1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Mediatek SPI NOR controller driver
4 //
5 // Copyright (C) 2020 Chuanhong Guo <gch981213@gmail.com>
6
7 #include <linux/bits.h>
8 #include <linux/clk.h>
9 #include <linux/completion.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/iopoll.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/spi/spi.h>
20 #include <linux/spi/spi-mem.h>
21 #include <linux/string.h>
22
23 #define DRIVER_NAME "mtk-spi-nor"
24
25 #define MTK_NOR_REG_CMD 0x00
26 #define MTK_NOR_CMD_WRITE BIT(4)
27 #define MTK_NOR_CMD_PROGRAM BIT(2)
28 #define MTK_NOR_CMD_READ BIT(0)
29 #define MTK_NOR_CMD_MASK GENMASK(5, 0)
30
31 #define MTK_NOR_REG_PRG_CNT 0x04
32 #define MTK_NOR_PRG_CNT_MAX 56
33 #define MTK_NOR_REG_RDATA 0x0c
34
35 #define MTK_NOR_REG_RADR0 0x10
36 #define MTK_NOR_REG_RADR(n) (MTK_NOR_REG_RADR0 + 4 * (n))
37 #define MTK_NOR_REG_RADR3 0xc8
38
39 #define MTK_NOR_REG_WDATA 0x1c
40
41 #define MTK_NOR_REG_PRGDATA0 0x20
42 #define MTK_NOR_REG_PRGDATA(n) (MTK_NOR_REG_PRGDATA0 + 4 * (n))
43 #define MTK_NOR_REG_PRGDATA_MAX 5
44
45 #define MTK_NOR_REG_SHIFT0 0x38
46 #define MTK_NOR_REG_SHIFT(n) (MTK_NOR_REG_SHIFT0 + 4 * (n))
47 #define MTK_NOR_REG_SHIFT_MAX 9
48
49 #define MTK_NOR_REG_CFG1 0x60
50 #define MTK_NOR_FAST_READ BIT(0)
51
52 #define MTK_NOR_REG_CFG2 0x64
53 #define MTK_NOR_WR_CUSTOM_OP_EN BIT(4)
54 #define MTK_NOR_WR_BUF_EN BIT(0)
55
56 #define MTK_NOR_REG_PP_DATA 0x98
57
58 #define MTK_NOR_REG_IRQ_STAT 0xa8
59 #define MTK_NOR_REG_IRQ_EN 0xac
60 #define MTK_NOR_IRQ_DMA BIT(7)
61 #define MTK_NOR_IRQ_MASK GENMASK(7, 0)
62
63 #define MTK_NOR_REG_CFG3 0xb4
64 #define MTK_NOR_DISABLE_WREN BIT(7)
65 #define MTK_NOR_DISABLE_SR_POLL BIT(5)
66
67 #define MTK_NOR_REG_WP 0xc4
68 #define MTK_NOR_ENABLE_SF_CMD 0x30
69
70 #define MTK_NOR_REG_BUSCFG 0xcc
71 #define MTK_NOR_4B_ADDR BIT(4)
72 #define MTK_NOR_QUAD_ADDR BIT(3)
73 #define MTK_NOR_QUAD_READ BIT(2)
74 #define MTK_NOR_DUAL_ADDR BIT(1)
75 #define MTK_NOR_DUAL_READ BIT(0)
76 #define MTK_NOR_BUS_MODE_MASK GENMASK(4, 0)
77
78 #define MTK_NOR_REG_DMA_CTL 0x718
79 #define MTK_NOR_DMA_START BIT(0)
80
81 #define MTK_NOR_REG_DMA_FADR 0x71c
82 #define MTK_NOR_REG_DMA_DADR 0x720
83 #define MTK_NOR_REG_DMA_END_DADR 0x724
84 #define MTK_NOR_REG_CG_DIS 0x728
85 #define MTK_NOR_SFC_SW_RST BIT(2)
86
87 #define MTK_NOR_REG_DMA_DADR_HB 0x738
88 #define MTK_NOR_REG_DMA_END_DADR_HB 0x73c
89
90 #define MTK_NOR_PRG_MAX_SIZE 6
91 // Reading DMA src/dst addresses have to be 16-byte aligned
92 #define MTK_NOR_DMA_ALIGN 16
93 #define MTK_NOR_DMA_ALIGN_MASK (MTK_NOR_DMA_ALIGN - 1)
94 // and we allocate a bounce buffer if destination address isn't aligned.
95 #define MTK_NOR_BOUNCE_BUF_SIZE PAGE_SIZE
96
97 // Buffered page program can do one 128-byte transfer
98 #define MTK_NOR_PP_SIZE 128
99
100 #define CLK_TO_US(sp, clkcnt) DIV_ROUND_UP(clkcnt, sp->spi_freq / 1000000)
101
102 struct mtk_nor_caps {
103 u8 dma_bits;
104
105 /* extra_dummy_bit is adding for the IP of new SoCs.
106 * Some new SoCs modify the timing of fetching registers' values
107 * and IDs of nor flash, they need a extra_dummy_bit which can add
108 * more clock cycles for fetching data.
109 */
110 u8 extra_dummy_bit;
111 };
112
113 struct mtk_nor {
114 struct spi_controller *ctlr;
115 struct device *dev;
116 void __iomem *base;
117 u8 *buffer;
118 dma_addr_t buffer_dma;
119 struct clk *spi_clk;
120 struct clk *ctlr_clk;
121 struct clk *axi_clk;
122 struct clk *axi_s_clk;
123 unsigned int spi_freq;
124 bool wbuf_en;
125 bool has_irq;
126 bool high_dma;
127 struct completion op_done;
128 const struct mtk_nor_caps *caps;
129 };
130
mtk_nor_rmw(struct mtk_nor * sp,u32 reg,u32 set,u32 clr)131 static inline void mtk_nor_rmw(struct mtk_nor *sp, u32 reg, u32 set, u32 clr)
132 {
133 u32 val = readl(sp->base + reg);
134
135 val &= ~clr;
136 val |= set;
137 writel(val, sp->base + reg);
138 }
139
mtk_nor_cmd_exec(struct mtk_nor * sp,u32 cmd,ulong clk)140 static inline int mtk_nor_cmd_exec(struct mtk_nor *sp, u32 cmd, ulong clk)
141 {
142 ulong delay = CLK_TO_US(sp, clk);
143 u32 reg;
144 int ret;
145
146 writel(cmd, sp->base + MTK_NOR_REG_CMD);
147 ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CMD, reg, !(reg & cmd),
148 delay / 3, (delay + 1) * 200);
149 if (ret < 0)
150 dev_err(sp->dev, "command %u timeout.\n", cmd);
151 return ret;
152 }
153
mtk_nor_reset(struct mtk_nor * sp)154 static void mtk_nor_reset(struct mtk_nor *sp)
155 {
156 mtk_nor_rmw(sp, MTK_NOR_REG_CG_DIS, 0, MTK_NOR_SFC_SW_RST);
157 mb(); /* flush previous writes */
158 mtk_nor_rmw(sp, MTK_NOR_REG_CG_DIS, MTK_NOR_SFC_SW_RST, 0);
159 mb(); /* flush previous writes */
160 writel(MTK_NOR_ENABLE_SF_CMD, sp->base + MTK_NOR_REG_WP);
161 }
162
mtk_nor_set_addr(struct mtk_nor * sp,const struct spi_mem_op * op)163 static void mtk_nor_set_addr(struct mtk_nor *sp, const struct spi_mem_op *op)
164 {
165 u32 addr = op->addr.val;
166 int i;
167
168 for (i = 0; i < 3; i++) {
169 writeb(addr & 0xff, sp->base + MTK_NOR_REG_RADR(i));
170 addr >>= 8;
171 }
172 if (op->addr.nbytes == 4) {
173 writeb(addr & 0xff, sp->base + MTK_NOR_REG_RADR3);
174 mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, MTK_NOR_4B_ADDR, 0);
175 } else {
176 mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, 0, MTK_NOR_4B_ADDR);
177 }
178 }
179
need_bounce(struct mtk_nor * sp,const struct spi_mem_op * op)180 static bool need_bounce(struct mtk_nor *sp, const struct spi_mem_op *op)
181 {
182 return ((uintptr_t)op->data.buf.in & MTK_NOR_DMA_ALIGN_MASK);
183 }
184
mtk_nor_match_read(const struct spi_mem_op * op)185 static bool mtk_nor_match_read(const struct spi_mem_op *op)
186 {
187 int dummy = 0;
188
189 if (op->dummy.nbytes)
190 dummy = op->dummy.nbytes * BITS_PER_BYTE / op->dummy.buswidth;
191
192 if ((op->data.buswidth == 2) || (op->data.buswidth == 4)) {
193 if (op->addr.buswidth == 1)
194 return dummy == 8;
195 else if (op->addr.buswidth == 2)
196 return dummy == 4;
197 else if (op->addr.buswidth == 4)
198 return dummy == 6;
199 } else if ((op->addr.buswidth == 1) && (op->data.buswidth == 1)) {
200 if (op->cmd.opcode == 0x03)
201 return dummy == 0;
202 else if (op->cmd.opcode == 0x0b)
203 return dummy == 8;
204 }
205 return false;
206 }
207
mtk_nor_match_prg(const struct spi_mem_op * op)208 static bool mtk_nor_match_prg(const struct spi_mem_op *op)
209 {
210 int tx_len, rx_len, prg_len, prg_left;
211
212 // prg mode is spi-only.
213 if ((op->cmd.buswidth > 1) || (op->addr.buswidth > 1) ||
214 (op->dummy.buswidth > 1) || (op->data.buswidth > 1))
215 return false;
216
217 tx_len = op->cmd.nbytes + op->addr.nbytes;
218
219 if (op->data.dir == SPI_MEM_DATA_OUT) {
220 // count dummy bytes only if we need to write data after it
221 tx_len += op->dummy.nbytes;
222
223 // leave at least one byte for data
224 if (tx_len > MTK_NOR_REG_PRGDATA_MAX)
225 return false;
226
227 // if there's no addr, meaning adjust_op_size is impossible,
228 // check data length as well.
229 if ((!op->addr.nbytes) &&
230 (tx_len + op->data.nbytes > MTK_NOR_REG_PRGDATA_MAX + 1))
231 return false;
232 } else if (op->data.dir == SPI_MEM_DATA_IN) {
233 if (tx_len > MTK_NOR_REG_PRGDATA_MAX + 1)
234 return false;
235
236 rx_len = op->data.nbytes;
237 prg_left = MTK_NOR_PRG_CNT_MAX / 8 - tx_len - op->dummy.nbytes;
238 if (prg_left > MTK_NOR_REG_SHIFT_MAX + 1)
239 prg_left = MTK_NOR_REG_SHIFT_MAX + 1;
240 if (rx_len > prg_left) {
241 if (!op->addr.nbytes)
242 return false;
243 rx_len = prg_left;
244 }
245
246 prg_len = tx_len + op->dummy.nbytes + rx_len;
247 if (prg_len > MTK_NOR_PRG_CNT_MAX / 8)
248 return false;
249 } else {
250 prg_len = tx_len + op->dummy.nbytes;
251 if (prg_len > MTK_NOR_PRG_CNT_MAX / 8)
252 return false;
253 }
254 return true;
255 }
256
mtk_nor_adj_prg_size(struct spi_mem_op * op)257 static void mtk_nor_adj_prg_size(struct spi_mem_op *op)
258 {
259 int tx_len, tx_left, prg_left;
260
261 tx_len = op->cmd.nbytes + op->addr.nbytes;
262 if (op->data.dir == SPI_MEM_DATA_OUT) {
263 tx_len += op->dummy.nbytes;
264 tx_left = MTK_NOR_REG_PRGDATA_MAX + 1 - tx_len;
265 if (op->data.nbytes > tx_left)
266 op->data.nbytes = tx_left;
267 } else if (op->data.dir == SPI_MEM_DATA_IN) {
268 prg_left = MTK_NOR_PRG_CNT_MAX / 8 - tx_len - op->dummy.nbytes;
269 if (prg_left > MTK_NOR_REG_SHIFT_MAX + 1)
270 prg_left = MTK_NOR_REG_SHIFT_MAX + 1;
271 if (op->data.nbytes > prg_left)
272 op->data.nbytes = prg_left;
273 }
274 }
275
mtk_nor_adjust_op_size(struct spi_mem * mem,struct spi_mem_op * op)276 static int mtk_nor_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
277 {
278 struct mtk_nor *sp = spi_controller_get_devdata(mem->spi->controller);
279
280 if (!op->data.nbytes)
281 return 0;
282
283 if ((op->addr.nbytes == 3) || (op->addr.nbytes == 4)) {
284 if ((op->data.dir == SPI_MEM_DATA_IN) &&
285 mtk_nor_match_read(op)) {
286 // limit size to prevent timeout calculation overflow
287 if (op->data.nbytes > 0x400000)
288 op->data.nbytes = 0x400000;
289
290 if ((op->addr.val & MTK_NOR_DMA_ALIGN_MASK) ||
291 (op->data.nbytes < MTK_NOR_DMA_ALIGN))
292 op->data.nbytes = 1;
293 else if (!need_bounce(sp, op))
294 op->data.nbytes &= ~MTK_NOR_DMA_ALIGN_MASK;
295 else if (op->data.nbytes > MTK_NOR_BOUNCE_BUF_SIZE)
296 op->data.nbytes = MTK_NOR_BOUNCE_BUF_SIZE;
297 return 0;
298 } else if (op->data.dir == SPI_MEM_DATA_OUT) {
299 if (op->data.nbytes >= MTK_NOR_PP_SIZE)
300 op->data.nbytes = MTK_NOR_PP_SIZE;
301 else
302 op->data.nbytes = 1;
303 return 0;
304 }
305 }
306
307 mtk_nor_adj_prg_size(op);
308 return 0;
309 }
310
mtk_nor_supports_op(struct spi_mem * mem,const struct spi_mem_op * op)311 static bool mtk_nor_supports_op(struct spi_mem *mem,
312 const struct spi_mem_op *op)
313 {
314 if (!spi_mem_default_supports_op(mem, op))
315 return false;
316
317 if (op->cmd.buswidth != 1)
318 return false;
319
320 if ((op->addr.nbytes == 3) || (op->addr.nbytes == 4)) {
321 switch (op->data.dir) {
322 case SPI_MEM_DATA_IN:
323 if (mtk_nor_match_read(op))
324 return true;
325 break;
326 case SPI_MEM_DATA_OUT:
327 if ((op->addr.buswidth == 1) &&
328 (op->dummy.nbytes == 0) &&
329 (op->data.buswidth == 1))
330 return true;
331 break;
332 default:
333 break;
334 }
335 }
336
337 return mtk_nor_match_prg(op);
338 }
339
mtk_nor_setup_bus(struct mtk_nor * sp,const struct spi_mem_op * op)340 static void mtk_nor_setup_bus(struct mtk_nor *sp, const struct spi_mem_op *op)
341 {
342 u32 reg = 0;
343
344 if (op->addr.nbytes == 4)
345 reg |= MTK_NOR_4B_ADDR;
346
347 if (op->data.buswidth == 4) {
348 reg |= MTK_NOR_QUAD_READ;
349 writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA(4));
350 if (op->addr.buswidth == 4)
351 reg |= MTK_NOR_QUAD_ADDR;
352 } else if (op->data.buswidth == 2) {
353 reg |= MTK_NOR_DUAL_READ;
354 writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA(3));
355 if (op->addr.buswidth == 2)
356 reg |= MTK_NOR_DUAL_ADDR;
357 } else {
358 if (op->cmd.opcode == 0x0b)
359 mtk_nor_rmw(sp, MTK_NOR_REG_CFG1, MTK_NOR_FAST_READ, 0);
360 else
361 mtk_nor_rmw(sp, MTK_NOR_REG_CFG1, 0, MTK_NOR_FAST_READ);
362 }
363 mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, reg, MTK_NOR_BUS_MODE_MASK);
364 }
365
mtk_nor_dma_exec(struct mtk_nor * sp,u32 from,unsigned int length,dma_addr_t dma_addr)366 static int mtk_nor_dma_exec(struct mtk_nor *sp, u32 from, unsigned int length,
367 dma_addr_t dma_addr)
368 {
369 int ret = 0;
370 u32 delay, timeout;
371 u32 reg;
372
373 writel(from, sp->base + MTK_NOR_REG_DMA_FADR);
374 writel(dma_addr, sp->base + MTK_NOR_REG_DMA_DADR);
375 writel(dma_addr + length, sp->base + MTK_NOR_REG_DMA_END_DADR);
376
377 if (sp->high_dma) {
378 writel(upper_32_bits(dma_addr),
379 sp->base + MTK_NOR_REG_DMA_DADR_HB);
380 writel(upper_32_bits(dma_addr + length),
381 sp->base + MTK_NOR_REG_DMA_END_DADR_HB);
382 }
383
384 if (sp->has_irq) {
385 reinit_completion(&sp->op_done);
386 mtk_nor_rmw(sp, MTK_NOR_REG_IRQ_EN, MTK_NOR_IRQ_DMA, 0);
387 }
388
389 mtk_nor_rmw(sp, MTK_NOR_REG_DMA_CTL, MTK_NOR_DMA_START, 0);
390
391 delay = CLK_TO_US(sp, (length + 5) * BITS_PER_BYTE);
392 timeout = (delay + 1) * 100;
393
394 if (sp->has_irq) {
395 if (!wait_for_completion_timeout(&sp->op_done,
396 usecs_to_jiffies(max(timeout, 10000U))))
397 ret = -ETIMEDOUT;
398 } else {
399 ret = readl_poll_timeout(sp->base + MTK_NOR_REG_DMA_CTL, reg,
400 !(reg & MTK_NOR_DMA_START), delay / 3,
401 timeout);
402 }
403
404 if (ret < 0)
405 dev_err(sp->dev, "dma read timeout.\n");
406
407 return ret;
408 }
409
mtk_nor_read_bounce(struct mtk_nor * sp,const struct spi_mem_op * op)410 static int mtk_nor_read_bounce(struct mtk_nor *sp, const struct spi_mem_op *op)
411 {
412 unsigned int rdlen;
413 int ret;
414
415 if (op->data.nbytes & MTK_NOR_DMA_ALIGN_MASK)
416 rdlen = (op->data.nbytes + MTK_NOR_DMA_ALIGN) & ~MTK_NOR_DMA_ALIGN_MASK;
417 else
418 rdlen = op->data.nbytes;
419
420 ret = mtk_nor_dma_exec(sp, op->addr.val, rdlen, sp->buffer_dma);
421
422 if (!ret)
423 memcpy(op->data.buf.in, sp->buffer, op->data.nbytes);
424
425 return ret;
426 }
427
mtk_nor_read_dma(struct mtk_nor * sp,const struct spi_mem_op * op)428 static int mtk_nor_read_dma(struct mtk_nor *sp, const struct spi_mem_op *op)
429 {
430 int ret;
431 dma_addr_t dma_addr;
432
433 if (need_bounce(sp, op))
434 return mtk_nor_read_bounce(sp, op);
435
436 dma_addr = dma_map_single(sp->dev, op->data.buf.in,
437 op->data.nbytes, DMA_FROM_DEVICE);
438
439 if (dma_mapping_error(sp->dev, dma_addr))
440 return -EINVAL;
441
442 ret = mtk_nor_dma_exec(sp, op->addr.val, op->data.nbytes, dma_addr);
443
444 dma_unmap_single(sp->dev, dma_addr, op->data.nbytes, DMA_FROM_DEVICE);
445
446 return ret;
447 }
448
mtk_nor_read_pio(struct mtk_nor * sp,const struct spi_mem_op * op)449 static int mtk_nor_read_pio(struct mtk_nor *sp, const struct spi_mem_op *op)
450 {
451 u8 *buf = op->data.buf.in;
452 int ret;
453
454 ret = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_READ, 6 * BITS_PER_BYTE);
455 if (!ret)
456 buf[0] = readb(sp->base + MTK_NOR_REG_RDATA);
457 return ret;
458 }
459
mtk_nor_setup_write_buffer(struct mtk_nor * sp,bool on)460 static int mtk_nor_setup_write_buffer(struct mtk_nor *sp, bool on)
461 {
462 int ret;
463 u32 val;
464
465 if (!(sp->wbuf_en ^ on))
466 return 0;
467
468 val = readl(sp->base + MTK_NOR_REG_CFG2);
469 if (on) {
470 writel(val | MTK_NOR_WR_BUF_EN, sp->base + MTK_NOR_REG_CFG2);
471 ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CFG2, val,
472 val & MTK_NOR_WR_BUF_EN, 0, 10000);
473 } else {
474 writel(val & ~MTK_NOR_WR_BUF_EN, sp->base + MTK_NOR_REG_CFG2);
475 ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CFG2, val,
476 !(val & MTK_NOR_WR_BUF_EN), 0, 10000);
477 }
478
479 if (!ret)
480 sp->wbuf_en = on;
481
482 return ret;
483 }
484
mtk_nor_pp_buffered(struct mtk_nor * sp,const struct spi_mem_op * op)485 static int mtk_nor_pp_buffered(struct mtk_nor *sp, const struct spi_mem_op *op)
486 {
487 const u8 *buf = op->data.buf.out;
488 u32 val;
489 int ret, i;
490
491 ret = mtk_nor_setup_write_buffer(sp, true);
492 if (ret < 0)
493 return ret;
494
495 for (i = 0; i < op->data.nbytes; i += 4) {
496 val = buf[i + 3] << 24 | buf[i + 2] << 16 | buf[i + 1] << 8 |
497 buf[i];
498 writel(val, sp->base + MTK_NOR_REG_PP_DATA);
499 }
500 return mtk_nor_cmd_exec(sp, MTK_NOR_CMD_WRITE,
501 (op->data.nbytes + 5) * BITS_PER_BYTE);
502 }
503
mtk_nor_pp_unbuffered(struct mtk_nor * sp,const struct spi_mem_op * op)504 static int mtk_nor_pp_unbuffered(struct mtk_nor *sp,
505 const struct spi_mem_op *op)
506 {
507 const u8 *buf = op->data.buf.out;
508 int ret;
509
510 ret = mtk_nor_setup_write_buffer(sp, false);
511 if (ret < 0)
512 return ret;
513 writeb(buf[0], sp->base + MTK_NOR_REG_WDATA);
514 return mtk_nor_cmd_exec(sp, MTK_NOR_CMD_WRITE, 6 * BITS_PER_BYTE);
515 }
516
mtk_nor_spi_mem_prg(struct mtk_nor * sp,const struct spi_mem_op * op)517 static int mtk_nor_spi_mem_prg(struct mtk_nor *sp, const struct spi_mem_op *op)
518 {
519 int rx_len = 0;
520 int reg_offset = MTK_NOR_REG_PRGDATA_MAX;
521 int tx_len, prg_len;
522 int i, ret;
523 void __iomem *reg;
524 u8 bufbyte;
525
526 tx_len = op->cmd.nbytes + op->addr.nbytes;
527
528 // count dummy bytes only if we need to write data after it
529 if (op->data.dir == SPI_MEM_DATA_OUT)
530 tx_len += op->dummy.nbytes + op->data.nbytes;
531 else if (op->data.dir == SPI_MEM_DATA_IN)
532 rx_len = op->data.nbytes;
533
534 prg_len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes +
535 op->data.nbytes;
536
537 // an invalid op may reach here if the caller calls exec_op without
538 // adjust_op_size. return -EINVAL instead of -ENOTSUPP so that
539 // spi-mem won't try this op again with generic spi transfers.
540 if ((tx_len > MTK_NOR_REG_PRGDATA_MAX + 1) ||
541 (rx_len > MTK_NOR_REG_SHIFT_MAX + 1) ||
542 (prg_len > MTK_NOR_PRG_CNT_MAX / 8))
543 return -EINVAL;
544
545 // fill tx data
546 for (i = op->cmd.nbytes; i > 0; i--, reg_offset--) {
547 reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
548 bufbyte = (op->cmd.opcode >> ((i - 1) * BITS_PER_BYTE)) & 0xff;
549 writeb(bufbyte, reg);
550 }
551
552 for (i = op->addr.nbytes; i > 0; i--, reg_offset--) {
553 reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
554 bufbyte = (op->addr.val >> ((i - 1) * BITS_PER_BYTE)) & 0xff;
555 writeb(bufbyte, reg);
556 }
557
558 if (op->data.dir == SPI_MEM_DATA_OUT) {
559 for (i = 0; i < op->dummy.nbytes; i++, reg_offset--) {
560 reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
561 writeb(0, reg);
562 }
563
564 for (i = 0; i < op->data.nbytes; i++, reg_offset--) {
565 reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
566 writeb(((const u8 *)(op->data.buf.out))[i], reg);
567 }
568 }
569
570 for (; reg_offset >= 0; reg_offset--) {
571 reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
572 writeb(0, reg);
573 }
574
575 // trigger op
576 if (rx_len)
577 writel(prg_len * BITS_PER_BYTE + sp->caps->extra_dummy_bit,
578 sp->base + MTK_NOR_REG_PRG_CNT);
579 else
580 writel(prg_len * BITS_PER_BYTE, sp->base + MTK_NOR_REG_PRG_CNT);
581
582 ret = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_PROGRAM,
583 prg_len * BITS_PER_BYTE);
584 if (ret)
585 return ret;
586
587 // fetch read data
588 reg_offset = 0;
589 if (op->data.dir == SPI_MEM_DATA_IN) {
590 for (i = op->data.nbytes - 1; i >= 0; i--, reg_offset++) {
591 reg = sp->base + MTK_NOR_REG_SHIFT(reg_offset);
592 ((u8 *)(op->data.buf.in))[i] = readb(reg);
593 }
594 }
595
596 return 0;
597 }
598
mtk_nor_exec_op(struct spi_mem * mem,const struct spi_mem_op * op)599 static int mtk_nor_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
600 {
601 struct mtk_nor *sp = spi_controller_get_devdata(mem->spi->controller);
602 int ret;
603
604 if ((op->data.nbytes == 0) ||
605 ((op->addr.nbytes != 3) && (op->addr.nbytes != 4)))
606 return mtk_nor_spi_mem_prg(sp, op);
607
608 if (op->data.dir == SPI_MEM_DATA_OUT) {
609 mtk_nor_set_addr(sp, op);
610 writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA0);
611 if (op->data.nbytes == MTK_NOR_PP_SIZE)
612 return mtk_nor_pp_buffered(sp, op);
613 return mtk_nor_pp_unbuffered(sp, op);
614 }
615
616 if ((op->data.dir == SPI_MEM_DATA_IN) && mtk_nor_match_read(op)) {
617 ret = mtk_nor_setup_write_buffer(sp, false);
618 if (ret < 0)
619 return ret;
620 mtk_nor_setup_bus(sp, op);
621 if (op->data.nbytes == 1) {
622 mtk_nor_set_addr(sp, op);
623 return mtk_nor_read_pio(sp, op);
624 } else {
625 ret = mtk_nor_read_dma(sp, op);
626 if (unlikely(ret)) {
627 /* Handle rare bus glitch */
628 mtk_nor_reset(sp);
629 mtk_nor_setup_bus(sp, op);
630 return mtk_nor_read_dma(sp, op);
631 }
632
633 return ret;
634 }
635 }
636
637 return mtk_nor_spi_mem_prg(sp, op);
638 }
639
mtk_nor_setup(struct spi_device * spi)640 static int mtk_nor_setup(struct spi_device *spi)
641 {
642 struct mtk_nor *sp = spi_controller_get_devdata(spi->controller);
643
644 if (spi->max_speed_hz && (spi->max_speed_hz < sp->spi_freq)) {
645 dev_err(&spi->dev, "spi clock should be %u Hz.\n",
646 sp->spi_freq);
647 return -EINVAL;
648 }
649 spi->max_speed_hz = sp->spi_freq;
650
651 return 0;
652 }
653
mtk_nor_transfer_one_message(struct spi_controller * host,struct spi_message * m)654 static int mtk_nor_transfer_one_message(struct spi_controller *host,
655 struct spi_message *m)
656 {
657 struct mtk_nor *sp = spi_controller_get_devdata(host);
658 struct spi_transfer *t = NULL;
659 unsigned long trx_len = 0;
660 int stat = 0;
661 int reg_offset = MTK_NOR_REG_PRGDATA_MAX;
662 void __iomem *reg;
663 const u8 *txbuf;
664 u8 *rxbuf;
665 int i;
666
667 list_for_each_entry(t, &m->transfers, transfer_list) {
668 txbuf = t->tx_buf;
669 for (i = 0; i < t->len; i++, reg_offset--) {
670 reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
671 if (txbuf)
672 writeb(txbuf[i], reg);
673 else
674 writeb(0, reg);
675 }
676 trx_len += t->len;
677 }
678
679 writel(trx_len * BITS_PER_BYTE, sp->base + MTK_NOR_REG_PRG_CNT);
680
681 stat = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_PROGRAM,
682 trx_len * BITS_PER_BYTE);
683 if (stat < 0)
684 goto msg_done;
685
686 reg_offset = trx_len - 1;
687 list_for_each_entry(t, &m->transfers, transfer_list) {
688 rxbuf = t->rx_buf;
689 for (i = 0; i < t->len; i++, reg_offset--) {
690 reg = sp->base + MTK_NOR_REG_SHIFT(reg_offset);
691 if (rxbuf)
692 rxbuf[i] = readb(reg);
693 }
694 }
695
696 m->actual_length = trx_len;
697 msg_done:
698 m->status = stat;
699 spi_finalize_current_message(host);
700
701 return 0;
702 }
703
mtk_nor_disable_clk(struct mtk_nor * sp)704 static void mtk_nor_disable_clk(struct mtk_nor *sp)
705 {
706 clk_disable_unprepare(sp->spi_clk);
707 clk_disable_unprepare(sp->ctlr_clk);
708 clk_disable_unprepare(sp->axi_clk);
709 clk_disable_unprepare(sp->axi_s_clk);
710 }
711
mtk_nor_enable_clk(struct mtk_nor * sp)712 static int mtk_nor_enable_clk(struct mtk_nor *sp)
713 {
714 int ret;
715
716 ret = clk_prepare_enable(sp->spi_clk);
717 if (ret)
718 return ret;
719
720 ret = clk_prepare_enable(sp->ctlr_clk);
721 if (ret) {
722 clk_disable_unprepare(sp->spi_clk);
723 return ret;
724 }
725
726 ret = clk_prepare_enable(sp->axi_clk);
727 if (ret) {
728 clk_disable_unprepare(sp->spi_clk);
729 clk_disable_unprepare(sp->ctlr_clk);
730 return ret;
731 }
732
733 ret = clk_prepare_enable(sp->axi_s_clk);
734 if (ret) {
735 clk_disable_unprepare(sp->spi_clk);
736 clk_disable_unprepare(sp->ctlr_clk);
737 clk_disable_unprepare(sp->axi_clk);
738 return ret;
739 }
740
741 return 0;
742 }
743
mtk_nor_init(struct mtk_nor * sp)744 static void mtk_nor_init(struct mtk_nor *sp)
745 {
746 writel(0, sp->base + MTK_NOR_REG_IRQ_EN);
747 writel(MTK_NOR_IRQ_MASK, sp->base + MTK_NOR_REG_IRQ_STAT);
748
749 writel(MTK_NOR_ENABLE_SF_CMD, sp->base + MTK_NOR_REG_WP);
750 mtk_nor_rmw(sp, MTK_NOR_REG_CFG2, MTK_NOR_WR_CUSTOM_OP_EN, 0);
751 mtk_nor_rmw(sp, MTK_NOR_REG_CFG3,
752 MTK_NOR_DISABLE_WREN | MTK_NOR_DISABLE_SR_POLL, 0);
753 }
754
mtk_nor_irq_handler(int irq,void * data)755 static irqreturn_t mtk_nor_irq_handler(int irq, void *data)
756 {
757 struct mtk_nor *sp = data;
758 u32 irq_status, irq_enabled;
759
760 irq_status = readl(sp->base + MTK_NOR_REG_IRQ_STAT);
761 irq_enabled = readl(sp->base + MTK_NOR_REG_IRQ_EN);
762 // write status back to clear interrupt
763 writel(irq_status, sp->base + MTK_NOR_REG_IRQ_STAT);
764
765 if (!(irq_status & irq_enabled))
766 return IRQ_NONE;
767
768 if (irq_status & MTK_NOR_IRQ_DMA) {
769 complete(&sp->op_done);
770 writel(0, sp->base + MTK_NOR_REG_IRQ_EN);
771 }
772
773 return IRQ_HANDLED;
774 }
775
mtk_max_msg_size(struct spi_device * spi)776 static size_t mtk_max_msg_size(struct spi_device *spi)
777 {
778 return MTK_NOR_PRG_MAX_SIZE;
779 }
780
781 static const struct spi_controller_mem_ops mtk_nor_mem_ops = {
782 .adjust_op_size = mtk_nor_adjust_op_size,
783 .supports_op = mtk_nor_supports_op,
784 .exec_op = mtk_nor_exec_op
785 };
786
787 static const struct mtk_nor_caps mtk_nor_caps_mt8173 = {
788 .dma_bits = 32,
789 .extra_dummy_bit = 0,
790 };
791
792 static const struct mtk_nor_caps mtk_nor_caps_mt8186 = {
793 .dma_bits = 32,
794 .extra_dummy_bit = 1,
795 };
796
797 static const struct mtk_nor_caps mtk_nor_caps_mt8192 = {
798 .dma_bits = 36,
799 .extra_dummy_bit = 0,
800 };
801
802 static const struct of_device_id mtk_nor_match[] = {
803 { .compatible = "mediatek,mt8173-nor", .data = &mtk_nor_caps_mt8173 },
804 { .compatible = "mediatek,mt8186-nor", .data = &mtk_nor_caps_mt8186 },
805 { .compatible = "mediatek,mt8192-nor", .data = &mtk_nor_caps_mt8192 },
806 { /* sentinel */ }
807 };
808 MODULE_DEVICE_TABLE(of, mtk_nor_match);
809
mtk_nor_probe(struct platform_device * pdev)810 static int mtk_nor_probe(struct platform_device *pdev)
811 {
812 struct spi_controller *ctlr;
813 struct mtk_nor *sp;
814 struct mtk_nor_caps *caps;
815 void __iomem *base;
816 struct clk *spi_clk, *ctlr_clk, *axi_clk, *axi_s_clk;
817 int ret, irq;
818
819 base = devm_platform_ioremap_resource(pdev, 0);
820 if (IS_ERR(base))
821 return PTR_ERR(base);
822
823 spi_clk = devm_clk_get(&pdev->dev, "spi");
824 if (IS_ERR(spi_clk))
825 return PTR_ERR(spi_clk);
826
827 ctlr_clk = devm_clk_get(&pdev->dev, "sf");
828 if (IS_ERR(ctlr_clk))
829 return PTR_ERR(ctlr_clk);
830
831 axi_clk = devm_clk_get_optional(&pdev->dev, "axi");
832 if (IS_ERR(axi_clk))
833 return PTR_ERR(axi_clk);
834
835 axi_s_clk = devm_clk_get_optional(&pdev->dev, "axi_s");
836 if (IS_ERR(axi_s_clk))
837 return PTR_ERR(axi_s_clk);
838
839 caps = (struct mtk_nor_caps *)of_device_get_match_data(&pdev->dev);
840
841 ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(caps->dma_bits));
842 if (ret) {
843 dev_err(&pdev->dev, "failed to set dma mask(%u)\n", caps->dma_bits);
844 return ret;
845 }
846
847 ctlr = devm_spi_alloc_host(&pdev->dev, sizeof(*sp));
848 if (!ctlr) {
849 dev_err(&pdev->dev, "failed to allocate spi controller\n");
850 return -ENOMEM;
851 }
852
853 ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
854 ctlr->dev.of_node = pdev->dev.of_node;
855 ctlr->max_message_size = mtk_max_msg_size;
856 ctlr->mem_ops = &mtk_nor_mem_ops;
857 ctlr->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD;
858 ctlr->num_chipselect = 1;
859 ctlr->setup = mtk_nor_setup;
860 ctlr->transfer_one_message = mtk_nor_transfer_one_message;
861 ctlr->auto_runtime_pm = true;
862
863 dev_set_drvdata(&pdev->dev, ctlr);
864
865 sp = spi_controller_get_devdata(ctlr);
866 sp->base = base;
867 sp->has_irq = false;
868 sp->wbuf_en = false;
869 sp->ctlr = ctlr;
870 sp->dev = &pdev->dev;
871 sp->spi_clk = spi_clk;
872 sp->ctlr_clk = ctlr_clk;
873 sp->axi_clk = axi_clk;
874 sp->axi_s_clk = axi_s_clk;
875 sp->caps = caps;
876 sp->high_dma = caps->dma_bits > 32;
877 sp->buffer = dmam_alloc_coherent(&pdev->dev,
878 MTK_NOR_BOUNCE_BUF_SIZE + MTK_NOR_DMA_ALIGN,
879 &sp->buffer_dma, GFP_KERNEL);
880 if (!sp->buffer)
881 return -ENOMEM;
882
883 if ((uintptr_t)sp->buffer & MTK_NOR_DMA_ALIGN_MASK) {
884 dev_err(sp->dev, "misaligned allocation of internal buffer.\n");
885 return -ENOMEM;
886 }
887
888 ret = mtk_nor_enable_clk(sp);
889 if (ret < 0)
890 return ret;
891
892 sp->spi_freq = clk_get_rate(sp->spi_clk);
893
894 mtk_nor_init(sp);
895
896 irq = platform_get_irq_optional(pdev, 0);
897
898 if (irq < 0) {
899 dev_warn(sp->dev, "IRQ not available.");
900 } else {
901 ret = devm_request_irq(sp->dev, irq, mtk_nor_irq_handler, 0,
902 pdev->name, sp);
903 if (ret < 0) {
904 dev_warn(sp->dev, "failed to request IRQ.");
905 } else {
906 init_completion(&sp->op_done);
907 sp->has_irq = true;
908 }
909 }
910
911 pm_runtime_set_autosuspend_delay(&pdev->dev, -1);
912 pm_runtime_use_autosuspend(&pdev->dev);
913 pm_runtime_set_active(&pdev->dev);
914 pm_runtime_enable(&pdev->dev);
915 pm_runtime_get_noresume(&pdev->dev);
916
917 ret = devm_spi_register_controller(&pdev->dev, ctlr);
918 if (ret < 0)
919 goto err_probe;
920
921 pm_runtime_mark_last_busy(&pdev->dev);
922 pm_runtime_put_autosuspend(&pdev->dev);
923
924 dev_info(&pdev->dev, "spi frequency: %d Hz\n", sp->spi_freq);
925
926 return 0;
927
928 err_probe:
929 pm_runtime_disable(&pdev->dev);
930 pm_runtime_set_suspended(&pdev->dev);
931 pm_runtime_dont_use_autosuspend(&pdev->dev);
932
933 mtk_nor_disable_clk(sp);
934
935 return ret;
936 }
937
mtk_nor_remove(struct platform_device * pdev)938 static void mtk_nor_remove(struct platform_device *pdev)
939 {
940 struct spi_controller *ctlr = dev_get_drvdata(&pdev->dev);
941 struct mtk_nor *sp = spi_controller_get_devdata(ctlr);
942
943 pm_runtime_disable(&pdev->dev);
944 pm_runtime_set_suspended(&pdev->dev);
945 pm_runtime_dont_use_autosuspend(&pdev->dev);
946
947 mtk_nor_disable_clk(sp);
948 }
949
mtk_nor_runtime_suspend(struct device * dev)950 static int __maybe_unused mtk_nor_runtime_suspend(struct device *dev)
951 {
952 struct spi_controller *ctlr = dev_get_drvdata(dev);
953 struct mtk_nor *sp = spi_controller_get_devdata(ctlr);
954
955 mtk_nor_disable_clk(sp);
956
957 return 0;
958 }
959
mtk_nor_runtime_resume(struct device * dev)960 static int __maybe_unused mtk_nor_runtime_resume(struct device *dev)
961 {
962 struct spi_controller *ctlr = dev_get_drvdata(dev);
963 struct mtk_nor *sp = spi_controller_get_devdata(ctlr);
964
965 return mtk_nor_enable_clk(sp);
966 }
967
mtk_nor_suspend(struct device * dev)968 static int __maybe_unused mtk_nor_suspend(struct device *dev)
969 {
970 return pm_runtime_force_suspend(dev);
971 }
972
mtk_nor_resume(struct device * dev)973 static int __maybe_unused mtk_nor_resume(struct device *dev)
974 {
975 struct spi_controller *ctlr = dev_get_drvdata(dev);
976 struct mtk_nor *sp = spi_controller_get_devdata(ctlr);
977 int ret;
978
979 ret = pm_runtime_force_resume(dev);
980 if (ret)
981 return ret;
982
983 mtk_nor_init(sp);
984
985 return 0;
986 }
987
988 static const struct dev_pm_ops mtk_nor_pm_ops = {
989 SET_RUNTIME_PM_OPS(mtk_nor_runtime_suspend,
990 mtk_nor_runtime_resume, NULL)
991 SET_SYSTEM_SLEEP_PM_OPS(mtk_nor_suspend, mtk_nor_resume)
992 };
993
994 static struct platform_driver mtk_nor_driver = {
995 .driver = {
996 .name = DRIVER_NAME,
997 .of_match_table = mtk_nor_match,
998 .pm = &mtk_nor_pm_ops,
999 },
1000 .probe = mtk_nor_probe,
1001 .remove_new = mtk_nor_remove,
1002 };
1003
1004 module_platform_driver(mtk_nor_driver);
1005
1006 MODULE_DESCRIPTION("Mediatek SPI NOR controller driver");
1007 MODULE_AUTHOR("Chuanhong Guo <gch981213@gmail.com>");
1008 MODULE_LICENSE("GPL v2");
1009 MODULE_ALIAS("platform:" DRIVER_NAME);
1010