1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2018 Cisco Systems, Inc.
4 *
5 * Author: Thomas Fitzsimmons <fitzsim@fitzsim.org>
6 */
7
8 #include <asm/io.h>
9 #include <command.h>
10 #include <config.h>
11 #include <dm.h>
12 #include <errno.h>
13 #include <fdtdec.h>
14 #include <linux/bitops.h>
15 #include <linux/delay.h>
16 #include <log.h>
17 #include <malloc.h>
18 #include <spi.h>
19 #include <time.h>
20
21 DECLARE_GLOBAL_DATA_PTR;
22
23 #define SPBR_MIN 8
24 #define BITS_PER_WORD 8
25
26 #define NUM_TXRAM 32
27 #define NUM_RXRAM 32
28 #define NUM_CDRAM 16
29
30 /* hif_mspi register structure. */
31 struct bcmstb_hif_mspi_regs {
32 u32 spcr0_lsb; /* 0x000 */
33 u32 spcr0_msb; /* 0x004 */
34 u32 spcr1_lsb; /* 0x008 */
35 u32 spcr1_msb; /* 0x00c */
36 u32 newqp; /* 0x010 */
37 u32 endqp; /* 0x014 */
38 u32 spcr2; /* 0x018 */
39 u32 reserved0; /* 0x01c */
40 u32 mspi_status; /* 0x020 */
41 u32 cptqp; /* 0x024 */
42 u32 spcr3; /* 0x028 */
43 u32 revision; /* 0x02c */
44 u32 reserved1[4]; /* 0x030 */
45 u32 txram[NUM_TXRAM]; /* 0x040 */
46 u32 rxram[NUM_RXRAM]; /* 0x0c0 */
47 u32 cdram[NUM_CDRAM]; /* 0x140 */
48 u32 write_lock; /* 0x180 */
49 };
50
51 /* hif_mspi masks. */
52 #define HIF_MSPI_SPCR2_CONT_AFTER_CMD_MASK 0x00000080
53 #define HIF_MSPI_SPCR2_SPE_MASK 0x00000040
54 #define HIF_MSPI_SPCR2_SPIFIE_MASK 0x00000020
55 #define HIF_MSPI_WRITE_LOCK_WRITE_LOCK_MASK 0x00000001
56
57 /* bspi offsets. */
58 #define BSPI_MAST_N_BOOT_CTRL 0x008
59
60 /* bspi_raf is not used in this driver. */
61
62 /* hif_spi_intr2 offsets and masks. */
63 #define HIF_SPI_INTR2_CPU_CLEAR 0x08
64 #define HIF_SPI_INTR2_CPU_MASK_SET 0x10
65 #define HIF_SPI_INTR2_CPU_MASK_CLEAR 0x14
66 #define HIF_SPI_INTR2_CPU_SET_MSPI_DONE_MASK 0x00000020
67
68 /* SPI transfer timeout in milliseconds. */
69 #define HIF_MSPI_WAIT 10
70
71 enum bcmstb_base_type {
72 HIF_MSPI,
73 BSPI,
74 HIF_SPI_INTR2,
75 CS_REG,
76 BASE_LAST,
77 };
78
79 struct bcmstb_spi_platdata {
80 void *base[4];
81 };
82
83 struct bcmstb_spi_priv {
84 struct bcmstb_hif_mspi_regs *regs;
85 void *bspi;
86 void *hif_spi_intr2;
87 void *cs_reg;
88 int default_cs;
89 int curr_cs;
90 uint tx_slot;
91 uint rx_slot;
92 u8 saved_cmd[NUM_CDRAM];
93 uint saved_cmd_len;
94 void *saved_din_addr;
95 };
96
bcmstb_spi_ofdata_to_platdata(struct udevice * bus)97 static int bcmstb_spi_ofdata_to_platdata(struct udevice *bus)
98 {
99 struct bcmstb_spi_platdata *plat = dev_get_platdata(bus);
100 const void *fdt = gd->fdt_blob;
101 int node = dev_of_offset(bus);
102 int ret = 0;
103 int i = 0;
104 struct fdt_resource resource = { 0 };
105 char *names[BASE_LAST] = { "hif_mspi", "bspi", "hif_spi_intr2",
106 "cs_reg" };
107 const phys_addr_t defaults[BASE_LAST] = { BCMSTB_HIF_MSPI_BASE,
108 BCMSTB_BSPI_BASE,
109 BCMSTB_HIF_SPI_INTR2,
110 BCMSTB_CS_REG };
111
112 for (i = 0; i < BASE_LAST; i++) {
113 plat->base[i] = (void *)defaults[i];
114
115 ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
116 names[i], &resource);
117 if (ret) {
118 printf("%s: Assuming BCMSTB SPI %s address 0x0x%p\n",
119 __func__, names[i], (void *)defaults[i]);
120 } else {
121 plat->base[i] = (void *)resource.start;
122 debug("BCMSTB SPI %s address: 0x0x%p\n",
123 names[i], (void *)plat->base[i]);
124 }
125 }
126
127 return 0;
128 }
129
bcmstb_spi_hw_set_parms(struct bcmstb_spi_priv * priv)130 static void bcmstb_spi_hw_set_parms(struct bcmstb_spi_priv *priv)
131 {
132 writel(SPBR_MIN, &priv->regs->spcr0_lsb);
133 writel(BITS_PER_WORD << 2 | SPI_MODE_3, &priv->regs->spcr0_msb);
134 }
135
bcmstb_spi_enable_interrupt(void * base,u32 mask)136 static void bcmstb_spi_enable_interrupt(void *base, u32 mask)
137 {
138 void *reg = base + HIF_SPI_INTR2_CPU_MASK_CLEAR;
139
140 writel(readl(reg) | mask, reg);
141 readl(reg);
142 }
143
bcmstb_spi_disable_interrupt(void * base,u32 mask)144 static void bcmstb_spi_disable_interrupt(void *base, u32 mask)
145 {
146 void *reg = base + HIF_SPI_INTR2_CPU_MASK_SET;
147
148 writel(readl(reg) | mask, reg);
149 readl(reg);
150 }
151
bcmstb_spi_clear_interrupt(void * base,u32 mask)152 static void bcmstb_spi_clear_interrupt(void *base, u32 mask)
153 {
154 void *reg = base + HIF_SPI_INTR2_CPU_CLEAR;
155
156 writel(readl(reg) | mask, reg);
157 readl(reg);
158 }
159
bcmstb_spi_probe(struct udevice * bus)160 static int bcmstb_spi_probe(struct udevice *bus)
161 {
162 struct bcmstb_spi_platdata *plat = dev_get_platdata(bus);
163 struct bcmstb_spi_priv *priv = dev_get_priv(bus);
164
165 priv->regs = plat->base[HIF_MSPI];
166 priv->bspi = plat->base[BSPI];
167 priv->hif_spi_intr2 = plat->base[HIF_SPI_INTR2];
168 priv->cs_reg = plat->base[CS_REG];
169 priv->default_cs = 0;
170 priv->curr_cs = -1;
171 priv->tx_slot = 0;
172 priv->rx_slot = 0;
173 memset(priv->saved_cmd, 0, NUM_CDRAM);
174 priv->saved_cmd_len = 0;
175 priv->saved_din_addr = NULL;
176
177 debug("spi_xfer: tx regs: 0x%p\n", &priv->regs->txram[0]);
178 debug("spi_xfer: rx regs: 0x%p\n", &priv->regs->rxram[0]);
179
180 /* Disable BSPI. */
181 writel(1, priv->bspi + BSPI_MAST_N_BOOT_CTRL);
182 readl(priv->bspi + BSPI_MAST_N_BOOT_CTRL);
183
184 /* Set up interrupts. */
185 bcmstb_spi_disable_interrupt(priv->hif_spi_intr2, 0xffffffff);
186 bcmstb_spi_clear_interrupt(priv->hif_spi_intr2, 0xffffffff);
187 bcmstb_spi_enable_interrupt(priv->hif_spi_intr2,
188 HIF_SPI_INTR2_CPU_SET_MSPI_DONE_MASK);
189
190 /* Set up control registers. */
191 writel(0, &priv->regs->spcr1_lsb);
192 writel(0, &priv->regs->spcr1_msb);
193 writel(0, &priv->regs->newqp);
194 writel(0, &priv->regs->endqp);
195 writel(HIF_MSPI_SPCR2_SPIFIE_MASK, &priv->regs->spcr2);
196 writel(0, &priv->regs->spcr3);
197
198 bcmstb_spi_hw_set_parms(priv);
199
200 return 0;
201 }
202
bcmstb_spi_submit(struct bcmstb_spi_priv * priv,bool done)203 static void bcmstb_spi_submit(struct bcmstb_spi_priv *priv, bool done)
204 {
205 debug("WR NEWQP: %d\n", 0);
206 writel(0, &priv->regs->newqp);
207
208 debug("WR ENDQP: %d\n", priv->tx_slot - 1);
209 writel(priv->tx_slot - 1, &priv->regs->endqp);
210
211 if (done) {
212 debug("WR CDRAM[%d]: %02x\n", priv->tx_slot - 1,
213 readl(&priv->regs->cdram[priv->tx_slot - 1]) & ~0x80);
214 writel(readl(&priv->regs->cdram[priv->tx_slot - 1]) & ~0x80,
215 &priv->regs->cdram[priv->tx_slot - 1]);
216 }
217
218 /* Force chip select first time. */
219 if (priv->curr_cs != priv->default_cs) {
220 debug("spi_xfer: switching chip select to %d\n",
221 priv->default_cs);
222 writel((readl(priv->cs_reg) & ~0xff) | (1 << priv->default_cs),
223 priv->cs_reg);
224 readl(priv->cs_reg);
225 udelay(10);
226 priv->curr_cs = priv->default_cs;
227 }
228
229 debug("WR WRITE_LOCK: %02x\n", 1);
230 writel((readl(&priv->regs->write_lock) &
231 ~HIF_MSPI_WRITE_LOCK_WRITE_LOCK_MASK) | 1,
232 &priv->regs->write_lock);
233 readl(&priv->regs->write_lock);
234
235 debug("WR SPCR2: %02x\n",
236 HIF_MSPI_SPCR2_SPIFIE_MASK |
237 HIF_MSPI_SPCR2_SPE_MASK |
238 HIF_MSPI_SPCR2_CONT_AFTER_CMD_MASK);
239 writel(HIF_MSPI_SPCR2_SPIFIE_MASK |
240 HIF_MSPI_SPCR2_SPE_MASK |
241 HIF_MSPI_SPCR2_CONT_AFTER_CMD_MASK,
242 &priv->regs->spcr2);
243 }
244
bcmstb_spi_wait(struct bcmstb_spi_priv * priv)245 static int bcmstb_spi_wait(struct bcmstb_spi_priv *priv)
246 {
247 u32 start_time = get_timer(0);
248 u32 status = readl(&priv->regs->mspi_status);
249
250 while (!(status & 1)) {
251 if (get_timer(start_time) > HIF_MSPI_WAIT)
252 return -ETIMEDOUT;
253 status = readl(&priv->regs->mspi_status);
254 }
255
256 writel(readl(&priv->regs->mspi_status) & ~1, &priv->regs->mspi_status);
257 bcmstb_spi_clear_interrupt(priv->hif_spi_intr2,
258 HIF_SPI_INTR2_CPU_SET_MSPI_DONE_MASK);
259
260 return 0;
261 }
262
bcmstb_spi_xfer(struct udevice * dev,unsigned int bitlen,const void * dout,void * din,unsigned long flags)263 static int bcmstb_spi_xfer(struct udevice *dev, unsigned int bitlen,
264 const void *dout, void *din, unsigned long flags)
265 {
266 uint len = bitlen / 8;
267 uint tx_len = len;
268 uint rx_len = len;
269 const u8 *out_bytes = (u8 *)dout;
270 u8 *in_bytes = (u8 *)din;
271 struct udevice *bus = dev_get_parent(dev);
272 struct bcmstb_spi_priv *priv = dev_get_priv(bus);
273 struct bcmstb_hif_mspi_regs *regs = priv->regs;
274
275 debug("spi_xfer: %d, t: 0x%p, r: 0x%p, f: %lx\n",
276 len, dout, din, flags);
277 debug("spi_xfer: chip select: %x\n", readl(priv->cs_reg) & 0xff);
278 debug("spi_xfer: tx addr: 0x%p\n", ®s->txram[0]);
279 debug("spi_xfer: rx addr: 0x%p\n", ®s->rxram[0]);
280 debug("spi_xfer: cd addr: 0x%p\n", ®s->cdram[0]);
281
282 if (flags & SPI_XFER_END) {
283 debug("spi_xfer: clearing saved din address: 0x%p\n",
284 priv->saved_din_addr);
285 priv->saved_din_addr = NULL;
286 priv->saved_cmd_len = 0;
287 memset(priv->saved_cmd, 0, NUM_CDRAM);
288 }
289
290 if (bitlen == 0)
291 return 0;
292
293 if (bitlen % 8) {
294 printf("%s: Non-byte-aligned transfer\n", __func__);
295 return -EOPNOTSUPP;
296 }
297
298 if (flags & ~(SPI_XFER_BEGIN | SPI_XFER_END)) {
299 printf("%s: Unsupported flags: %lx\n", __func__, flags);
300 return -EOPNOTSUPP;
301 }
302
303 if (flags & SPI_XFER_BEGIN) {
304 priv->tx_slot = 0;
305 priv->rx_slot = 0;
306
307 if (out_bytes && len > NUM_CDRAM) {
308 printf("%s: Unable to save transfer\n", __func__);
309 return -EOPNOTSUPP;
310 }
311
312 if (out_bytes && !(flags & SPI_XFER_END)) {
313 /*
314 * This is the start of a transmit operation
315 * that will need repeating if the calling
316 * code polls for the result. Save it for
317 * subsequent transmission.
318 */
319 debug("spi_xfer: saving command: %x, %d\n",
320 out_bytes[0], len);
321 priv->saved_cmd_len = len;
322 memcpy(priv->saved_cmd, out_bytes, priv->saved_cmd_len);
323 }
324 }
325
326 if (!(flags & (SPI_XFER_BEGIN | SPI_XFER_END))) {
327 if (priv->saved_din_addr == din) {
328 /*
329 * The caller is polling for status. Repeat
330 * the last transmission.
331 */
332 int ret = 0;
333
334 debug("spi_xfer: Making recursive call\n");
335 ret = bcmstb_spi_xfer(dev, priv->saved_cmd_len * 8,
336 priv->saved_cmd, NULL,
337 SPI_XFER_BEGIN);
338 if (ret) {
339 printf("%s: Recursive call failed\n", __func__);
340 return ret;
341 }
342 } else {
343 debug("spi_xfer: saving din address: 0x%p\n", din);
344 priv->saved_din_addr = din;
345 }
346 }
347
348 while (rx_len > 0) {
349 priv->rx_slot = priv->tx_slot;
350
351 while (priv->tx_slot < NUM_CDRAM && tx_len > 0) {
352 bcmstb_spi_hw_set_parms(priv);
353 debug("WR TXRAM[%d]: %02x\n", priv->tx_slot,
354 out_bytes ? out_bytes[len - tx_len] : 0xff);
355 writel(out_bytes ? out_bytes[len - tx_len] : 0xff,
356 ®s->txram[priv->tx_slot << 1]);
357 debug("WR CDRAM[%d]: %02x\n", priv->tx_slot, 0x8e);
358 writel(0x8e, ®s->cdram[priv->tx_slot]);
359 priv->tx_slot++;
360 tx_len--;
361 if (!in_bytes)
362 rx_len--;
363 }
364
365 debug("spi_xfer: early return clauses: %d, %d, %d\n",
366 len <= NUM_CDRAM,
367 !in_bytes,
368 (flags & (SPI_XFER_BEGIN |
369 SPI_XFER_END)) == SPI_XFER_BEGIN);
370 if (len <= NUM_CDRAM &&
371 !in_bytes &&
372 (flags & (SPI_XFER_BEGIN | SPI_XFER_END)) == SPI_XFER_BEGIN)
373 return 0;
374
375 bcmstb_spi_submit(priv, tx_len == 0);
376
377 if (bcmstb_spi_wait(priv) == -ETIMEDOUT) {
378 printf("%s: Timed out\n", __func__);
379 return -ETIMEDOUT;
380 }
381
382 priv->tx_slot %= NUM_CDRAM;
383
384 if (in_bytes) {
385 while (priv->rx_slot < NUM_CDRAM && rx_len > 0) {
386 in_bytes[len - rx_len] =
387 readl(®s->rxram[(priv->rx_slot << 1)
388 + 1])
389 & 0xff;
390 debug("RD RXRAM[%d]: %02x\n",
391 priv->rx_slot, in_bytes[len - rx_len]);
392 priv->rx_slot++;
393 rx_len--;
394 }
395 }
396 }
397
398 if (flags & SPI_XFER_END) {
399 debug("WR WRITE_LOCK: %02x\n", 0);
400 writel((readl(&priv->regs->write_lock) &
401 ~HIF_MSPI_WRITE_LOCK_WRITE_LOCK_MASK) | 0,
402 &priv->regs->write_lock);
403 readl(&priv->regs->write_lock);
404 }
405
406 return 0;
407 }
408
bcmstb_spi_set_speed(struct udevice * dev,uint speed)409 static int bcmstb_spi_set_speed(struct udevice *dev, uint speed)
410 {
411 return 0;
412 }
413
bcmstb_spi_set_mode(struct udevice * dev,uint mode)414 static int bcmstb_spi_set_mode(struct udevice *dev, uint mode)
415 {
416 return 0;
417 }
418
419 static const struct dm_spi_ops bcmstb_spi_ops = {
420 .xfer = bcmstb_spi_xfer,
421 .set_speed = bcmstb_spi_set_speed,
422 .set_mode = bcmstb_spi_set_mode,
423 };
424
425 static const struct udevice_id bcmstb_spi_id[] = {
426 { .compatible = "brcm,spi-brcmstb" },
427 { }
428 };
429
430 U_BOOT_DRIVER(bcmstb_spi) = {
431 .name = "bcmstb_spi",
432 .id = UCLASS_SPI,
433 .of_match = bcmstb_spi_id,
434 .ops = &bcmstb_spi_ops,
435 .ofdata_to_platdata = bcmstb_spi_ofdata_to_platdata,
436 .probe = bcmstb_spi_probe,
437 .platdata_auto_alloc_size = sizeof(struct bcmstb_spi_platdata),
438 .priv_auto_alloc_size = sizeof(struct bcmstb_spi_priv),
439 };
440