHANNEL_EQ_DONE | DP_LANE_SYMBOL_LOCKED) << 4;
+
+ return res;
+}
+
+static u8 dprx_read_lane_align_status(struct dprx *dprx)
+{
+ return (dprx_read(dprx, DPRX_RX_STATUS) >> DPRX_RX_STATUS_INTERLANE_ALIGN) & 1;
+}
+
+static u8 dprx_read_sink_status(struct dprx *dprx)
+{
+ return (dprx_read(dprx, DPRX_VBID(0)) >> DPRX_VBID_MSA_LOCK) & 1;
+}
+
+static u8 dprx_read_adjust_request(struct dprx *dprx,
+ struct dprx_training_control *ctl0,
+ struct dprx_training_control *ctl1)
+{
+ u8 next_volt_swing0;
+ u8 next_pre_emph0;
+ u8 next_volt_swing1;
+ u8 next_pre_emph1;
+
+ if (dprx_adjust_needed(dprx)) {
+ dprx_training_control_next(ctl0, &next_volt_swing0, &next_pre_emph0);
+ dprx_training_control_next(ctl1, &next_volt_swing1, &next_pre_emph1);
+ } else {
+ next_volt_swing0 = ctl0->volt_swing;
+ next_pre_emph0 = ctl0->pre_emph;
+ next_volt_swing1 = ctl1->volt_swing;
+ next_pre_emph1 = ctl1->pre_emph;
+ }
+
+ return next_volt_swing0 << DP_ADJUST_VOLTAGE_SWING_LANE0_SHIFT |
+ next_pre_emph0 << DP_ADJUST_PRE_EMPHASIS_LANE0_SHIFT |
+ next_volt_swing1 << DP_ADJUST_VOLTAGE_SWING_LANE1_SHIFT |
+ next_pre_emph1 << DP_ADJUST_PRE_EMPHASIS_LANE1_SHIFT;
+}
+
+static u8 dprx_read_adjust_request_lane0_1(struct dprx *dprx)
+{
+ return dprx_read_adjust_request(dprx,
+ &dprx->training_control[0],
+ &dprx->training_control[1]);
+}
+
+static u8 dprx_read_adjust_request_lane2_3(struct dprx *dprx)
+{
+ return dprx_read_adjust_request(dprx,
+ &dprx->training_control[2],
+ &dprx->training_control[3]);
+}
+
+static u8 dprx_read_payload_table_update_status(struct dprx *dprx)
+{
+ u32 reg;
+ u32 act_handled;
+ u8 result = 0;
+
+ reg = dprx_read(dprx, DPRX_MST_STATUS1);
+ act_handled = (reg >> DPRX_MST_STATUS1_VCPTAB_ACT_ACK) & 1;
+
+ if (dprx->payload_table_updated)
+ result |= DP_PAYLOAD_TABLE_UPDATED;
+ if (act_handled)
+ result |= DP_PAYLOAD_ACT_HANDLED;
+
+ return result;
+}
+
+static void dprx_write_payload_table_update_status(struct dprx *dprx, u8 val)
+{
+ u32 reg;
+
+ if (val & DP_PAYLOAD_TABLE_UPDATED) {
+ dprx->payload_table_updated = 0;
+ reg = dprx_read(dprx, DPRX_MST_CONTROL1);
+ reg &= ~(1 << DPRX_MST_CONTROL1_VCPTAB_UPD_REQ);
+ dprx_write(dprx, DPRX_MST_CONTROL1, reg);
+ }
+}
+
+static u8 dprx_read_vc_payload_id_slot(struct dprx *dprx, u32 offset)
+{
+ return dprx->payload_table[offset + 1];
+}
+
+static u8 dprx_read_down_req(struct dprx *dprx, u32 offset)
+{
+ return dprx->down_req_buf[offset];
+}
+
+static void dprx_write_down_req(struct dprx *dprx, u32 offset, u8 val)
+{
+ struct sideband_msg msg;
+
+ dprx->down_req_buf[offset] = val;
+ if (dprx_decode_sideband_msg(&msg, dprx->down_req_buf, offset + 1))
+ dprx_handle_sideband_msg(dprx, &msg);
+}
+
+static u8 dprx_read_down_rep(struct dprx *dprx, u32 offset)
+{
+ return dprx->down_rep_buf[offset];
+}
+
+struct dprx_dpcd_handler {
+ u32 addr;
+ u32 range_len;
+ union {
+ u8 (*point)(struct dprx *dprx);
+ u8 (*range)(struct dprx *dprx, u32 offset);
+ } read;
+ union {
+ void (*point)(struct dprx *dprx, u8 val);
+ void (*range)(struct dprx *dprx, u32 offset, u8 val);
+ } write;
+};
+
+static void dprx_write_noop(struct dprx *dprx, u8 val)
+{
+}
+
+static void dprx_write_noop_range(struct dprx *dprx, u32 offset, u8 val)
+{
+}
+
+static struct dprx_dpcd_handler dprx_dpcd_handlers[] = {
+ { 0x00000, 16, { .range = dprx_read_caps },
+ { .range = dprx_write_noop_range } },
+ { 0x00021, 0, { .point = dprx_read_mstm_cap },
+ { .point = dprx_write_noop } },
+ { 0x00030, 16, { .range = dprx_read_guid },
+ { .range = dprx_write_guid } },
+ { 0x00100, 0, { .point = dprx_read_link_bw },
+ { .point = dprx_write_link_bw } },
+ { 0x00101, 0, { .point = dprx_read_lane_count },
+ { .point = dprx_write_lane_count } },
+ { 0x00102, 0, { .point = dprx_read_training_pattern },
+ { .point = dprx_write_training_pattern } },
+ { 0x00103, 4, { .range = dprx_read_training_lane },
+ { .range = dprx_write_training_lane } },
+ { 0x00111, 0, { .point = dprx_read_mstm_ctrl },
+ { .point = dprx_write_mstm_ctrl } },
+ { 0x001c0, 0, { .point = dprx_read_payload_allocate_set },
+ { .point = dprx_write_payload_allocate_set } },
+ { 0x001c1, 0, { .point = dprx_read_payload_allocate_start_time_slot },
+ { .point = dprx_write_payload_allocate_start_time_slot } },
+ { 0x001c2, 0, { .point = dprx_read_payload_allocate_time_slot_count },
+ { .point = dprx_write_payload_allocate_time_slot_count } },
+ { 0x00200, 0, { .point = dprx_read_sink_count },
+ { .point = dprx_write_noop } },
+ { 0x00201, 0, { .point = dprx_read_device_service_irq_vector },
+ { .point = dprx_write_device_service_irq_vector } },
+ { 0x00202, 0, { .point = dprx_read_lane0_1_status },
+ { .point = dprx_write_noop } },
+ { 0x00203, 0, { .point = dprx_read_lane2_3_status },
+ { .point = dprx_write_noop } },
+ { 0x00204, 0, { .point = dprx_read_lane_align_status },
+ { .point = dprx_write_noop } },
+ { 0x00205, 0, { .point = dprx_read_sink_status },
+ { .point = dprx_write_noop } },
+ { 0x00206, 0, { .point = dprx_read_adjust_request_lane0_1 },
+ { .point = dprx_write_noop } },
+ { 0x00207, 0, { .point = dprx_read_adjust_request_lane2_3 },
+ { .point = dprx_write_noop } },
+ { 0x002c0, 0, { .point = dprx_read_payload_table_update_status },
+ { .point = dprx_write_payload_table_update_status } },
+ { 0x002c1, 63, { .range = dprx_read_vc_payload_id_slot },
+ { .range = dprx_write_noop_range } },
+ { 0x01000, 48, { .range = dprx_read_down_req },
+ { .range = dprx_write_down_req } },
+ { 0x01400, 48, { .range = dprx_read_down_rep },
+ { .range = dprx_write_noop_range } },
+ /* Event Status Indicator is a copy of 200h - 205h */
+ { 0x02002, 0, { .point = dprx_read_sink_count },
+ { .point = dprx_write_noop } },
+ { 0x02003, 0, { .point = dprx_read_device_service_irq_vector },
+ { .point = dprx_write_device_service_irq_vector } },
+ { 0x0200c, 0, { .point = dprx_read_lane0_1_status },
+ { .point = dprx_write_noop } },
+ { 0x0200d, 0, { .point = dprx_read_lane2_3_status },
+ { .point = dprx_write_noop } },
+ { 0x0200e, 0, { .point = dprx_read_lane_align_status },
+ { .point = dprx_write_noop } },
+ { 0x0200f, 0, { .point = dprx_read_sink_status },
+ { .point = dprx_write_noop } },
+ /* Extended Receiver Capability is a copy of 0h - 0fh */
+ { 0x02200, 16, { .range = dprx_read_caps },
+ { .range = dprx_write_noop_range } },
+};
+
+static bool dprx_dpcd_handler_match(struct dprx_dpcd_handler *handler, u32 addr)
+{
+ if (handler->range_len == 0)
+ return addr == handler->addr;
+ else
+ return addr >= handler->addr && addr < handler->addr + handler->range_len;
+}
+
+static void dprx_dpcd_handler_run(struct dprx_dpcd_handler *handler,
+ struct dprx *dprx, u32 addr, u8 *val, bool read)
+{
+ if (read) {
+ if (handler->range_len == 0)
+ *val = handler->read.point(dprx);
+ else
+ *val = handler->read.range(dprx, addr - handler->addr);
+ } else {
+ if (handler->range_len == 0)
+ handler->write.point(dprx, *val);
+ else
+ handler->write.range(dprx, addr - handler->addr, *val);
+ }
+}
+
+static void dprx_dpcd_access(struct dprx *dprx, u32 addr, u8 *val, bool read)
+{
+ struct dprx_dpcd_handler *handler;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dprx_dpcd_handlers); i++) {
+ handler = &dprx_dpcd_handlers[i];
+ if (dprx_dpcd_handler_match(handler, addr)) {
+ dprx_dpcd_handler_run(handler, dprx, addr, val, read);
+ return;
+ }
+ }
+
+ /* for unsupported registers, writes are ignored and reads return 0. */
+ if (read)
+ *val = 0;
+}
+
+static void dprx_handle_native_aux(struct dprx *dprx, struct aux_msg *req, struct aux_msg *rep)
+{
+ bool read = req->cmd & 1;
+ u8 *data;
+ int i;
+
+ rep->cmd = DP_AUX_NATIVE_REPLY_ACK;
+ if (read) {
+ rep->len = req->len;
+ data = rep->data;
+ } else {
+ rep->len = 0;
+ data = req->data;
+ }
+
+ for (i = 0; i < req->len; i++)
+ dprx_dpcd_access(dprx, req->addr + i, data + i, read);
+}
+
+static void dprx_handle_i2c_read(struct dprx *dprx, struct aux_msg *req, struct aux_msg *rep)
+{
+ int res;
+
+ res = dprx_i2c_read(&dprx->sinks[0], req->addr, rep->data, req->len);
+ if (!res) {
+ rep->cmd = DP_AUX_I2C_REPLY_ACK;
+ rep->len = req->len;
+ } else {
+ rep->cmd = DP_AUX_I2C_REPLY_NACK;
+ rep->len = 0;
+ }
+}
+
+static void dprx_handle_i2c_write(struct dprx *dprx, struct aux_msg *req, struct aux_msg *rep)
+{
+ int res;
+
+ res = dprx_i2c_write(&dprx->sinks[0], req->addr, req->data, req->len);
+ if (!res)
+ rep->cmd = DP_AUX_I2C_REPLY_ACK;
+ else
+ rep->cmd = DP_AUX_I2C_REPLY_NACK;
+ rep->len = 0;
+}
+
+static void dprx_decode_aux_request(struct aux_msg *req, struct aux_buf *buf)
+{
+ req->cmd = buf->data[0] >> 4;
+ req->addr = (buf->data[0] & 0xf) << 16 | buf->data[1] << 8 | buf->data[2];
+ if (buf->len < 4) {
+ req->len = 0;
+ } else {
+ req->len = buf->data[3] + 1;
+ memcpy(req->data, &buf->data[4], req->len);
+ }
+}
+
+static void dprx_encode_aux_reply(struct aux_msg *rep, struct aux_buf *buf)
+{
+ buf->data[0] = rep->cmd << 4;
+ memcpy(&buf->data[1], rep->data, rep->len);
+ buf->len = rep->len + 1;
+}
+
+static void dprx_handle_aux(struct dprx *dprx, struct aux_buf *req_buf, struct aux_buf *rep_buf)
+{
+ struct aux_msg req;
+ struct aux_msg rep;
+
+ dprx_decode_aux_request(&req, req_buf);
+
+ if (req.cmd & 8) {
+ dprx_handle_native_aux(dprx, &req, &rep);
+ } else {
+ if (req.cmd & 1)
+ dprx_handle_i2c_read(dprx, &req, &rep);
+ else
+ dprx_handle_i2c_write(dprx, &req, &rep);
+ if (!(req.cmd & DP_AUX_I2C_MOT))
+ dprx_i2c_stop(&dprx->sinks[0]);
+ }
+
+ dprx_encode_aux_reply(&rep, rep_buf);
+}
+
+static int dprx_read_aux(struct dprx *dprx, struct aux_buf *buf)
+{
+ u32 control = dprx_read(dprx, DPRX_AUX_CONTROL);
+ int i;
+
+ /* check MSG_READY */
+ if (!((dprx_read(dprx, DPRX_AUX_STATUS) >> DPRX_AUX_STATUS_MSG_READY) & 1))
+ return -1;
+
+ /* read LENGTH */
+ buf->len = (control >> DPRX_AUX_CONTROL_LENGTH_SHIFT) & DPRX_AUX_CONTROL_LENGTH_MASK;
+ if (buf->len > 20)
+ buf->len = 20;
+
+ /* read request */
+ for (i = 0; i < buf->len; i++)
+ buf->data[i] = dprx_read(dprx, DPRX_AUX_COMMAND + i);
+
+ return 0;
+}
+
+static void dprx_write_aux(struct dprx *dprx, struct aux_buf *buf)
+{
+ u32 reg;
+ int i;
+
+ if (!((dprx_read(dprx, DPRX_AUX_STATUS) >> DPRX_AUX_STATUS_READY_TO_TX) & 1))
+ return;
+
+ if (buf->len > 17)
+ buf->len = 17;
+ for (i = 0; i < buf->len; i++)
+ dprx_write(dprx, DPRX_AUX_COMMAND + i, buf->data[i]);
+
+ reg = dprx_read(dprx, DPRX_AUX_CONTROL);
+ reg &= ~(DPRX_AUX_CONTROL_LENGTH_MASK << DPRX_AUX_CONTROL_LENGTH_SHIFT);
+ reg |= buf->len << DPRX_AUX_CONTROL_LENGTH_SHIFT;
+ reg |= 1 << DPRX_AUX_CONTROL_TX_STROBE;
+ dprx_write(dprx, DPRX_AUX_CONTROL, reg);
+}
+
+static irqreturn_t dprx_isr(int irq, void *data)
+{
+ struct dprx *dprx = data;
+ struct aux_buf request;
+ struct aux_buf reply;
+
+ if (!dprx_read_aux(dprx, &request)) {
+ spin_lock(&dprx->lock);
+ dprx_handle_aux(dprx, &request, &reply);
+ spin_unlock(&dprx->lock);
+ dprx_write_aux(dprx, &reply);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void dprx_reset_hw(struct dprx *dprx)
+{
+ int i;
+
+ /* set link rate to 1.62 Gbps and lane count to 1 */
+ dprx_write(dprx, DPRX_RX_CONTROL,
+ DP_LINK_BW_1_62 << DPRX_RX_CONTROL_LINK_RATE_SHIFT |
+ 1 << DPRX_RX_CONTROL_RECONFIG_LINKRATE |
+ DPRX_RX_CONTROL_CHANNEL_CODING_8B10B << DPRX_RX_CONTROL_CHANNEL_CODING_SHIFT |
+ 1 << DPRX_RX_CONTROL_LANE_COUNT_SHIFT);
+ /* clear VC payload ID table */
+ for (i = 0; i < 8; i++)
+ dprx_write(dprx, DPRX_MST_VCPTAB(i), 0);
+ dprx_write(dprx, DPRX_MST_CONTROL1, 1 << DPRX_MST_CONTROL1_VCPTAB_UPD_FORCE);
+}
+
+static void dprx_reset(struct dprx *dprx)
+{
+ int i;
+
+ memset(dprx->guid, 0, sizeof(dprx->guid));
+ memset(dprx->training_control, 0, sizeof(dprx->training_control));
+
+ dprx->payload_allocate_set = 0;
+ dprx->payload_allocate_start_time_slot = 0;
+ dprx->payload_allocate_time_slot_count = 0;
+ memset(dprx->payload_table, 0, sizeof(dprx->payload_table));
+ dprx->payload_table_updated = 0;
+
+ memset(dprx->payload_id, 0, sizeof(dprx->payload_id));
+ memset(dprx->payload_pbn, 0, sizeof(dprx->payload_pbn));
+ dprx->payload_pbn_total = 0;
+
+ dprx->irq_vector = 0;
+
+ memset(dprx->down_req_buf, 0, sizeof(dprx->down_req_buf));
+ memset(dprx->down_rep_buf, 0, sizeof(dprx->down_rep_buf));
+
+ for (i = 0; i < 2; i++) {
+ dprx_msg_transaction_clear_rxbuf(&dprx->mt_rxbuf[i]);
+ dprx_msg_transaction_clear_txbuf(&dprx->mt_txbuf[i]);
+ }
+ dprx->mt_seqno = 0;
+ dprx->mt_pending = false;
+ dprx->down_rep_pending = false;
+
+ dprx_reset_hw(dprx);
+}
+
+#define to_dprx(sd) container_of(sd, struct dprx, subdev)
+
+static int dprx_get_edid(struct v4l2_subdev *sd, struct v4l2_edid *edid)
+{
+ struct dprx *dprx = to_dprx(sd);
+ struct dprx_sink *sink;
+ u32 end_block = edid->start_block + edid->blocks;
+ unsigned long flags;
+ int res = 0;
+
+ memset(edid->reserved, 0, sizeof(edid->reserved));
+
+ if (edid->pad >= dprx->max_stream_count)
+ return -EINVAL;
+
+ spin_lock_irqsave(&dprx->lock, flags);
+
+ sink = &dprx->sinks[edid->pad];
+ if (edid->start_block == 0 && edid->blocks == 0) {
+ edid->blocks = sink->blocks;
+ goto out;
+ }
+ if (sink->blocks == 0) {
+ res = -ENODATA;
+ goto out;
+ }
+ if (edid->start_block >= sink->blocks) {
+ res = -EINVAL;
+ goto out;
+ }
+ if (end_block > sink->blocks) {
+ end_block = sink->blocks;
+ edid->blocks = end_block - edid->start_block;
+ }
+
+ memcpy(edid->edid, sink->edid + edid->start_block * 128, edid->blocks * 128);
+
+out:
+ spin_unlock_irqrestore(&dprx->lock, flags);
+
+ return res;
+}
+
+static int dprx_set_edid(struct v4l2_subdev *sd, struct v4l2_edid *edid)
+{
+ struct dprx *dprx = to_dprx(sd);
+ struct dprx_sink *sink;
+ bool prev_hpd;
+ bool cur_hpd;
+ unsigned long flags;
+
+ memset(edid->reserved, 0, sizeof(edid->reserved));
+
+ if (edid->pad >= dprx->max_stream_count)
+ return -EINVAL;
+ if (edid->start_block != 0)
+ return -EINVAL;
+ if (edid->blocks > DPRX_MAX_EDID_BLOCKS) {
+ edid->blocks = DPRX_MAX_EDID_BLOCKS;
+ return -E2BIG;
+ }
+
+ spin_lock_irqsave(&dprx->lock, flags);
+ sink = &dprx->sinks[edid->pad];
+ /*
+ * This is an MST DisplayPort device, which means that one HPD
+ * line controls all the video streams. The way this is handled
+ * in s_edid is that the HPD line is controlled by the presence
+ * of only the first stream's EDID. This allows, for example, to
+ * first set the second streams's EDID and then the first one in
+ * order to reduce the amount of AUX communication.
+ */
+ prev_hpd = dprx->sinks[0].blocks > 0;
+ sink->blocks = edid->blocks;
+ memcpy(sink->edid, edid->edid, edid->blocks * 128);
+ cur_hpd = dprx->sinks[0].blocks > 0;
+ if (!prev_hpd && cur_hpd)
+ dprx_reset(dprx);
+ spin_unlock_irqrestore(&dprx->lock, flags);
+
+ if (!prev_hpd && cur_hpd) {
+ dprx_set_hpd(dprx, 1);
+ } else if (prev_hpd && !cur_hpd) {
+ dprx_set_hpd(dprx, 0);
+ } else if (prev_hpd && cur_hpd) {
+ /* HPD replug - pulse for >2ms */
+ dprx_set_hpd(dprx, 0);
+ usleep_range(2000, 4000);
+ dprx_set_hpd(dprx, 1);
+ }
+
+ return 0;
+}
+
+static int dprx_query_dv_timings(struct v4l2_subdev *sd, unsigned int pad,
+ struct v4l2_dv_timings *timings)
+{
+ struct dprx *dprx = to_dprx(sd);
+ u32 htotal, vtotal;
+ u32 hsp, hsw;
+ u32 hstart, vstart;
+ u32 vsp, vsw;
+ u32 hwidth, vheight;
+
+ if (pad >= dprx->max_stream_count)
+ return -EINVAL;
+
+ if (!((dprx_read(dprx, DPRX_VBID(pad)) >> DPRX_VBID_MSA_LOCK) & 1))
+ return -ENOLINK;
+
+ htotal = dprx_read(dprx, DPRX_MSA_HTOTAL(pad));
+ vtotal = dprx_read(dprx, DPRX_MSA_VTOTAL(pad));
+ hsp = dprx_read(dprx, DPRX_MSA_HSP(pad));
+ hsw = dprx_read(dprx, DPRX_MSA_HSW(pad));
+ hstart = dprx_read(dprx, DPRX_MSA_HSTART(pad));
+ vstart = dprx_read(dprx, DPRX_MSA_VSTART(pad));
+ vsp = dprx_read(dprx, DPRX_MSA_VSP(pad));
+ vsw = dprx_read(dprx, DPRX_MSA_VSW(pad));
+ hwidth = dprx_read(dprx, DPRX_MSA_HWIDTH(pad));
+ vheight = dprx_read(dprx, DPRX_MSA_VHEIGHT(pad));
+
+ memset(timings, 0, sizeof(*timings));
+ timings->type = V4L2_DV_BT_656_1120;
+ timings->bt.width = hwidth;
+ timings->bt.height = vheight;
+ timings->bt.polarities = (!vsp) | (!hsp) << 1;
+ timings->bt.hfrontporch = htotal - hstart - hwidth;
+ timings->bt.hsync = hsw;
+ timings->bt.hbackporch = hstart - hsw;
+ timings->bt.vfrontporch = vtotal - vstart - vheight;
+ timings->bt.vsync = vsw;
+ timings->bt.vbackporch = vstart - vsw;
+
+ return 0;
+}
+
+/* DisplayPort 1.4 capabilities */
+
+static const struct v4l2_dv_timings_cap dprx_timings_cap = {
+ .type = V4L2_DV_BT_656_1120,
+ .bt = {
+ .min_width = 0,
+ .max_width = 7680,
+ .min_height = 0,
+ .max_height = 4320,
+ .min_pixelclock = 0,
+ .max_pixelclock = 1350000000, /* 8.1Gbps * 4lanes / 24bpp */
+ .standards = V4L2_DV_BT_STD_CEA861 | V4L2_DV_BT_STD_DMT |
+ V4L2_DV_BT_STD_CVT | V4L2_DV_BT_STD_GTF,
+ .capabilities = V4L2_DV_BT_CAP_PROGRESSIVE |
+ V4L2_DV_BT_CAP_REDUCED_BLANKING |
+ V4L2_DV_BT_CAP_CUSTOM,
+ },
+};
+
+static int dprx_enum_dv_timings(struct v4l2_subdev *sd, struct v4l2_enum_dv_timings *timings)
+{
+ return v4l2_enum_dv_timings_cap(timings, &dprx_timings_cap,
+ NULL, NULL);
+}
+
+static int dprx_dv_timings_cap(struct v4l2_subdev *sd, struct v4l2_dv_timings_cap *cap)
+{
+ *cap = dprx_timings_cap;
+
+ return 0;
+}
+
+static const struct v4l2_subdev_pad_ops dprx_pad_ops = {
+ .get_edid = dprx_get_edid,
+ .set_edid = dprx_set_edid,
+ .dv_timings_cap = dprx_dv_timings_cap,
+ .enum_dv_timings = dprx_enum_dv_timings,
+ .query_dv_timings = dprx_query_dv_timings,
+};
+
+static const struct v4l2_subdev_ops dprx_subdev_ops = {
+ .pad = &dprx_pad_ops,
+};
+
+static const struct media_entity_operations dprx_entity_ops = {
+ .link_validate = v4l2_subdev_link_validate,
+ .get_fwnode_pad = v4l2_subdev_get_fwnode_pad_1_to_1,
+};
+
+static int dprx_init_pads(struct dprx *dprx)
+{
+ int i;
+
+ for (i = 0; i < dprx->max_stream_count; i++)
+ dprx->pads[i].flags = MEDIA_PAD_FL_SOURCE;
+
+ return media_entity_pads_init(&dprx->subdev.entity, dprx->max_stream_count, dprx->pads);
+}
+
+static int dprx_probe(struct platform_device *pdev)
+{
+ struct dprx *dprx;
+ int irq;
+ int res;
+
+ dprx = devm_kzalloc(&pdev->dev, sizeof(*dprx), GFP_KERNEL);
+ if (!dprx)
+ return -ENOMEM;
+ dprx->dev = &pdev->dev;
+ platform_set_drvdata(pdev, dprx);
+
+ dprx->iobase = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(dprx->iobase))
+ return PTR_ERR(dprx->iobase);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ res = devm_request_irq(dprx->dev, irq, dprx_isr, 0, "intel-dprx", dprx);
+ if (res)
+ return res;
+
+ res = device_property_read_u32(&pdev->dev, "intel,max-link-rate", &dprx->max_link_rate);
+ if (res)
+ return res;
+
+ res = device_property_read_u32(&pdev->dev, "intel,max-lane-count", &dprx->max_lane_count);
+ if (res)
+ return res;
+
+ dprx->multi_stream_support = device_property_read_bool(&pdev->dev,
+ "intel,multi-stream-support");
+
+ if (dprx->multi_stream_support) {
+ res = device_property_read_u32(&pdev->dev, "intel,max-stream-count",
+ &dprx->max_stream_count);
+ if (res)
+ return res;
+ } else {
+ dprx->max_stream_count = 1;
+ }
+
+ dprx_init_caps(dprx);
+
+ dprx->subdev.owner = THIS_MODULE;
+ dprx->subdev.dev = &pdev->dev;
+ v4l2_subdev_init(&dprx->subdev, &dprx_subdev_ops);
+ v4l2_set_subdevdata(&dprx->subdev, &pdev->dev);
+ snprintf(dprx->subdev.name, sizeof(dprx->subdev.name), "%s %s",
+ KBUILD_MODNAME, dev_name(&pdev->dev));
+ dprx->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
+
+ dprx->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
+ dprx->subdev.entity.ops = &dprx_entity_ops;
+
+ res = dprx_init_pads(dprx);
+ if (res)
+ return res;
+
+ res = v4l2_async_register_subdev(&dprx->subdev);
+ if (res)
+ return res;
+
+ dprx_set_hpd(dprx, 0);
+ dprx_reset_hw(dprx);
+
+ dprx_set_irq(dprx, 1);
+
+ return 0;
+}
+
+static void dprx_remove(struct platform_device *pdev)
+{
+ struct dprx *dprx = platform_get_drvdata(pdev);
+
+ /* disable interrupts */
+ dprx_set_irq(dprx, 0);
+
+ v4l2_async_unregister_subdev(&dprx->subdev);
+}
+
+static const struct of_device_id dprx_match_table[] = {
+ { .compatible = "intel,dprx-20.0.1" },
+ { },
+};
+
+static struct platform_driver dprx_platform_driver = {
+ .probe = dprx_probe,
+ .remove_new = dprx_remove,
+ .driver = {
+ .name = "intel-dprx",
+ .of_match_table = dprx_match_table,
+ },
+};
+
+module_platform_driver(dprx_platform_driver);
+
+MODULE_AUTHOR("Paweł Anikiel <panikiel@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Intel DisplayPort RX IP core driver");
+MODULE_LICENSE("GPL");
--
2.44.0.rc0.258.g7320e95886-goog