1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) 2 // Copyright(c) 2015-2020 Intel Corporation. 3 4 /* 5 * Bandwidth management algorithm based on 2^n gears 6 * 7 */ 8 9 #include <linux/bitops.h> 10 #include <linux/device.h> 11 #include <linux/module.h> 12 #include <linux/mod_devicetable.h> 13 #include <linux/slab.h> 14 #include <linux/soundwire/sdw.h> 15 #include "bus.h" 16 17 #define SDW_STRM_RATE_GROUPING 1 18 19 struct sdw_group_params { 20 unsigned int rate; 21 int full_bw; 22 int payload_bw; 23 int hwidth; 24 }; 25 26 struct sdw_group { 27 unsigned int count; 28 unsigned int max_size; 29 unsigned int *rates; 30 }; 31 32 void sdw_compute_slave_ports(struct sdw_master_runtime *m_rt, 33 struct sdw_transport_data *t_data) 34 { 35 struct sdw_slave_runtime *s_rt = NULL; 36 struct sdw_port_runtime *p_rt; 37 int port_bo, sample_int; 38 unsigned int rate, bps, ch = 0; 39 unsigned int slave_total_ch; 40 struct sdw_bus_params *b_params = &m_rt->bus->params; 41 42 port_bo = t_data->block_offset; 43 44 list_for_each_entry(s_rt, &m_rt->slave_rt_list, m_rt_node) { 45 rate = m_rt->stream->params.rate; 46 bps = m_rt->stream->params.bps; 47 sample_int = (m_rt->bus->params.curr_dr_freq / rate); 48 slave_total_ch = 0; 49 50 list_for_each_entry(p_rt, &s_rt->port_list, port_node) { 51 ch = hweight32(p_rt->ch_mask); 52 53 sdw_fill_xport_params(&p_rt->transport_params, 54 p_rt->num, false, 55 SDW_BLK_GRP_CNT_1, 56 sample_int, port_bo, port_bo >> 8, 57 t_data->hstart, 58 t_data->hstop, 59 SDW_BLK_PKG_PER_PORT, 0x0); 60 61 sdw_fill_port_params(&p_rt->port_params, 62 p_rt->num, bps, 63 SDW_PORT_FLOW_MODE_ISOCH, 64 b_params->s_data_mode); 65 66 port_bo += bps * ch; 67 slave_total_ch += ch; 68 } 69 70 if (m_rt->direction == SDW_DATA_DIR_TX && 71 m_rt->ch_count == slave_total_ch) { 72 /* 73 * Slave devices were configured to access all channels 74 * of the stream, which indicates that they operate in 75 * 'mirror mode'. Make sure we reset the port offset for 76 * the next device in the list 77 */ 78 port_bo = t_data->block_offset; 79 } 80 } 81 } 82 EXPORT_SYMBOL(sdw_compute_slave_ports); 83 84 static void sdw_compute_master_ports(struct sdw_master_runtime *m_rt, 85 struct sdw_group_params *params, 86 int port_bo, int hstop) 87 { 88 struct sdw_transport_data t_data = {0}; 89 struct sdw_port_runtime *p_rt; 90 struct sdw_bus *bus = m_rt->bus; 91 struct sdw_bus_params *b_params = &bus->params; 92 int sample_int, hstart = 0; 93 unsigned int rate, bps, ch; 94 95 rate = m_rt->stream->params.rate; 96 bps = m_rt->stream->params.bps; 97 ch = m_rt->ch_count; 98 sample_int = (bus->params.curr_dr_freq / rate); 99 100 if (rate != params->rate) 101 return; 102 103 t_data.hstop = hstop; 104 hstart = hstop - params->hwidth + 1; 105 t_data.hstart = hstart; 106 107 list_for_each_entry(p_rt, &m_rt->port_list, port_node) { 108 109 sdw_fill_xport_params(&p_rt->transport_params, p_rt->num, 110 false, SDW_BLK_GRP_CNT_1, sample_int, 111 port_bo, port_bo >> 8, hstart, hstop, 112 SDW_BLK_PKG_PER_PORT, 0x0); 113 114 sdw_fill_port_params(&p_rt->port_params, 115 p_rt->num, bps, 116 SDW_PORT_FLOW_MODE_ISOCH, 117 b_params->m_data_mode); 118 119 /* Check for first entry */ 120 if (!(p_rt == list_first_entry(&m_rt->port_list, 121 struct sdw_port_runtime, 122 port_node))) { 123 port_bo += bps * ch; 124 continue; 125 } 126 127 t_data.hstart = hstart; 128 t_data.hstop = hstop; 129 t_data.block_offset = port_bo; 130 t_data.sub_block_offset = 0; 131 port_bo += bps * ch; 132 } 133 134 sdw_compute_slave_ports(m_rt, &t_data); 135 } 136 137 static void _sdw_compute_port_params(struct sdw_bus *bus, 138 struct sdw_group_params *params, int count) 139 { 140 struct sdw_master_runtime *m_rt; 141 int hstop = bus->params.col - 1; 142 int port_bo, i; 143 144 /* Run loop for all groups to compute transport parameters */ 145 for (i = 0; i < count; i++) { 146 port_bo = 1; 147 148 list_for_each_entry(m_rt, &bus->m_rt_list, bus_node) { 149 sdw_compute_master_ports(m_rt, ¶ms[i], port_bo, hstop); 150 151 port_bo += m_rt->ch_count * m_rt->stream->params.bps; 152 } 153 154 hstop = hstop - params[i].hwidth; 155 } 156 } 157 158 static int sdw_compute_group_params(struct sdw_bus *bus, 159 struct sdw_group_params *params, 160 int *rates, int count) 161 { 162 struct sdw_master_runtime *m_rt; 163 int sel_col = bus->params.col; 164 unsigned int rate, bps, ch; 165 int i, column_needed = 0; 166 167 /* Calculate bandwidth per group */ 168 for (i = 0; i < count; i++) { 169 params[i].rate = rates[i]; 170 params[i].full_bw = bus->params.curr_dr_freq / params[i].rate; 171 } 172 173 list_for_each_entry(m_rt, &bus->m_rt_list, bus_node) { 174 rate = m_rt->stream->params.rate; 175 bps = m_rt->stream->params.bps; 176 ch = m_rt->ch_count; 177 178 for (i = 0; i < count; i++) { 179 if (rate == params[i].rate) 180 params[i].payload_bw += bps * ch; 181 } 182 } 183 184 for (i = 0; i < count; i++) { 185 params[i].hwidth = (sel_col * 186 params[i].payload_bw + params[i].full_bw - 1) / 187 params[i].full_bw; 188 189 column_needed += params[i].hwidth; 190 } 191 192 if (column_needed > sel_col - 1) 193 return -EINVAL; 194 195 return 0; 196 } 197 198 static int sdw_add_element_group_count(struct sdw_group *group, 199 unsigned int rate) 200 { 201 int num = group->count; 202 int i; 203 204 for (i = 0; i <= num; i++) { 205 if (rate == group->rates[i]) 206 break; 207 208 if (i != num) 209 continue; 210 211 if (group->count >= group->max_size) { 212 unsigned int *rates; 213 214 group->max_size += 1; 215 rates = krealloc(group->rates, 216 (sizeof(int) * group->max_size), 217 GFP_KERNEL); 218 if (!rates) 219 return -ENOMEM; 220 group->rates = rates; 221 } 222 223 group->rates[group->count++] = rate; 224 } 225 226 return 0; 227 } 228 229 static int sdw_get_group_count(struct sdw_bus *bus, 230 struct sdw_group *group) 231 { 232 struct sdw_master_runtime *m_rt; 233 unsigned int rate; 234 int ret = 0; 235 236 group->count = 0; 237 group->max_size = SDW_STRM_RATE_GROUPING; 238 group->rates = kcalloc(group->max_size, sizeof(int), GFP_KERNEL); 239 if (!group->rates) 240 return -ENOMEM; 241 242 list_for_each_entry(m_rt, &bus->m_rt_list, bus_node) { 243 rate = m_rt->stream->params.rate; 244 if (m_rt == list_first_entry(&bus->m_rt_list, 245 struct sdw_master_runtime, 246 bus_node)) { 247 group->rates[group->count++] = rate; 248 249 } else { 250 ret = sdw_add_element_group_count(group, rate); 251 if (ret < 0) { 252 kfree(group->rates); 253 return ret; 254 } 255 } 256 } 257 258 return ret; 259 } 260 261 /** 262 * sdw_compute_port_params: Compute transport and port parameters 263 * 264 * @bus: SDW Bus instance 265 */ 266 static int sdw_compute_port_params(struct sdw_bus *bus) 267 { 268 struct sdw_group_params *params = NULL; 269 struct sdw_group group; 270 int ret; 271 272 ret = sdw_get_group_count(bus, &group); 273 if (ret < 0) 274 return ret; 275 276 if (group.count == 0) 277 goto out; 278 279 params = kcalloc(group.count, sizeof(*params), GFP_KERNEL); 280 if (!params) { 281 ret = -ENOMEM; 282 goto out; 283 } 284 285 /* Compute transport parameters for grouped streams */ 286 ret = sdw_compute_group_params(bus, params, 287 &group.rates[0], group.count); 288 if (ret < 0) 289 goto free_params; 290 291 _sdw_compute_port_params(bus, params, group.count); 292 293 free_params: 294 kfree(params); 295 out: 296 kfree(group.rates); 297 298 return ret; 299 } 300 301 static int sdw_select_row_col(struct sdw_bus *bus, int clk_freq) 302 { 303 struct sdw_master_prop *prop = &bus->prop; 304 int frame_int, frame_freq; 305 int r, c; 306 307 for (c = 0; c < SDW_FRAME_COLS; c++) { 308 for (r = 0; r < SDW_FRAME_ROWS; r++) { 309 if (sdw_rows[r] != prop->default_row || 310 sdw_cols[c] != prop->default_col) 311 continue; 312 313 frame_int = sdw_rows[r] * sdw_cols[c]; 314 frame_freq = clk_freq / frame_int; 315 316 if ((clk_freq - (frame_freq * SDW_FRAME_CTRL_BITS)) < 317 bus->params.bandwidth) 318 continue; 319 320 bus->params.row = sdw_rows[r]; 321 bus->params.col = sdw_cols[c]; 322 return 0; 323 } 324 } 325 326 return -EINVAL; 327 } 328 329 /** 330 * sdw_compute_bus_params: Compute bus parameters 331 * 332 * @bus: SDW Bus instance 333 */ 334 static int sdw_compute_bus_params(struct sdw_bus *bus) 335 { 336 unsigned int max_dr_freq, curr_dr_freq = 0; 337 struct sdw_master_prop *mstr_prop = &bus->prop; 338 int i, clk_values, ret; 339 bool is_gear = false; 340 u32 *clk_buf; 341 342 if (mstr_prop->num_clk_gears) { 343 clk_values = mstr_prop->num_clk_gears; 344 clk_buf = mstr_prop->clk_gears; 345 is_gear = true; 346 } else if (mstr_prop->num_clk_freq) { 347 clk_values = mstr_prop->num_clk_freq; 348 clk_buf = mstr_prop->clk_freq; 349 } else { 350 clk_values = 1; 351 clk_buf = NULL; 352 } 353 354 max_dr_freq = mstr_prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR; 355 356 for (i = 0; i < clk_values; i++) { 357 if (!clk_buf) 358 curr_dr_freq = max_dr_freq; 359 else 360 curr_dr_freq = (is_gear) ? 361 (max_dr_freq >> clk_buf[i]) : 362 clk_buf[i] * SDW_DOUBLE_RATE_FACTOR; 363 364 if (curr_dr_freq <= bus->params.bandwidth) 365 continue; 366 367 break; 368 369 /* 370 * TODO: Check all the Slave(s) port(s) audio modes and find 371 * whether given clock rate is supported with glitchless 372 * transition. 373 */ 374 } 375 376 if (i == clk_values) { 377 dev_err(bus->dev, "%s: could not find clock value for bandwidth %d\n", 378 __func__, bus->params.bandwidth); 379 return -EINVAL; 380 } 381 382 ret = sdw_select_row_col(bus, curr_dr_freq); 383 if (ret < 0) { 384 dev_err(bus->dev, "%s: could not find frame configuration for bus dr_freq %d\n", 385 __func__, curr_dr_freq); 386 return -EINVAL; 387 } 388 389 bus->params.curr_dr_freq = curr_dr_freq; 390 return 0; 391 } 392 393 /** 394 * sdw_compute_params: Compute bus, transport and port parameters 395 * 396 * @bus: SDW Bus instance 397 */ 398 int sdw_compute_params(struct sdw_bus *bus) 399 { 400 int ret; 401 402 /* Computes clock frequency, frame shape and frame frequency */ 403 ret = sdw_compute_bus_params(bus); 404 if (ret < 0) 405 return ret; 406 407 /* Compute transport and port params */ 408 ret = sdw_compute_port_params(bus); 409 if (ret < 0) { 410 dev_err(bus->dev, "Compute transport params failed: %d\n", ret); 411 return ret; 412 } 413 414 return 0; 415 } 416 EXPORT_SYMBOL(sdw_compute_params); 417 418 MODULE_LICENSE("Dual BSD/GPL"); 419 MODULE_DESCRIPTION("SoundWire Generic Bandwidth Allocation"); 420