treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / mtd / lpddr / lpddr2_nvm.c
blob0f1547f09d08b43f4aa483d2003d4d473ed78ad6
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * LPDDR2-NVM MTD driver. This module provides read, write, erase, lock/unlock
4 * support for LPDDR2-NVM PCM memories
6 * Copyright © 2012 Micron Technology, Inc.
8 * Vincenzo Aliberti <vincenzo.aliberti@gmail.com>
9 * Domenico Manna <domenico.manna@gmail.com>
10 * Many thanks to Andrea Vigilante for initial enabling
13 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
15 #include <linux/init.h>
16 #include <linux/io.h>
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/mtd/map.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/partitions.h>
22 #include <linux/slab.h>
23 #include <linux/platform_device.h>
24 #include <linux/ioport.h>
25 #include <linux/err.h>
27 /* Parameters */
28 #define ERASE_BLOCKSIZE (0x00020000/2) /* in Word */
29 #define WRITE_BUFFSIZE (0x00000400/2) /* in Word */
30 #define OW_BASE_ADDRESS 0x00000000 /* OW offset */
31 #define BUS_WIDTH 0x00000020 /* x32 devices */
33 /* PFOW symbols address offset */
34 #define PFOW_QUERY_STRING_P (0x0000/2) /* in Word */
35 #define PFOW_QUERY_STRING_F (0x0002/2) /* in Word */
36 #define PFOW_QUERY_STRING_O (0x0004/2) /* in Word */
37 #define PFOW_QUERY_STRING_W (0x0006/2) /* in Word */
39 /* OW registers address */
40 #define CMD_CODE_OFS (0x0080/2) /* in Word */
41 #define CMD_DATA_OFS (0x0084/2) /* in Word */
42 #define CMD_ADD_L_OFS (0x0088/2) /* in Word */
43 #define CMD_ADD_H_OFS (0x008A/2) /* in Word */
44 #define MPR_L_OFS (0x0090/2) /* in Word */
45 #define MPR_H_OFS (0x0092/2) /* in Word */
46 #define CMD_EXEC_OFS (0x00C0/2) /* in Word */
47 #define STATUS_REG_OFS (0x00CC/2) /* in Word */
48 #define PRG_BUFFER_OFS (0x0010/2) /* in Word */
50 /* Datamask */
51 #define MR_CFGMASK 0x8000
52 #define SR_OK_DATAMASK 0x0080
54 /* LPDDR2-NVM Commands */
55 #define LPDDR2_NVM_LOCK 0x0061
56 #define LPDDR2_NVM_UNLOCK 0x0062
57 #define LPDDR2_NVM_SW_PROGRAM 0x0041
58 #define LPDDR2_NVM_SW_OVERWRITE 0x0042
59 #define LPDDR2_NVM_BUF_PROGRAM 0x00E9
60 #define LPDDR2_NVM_BUF_OVERWRITE 0x00EA
61 #define LPDDR2_NVM_ERASE 0x0020
63 /* LPDDR2-NVM Registers offset */
64 #define LPDDR2_MODE_REG_DATA 0x0040
65 #define LPDDR2_MODE_REG_CFG 0x0050
68 * Internal Type Definitions
69 * pcm_int_data contains memory controller details:
70 * @reg_data : LPDDR2_MODE_REG_DATA register address after remapping
71 * @reg_cfg : LPDDR2_MODE_REG_CFG register address after remapping
72 * &bus_width: memory bus-width (eg: x16 2 Bytes, x32 4 Bytes)
74 struct pcm_int_data {
75 void __iomem *ctl_regs;
76 int bus_width;
79 static DEFINE_MUTEX(lpdd2_nvm_mutex);
82 * Build a map_word starting from an u_long
84 static inline map_word build_map_word(u_long myword)
86 map_word val = { {0} };
87 val.x[0] = myword;
88 return val;
92 * Build Mode Register Configuration DataMask based on device bus-width
94 static inline u_int build_mr_cfgmask(u_int bus_width)
96 u_int val = MR_CFGMASK;
98 if (bus_width == 0x0004) /* x32 device */
99 val = val << 16;
101 return val;
105 * Build Status Register OK DataMask based on device bus-width
107 static inline u_int build_sr_ok_datamask(u_int bus_width)
109 u_int val = SR_OK_DATAMASK;
111 if (bus_width == 0x0004) /* x32 device */
112 val = (val << 16)+val;
114 return val;
118 * Evaluates Overlay Window Control Registers address
120 static inline u_long ow_reg_add(struct map_info *map, u_long offset)
122 u_long val = 0;
123 struct pcm_int_data *pcm_data = map->fldrv_priv;
125 val = map->pfow_base + offset*pcm_data->bus_width;
127 return val;
131 * Enable lpddr2-nvm Overlay Window
132 * Overlay Window is a memory mapped area containing all LPDDR2-NVM registers
133 * used by device commands as well as uservisible resources like Device Status
134 * Register, Device ID, etc
136 static inline void ow_enable(struct map_info *map)
138 struct pcm_int_data *pcm_data = map->fldrv_priv;
140 writel_relaxed(build_mr_cfgmask(pcm_data->bus_width) | 0x18,
141 pcm_data->ctl_regs + LPDDR2_MODE_REG_CFG);
142 writel_relaxed(0x01, pcm_data->ctl_regs + LPDDR2_MODE_REG_DATA);
146 * Disable lpddr2-nvm Overlay Window
147 * Overlay Window is a memory mapped area containing all LPDDR2-NVM registers
148 * used by device commands as well as uservisible resources like Device Status
149 * Register, Device ID, etc
151 static inline void ow_disable(struct map_info *map)
153 struct pcm_int_data *pcm_data = map->fldrv_priv;
155 writel_relaxed(build_mr_cfgmask(pcm_data->bus_width) | 0x18,
156 pcm_data->ctl_regs + LPDDR2_MODE_REG_CFG);
157 writel_relaxed(0x02, pcm_data->ctl_regs + LPDDR2_MODE_REG_DATA);
161 * Execute lpddr2-nvm operations
163 static int lpddr2_nvm_do_op(struct map_info *map, u_long cmd_code,
164 u_long cmd_data, u_long cmd_add, u_long cmd_mpr, u_char *buf)
166 map_word add_l = { {0} }, add_h = { {0} }, mpr_l = { {0} },
167 mpr_h = { {0} }, data_l = { {0} }, cmd = { {0} },
168 exec_cmd = { {0} }, sr;
169 map_word data_h = { {0} }; /* only for 2x x16 devices stacked */
170 u_long i, status_reg, prg_buff_ofs;
171 struct pcm_int_data *pcm_data = map->fldrv_priv;
172 u_int sr_ok_datamask = build_sr_ok_datamask(pcm_data->bus_width);
174 /* Builds low and high words for OW Control Registers */
175 add_l.x[0] = cmd_add & 0x0000FFFF;
176 add_h.x[0] = (cmd_add >> 16) & 0x0000FFFF;
177 mpr_l.x[0] = cmd_mpr & 0x0000FFFF;
178 mpr_h.x[0] = (cmd_mpr >> 16) & 0x0000FFFF;
179 cmd.x[0] = cmd_code & 0x0000FFFF;
180 exec_cmd.x[0] = 0x0001;
181 data_l.x[0] = cmd_data & 0x0000FFFF;
182 data_h.x[0] = (cmd_data >> 16) & 0x0000FFFF; /* only for 2x x16 */
184 /* Set Overlay Window Control Registers */
185 map_write(map, cmd, ow_reg_add(map, CMD_CODE_OFS));
186 map_write(map, data_l, ow_reg_add(map, CMD_DATA_OFS));
187 map_write(map, add_l, ow_reg_add(map, CMD_ADD_L_OFS));
188 map_write(map, add_h, ow_reg_add(map, CMD_ADD_H_OFS));
189 map_write(map, mpr_l, ow_reg_add(map, MPR_L_OFS));
190 map_write(map, mpr_h, ow_reg_add(map, MPR_H_OFS));
191 if (pcm_data->bus_width == 0x0004) { /* 2x16 devices stacked */
192 map_write(map, cmd, ow_reg_add(map, CMD_CODE_OFS) + 2);
193 map_write(map, data_h, ow_reg_add(map, CMD_DATA_OFS) + 2);
194 map_write(map, add_l, ow_reg_add(map, CMD_ADD_L_OFS) + 2);
195 map_write(map, add_h, ow_reg_add(map, CMD_ADD_H_OFS) + 2);
196 map_write(map, mpr_l, ow_reg_add(map, MPR_L_OFS) + 2);
197 map_write(map, mpr_h, ow_reg_add(map, MPR_H_OFS) + 2);
200 /* Fill Program Buffer */
201 if ((cmd_code == LPDDR2_NVM_BUF_PROGRAM) ||
202 (cmd_code == LPDDR2_NVM_BUF_OVERWRITE)) {
203 prg_buff_ofs = (map_read(map,
204 ow_reg_add(map, PRG_BUFFER_OFS))).x[0];
205 for (i = 0; i < cmd_mpr; i++) {
206 map_write(map, build_map_word(buf[i]), map->pfow_base +
207 prg_buff_ofs + i);
211 /* Command Execute */
212 map_write(map, exec_cmd, ow_reg_add(map, CMD_EXEC_OFS));
213 if (pcm_data->bus_width == 0x0004) /* 2x16 devices stacked */
214 map_write(map, exec_cmd, ow_reg_add(map, CMD_EXEC_OFS) + 2);
216 /* Status Register Check */
217 do {
218 sr = map_read(map, ow_reg_add(map, STATUS_REG_OFS));
219 status_reg = sr.x[0];
220 if (pcm_data->bus_width == 0x0004) {/* 2x16 devices stacked */
221 sr = map_read(map, ow_reg_add(map,
222 STATUS_REG_OFS) + 2);
223 status_reg += sr.x[0] << 16;
225 } while ((status_reg & sr_ok_datamask) != sr_ok_datamask);
227 return (((status_reg & sr_ok_datamask) == sr_ok_datamask) ? 0 : -EIO);
231 * Execute lpddr2-nvm operations @ block level
233 static int lpddr2_nvm_do_block_op(struct mtd_info *mtd, loff_t start_add,
234 uint64_t len, u_char block_op)
236 struct map_info *map = mtd->priv;
237 u_long add, end_add;
238 int ret = 0;
240 mutex_lock(&lpdd2_nvm_mutex);
242 ow_enable(map);
244 add = start_add;
245 end_add = add + len;
247 do {
248 ret = lpddr2_nvm_do_op(map, block_op, 0x00, add, add, NULL);
249 if (ret)
250 goto out;
251 add += mtd->erasesize;
252 } while (add < end_add);
254 out:
255 ow_disable(map);
256 mutex_unlock(&lpdd2_nvm_mutex);
257 return ret;
261 * verify presence of PFOW string
263 static int lpddr2_nvm_pfow_present(struct map_info *map)
265 map_word pfow_val[4];
266 unsigned int found = 1;
268 mutex_lock(&lpdd2_nvm_mutex);
270 ow_enable(map);
272 /* Load string from array */
273 pfow_val[0] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_P));
274 pfow_val[1] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_F));
275 pfow_val[2] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_O));
276 pfow_val[3] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_W));
278 /* Verify the string loaded vs expected */
279 if (!map_word_equal(map, build_map_word('P'), pfow_val[0]))
280 found = 0;
281 if (!map_word_equal(map, build_map_word('F'), pfow_val[1]))
282 found = 0;
283 if (!map_word_equal(map, build_map_word('O'), pfow_val[2]))
284 found = 0;
285 if (!map_word_equal(map, build_map_word('W'), pfow_val[3]))
286 found = 0;
288 ow_disable(map);
290 mutex_unlock(&lpdd2_nvm_mutex);
292 return found;
296 * lpddr2_nvm driver read method
298 static int lpddr2_nvm_read(struct mtd_info *mtd, loff_t start_add,
299 size_t len, size_t *retlen, u_char *buf)
301 struct map_info *map = mtd->priv;
303 mutex_lock(&lpdd2_nvm_mutex);
305 *retlen = len;
307 map_copy_from(map, buf, start_add, *retlen);
309 mutex_unlock(&lpdd2_nvm_mutex);
310 return 0;
314 * lpddr2_nvm driver write method
316 static int lpddr2_nvm_write(struct mtd_info *mtd, loff_t start_add,
317 size_t len, size_t *retlen, const u_char *buf)
319 struct map_info *map = mtd->priv;
320 struct pcm_int_data *pcm_data = map->fldrv_priv;
321 u_long add, current_len, tot_len, target_len, my_data;
322 u_char *write_buf = (u_char *)buf;
323 int ret = 0;
325 mutex_lock(&lpdd2_nvm_mutex);
327 ow_enable(map);
329 /* Set start value for the variables */
330 add = start_add;
331 target_len = len;
332 tot_len = 0;
334 while (tot_len < target_len) {
335 if (!(IS_ALIGNED(add, mtd->writesize))) { /* do sw program */
336 my_data = write_buf[tot_len];
337 my_data += (write_buf[tot_len+1]) << 8;
338 if (pcm_data->bus_width == 0x0004) {/* 2x16 devices */
339 my_data += (write_buf[tot_len+2]) << 16;
340 my_data += (write_buf[tot_len+3]) << 24;
342 ret = lpddr2_nvm_do_op(map, LPDDR2_NVM_SW_OVERWRITE,
343 my_data, add, 0x00, NULL);
344 if (ret)
345 goto out;
347 add += pcm_data->bus_width;
348 tot_len += pcm_data->bus_width;
349 } else { /* do buffer program */
350 current_len = min(target_len - tot_len,
351 (u_long) mtd->writesize);
352 ret = lpddr2_nvm_do_op(map, LPDDR2_NVM_BUF_OVERWRITE,
353 0x00, add, current_len, write_buf + tot_len);
354 if (ret)
355 goto out;
357 add += current_len;
358 tot_len += current_len;
362 out:
363 *retlen = tot_len;
364 ow_disable(map);
365 mutex_unlock(&lpdd2_nvm_mutex);
366 return ret;
370 * lpddr2_nvm driver erase method
372 static int lpddr2_nvm_erase(struct mtd_info *mtd, struct erase_info *instr)
374 return lpddr2_nvm_do_block_op(mtd, instr->addr, instr->len,
375 LPDDR2_NVM_ERASE);
379 * lpddr2_nvm driver unlock method
381 static int lpddr2_nvm_unlock(struct mtd_info *mtd, loff_t start_add,
382 uint64_t len)
384 return lpddr2_nvm_do_block_op(mtd, start_add, len, LPDDR2_NVM_UNLOCK);
388 * lpddr2_nvm driver lock method
390 static int lpddr2_nvm_lock(struct mtd_info *mtd, loff_t start_add,
391 uint64_t len)
393 return lpddr2_nvm_do_block_op(mtd, start_add, len, LPDDR2_NVM_LOCK);
397 * lpddr2_nvm driver probe method
399 static int lpddr2_nvm_probe(struct platform_device *pdev)
401 struct map_info *map;
402 struct mtd_info *mtd;
403 struct resource *add_range;
404 struct resource *control_regs;
405 struct pcm_int_data *pcm_data;
407 /* Allocate memory control_regs data structures */
408 pcm_data = devm_kzalloc(&pdev->dev, sizeof(*pcm_data), GFP_KERNEL);
409 if (!pcm_data)
410 return -ENOMEM;
412 pcm_data->bus_width = BUS_WIDTH;
414 /* Allocate memory for map_info & mtd_info data structures */
415 map = devm_kzalloc(&pdev->dev, sizeof(*map), GFP_KERNEL);
416 if (!map)
417 return -ENOMEM;
419 mtd = devm_kzalloc(&pdev->dev, sizeof(*mtd), GFP_KERNEL);
420 if (!mtd)
421 return -ENOMEM;
423 /* lpddr2_nvm address range */
424 add_range = platform_get_resource(pdev, IORESOURCE_MEM, 0);
426 /* Populate map_info data structure */
427 *map = (struct map_info) {
428 .virt = devm_ioremap_resource(&pdev->dev, add_range),
429 .name = pdev->dev.init_name,
430 .phys = add_range->start,
431 .size = resource_size(add_range),
432 .bankwidth = pcm_data->bus_width / 2,
433 .pfow_base = OW_BASE_ADDRESS,
434 .fldrv_priv = pcm_data,
436 if (IS_ERR(map->virt))
437 return PTR_ERR(map->virt);
439 simple_map_init(map); /* fill with default methods */
441 control_regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
442 pcm_data->ctl_regs = devm_ioremap_resource(&pdev->dev, control_regs);
443 if (IS_ERR(pcm_data->ctl_regs))
444 return PTR_ERR(pcm_data->ctl_regs);
446 /* Populate mtd_info data structure */
447 *mtd = (struct mtd_info) {
448 .dev = { .parent = &pdev->dev },
449 .name = pdev->dev.init_name,
450 .type = MTD_RAM,
451 .priv = map,
452 .size = resource_size(add_range),
453 .erasesize = ERASE_BLOCKSIZE * pcm_data->bus_width,
454 .writesize = 1,
455 .writebufsize = WRITE_BUFFSIZE * pcm_data->bus_width,
456 .flags = (MTD_CAP_NVRAM | MTD_POWERUP_LOCK),
457 ._read = lpddr2_nvm_read,
458 ._write = lpddr2_nvm_write,
459 ._erase = lpddr2_nvm_erase,
460 ._unlock = lpddr2_nvm_unlock,
461 ._lock = lpddr2_nvm_lock,
464 /* Verify the presence of the device looking for PFOW string */
465 if (!lpddr2_nvm_pfow_present(map)) {
466 pr_err("device not recognized\n");
467 return -EINVAL;
469 /* Parse partitions and register the MTD device */
470 return mtd_device_register(mtd, NULL, 0);
474 * lpddr2_nvm driver remove method
476 static int lpddr2_nvm_remove(struct platform_device *pdev)
478 return mtd_device_unregister(dev_get_drvdata(&pdev->dev));
481 /* Initialize platform_driver data structure for lpddr2_nvm */
482 static struct platform_driver lpddr2_nvm_drv = {
483 .driver = {
484 .name = "lpddr2_nvm",
486 .probe = lpddr2_nvm_probe,
487 .remove = lpddr2_nvm_remove,
490 module_platform_driver(lpddr2_nvm_drv);
491 MODULE_LICENSE("GPL");
492 MODULE_AUTHOR("Vincenzo Aliberti <vincenzo.aliberti@gmail.com>");
493 MODULE_DESCRIPTION("MTD driver for LPDDR2-NVM PCM memories");