1/*
2 * Copyright 2018 Advanced Micro Devices, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 *
22 * Authors: AMD
23 *
24 */
25
26#include "reg_helper.h"
27#include "core_types.h"
28#include "dcn20/dcn20_dccg.h"
29#include "dcn21_dccg.h"
30
31#define TO_DCN_DCCG(dccg)\
32 container_of(dccg, struct dcn_dccg, base)
33
34#define REG(reg) \
35 (dccg_dcn->regs->reg)
36
37#undef FN
38#define FN(reg_name, field_name) \
39 dccg_dcn->dccg_shift->field_name, dccg_dcn->dccg_mask->field_name
40
41#define CTX \
42 dccg_dcn->base.ctx
43#define DC_LOGGER \
44 dccg->ctx->logger
45
46static void dccg21_update_dpp_dto(struct dccg *dccg, int dpp_inst, int req_dppclk)
47{
48 struct dcn_dccg *dccg_dcn = TO_DCN_DCCG(dccg);
49
50 if (dccg->ref_dppclk) {
51 int ref_dppclk = dccg->ref_dppclk;
52 int modulo = ref_dppclk / 10000;
53 int phase;
54
55 if (req_dppclk) {
56 /*
57 * program DPP DTO phase and modulo as below
58 * phase = ceiling(dpp_pipe_clk_mhz / 10)
59 * module = trunc(dpp_global_clk_mhz / 10)
60 *
61 * storing frequencies in registers allow dmcub fw
62 * to run time lower clocks when possible for power saving
63 *
64 * ceiling phase and truncate modulo guarentees the divided
65 * down per pipe dpp clock has high enough frequency
66 */
67 phase = (req_dppclk + 9999) / 10000;
68
69 if (phase > modulo) {
70 /* phase > modulo result in screen corruption
71 * ie phase = 30, mod = 29 for 4k@60 HDMI
72 * in these case we don't want pipe clock to be divided
73 */
74 phase = modulo;
75 }
76 } else {
77 /*
78 * set phase to 10 if dpp isn't used to
79 * prevent hard hang if access dpp register
80 * on unused pipe
81 *
82 * DTO should be on to divide down un-used
83 * pipe clock for power saving
84 */
85 phase = 10;
86 }
87
88 REG_SET_2(DPPCLK_DTO_PARAM[dpp_inst], 0,
89 DPPCLK0_DTO_PHASE, phase,
90 DPPCLK0_DTO_MODULO, modulo);
91
92 REG_UPDATE(DPPCLK_DTO_CTRL,
93 DPPCLK_DTO_ENABLE[dpp_inst], 1);
94 }
95
96 dccg->pipe_dppclk_khz[dpp_inst] = req_dppclk;
97}
98
99
100static const struct dccg_funcs dccg21_funcs = {
101 .update_dpp_dto = dccg21_update_dpp_dto,
102 .get_dccg_ref_freq = dccg2_get_dccg_ref_freq,
103 .set_fifo_errdet_ovr_en = dccg2_set_fifo_errdet_ovr_en,
104 .otg_add_pixel = dccg2_otg_add_pixel,
105 .otg_drop_pixel = dccg2_otg_drop_pixel,
106 .dccg_init = dccg2_init
107};
108
109struct dccg *dccg21_create(
110 struct dc_context *ctx,
111 const struct dccg_registers *regs,
112 const struct dccg_shift *dccg_shift,
113 const struct dccg_mask *dccg_mask)
114{
115 struct dcn_dccg *dccg_dcn = kzalloc(size: sizeof(*dccg_dcn), GFP_KERNEL);
116 struct dccg *base;
117
118 if (dccg_dcn == NULL) {
119 BREAK_TO_DEBUGGER();
120 return NULL;
121 }
122
123 base = &dccg_dcn->base;
124 base->ctx = ctx;
125 base->funcs = &dccg21_funcs;
126
127 dccg_dcn->regs = regs;
128 dccg_dcn->dccg_shift = dccg_shift;
129 dccg_dcn->dccg_mask = dccg_mask;
130
131 return &dccg_dcn->base;
132}
133

source code of linux/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_dccg.c