1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2012 4 * Altera Corporation <www.altera.com> 5 */ 6 7 #include <common.h> 8 #include <dm.h> 9 #include <fdtdec.h> 10 #include <malloc.h> 11 #include <spi.h> 12 #include <linux/errno.h> 13 #include "cadence_qspi.h" 14 15 #define CQSPI_STIG_READ 0 16 #define CQSPI_STIG_WRITE 1 17 #define CQSPI_INDIRECT_READ 2 18 #define CQSPI_INDIRECT_WRITE 3 19 20 DECLARE_GLOBAL_DATA_PTR; 21 22 static int cadence_spi_write_speed(struct udevice *bus, uint hz) 23 { 24 struct cadence_spi_platdata *plat = bus->platdata; 25 struct cadence_spi_priv *priv = dev_get_priv(bus); 26 27 cadence_qspi_apb_config_baudrate_div(priv->regbase, 28 CONFIG_CQSPI_REF_CLK, hz); 29 30 /* Reconfigure delay timing if speed is changed. */ 31 cadence_qspi_apb_delay(priv->regbase, CONFIG_CQSPI_REF_CLK, hz, 32 plat->tshsl_ns, plat->tsd2d_ns, 33 plat->tchsh_ns, plat->tslch_ns); 34 35 return 0; 36 } 37 38 /* Calibration sequence to determine the read data capture delay register */ 39 static int spi_calibration(struct udevice *bus, uint hz) 40 { 41 struct cadence_spi_priv *priv = dev_get_priv(bus); 42 void *base = priv->regbase; 43 u8 opcode_rdid = 0x9F; 44 unsigned int idcode = 0, temp = 0; 45 int err = 0, i, range_lo = -1, range_hi = -1; 46 47 /* start with slowest clock (1 MHz) */ 48 cadence_spi_write_speed(bus, 1000000); 49 50 /* configure the read data capture delay register to 0 */ 51 cadence_qspi_apb_readdata_capture(base, 1, 0); 52 53 /* Enable QSPI */ 54 cadence_qspi_apb_controller_enable(base); 55 56 /* read the ID which will be our golden value */ 57 err = cadence_qspi_apb_command_read(base, 1, &opcode_rdid, 58 3, (u8 *)&idcode); 59 if (err) { 60 puts("SF: Calibration failed (read)\n"); 61 return err; 62 } 63 64 /* use back the intended clock and find low range */ 65 cadence_spi_write_speed(bus, hz); 66 for (i = 0; i < CQSPI_READ_CAPTURE_MAX_DELAY; i++) { 67 /* Disable QSPI */ 68 cadence_qspi_apb_controller_disable(base); 69 70 /* reconfigure the read data capture delay register */ 71 cadence_qspi_apb_readdata_capture(base, 1, i); 72 73 /* Enable back QSPI */ 74 cadence_qspi_apb_controller_enable(base); 75 76 /* issue a RDID to get the ID value */ 77 err = cadence_qspi_apb_command_read(base, 1, &opcode_rdid, 78 3, (u8 *)&temp); 79 if (err) { 80 puts("SF: Calibration failed (read)\n"); 81 return err; 82 } 83 84 /* search for range lo */ 85 if (range_lo == -1 && temp == idcode) { 86 range_lo = i; 87 continue; 88 } 89 90 /* search for range hi */ 91 if (range_lo != -1 && temp != idcode) { 92 range_hi = i - 1; 93 break; 94 } 95 range_hi = i; 96 } 97 98 if (range_lo == -1) { 99 puts("SF: Calibration failed (low range)\n"); 100 return err; 101 } 102 103 /* Disable QSPI for subsequent initialization */ 104 cadence_qspi_apb_controller_disable(base); 105 106 /* configure the final value for read data capture delay register */ 107 cadence_qspi_apb_readdata_capture(base, 1, (range_hi + range_lo) / 2); 108 debug("SF: Read data capture delay calibrated to %i (%i - %i)\n", 109 (range_hi + range_lo) / 2, range_lo, range_hi); 110 111 /* just to ensure we do once only when speed or chip select change */ 112 priv->qspi_calibrated_hz = hz; 113 priv->qspi_calibrated_cs = spi_chip_select(bus); 114 115 return 0; 116 } 117 118 static int cadence_spi_set_speed(struct udevice *bus, uint hz) 119 { 120 struct cadence_spi_platdata *plat = bus->platdata; 121 struct cadence_spi_priv *priv = dev_get_priv(bus); 122 int err; 123 124 if (hz > plat->max_hz) 125 hz = plat->max_hz; 126 127 /* Disable QSPI */ 128 cadence_qspi_apb_controller_disable(priv->regbase); 129 130 /* 131 * Calibration required for different current SCLK speed, requested 132 * SCLK speed or chip select 133 */ 134 if (priv->previous_hz != hz || 135 priv->qspi_calibrated_hz != hz || 136 priv->qspi_calibrated_cs != spi_chip_select(bus)) { 137 err = spi_calibration(bus, hz); 138 if (err) 139 return err; 140 141 /* prevent calibration run when same as previous request */ 142 priv->previous_hz = hz; 143 } 144 145 /* Enable QSPI */ 146 cadence_qspi_apb_controller_enable(priv->regbase); 147 148 debug("%s: speed=%d\n", __func__, hz); 149 150 return 0; 151 } 152 153 static int cadence_spi_probe(struct udevice *bus) 154 { 155 struct cadence_spi_platdata *plat = bus->platdata; 156 struct cadence_spi_priv *priv = dev_get_priv(bus); 157 158 priv->regbase = plat->regbase; 159 priv->ahbbase = plat->ahbbase; 160 161 if (!priv->qspi_is_init) { 162 cadence_qspi_apb_controller_init(plat); 163 priv->qspi_is_init = 1; 164 } 165 166 return 0; 167 } 168 169 static int cadence_spi_set_mode(struct udevice *bus, uint mode) 170 { 171 struct cadence_spi_priv *priv = dev_get_priv(bus); 172 173 /* Disable QSPI */ 174 cadence_qspi_apb_controller_disable(priv->regbase); 175 176 /* Set SPI mode */ 177 cadence_qspi_apb_set_clk_mode(priv->regbase, mode); 178 179 /* Enable QSPI */ 180 cadence_qspi_apb_controller_enable(priv->regbase); 181 182 return 0; 183 } 184 185 static int cadence_spi_xfer(struct udevice *dev, unsigned int bitlen, 186 const void *dout, void *din, unsigned long flags) 187 { 188 struct udevice *bus = dev->parent; 189 struct cadence_spi_platdata *plat = bus->platdata; 190 struct cadence_spi_priv *priv = dev_get_priv(bus); 191 struct dm_spi_slave_platdata *dm_plat = dev_get_parent_platdata(dev); 192 void *base = priv->regbase; 193 u8 *cmd_buf = priv->cmd_buf; 194 size_t data_bytes; 195 int err = 0; 196 u32 mode = CQSPI_STIG_WRITE; 197 198 if (flags & SPI_XFER_BEGIN) { 199 /* copy command to local buffer */ 200 priv->cmd_len = bitlen / 8; 201 memcpy(cmd_buf, dout, priv->cmd_len); 202 } 203 204 if (flags == (SPI_XFER_BEGIN | SPI_XFER_END)) { 205 /* if start and end bit are set, the data bytes is 0. */ 206 data_bytes = 0; 207 } else { 208 data_bytes = bitlen / 8; 209 } 210 debug("%s: len=%zu [bytes]\n", __func__, data_bytes); 211 212 /* Set Chip select */ 213 cadence_qspi_apb_chipselect(base, spi_chip_select(dev), 214 plat->is_decoded_cs); 215 216 if ((flags & SPI_XFER_END) || (flags == 0)) { 217 if (priv->cmd_len == 0) { 218 printf("QSPI: Error, command is empty.\n"); 219 return -1; 220 } 221 222 if (din && data_bytes) { 223 /* read */ 224 /* Use STIG if no address. */ 225 if (!CQSPI_IS_ADDR(priv->cmd_len)) 226 mode = CQSPI_STIG_READ; 227 else 228 mode = CQSPI_INDIRECT_READ; 229 } else if (dout && !(flags & SPI_XFER_BEGIN)) { 230 /* write */ 231 if (!CQSPI_IS_ADDR(priv->cmd_len)) 232 mode = CQSPI_STIG_WRITE; 233 else 234 mode = CQSPI_INDIRECT_WRITE; 235 } 236 237 switch (mode) { 238 case CQSPI_STIG_READ: 239 err = cadence_qspi_apb_command_read( 240 base, priv->cmd_len, cmd_buf, 241 data_bytes, din); 242 243 break; 244 case CQSPI_STIG_WRITE: 245 err = cadence_qspi_apb_command_write(base, 246 priv->cmd_len, cmd_buf, 247 data_bytes, dout); 248 break; 249 case CQSPI_INDIRECT_READ: 250 err = cadence_qspi_apb_indirect_read_setup(plat, 251 priv->cmd_len, dm_plat->mode, cmd_buf); 252 if (!err) { 253 err = cadence_qspi_apb_indirect_read_execute 254 (plat, data_bytes, din); 255 } 256 break; 257 case CQSPI_INDIRECT_WRITE: 258 err = cadence_qspi_apb_indirect_write_setup 259 (plat, priv->cmd_len, cmd_buf); 260 if (!err) { 261 err = cadence_qspi_apb_indirect_write_execute 262 (plat, data_bytes, dout); 263 } 264 break; 265 default: 266 err = -1; 267 break; 268 } 269 270 if (flags & SPI_XFER_END) { 271 /* clear command buffer */ 272 memset(cmd_buf, 0, sizeof(priv->cmd_buf)); 273 priv->cmd_len = 0; 274 } 275 } 276 277 return err; 278 } 279 280 static int cadence_spi_ofdata_to_platdata(struct udevice *bus) 281 { 282 struct cadence_spi_platdata *plat = bus->platdata; 283 const void *blob = gd->fdt_blob; 284 int node = dev_of_offset(bus); 285 int subnode; 286 287 plat->regbase = (void *)devfdt_get_addr_index(bus, 0); 288 plat->ahbbase = (void *)devfdt_get_addr_index(bus, 1); 289 plat->is_decoded_cs = fdtdec_get_bool(blob, node, "cdns,is-decoded-cs"); 290 plat->fifo_depth = fdtdec_get_uint(blob, node, "cdns,fifo-depth", 128); 291 plat->fifo_width = fdtdec_get_uint(blob, node, "cdns,fifo-width", 4); 292 plat->trigger_address = fdtdec_get_uint(blob, node, 293 "cdns,trigger-address", 0); 294 295 /* All other paramters are embedded in the child node */ 296 subnode = fdt_first_subnode(blob, node); 297 if (subnode < 0) { 298 printf("Error: subnode with SPI flash config missing!\n"); 299 return -ENODEV; 300 } 301 302 /* Use 500 KHz as a suitable default */ 303 plat->max_hz = fdtdec_get_uint(blob, subnode, "spi-max-frequency", 304 500000); 305 306 /* Read other parameters from DT */ 307 plat->page_size = fdtdec_get_uint(blob, subnode, "page-size", 256); 308 plat->block_size = fdtdec_get_uint(blob, subnode, "block-size", 16); 309 plat->tshsl_ns = fdtdec_get_uint(blob, subnode, "cdns,tshsl-ns", 200); 310 plat->tsd2d_ns = fdtdec_get_uint(blob, subnode, "cdns,tsd2d-ns", 255); 311 plat->tchsh_ns = fdtdec_get_uint(blob, subnode, "cdns,tchsh-ns", 20); 312 plat->tslch_ns = fdtdec_get_uint(blob, subnode, "cdns,tslch-ns", 20); 313 314 debug("%s: regbase=%p ahbbase=%p max-frequency=%d page-size=%d\n", 315 __func__, plat->regbase, plat->ahbbase, plat->max_hz, 316 plat->page_size); 317 318 return 0; 319 } 320 321 static const struct dm_spi_ops cadence_spi_ops = { 322 .xfer = cadence_spi_xfer, 323 .set_speed = cadence_spi_set_speed, 324 .set_mode = cadence_spi_set_mode, 325 /* 326 * cs_info is not needed, since we require all chip selects to be 327 * in the device tree explicitly 328 */ 329 }; 330 331 static const struct udevice_id cadence_spi_ids[] = { 332 { .compatible = "cdns,qspi-nor" }, 333 { } 334 }; 335 336 U_BOOT_DRIVER(cadence_spi) = { 337 .name = "cadence_spi", 338 .id = UCLASS_SPI, 339 .of_match = cadence_spi_ids, 340 .ops = &cadence_spi_ops, 341 .ofdata_to_platdata = cadence_spi_ofdata_to_platdata, 342 .platdata_auto_alloc_size = sizeof(struct cadence_spi_platdata), 343 .priv_auto_alloc_size = sizeof(struct cadence_spi_priv), 344 .probe = cadence_spi_probe, 345 }; 346