1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * HiSilicon FMC SPI NOR flash controller driver
4 *
5 * Copyright (c) 2015-2016 HiSilicon Technologies Co., Ltd.
6 */
7#include <linux/bitops.h>
8#include <linux/clk.h>
9#include <linux/dma-mapping.h>
10#include <linux/iopoll.h>
11#include <linux/module.h>
12#include <linux/mtd/mtd.h>
13#include <linux/mtd/spi-nor.h>
14#include <linux/of.h>
15#include <linux/platform_device.h>
16#include <linux/slab.h>
17
18/* Hardware register offsets and field definitions */
19#define FMC_CFG				0x00
20#define FMC_CFG_OP_MODE_MASK		BIT_MASK(0)
21#define FMC_CFG_OP_MODE_BOOT		0
22#define FMC_CFG_OP_MODE_NORMAL		1
23#define FMC_CFG_FLASH_SEL(type)		(((type) & 0x3) << 1)
24#define FMC_CFG_FLASH_SEL_MASK		0x6
25#define FMC_ECC_TYPE(type)		(((type) & 0x7) << 5)
26#define FMC_ECC_TYPE_MASK		GENMASK(7, 5)
27#define SPI_NOR_ADDR_MODE_MASK		BIT_MASK(10)
28#define SPI_NOR_ADDR_MODE_3BYTES	(0x0 << 10)
29#define SPI_NOR_ADDR_MODE_4BYTES	(0x1 << 10)
30#define FMC_GLOBAL_CFG			0x04
31#define FMC_GLOBAL_CFG_WP_ENABLE	BIT(6)
32#define FMC_SPI_TIMING_CFG		0x08
33#define TIMING_CFG_TCSH(nr)		(((nr) & 0xf) << 8)
34#define TIMING_CFG_TCSS(nr)		(((nr) & 0xf) << 4)
35#define TIMING_CFG_TSHSL(nr)		((nr) & 0xf)
36#define CS_HOLD_TIME			0x6
37#define CS_SETUP_TIME			0x6
38#define CS_DESELECT_TIME		0xf
39#define FMC_INT				0x18
40#define FMC_INT_OP_DONE			BIT(0)
41#define FMC_INT_CLR			0x20
42#define FMC_CMD				0x24
43#define FMC_CMD_CMD1(cmd)		((cmd) & 0xff)
44#define FMC_ADDRL			0x2c
45#define FMC_OP_CFG			0x30
46#define OP_CFG_FM_CS(cs)		((cs) << 11)
47#define OP_CFG_MEM_IF_TYPE(type)	(((type) & 0x7) << 7)
48#define OP_CFG_ADDR_NUM(addr)		(((addr) & 0x7) << 4)
49#define OP_CFG_DUMMY_NUM(dummy)		((dummy) & 0xf)
50#define FMC_DATA_NUM			0x38
51#define FMC_DATA_NUM_CNT(cnt)		((cnt) & GENMASK(13, 0))
52#define FMC_OP				0x3c
53#define FMC_OP_DUMMY_EN			BIT(8)
54#define FMC_OP_CMD1_EN			BIT(7)
55#define FMC_OP_ADDR_EN			BIT(6)
56#define FMC_OP_WRITE_DATA_EN		BIT(5)
57#define FMC_OP_READ_DATA_EN		BIT(2)
58#define FMC_OP_READ_STATUS_EN		BIT(1)
59#define FMC_OP_REG_OP_START		BIT(0)
60#define FMC_DMA_LEN			0x40
61#define FMC_DMA_LEN_SET(len)		((len) & GENMASK(27, 0))
62#define FMC_DMA_SADDR_D0		0x4c
63#define HIFMC_DMA_MAX_LEN		(4096)
64#define HIFMC_DMA_MASK			(HIFMC_DMA_MAX_LEN - 1)
65#define FMC_OP_DMA			0x68
66#define OP_CTRL_RD_OPCODE(code)		(((code) & 0xff) << 16)
67#define OP_CTRL_WR_OPCODE(code)		(((code) & 0xff) << 8)
68#define OP_CTRL_RW_OP(op)		((op) << 1)
69#define OP_CTRL_DMA_OP_READY		BIT(0)
70#define FMC_OP_READ			0x0
71#define FMC_OP_WRITE			0x1
72#define FMC_WAIT_TIMEOUT		1000000
73
74enum hifmc_iftype {
75	IF_TYPE_STD,
76	IF_TYPE_DUAL,
77	IF_TYPE_DIO,
78	IF_TYPE_QUAD,
79	IF_TYPE_QIO,
80};
81
82struct hifmc_priv {
83	u32 chipselect;
84	u32 clkrate;
85	struct hifmc_host *host;
86};
87
88#define HIFMC_MAX_CHIP_NUM		2
89struct hifmc_host {
90	struct device *dev;
91	struct mutex lock;
92
93	void __iomem *regbase;
94	void __iomem *iobase;
95	struct clk *clk;
96	void *buffer;
97	dma_addr_t dma_buffer;
98
99	struct spi_nor	*nor[HIFMC_MAX_CHIP_NUM];
100	u32 num_chip;
101};
102
103static inline int hisi_spi_nor_wait_op_finish(struct hifmc_host *host)
104{
105	u32 reg;
106
107	return readl_poll_timeout(host->regbase + FMC_INT, reg,
108		(reg & FMC_INT_OP_DONE), 0, FMC_WAIT_TIMEOUT);
109}
110
111static int hisi_spi_nor_get_if_type(enum spi_nor_protocol proto)
112{
113	enum hifmc_iftype if_type;
114
115	switch (proto) {
116	case SNOR_PROTO_1_1_2:
117		if_type = IF_TYPE_DUAL;
118		break;
119	case SNOR_PROTO_1_2_2:
120		if_type = IF_TYPE_DIO;
121		break;
122	case SNOR_PROTO_1_1_4:
123		if_type = IF_TYPE_QUAD;
124		break;
125	case SNOR_PROTO_1_4_4:
126		if_type = IF_TYPE_QIO;
127		break;
128	case SNOR_PROTO_1_1_1:
129	default:
130		if_type = IF_TYPE_STD;
131		break;
132	}
133
134	return if_type;
135}
136
137static void hisi_spi_nor_init(struct hifmc_host *host)
138{
139	u32 reg;
140
141	reg = TIMING_CFG_TCSH(CS_HOLD_TIME)
142		| TIMING_CFG_TCSS(CS_SETUP_TIME)
143		| TIMING_CFG_TSHSL(CS_DESELECT_TIME);
144	writel(reg, host->regbase + FMC_SPI_TIMING_CFG);
145}
146
147static int hisi_spi_nor_prep(struct spi_nor *nor)
148{
149	struct hifmc_priv *priv = nor->priv;
150	struct hifmc_host *host = priv->host;
151	int ret;
152
153	mutex_lock(&host->lock);
154
155	ret = clk_set_rate(host->clk, priv->clkrate);
156	if (ret)
157		goto out;
158
159	ret = clk_prepare_enable(host->clk);
160	if (ret)
161		goto out;
162
163	return 0;
164
165out:
166	mutex_unlock(&host->lock);
167	return ret;
168}
169
170static void hisi_spi_nor_unprep(struct spi_nor *nor)
171{
172	struct hifmc_priv *priv = nor->priv;
173	struct hifmc_host *host = priv->host;
174
175	clk_disable_unprepare(host->clk);
176	mutex_unlock(&host->lock);
177}
178
179static int hisi_spi_nor_op_reg(struct spi_nor *nor,
180				u8 opcode, size_t len, u8 optype)
181{
182	struct hifmc_priv *priv = nor->priv;
183	struct hifmc_host *host = priv->host;
184	u32 reg;
185
186	reg = FMC_CMD_CMD1(opcode);
187	writel(reg, host->regbase + FMC_CMD);
188
189	reg = FMC_DATA_NUM_CNT(len);
190	writel(reg, host->regbase + FMC_DATA_NUM);
191
192	reg = OP_CFG_FM_CS(priv->chipselect);
193	writel(reg, host->regbase + FMC_OP_CFG);
194
195	writel(0xff, host->regbase + FMC_INT_CLR);
196	reg = FMC_OP_CMD1_EN | FMC_OP_REG_OP_START | optype;
197	writel(reg, host->regbase + FMC_OP);
198
199	return hisi_spi_nor_wait_op_finish(host);
200}
201
202static int hisi_spi_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
203				 size_t len)
204{
205	struct hifmc_priv *priv = nor->priv;
206	struct hifmc_host *host = priv->host;
207	int ret;
208
209	ret = hisi_spi_nor_op_reg(nor, opcode, len, FMC_OP_READ_DATA_EN);
210	if (ret)
211		return ret;
212
213	memcpy_fromio(buf, host->iobase, len);
214	return 0;
215}
216
217static int hisi_spi_nor_write_reg(struct spi_nor *nor, u8 opcode,
218				  const u8 *buf, size_t len)
219{
220	struct hifmc_priv *priv = nor->priv;
221	struct hifmc_host *host = priv->host;
222
223	if (len)
224		memcpy_toio(host->iobase, buf, len);
225
226	return hisi_spi_nor_op_reg(nor, opcode, len, FMC_OP_WRITE_DATA_EN);
227}
228
229static int hisi_spi_nor_dma_transfer(struct spi_nor *nor, loff_t start_off,
230		dma_addr_t dma_buf, size_t len, u8 op_type)
231{
232	struct hifmc_priv *priv = nor->priv;
233	struct hifmc_host *host = priv->host;
234	u8 if_type = 0;
235	u32 reg;
236
237	reg = readl(host->regbase + FMC_CFG);
238	reg &= ~(FMC_CFG_OP_MODE_MASK | SPI_NOR_ADDR_MODE_MASK);
239	reg |= FMC_CFG_OP_MODE_NORMAL;
240	reg |= (nor->addr_nbytes == 4) ? SPI_NOR_ADDR_MODE_4BYTES
241		: SPI_NOR_ADDR_MODE_3BYTES;
242	writel(reg, host->regbase + FMC_CFG);
243
244	writel(start_off, host->regbase + FMC_ADDRL);
245	writel(dma_buf, host->regbase + FMC_DMA_SADDR_D0);
246	writel(FMC_DMA_LEN_SET(len), host->regbase + FMC_DMA_LEN);
247
248	reg = OP_CFG_FM_CS(priv->chipselect);
249	if (op_type == FMC_OP_READ)
250		if_type = hisi_spi_nor_get_if_type(nor->read_proto);
251	else
252		if_type = hisi_spi_nor_get_if_type(nor->write_proto);
253	reg |= OP_CFG_MEM_IF_TYPE(if_type);
254	if (op_type == FMC_OP_READ)
255		reg |= OP_CFG_DUMMY_NUM(nor->read_dummy >> 3);
256	writel(reg, host->regbase + FMC_OP_CFG);
257
258	writel(0xff, host->regbase + FMC_INT_CLR);
259	reg = OP_CTRL_RW_OP(op_type) | OP_CTRL_DMA_OP_READY;
260	reg |= (op_type == FMC_OP_READ)
261		? OP_CTRL_RD_OPCODE(nor->read_opcode)
262		: OP_CTRL_WR_OPCODE(nor->program_opcode);
263	writel(reg, host->regbase + FMC_OP_DMA);
264
265	return hisi_spi_nor_wait_op_finish(host);
266}
267
268static ssize_t hisi_spi_nor_read(struct spi_nor *nor, loff_t from, size_t len,
269		u_char *read_buf)
270{
271	struct hifmc_priv *priv = nor->priv;
272	struct hifmc_host *host = priv->host;
273	size_t offset;
274	int ret;
275
276	for (offset = 0; offset < len; offset += HIFMC_DMA_MAX_LEN) {
277		size_t trans = min_t(size_t, HIFMC_DMA_MAX_LEN, len - offset);
278
279		ret = hisi_spi_nor_dma_transfer(nor,
280			from + offset, host->dma_buffer, trans, FMC_OP_READ);
281		if (ret) {
282			dev_warn(nor->dev, "DMA read timeout\n");
283			return ret;
284		}
285		memcpy(read_buf + offset, host->buffer, trans);
286	}
287
288	return len;
289}
290
291static ssize_t hisi_spi_nor_write(struct spi_nor *nor, loff_t to,
292			size_t len, const u_char *write_buf)
293{
294	struct hifmc_priv *priv = nor->priv;
295	struct hifmc_host *host = priv->host;
296	size_t offset;
297	int ret;
298
299	for (offset = 0; offset < len; offset += HIFMC_DMA_MAX_LEN) {
300		size_t trans = min_t(size_t, HIFMC_DMA_MAX_LEN, len - offset);
301
302		memcpy(host->buffer, write_buf + offset, trans);
303		ret = hisi_spi_nor_dma_transfer(nor,
304			to + offset, host->dma_buffer, trans, FMC_OP_WRITE);
305		if (ret) {
306			dev_warn(nor->dev, "DMA write timeout\n");
307			return ret;
308		}
309	}
310
311	return len;
312}
313
314static const struct spi_nor_controller_ops hisi_controller_ops = {
315	.prepare = hisi_spi_nor_prep,
316	.unprepare = hisi_spi_nor_unprep,
317	.read_reg = hisi_spi_nor_read_reg,
318	.write_reg = hisi_spi_nor_write_reg,
319	.read = hisi_spi_nor_read,
320	.write = hisi_spi_nor_write,
321};
322
323/*
324 * Get spi flash device information and register it as a mtd device.
325 */
326static int hisi_spi_nor_register(struct device_node *np,
327				struct hifmc_host *host)
328{
329	const struct spi_nor_hwcaps hwcaps = {
330		.mask = SNOR_HWCAPS_READ |
331			SNOR_HWCAPS_READ_FAST |
332			SNOR_HWCAPS_READ_1_1_2 |
333			SNOR_HWCAPS_READ_1_1_4 |
334			SNOR_HWCAPS_PP,
335	};
336	struct device *dev = host->dev;
337	struct spi_nor *nor;
338	struct hifmc_priv *priv;
339	struct mtd_info *mtd;
340	int ret;
341
342	nor = devm_kzalloc(dev, sizeof(*nor), GFP_KERNEL);
343	if (!nor)
344		return -ENOMEM;
345
346	nor->dev = dev;
347	spi_nor_set_flash_node(nor, np);
348
349	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
350	if (!priv)
351		return -ENOMEM;
352
353	ret = of_property_read_u32(np, "reg", &priv->chipselect);
354	if (ret) {
355		dev_err(dev, "There's no reg property for %pOF\n",
356			np);
357		return ret;
358	}
359
360	ret = of_property_read_u32(np, "spi-max-frequency",
361			&priv->clkrate);
362	if (ret) {
363		dev_err(dev, "There's no spi-max-frequency property for %pOF\n",
364			np);
365		return ret;
366	}
367	priv->host = host;
368	nor->priv = priv;
369	nor->controller_ops = &hisi_controller_ops;
370
371	ret = spi_nor_scan(nor, NULL, &hwcaps);
372	if (ret)
373		return ret;
374
375	mtd = &nor->mtd;
376	mtd->name = np->name;
377	ret = mtd_device_register(mtd, NULL, 0);
378	if (ret)
379		return ret;
380
381	host->nor[host->num_chip] = nor;
382	host->num_chip++;
383	return 0;
384}
385
386static void hisi_spi_nor_unregister_all(struct hifmc_host *host)
387{
388	int i;
389
390	for (i = 0; i < host->num_chip; i++)
391		mtd_device_unregister(&host->nor[i]->mtd);
392}
393
394static int hisi_spi_nor_register_all(struct hifmc_host *host)
395{
396	struct device *dev = host->dev;
397	struct device_node *np;
398	int ret;
399
400	for_each_available_child_of_node(dev->of_node, np) {
401		ret = hisi_spi_nor_register(np, host);
402		if (ret) {
403			of_node_put(np);
404			goto fail;
405		}
406
407		if (host->num_chip == HIFMC_MAX_CHIP_NUM) {
408			dev_warn(dev, "Flash device number exceeds the maximum chipselect number\n");
409			of_node_put(np);
410			break;
411		}
412	}
413
414	return 0;
415
416fail:
417	hisi_spi_nor_unregister_all(host);
418	return ret;
419}
420
421static int hisi_spi_nor_probe(struct platform_device *pdev)
422{
423	struct device *dev = &pdev->dev;
424	struct hifmc_host *host;
425	int ret;
426
427	host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
428	if (!host)
429		return -ENOMEM;
430
431	platform_set_drvdata(pdev, host);
432	host->dev = dev;
433
434	host->regbase = devm_platform_ioremap_resource_byname(pdev, "control");
435	if (IS_ERR(host->regbase))
436		return PTR_ERR(host->regbase);
437
438	host->iobase = devm_platform_ioremap_resource_byname(pdev, "memory");
439	if (IS_ERR(host->iobase))
440		return PTR_ERR(host->iobase);
441
442	host->clk = devm_clk_get(dev, NULL);
443	if (IS_ERR(host->clk))
444		return PTR_ERR(host->clk);
445
446	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
447	if (ret) {
448		dev_warn(dev, "Unable to set dma mask\n");
449		return ret;
450	}
451
452	host->buffer = dmam_alloc_coherent(dev, HIFMC_DMA_MAX_LEN,
453			&host->dma_buffer, GFP_KERNEL);
454	if (!host->buffer)
455		return -ENOMEM;
456
457	ret = clk_prepare_enable(host->clk);
458	if (ret)
459		return ret;
460
461	mutex_init(&host->lock);
462	hisi_spi_nor_init(host);
463	ret = hisi_spi_nor_register_all(host);
464	if (ret)
465		mutex_destroy(&host->lock);
466
467	clk_disable_unprepare(host->clk);
468	return ret;
469}
470
471static void hisi_spi_nor_remove(struct platform_device *pdev)
472{
473	struct hifmc_host *host = platform_get_drvdata(pdev);
474
475	hisi_spi_nor_unregister_all(host);
476	mutex_destroy(&host->lock);
477}
478
479static const struct of_device_id hisi_spi_nor_dt_ids[] = {
480	{ .compatible = "hisilicon,fmc-spi-nor"},
481	{ /* sentinel */ }
482};
483MODULE_DEVICE_TABLE(of, hisi_spi_nor_dt_ids);
484
485static struct platform_driver hisi_spi_nor_driver = {
486	.driver = {
487		.name	= "hisi-sfc",
488		.of_match_table = hisi_spi_nor_dt_ids,
489	},
490	.probe	= hisi_spi_nor_probe,
491	.remove_new = hisi_spi_nor_remove,
492};
493module_platform_driver(hisi_spi_nor_driver);
494
495MODULE_LICENSE("GPL v2");
496MODULE_DESCRIPTION("HiSilicon SPI Nor Flash Controller Driver");
497