xref: /linux/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h (revision e0c0ab04f6785abaa71b9b8dc252cb1a2072c225)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* Copyright (c) 2024 Hisilicon Limited. */
3 
4 #ifndef DP_COMM_H
5 #define DP_COMM_H
6 
7 #include <linux/types.h>
8 #include <linux/bitops.h>
9 #include <linux/errno.h>
10 #include <linux/mutex.h>
11 #include <linux/kernel.h>
12 #include <linux/bitfield.h>
13 #include <linux/io.h>
14 #include <drm/display/drm_dp_helper.h>
15 
16 #include "dp_hw.h"
17 
18 #define HIBMC_DP_LANE_NUM_MAX 2
19 
20 struct hibmc_link_status {
21 	bool clock_recovered;
22 	bool channel_equalized;
23 };
24 
25 struct hibmc_link_cap {
26 	u8 link_rate;
27 	u8 lanes;
28 };
29 
30 struct hibmc_dp_link {
31 	struct hibmc_link_status status;
32 	u8 train_set[HIBMC_DP_LANE_NUM_MAX];
33 	struct hibmc_link_cap cap;
34 };
35 
36 struct hibmc_dp_dev {
37 	struct drm_dp_aux *aux;
38 	struct drm_device *dev;
39 	void __iomem *base;
40 	struct mutex lock; /* protects concurrent RW in hibmc_dp_reg_write_field() */
41 	struct hibmc_dp_link link;
42 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
43 	void __iomem *serdes_base;
44 };
45 
46 #define dp_field_modify(reg_value, mask, val)				\
47 	do {								\
48 		(reg_value) &= ~(mask);					\
49 		(reg_value) |= FIELD_PREP(mask, val);			\
50 	} while (0)							\
51 
52 #define hibmc_dp_reg_write_field(dp, offset, mask, val)			\
53 	do {								\
54 		typeof(dp) _dp = dp;					\
55 		typeof(_dp->base) addr = (_dp->base + (offset));	\
56 		mutex_lock(&_dp->lock);					\
57 		u32 reg_value = readl(addr);				\
58 		dp_field_modify(reg_value, mask, val);			\
59 		writel(reg_value, addr);				\
60 		mutex_unlock(&_dp->lock);				\
61 	} while (0)
62 
63 void hibmc_dp_aux_init(struct hibmc_dp *dp);
64 int hibmc_dp_link_training(struct hibmc_dp_dev *dp);
65 int hibmc_dp_serdes_init(struct hibmc_dp_dev *dp);
66 int hibmc_dp_serdes_rate_switch(u8 rate, struct hibmc_dp_dev *dp);
67 int hibmc_dp_serdes_set_tx_cfg(struct hibmc_dp_dev *dp, u8 train_set[HIBMC_DP_LANE_NUM_MAX]);
68 
69 #endif
70