1// SPDX-License-Identifier: GPL-2.0
2/*
3 * FPGA Manager Driver for Altera Arria10 SoCFPGA
4 *
5 * Copyright (C) 2015-2016 Altera Corporation
6 */
7#include <linux/clk.h>
8#include <linux/device.h>
9#include <linux/delay.h>
10#include <linux/fpga/fpga-mgr.h>
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/of_address.h>
14#include <linux/regmap.h>
15
16#define A10_FPGAMGR_DCLKCNT_OFST				0x08
17#define A10_FPGAMGR_DCLKSTAT_OFST				0x0c
18#define A10_FPGAMGR_IMGCFG_CTL_00_OFST				0x70
19#define A10_FPGAMGR_IMGCFG_CTL_01_OFST				0x74
20#define A10_FPGAMGR_IMGCFG_CTL_02_OFST				0x78
21#define A10_FPGAMGR_IMGCFG_STAT_OFST				0x80
22
23#define A10_FPGAMGR_DCLKSTAT_DCLKDONE				BIT(0)
24
25#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NCONFIG		BIT(0)
26#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NSTATUS		BIT(1)
27#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_CONDONE		BIT(2)
28#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NCONFIG			BIT(8)
29#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NSTATUS_OE		BIT(16)
30#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_CONDONE_OE		BIT(24)
31
32#define A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG		BIT(0)
33#define A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST		BIT(16)
34#define A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE			BIT(24)
35
36#define A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL			BIT(0)
37#define A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_MASK		(BIT(16) | BIT(17))
38#define A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_SHIFT			16
39#define A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH			BIT(24)
40#define A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH_SHIFT		24
41
42#define A10_FPGAMGR_IMGCFG_STAT_F2S_CRC_ERROR			BIT(0)
43#define A10_FPGAMGR_IMGCFG_STAT_F2S_EARLY_USERMODE		BIT(1)
44#define A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE			BIT(2)
45#define A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN			BIT(4)
46#define A10_FPGAMGR_IMGCFG_STAT_F2S_CONDONE_PIN			BIT(6)
47#define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY			BIT(9)
48#define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_DONE			BIT(10)
49#define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR			BIT(11)
50#define A10_FPGAMGR_IMGCFG_STAT_F2S_NCONFIG_PIN			BIT(12)
51#define A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_MASK	(BIT(16) | BIT(17) | BIT(18))
52#define A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_SHIFT		        16
53
54/* FPGA CD Ratio Value */
55#define CDRATIO_x1						0x0
56#define CDRATIO_x2						0x1
57#define CDRATIO_x4						0x2
58#define CDRATIO_x8						0x3
59
60/* Configuration width 16/32 bit */
61#define CFGWDTH_32						1
62#define CFGWDTH_16						0
63
64/*
65 * struct a10_fpga_priv - private data for fpga manager
66 * @regmap: regmap for register access
67 * @fpga_data_addr: iomap for single address data register to FPGA
68 * @clk: clock
69 */
70struct a10_fpga_priv {
71	struct regmap *regmap;
72	void __iomem *fpga_data_addr;
73	struct clk *clk;
74};
75
76static bool socfpga_a10_fpga_writeable_reg(struct device *dev, unsigned int reg)
77{
78	switch (reg) {
79	case A10_FPGAMGR_DCLKCNT_OFST:
80	case A10_FPGAMGR_DCLKSTAT_OFST:
81	case A10_FPGAMGR_IMGCFG_CTL_00_OFST:
82	case A10_FPGAMGR_IMGCFG_CTL_01_OFST:
83	case A10_FPGAMGR_IMGCFG_CTL_02_OFST:
84		return true;
85	}
86	return false;
87}
88
89static bool socfpga_a10_fpga_readable_reg(struct device *dev, unsigned int reg)
90{
91	switch (reg) {
92	case A10_FPGAMGR_DCLKCNT_OFST:
93	case A10_FPGAMGR_DCLKSTAT_OFST:
94	case A10_FPGAMGR_IMGCFG_CTL_00_OFST:
95	case A10_FPGAMGR_IMGCFG_CTL_01_OFST:
96	case A10_FPGAMGR_IMGCFG_CTL_02_OFST:
97	case A10_FPGAMGR_IMGCFG_STAT_OFST:
98		return true;
99	}
100	return false;
101}
102
103static const struct regmap_config socfpga_a10_fpga_regmap_config = {
104	.reg_bits = 32,
105	.reg_stride = 4,
106	.val_bits = 32,
107	.writeable_reg = socfpga_a10_fpga_writeable_reg,
108	.readable_reg = socfpga_a10_fpga_readable_reg,
109	.max_register = A10_FPGAMGR_IMGCFG_STAT_OFST,
110	.cache_type = REGCACHE_NONE,
111};
112
113/*
114 * from the register map description of cdratio in imgcfg_ctrl_02:
115 *  Normal Configuration    : 32bit Passive Parallel
116 *  Partial Reconfiguration : 16bit Passive Parallel
117 */
118static void socfpga_a10_fpga_set_cfg_width(struct a10_fpga_priv *priv,
119					   int width)
120{
121	width <<= A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH_SHIFT;
122
123	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
124			   A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH, width);
125}
126
127static void socfpga_a10_fpga_generate_dclks(struct a10_fpga_priv *priv,
128					    u32 count)
129{
130	u32 val;
131
132	/* Clear any existing DONE status. */
133	regmap_write(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST,
134		     A10_FPGAMGR_DCLKSTAT_DCLKDONE);
135
136	/* Issue the DCLK regmap. */
137	regmap_write(priv->regmap, A10_FPGAMGR_DCLKCNT_OFST, count);
138
139	/* wait till the dclkcnt done */
140	regmap_read_poll_timeout(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST, val,
141				 val, 1, 100);
142
143	/* Clear DONE status. */
144	regmap_write(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST,
145		     A10_FPGAMGR_DCLKSTAT_DCLKDONE);
146}
147
148#define RBF_ENCRYPTION_MODE_OFFSET		69
149#define RBF_DECOMPRESS_OFFSET			229
150
151static int socfpga_a10_fpga_encrypted(u32 *buf32, size_t buf32_size)
152{
153	if (buf32_size < RBF_ENCRYPTION_MODE_OFFSET + 1)
154		return -EINVAL;
155
156	/* Is the bitstream encrypted? */
157	return ((buf32[RBF_ENCRYPTION_MODE_OFFSET] >> 2) & 3) != 0;
158}
159
160static int socfpga_a10_fpga_compressed(u32 *buf32, size_t buf32_size)
161{
162	if (buf32_size < RBF_DECOMPRESS_OFFSET + 1)
163		return -EINVAL;
164
165	/* Is the bitstream compressed? */
166	return !((buf32[RBF_DECOMPRESS_OFFSET] >> 1) & 1);
167}
168
169static unsigned int socfpga_a10_fpga_get_cd_ratio(unsigned int cfg_width,
170						  bool encrypt, bool compress)
171{
172	unsigned int cd_ratio;
173
174	/*
175	 * cd ratio is dependent on cfg width and whether the bitstream
176	 * is encrypted and/or compressed.
177	 *
178	 * | width | encr. | compr. | cd ratio |
179	 * |  16   |   0   |   0    |     1    |
180	 * |  16   |   0   |   1    |     4    |
181	 * |  16   |   1   |   0    |     2    |
182	 * |  16   |   1   |   1    |     4    |
183	 * |  32   |   0   |   0    |     1    |
184	 * |  32   |   0   |   1    |     8    |
185	 * |  32   |   1   |   0    |     4    |
186	 * |  32   |   1   |   1    |     8    |
187	 */
188	if (!compress && !encrypt)
189		return CDRATIO_x1;
190
191	if (compress)
192		cd_ratio = CDRATIO_x4;
193	else
194		cd_ratio = CDRATIO_x2;
195
196	/* If 32 bit, double the cd ratio by incrementing the field  */
197	if (cfg_width == CFGWDTH_32)
198		cd_ratio += 1;
199
200	return cd_ratio;
201}
202
203static int socfpga_a10_fpga_set_cdratio(struct fpga_manager *mgr,
204					unsigned int cfg_width,
205					const char *buf, size_t count)
206{
207	struct a10_fpga_priv *priv = mgr->priv;
208	unsigned int cd_ratio;
209	int encrypt, compress;
210
211	encrypt = socfpga_a10_fpga_encrypted((u32 *)buf, count / 4);
212	if (encrypt < 0)
213		return -EINVAL;
214
215	compress = socfpga_a10_fpga_compressed((u32 *)buf, count / 4);
216	if (compress < 0)
217		return -EINVAL;
218
219	cd_ratio = socfpga_a10_fpga_get_cd_ratio(cfg_width, encrypt, compress);
220
221	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
222			   A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_MASK,
223			   cd_ratio << A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_SHIFT);
224
225	return 0;
226}
227
228static u32 socfpga_a10_fpga_read_stat(struct a10_fpga_priv *priv)
229{
230	u32 val;
231
232	regmap_read(priv->regmap, A10_FPGAMGR_IMGCFG_STAT_OFST, &val);
233
234	return val;
235}
236
237static int socfpga_a10_fpga_wait_for_pr_ready(struct a10_fpga_priv *priv)
238{
239	u32 reg, i;
240
241	for (i = 0; i < 10 ; i++) {
242		reg = socfpga_a10_fpga_read_stat(priv);
243
244		if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR)
245			return -EINVAL;
246
247		if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY)
248			return 0;
249	}
250
251	return -ETIMEDOUT;
252}
253
254static int socfpga_a10_fpga_wait_for_pr_done(struct a10_fpga_priv *priv)
255{
256	u32 reg, i;
257
258	for (i = 0; i < 10 ; i++) {
259		reg = socfpga_a10_fpga_read_stat(priv);
260
261		if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR)
262			return -EINVAL;
263
264		if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_DONE)
265			return 0;
266	}
267
268	return -ETIMEDOUT;
269}
270
271/* Start the FPGA programming by initialize the FPGA Manager */
272static int socfpga_a10_fpga_write_init(struct fpga_manager *mgr,
273				       struct fpga_image_info *info,
274				       const char *buf, size_t count)
275{
276	struct a10_fpga_priv *priv = mgr->priv;
277	unsigned int cfg_width;
278	u32 msel, stat, mask;
279	int ret;
280
281	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG)
282		cfg_width = CFGWDTH_16;
283	else
284		return -EINVAL;
285
286	/* Check for passive parallel (msel == 000 or 001) */
287	msel = socfpga_a10_fpga_read_stat(priv);
288	msel &= A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_MASK;
289	msel >>= A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_SHIFT;
290	if ((msel != 0) && (msel != 1)) {
291		dev_dbg(&mgr->dev, "Fail: invalid msel=%d\n", msel);
292		return -EINVAL;
293	}
294
295	/* Make sure no external devices are interfering */
296	stat = socfpga_a10_fpga_read_stat(priv);
297	mask = A10_FPGAMGR_IMGCFG_STAT_F2S_NCONFIG_PIN |
298	       A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN;
299	if ((stat & mask) != mask)
300		return -EINVAL;
301
302	/* Set cfg width */
303	socfpga_a10_fpga_set_cfg_width(priv, cfg_width);
304
305	/* Determine cd ratio from bitstream header and set cd ratio */
306	ret = socfpga_a10_fpga_set_cdratio(mgr, cfg_width, buf, count);
307	if (ret)
308		return ret;
309
310	/*
311	 * Clear s2f_nce to enable chip select.  Leave pr_request
312	 * unasserted and override disabled.
313	 */
314	regmap_write(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
315		     A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG);
316
317	/* Set cfg_ctrl to enable s2f dclk and data */
318	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
319			   A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL,
320			   A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL);
321
322	/*
323	 * Disable overrides not needed for pr.
324	 * s2f_config==1 leaves reset deasseted.
325	 */
326	regmap_write(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_00_OFST,
327		     A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NCONFIG |
328		     A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NSTATUS |
329		     A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_CONDONE |
330		     A10_FPGAMGR_IMGCFG_CTL_00_S2F_NCONFIG);
331
332	/* Enable override for data, dclk, nce, and pr_request to CSS */
333	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
334			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG, 0);
335
336	/* Send some clocks to clear out any errors */
337	socfpga_a10_fpga_generate_dclks(priv, 256);
338
339	/* Assert pr_request */
340	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
341			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST,
342			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST);
343
344	/* Provide 2048 DCLKs before starting the config data streaming. */
345	socfpga_a10_fpga_generate_dclks(priv, 0x7ff);
346
347	/* Wait for pr_ready */
348	return socfpga_a10_fpga_wait_for_pr_ready(priv);
349}
350
351/*
352 * write data to the FPGA data register
353 */
354static int socfpga_a10_fpga_write(struct fpga_manager *mgr, const char *buf,
355				  size_t count)
356{
357	struct a10_fpga_priv *priv = mgr->priv;
358	u32 *buffer_32 = (u32 *)buf;
359	size_t i = 0;
360
361	if (count <= 0)
362		return -EINVAL;
363
364	/* Write out the complete 32-bit chunks */
365	while (count >= sizeof(u32)) {
366		writel(buffer_32[i++], priv->fpga_data_addr);
367		count -= sizeof(u32);
368	}
369
370	/* Write out remaining non 32-bit chunks */
371	switch (count) {
372	case 3:
373		writel(buffer_32[i++] & 0x00ffffff, priv->fpga_data_addr);
374		break;
375	case 2:
376		writel(buffer_32[i++] & 0x0000ffff, priv->fpga_data_addr);
377		break;
378	case 1:
379		writel(buffer_32[i++] & 0x000000ff, priv->fpga_data_addr);
380		break;
381	case 0:
382		break;
383	default:
384		/* This will never happen */
385		return -EFAULT;
386	}
387
388	return 0;
389}
390
391static int socfpga_a10_fpga_write_complete(struct fpga_manager *mgr,
392					   struct fpga_image_info *info)
393{
394	struct a10_fpga_priv *priv = mgr->priv;
395	u32 reg;
396	int ret;
397
398	/* Wait for pr_done */
399	ret = socfpga_a10_fpga_wait_for_pr_done(priv);
400
401	/* Clear pr_request */
402	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
403			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST, 0);
404
405	/* Send some clocks to clear out any errors */
406	socfpga_a10_fpga_generate_dclks(priv, 256);
407
408	/* Disable s2f dclk and data */
409	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
410			   A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL, 0);
411
412	/* Deassert chip select */
413	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
414			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE,
415			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE);
416
417	/* Disable data, dclk, nce, and pr_request override to CSS */
418	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
419			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG,
420			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG);
421
422	/* Return any errors regarding pr_done or pr_error */
423	if (ret)
424		return ret;
425
426	/* Final check */
427	reg = socfpga_a10_fpga_read_stat(priv);
428
429	if (((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE) == 0) ||
430	    ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_CONDONE_PIN) == 0) ||
431	    ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN) == 0)) {
432		dev_dbg(&mgr->dev,
433			"Timeout in final check. Status=%08xf\n", reg);
434		return -ETIMEDOUT;
435	}
436
437	return 0;
438}
439
440static enum fpga_mgr_states socfpga_a10_fpga_state(struct fpga_manager *mgr)
441{
442	struct a10_fpga_priv *priv = mgr->priv;
443	u32 reg = socfpga_a10_fpga_read_stat(priv);
444
445	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE)
446		return FPGA_MGR_STATE_OPERATING;
447
448	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY)
449		return FPGA_MGR_STATE_WRITE;
450
451	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_CRC_ERROR)
452		return FPGA_MGR_STATE_WRITE_COMPLETE_ERR;
453
454	if ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN) == 0)
455		return FPGA_MGR_STATE_RESET;
456
457	return FPGA_MGR_STATE_UNKNOWN;
458}
459
460static const struct fpga_manager_ops socfpga_a10_fpga_mgr_ops = {
461	.initial_header_size = (RBF_DECOMPRESS_OFFSET + 1) * 4,
462	.state = socfpga_a10_fpga_state,
463	.write_init = socfpga_a10_fpga_write_init,
464	.write = socfpga_a10_fpga_write,
465	.write_complete = socfpga_a10_fpga_write_complete,
466};
467
468static int socfpga_a10_fpga_probe(struct platform_device *pdev)
469{
470	struct device *dev = &pdev->dev;
471	struct a10_fpga_priv *priv;
472	void __iomem *reg_base;
473	struct fpga_manager *mgr;
474	int ret;
475
476	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
477	if (!priv)
478		return -ENOMEM;
479
480	/* First mmio base is for register access */
481	reg_base = devm_platform_ioremap_resource(pdev, 0);
482	if (IS_ERR(reg_base))
483		return PTR_ERR(reg_base);
484
485	/* Second mmio base is for writing FPGA image data */
486	priv->fpga_data_addr = devm_platform_ioremap_resource(pdev, 1);
487	if (IS_ERR(priv->fpga_data_addr))
488		return PTR_ERR(priv->fpga_data_addr);
489
490	/* regmap for register access */
491	priv->regmap = devm_regmap_init_mmio(dev, reg_base,
492					     &socfpga_a10_fpga_regmap_config);
493	if (IS_ERR(priv->regmap))
494		return -ENODEV;
495
496	priv->clk = devm_clk_get(dev, NULL);
497	if (IS_ERR(priv->clk)) {
498		dev_err(dev, "no clock specified\n");
499		return PTR_ERR(priv->clk);
500	}
501
502	ret = clk_prepare_enable(priv->clk);
503	if (ret) {
504		dev_err(dev, "could not enable clock\n");
505		return -EBUSY;
506	}
507
508	mgr = fpga_mgr_register(dev, "SoCFPGA Arria10 FPGA Manager",
509				&socfpga_a10_fpga_mgr_ops, priv);
510	if (IS_ERR(mgr)) {
511		clk_disable_unprepare(priv->clk);
512		return PTR_ERR(mgr);
513	}
514
515	platform_set_drvdata(pdev, mgr);
516
517	return 0;
518}
519
520static void socfpga_a10_fpga_remove(struct platform_device *pdev)
521{
522	struct fpga_manager *mgr = platform_get_drvdata(pdev);
523	struct a10_fpga_priv *priv = mgr->priv;
524
525	fpga_mgr_unregister(mgr);
526	clk_disable_unprepare(priv->clk);
527}
528
529static const struct of_device_id socfpga_a10_fpga_of_match[] = {
530	{ .compatible = "altr,socfpga-a10-fpga-mgr", },
531	{},
532};
533
534MODULE_DEVICE_TABLE(of, socfpga_a10_fpga_of_match);
535
536static struct platform_driver socfpga_a10_fpga_driver = {
537	.probe = socfpga_a10_fpga_probe,
538	.remove_new = socfpga_a10_fpga_remove,
539	.driver = {
540		.name	= "socfpga_a10_fpga_manager",
541		.of_match_table = socfpga_a10_fpga_of_match,
542	},
543};
544
545module_platform_driver(socfpga_a10_fpga_driver);
546
547MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
548MODULE_DESCRIPTION("SoCFPGA Arria10 FPGA Manager");
549MODULE_LICENSE("GPL v2");
550