1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * phy-zynqmp.c - PHY driver for Xilinx ZynqMP GT.
4  *
5  * Copyright (C) 2018-2020 Xilinx Inc.
6  *
7  * Author: Anurag Kumar Vulisha <anuragku@xilinx.com>
8  * Author: Subbaraya Sundeep <sundeep.lkml@gmail.com>
9  * Author: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
10  *
11  * This driver is tested for USB, SATA and Display Port currently.
12  * Other controllers PCIe and SGMII should also work but that is
13  * experimental as of now.
14  */
15 
16 #include <linux/clk.h>
17 #include <linux/delay.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/phy/phy.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 
26 #include <dt-bindings/phy/phy.h>
27 
28 /*
29  * Lane Registers
30  */
31 
32 /* TX De-emphasis parameters */
33 #define L0_TX_ANA_TM_18			0x0048
34 #define L0_TX_ANA_TM_118		0x01d8
35 #define L0_TX_ANA_TM_118_FORCE_17_0	BIT(0)
36 
37 /* DN Resistor calibration code parameters */
38 #define L0_TXPMA_ST_3			0x0b0c
39 #define L0_DN_CALIB_CODE		0x3f
40 
41 /* PMA control parameters */
42 #define L0_TXPMD_TM_45			0x0cb4
43 #define L0_TXPMD_TM_48			0x0cc0
44 #define L0_TXPMD_TM_45_OVER_DP_MAIN	BIT(0)
45 #define L0_TXPMD_TM_45_ENABLE_DP_MAIN	BIT(1)
46 #define L0_TXPMD_TM_45_OVER_DP_POST1	BIT(2)
47 #define L0_TXPMD_TM_45_ENABLE_DP_POST1	BIT(3)
48 #define L0_TXPMD_TM_45_OVER_DP_POST2	BIT(4)
49 #define L0_TXPMD_TM_45_ENABLE_DP_POST2	BIT(5)
50 
51 /* PCS control parameters */
52 #define L0_TM_DIG_6			0x106c
53 #define L0_TM_DIS_DESCRAMBLE_DECODER	0x0f
54 #define L0_TX_DIG_61			0x00f4
55 #define L0_TM_DISABLE_SCRAMBLE_ENCODER	0x0f
56 
57 /* PLL Test Mode register parameters */
58 #define L0_TM_PLL_DIG_37		0x2094
59 #define L0_TM_COARSE_CODE_LIMIT		0x10
60 
61 /* PLL SSC step size offsets */
62 #define L0_PLL_SS_STEPS_0_LSB		0x2368
63 #define L0_PLL_SS_STEPS_1_MSB		0x236c
64 #define L0_PLL_SS_STEP_SIZE_0_LSB	0x2370
65 #define L0_PLL_SS_STEP_SIZE_1		0x2374
66 #define L0_PLL_SS_STEP_SIZE_2		0x2378
67 #define L0_PLL_SS_STEP_SIZE_3_MSB	0x237c
68 #define L0_PLL_STATUS_READ_1		0x23e4
69 
70 /* SSC step size parameters */
71 #define STEP_SIZE_0_MASK		0xff
72 #define STEP_SIZE_1_MASK		0xff
73 #define STEP_SIZE_2_MASK		0xff
74 #define STEP_SIZE_3_MASK		0x3
75 #define STEP_SIZE_SHIFT			8
76 #define FORCE_STEP_SIZE			0x10
77 #define FORCE_STEPS			0x20
78 #define STEPS_0_MASK			0xff
79 #define STEPS_1_MASK			0x07
80 
81 /* Reference clock selection parameters */
82 #define L0_Ln_REF_CLK_SEL(n)		(0x2860 + (n) * 4)
83 #define L0_REF_CLK_SEL_MASK		0x8f
84 
85 /* Calibration digital logic parameters */
86 #define L3_TM_CALIB_DIG19		0xec4c
87 #define L3_CALIB_DONE_STATUS		0xef14
88 #define L3_TM_CALIB_DIG18		0xec48
89 #define L3_TM_CALIB_DIG19_NSW		0x07
90 #define L3_TM_CALIB_DIG18_NSW		0xe0
91 #define L3_TM_OVERRIDE_NSW_CODE         0x20
92 #define L3_CALIB_DONE			0x02
93 #define L3_NSW_SHIFT			5
94 #define L3_NSW_PIPE_SHIFT		4
95 #define L3_NSW_CALIB_SHIFT		3
96 
97 #define PHY_REG_OFFSET			0x4000
98 
99 /*
100  * Global Registers
101  */
102 
103 /* Refclk selection parameters */
104 #define PLL_REF_SEL(n)			(0x10000 + (n) * 4)
105 #define PLL_FREQ_MASK			0x1f
106 #define PLL_STATUS_LOCKED		0x10
107 
108 /* Inter Connect Matrix parameters */
109 #define ICM_CFG0			0x10010
110 #define ICM_CFG1			0x10014
111 #define ICM_CFG0_L0_MASK		0x07
112 #define ICM_CFG0_L1_MASK		0x70
113 #define ICM_CFG1_L2_MASK		0x07
114 #define ICM_CFG2_L3_MASK		0x70
115 #define ICM_CFG_SHIFT			4
116 
117 /* Inter Connect Matrix allowed protocols */
118 #define ICM_PROTOCOL_PD			0x0
119 #define ICM_PROTOCOL_PCIE		0x1
120 #define ICM_PROTOCOL_SATA		0x2
121 #define ICM_PROTOCOL_USB		0x3
122 #define ICM_PROTOCOL_DP			0x4
123 #define ICM_PROTOCOL_SGMII		0x5
124 
125 /* Test Mode common reset control  parameters */
126 #define TM_CMN_RST			0x10018
127 #define TM_CMN_RST_EN			0x1
128 #define TM_CMN_RST_SET			0x2
129 #define TM_CMN_RST_MASK			0x3
130 
131 /* Bus width parameters */
132 #define TX_PROT_BUS_WIDTH		0x10040
133 #define RX_PROT_BUS_WIDTH		0x10044
134 #define PROT_BUS_WIDTH_10		0x0
135 #define PROT_BUS_WIDTH_20		0x1
136 #define PROT_BUS_WIDTH_40		0x2
137 #define PROT_BUS_WIDTH_SHIFT		2
138 
139 /* Number of GT lanes */
140 #define NUM_LANES			4
141 
142 /* SIOU SATA control register */
143 #define SATA_CONTROL_OFFSET		0x0100
144 
145 /* Total number of controllers */
146 #define CONTROLLERS_PER_LANE		5
147 
148 /* Protocol Type parameters */
149 #define XPSGTR_TYPE_USB0		0  /* USB controller 0 */
150 #define XPSGTR_TYPE_USB1		1  /* USB controller 1 */
151 #define XPSGTR_TYPE_SATA_0		2  /* SATA controller lane 0 */
152 #define XPSGTR_TYPE_SATA_1		3  /* SATA controller lane 1 */
153 #define XPSGTR_TYPE_PCIE_0		4  /* PCIe controller lane 0 */
154 #define XPSGTR_TYPE_PCIE_1		5  /* PCIe controller lane 1 */
155 #define XPSGTR_TYPE_PCIE_2		6  /* PCIe controller lane 2 */
156 #define XPSGTR_TYPE_PCIE_3		7  /* PCIe controller lane 3 */
157 #define XPSGTR_TYPE_DP_0		8  /* Display Port controller lane 0 */
158 #define XPSGTR_TYPE_DP_1		9  /* Display Port controller lane 1 */
159 #define XPSGTR_TYPE_SGMII0		10 /* Ethernet SGMII controller 0 */
160 #define XPSGTR_TYPE_SGMII1		11 /* Ethernet SGMII controller 1 */
161 #define XPSGTR_TYPE_SGMII2		12 /* Ethernet SGMII controller 2 */
162 #define XPSGTR_TYPE_SGMII3		13 /* Ethernet SGMII controller 3 */
163 
164 /* Timeout values */
165 #define TIMEOUT_US			1000
166 
167 struct xpsgtr_dev;
168 
169 /**
170  * struct xpsgtr_ssc - structure to hold SSC settings for a lane
171  * @refclk_rate: PLL reference clock frequency
172  * @pll_ref_clk: value to be written to register for corresponding ref clk rate
173  * @steps: number of steps of SSC (Spread Spectrum Clock)
174  * @step_size: step size of each step
175  */
176 struct xpsgtr_ssc {
177 	u32 refclk_rate;
178 	u8  pll_ref_clk;
179 	u32 steps;
180 	u32 step_size;
181 };
182 
183 /**
184  * struct xpsgtr_phy - representation of a lane
185  * @phy: pointer to the kernel PHY device
186  * @type: controller which uses this lane
187  * @lane: lane number
188  * @protocol: protocol in which the lane operates
189  * @skip_phy_init: skip phy_init() if true
190  * @dev: pointer to the xpsgtr_dev instance
191  * @refclk: reference clock index
192  */
193 struct xpsgtr_phy {
194 	struct phy *phy;
195 	u8 type;
196 	u8 lane;
197 	u8 protocol;
198 	bool skip_phy_init;
199 	struct xpsgtr_dev *dev;
200 	unsigned int refclk;
201 };
202 
203 /**
204  * struct xpsgtr_dev - representation of a ZynMP GT device
205  * @dev: pointer to device
206  * @serdes: serdes base address
207  * @siou: siou base address
208  * @gtr_mutex: mutex for locking
209  * @phys: PHY lanes
210  * @refclk_sscs: spread spectrum settings for the reference clocks
211  * @clk: reference clocks
212  * @tx_term_fix: fix for GT issue
213  * @saved_icm_cfg0: stored value of ICM CFG0 register
214  * @saved_icm_cfg1: stored value of ICM CFG1 register
215  */
216 struct xpsgtr_dev {
217 	struct device *dev;
218 	void __iomem *serdes;
219 	void __iomem *siou;
220 	struct mutex gtr_mutex; /* mutex for locking */
221 	struct xpsgtr_phy phys[NUM_LANES];
222 	const struct xpsgtr_ssc *refclk_sscs[NUM_LANES];
223 	struct clk *clk[NUM_LANES];
224 	bool tx_term_fix;
225 	unsigned int saved_icm_cfg0;
226 	unsigned int saved_icm_cfg1;
227 };
228 
229 /*
230  * Configuration Data
231  */
232 
233 /* lookup table to hold all settings needed for a ref clock frequency */
234 static const struct xpsgtr_ssc ssc_lookup[] = {
235 	{  19200000, 0x05,  608, 264020 },
236 	{  20000000, 0x06,  634, 243454 },
237 	{  24000000, 0x07,  760, 168973 },
238 	{  26000000, 0x08,  824, 143860 },
239 	{  27000000, 0x09,  856,  86551 },
240 	{  38400000, 0x0a, 1218,  65896 },
241 	{  40000000, 0x0b,  634, 243454 },
242 	{  52000000, 0x0c,  824, 143860 },
243 	{ 100000000, 0x0d, 1058,  87533 },
244 	{ 108000000, 0x0e,  856,  86551 },
245 	{ 125000000, 0x0f,  992, 119497 },
246 	{ 135000000, 0x10, 1070,  55393 },
247 	{ 150000000, 0x11,  792, 187091 }
248 };
249 
250 /*
251  * I/O Accessors
252  */
253 
xpsgtr_read(struct xpsgtr_dev * gtr_dev,u32 reg)254 static inline u32 xpsgtr_read(struct xpsgtr_dev *gtr_dev, u32 reg)
255 {
256 	return readl(gtr_dev->serdes + reg);
257 }
258 
xpsgtr_write(struct xpsgtr_dev * gtr_dev,u32 reg,u32 value)259 static inline void xpsgtr_write(struct xpsgtr_dev *gtr_dev, u32 reg, u32 value)
260 {
261 	writel(value, gtr_dev->serdes + reg);
262 }
263 
xpsgtr_clr_set(struct xpsgtr_dev * gtr_dev,u32 reg,u32 clr,u32 set)264 static inline void xpsgtr_clr_set(struct xpsgtr_dev *gtr_dev, u32 reg,
265 				  u32 clr, u32 set)
266 {
267 	u32 value = xpsgtr_read(gtr_dev, reg);
268 
269 	value &= ~clr;
270 	value |= set;
271 	xpsgtr_write(gtr_dev, reg, value);
272 }
273 
xpsgtr_read_phy(struct xpsgtr_phy * gtr_phy,u32 reg)274 static inline u32 xpsgtr_read_phy(struct xpsgtr_phy *gtr_phy, u32 reg)
275 {
276 	void __iomem *addr = gtr_phy->dev->serdes
277 			   + gtr_phy->lane * PHY_REG_OFFSET + reg;
278 
279 	return readl(addr);
280 }
281 
xpsgtr_write_phy(struct xpsgtr_phy * gtr_phy,u32 reg,u32 value)282 static inline void xpsgtr_write_phy(struct xpsgtr_phy *gtr_phy,
283 				    u32 reg, u32 value)
284 {
285 	void __iomem *addr = gtr_phy->dev->serdes
286 			   + gtr_phy->lane * PHY_REG_OFFSET + reg;
287 
288 	writel(value, addr);
289 }
290 
xpsgtr_clr_set_phy(struct xpsgtr_phy * gtr_phy,u32 reg,u32 clr,u32 set)291 static inline void xpsgtr_clr_set_phy(struct xpsgtr_phy *gtr_phy,
292 				      u32 reg, u32 clr, u32 set)
293 {
294 	void __iomem *addr = gtr_phy->dev->serdes
295 			   + gtr_phy->lane * PHY_REG_OFFSET + reg;
296 
297 	writel((readl(addr) & ~clr) | set, addr);
298 }
299 
300 /*
301  * Hardware Configuration
302  */
303 
304 /* Wait for the PLL to lock (with a timeout). */
xpsgtr_wait_pll_lock(struct phy * phy)305 static int xpsgtr_wait_pll_lock(struct phy *phy)
306 {
307 	struct xpsgtr_phy *gtr_phy = phy_get_drvdata(phy);
308 	struct xpsgtr_dev *gtr_dev = gtr_phy->dev;
309 	unsigned int timeout = TIMEOUT_US;
310 	int ret;
311 
312 	dev_dbg(gtr_dev->dev, "Waiting for PLL lock\n");
313 
314 	while (1) {
315 		u32 reg = xpsgtr_read_phy(gtr_phy, L0_PLL_STATUS_READ_1);
316 
317 		if ((reg & PLL_STATUS_LOCKED) == PLL_STATUS_LOCKED) {
318 			ret = 0;
319 			break;
320 		}
321 
322 		if (--timeout == 0) {
323 			ret = -ETIMEDOUT;
324 			break;
325 		}
326 
327 		udelay(1);
328 	}
329 
330 	if (ret == -ETIMEDOUT)
331 		dev_err(gtr_dev->dev,
332 			"lane %u (type %u, protocol %u): PLL lock timeout\n",
333 			gtr_phy->lane, gtr_phy->type, gtr_phy->protocol);
334 
335 	return ret;
336 }
337 
338 /* Configure PLL and spread-sprectrum clock. */
xpsgtr_configure_pll(struct xpsgtr_phy * gtr_phy)339 static void xpsgtr_configure_pll(struct xpsgtr_phy *gtr_phy)
340 {
341 	const struct xpsgtr_ssc *ssc;
342 	u32 step_size;
343 
344 	ssc = gtr_phy->dev->refclk_sscs[gtr_phy->refclk];
345 	step_size = ssc->step_size;
346 
347 	xpsgtr_clr_set(gtr_phy->dev, PLL_REF_SEL(gtr_phy->lane),
348 		       PLL_FREQ_MASK, ssc->pll_ref_clk);
349 
350 	/* Enable lane clock sharing, if required */
351 	if (gtr_phy->refclk != gtr_phy->lane) {
352 		/* Lane3 Ref Clock Selection Register */
353 		xpsgtr_clr_set(gtr_phy->dev, L0_Ln_REF_CLK_SEL(gtr_phy->lane),
354 			       L0_REF_CLK_SEL_MASK, 1 << gtr_phy->refclk);
355 	}
356 
357 	/* SSC step size [7:0] */
358 	xpsgtr_clr_set_phy(gtr_phy, L0_PLL_SS_STEP_SIZE_0_LSB,
359 			   STEP_SIZE_0_MASK, step_size & STEP_SIZE_0_MASK);
360 
361 	/* SSC step size [15:8] */
362 	step_size >>= STEP_SIZE_SHIFT;
363 	xpsgtr_clr_set_phy(gtr_phy, L0_PLL_SS_STEP_SIZE_1,
364 			   STEP_SIZE_1_MASK, step_size & STEP_SIZE_1_MASK);
365 
366 	/* SSC step size [23:16] */
367 	step_size >>= STEP_SIZE_SHIFT;
368 	xpsgtr_clr_set_phy(gtr_phy, L0_PLL_SS_STEP_SIZE_2,
369 			   STEP_SIZE_2_MASK, step_size & STEP_SIZE_2_MASK);
370 
371 	/* SSC steps [7:0] */
372 	xpsgtr_clr_set_phy(gtr_phy, L0_PLL_SS_STEPS_0_LSB,
373 			   STEPS_0_MASK, ssc->steps & STEPS_0_MASK);
374 
375 	/* SSC steps [10:8] */
376 	xpsgtr_clr_set_phy(gtr_phy, L0_PLL_SS_STEPS_1_MSB,
377 			   STEPS_1_MASK,
378 			   (ssc->steps >> STEP_SIZE_SHIFT) & STEPS_1_MASK);
379 
380 	/* SSC step size [24:25] */
381 	step_size >>= STEP_SIZE_SHIFT;
382 	xpsgtr_clr_set_phy(gtr_phy, L0_PLL_SS_STEP_SIZE_3_MSB,
383 			   STEP_SIZE_3_MASK, (step_size & STEP_SIZE_3_MASK) |
384 			   FORCE_STEP_SIZE | FORCE_STEPS);
385 }
386 
387 /* Configure the lane protocol. */
xpsgtr_lane_set_protocol(struct xpsgtr_phy * gtr_phy)388 static void xpsgtr_lane_set_protocol(struct xpsgtr_phy *gtr_phy)
389 {
390 	struct xpsgtr_dev *gtr_dev = gtr_phy->dev;
391 	u8 protocol = gtr_phy->protocol;
392 
393 	switch (gtr_phy->lane) {
394 	case 0:
395 		xpsgtr_clr_set(gtr_dev, ICM_CFG0, ICM_CFG0_L0_MASK, protocol);
396 		break;
397 	case 1:
398 		xpsgtr_clr_set(gtr_dev, ICM_CFG0, ICM_CFG0_L1_MASK,
399 			       protocol << ICM_CFG_SHIFT);
400 		break;
401 	case 2:
402 		xpsgtr_clr_set(gtr_dev, ICM_CFG1, ICM_CFG0_L0_MASK, protocol);
403 		break;
404 	case 3:
405 		xpsgtr_clr_set(gtr_dev, ICM_CFG1, ICM_CFG0_L1_MASK,
406 			       protocol << ICM_CFG_SHIFT);
407 		break;
408 	default:
409 		/* We already checked 0 <= lane <= 3 */
410 		break;
411 	}
412 }
413 
414 /* Bypass (de)scrambler and 8b/10b decoder and encoder. */
xpsgtr_bypass_scrambler_8b10b(struct xpsgtr_phy * gtr_phy)415 static void xpsgtr_bypass_scrambler_8b10b(struct xpsgtr_phy *gtr_phy)
416 {
417 	xpsgtr_write_phy(gtr_phy, L0_TM_DIG_6, L0_TM_DIS_DESCRAMBLE_DECODER);
418 	xpsgtr_write_phy(gtr_phy, L0_TX_DIG_61, L0_TM_DISABLE_SCRAMBLE_ENCODER);
419 }
420 
421 /* DP-specific initialization. */
xpsgtr_phy_init_dp(struct xpsgtr_phy * gtr_phy)422 static void xpsgtr_phy_init_dp(struct xpsgtr_phy *gtr_phy)
423 {
424 	xpsgtr_write_phy(gtr_phy, L0_TXPMD_TM_45,
425 			 L0_TXPMD_TM_45_OVER_DP_MAIN |
426 			 L0_TXPMD_TM_45_ENABLE_DP_MAIN |
427 			 L0_TXPMD_TM_45_OVER_DP_POST1 |
428 			 L0_TXPMD_TM_45_OVER_DP_POST2 |
429 			 L0_TXPMD_TM_45_ENABLE_DP_POST2);
430 	xpsgtr_write_phy(gtr_phy, L0_TX_ANA_TM_118,
431 			 L0_TX_ANA_TM_118_FORCE_17_0);
432 }
433 
434 /* SATA-specific initialization. */
xpsgtr_phy_init_sata(struct xpsgtr_phy * gtr_phy)435 static void xpsgtr_phy_init_sata(struct xpsgtr_phy *gtr_phy)
436 {
437 	struct xpsgtr_dev *gtr_dev = gtr_phy->dev;
438 
439 	xpsgtr_bypass_scrambler_8b10b(gtr_phy);
440 
441 	writel(gtr_phy->lane, gtr_dev->siou + SATA_CONTROL_OFFSET);
442 }
443 
444 /* SGMII-specific initialization. */
xpsgtr_phy_init_sgmii(struct xpsgtr_phy * gtr_phy)445 static void xpsgtr_phy_init_sgmii(struct xpsgtr_phy *gtr_phy)
446 {
447 	struct xpsgtr_dev *gtr_dev = gtr_phy->dev;
448 
449 	/* Set SGMII protocol TX and RX bus width to 10 bits. */
450 	xpsgtr_write(gtr_dev, TX_PROT_BUS_WIDTH,
451 		     PROT_BUS_WIDTH_10 << (gtr_phy->lane * PROT_BUS_WIDTH_SHIFT));
452 	xpsgtr_write(gtr_dev, RX_PROT_BUS_WIDTH,
453 		     PROT_BUS_WIDTH_10 << (gtr_phy->lane * PROT_BUS_WIDTH_SHIFT));
454 
455 	xpsgtr_bypass_scrambler_8b10b(gtr_phy);
456 }
457 
458 /* Configure TX de-emphasis and margining for DP. */
xpsgtr_phy_configure_dp(struct xpsgtr_phy * gtr_phy,unsigned int pre,unsigned int voltage)459 static void xpsgtr_phy_configure_dp(struct xpsgtr_phy *gtr_phy, unsigned int pre,
460 				    unsigned int voltage)
461 {
462 	static const u8 voltage_swing[4][4] = {
463 		{ 0x2a, 0x27, 0x24, 0x20 },
464 		{ 0x27, 0x23, 0x20, 0xff },
465 		{ 0x24, 0x20, 0xff, 0xff },
466 		{ 0xff, 0xff, 0xff, 0xff }
467 	};
468 	static const u8 pre_emphasis[4][4] = {
469 		{ 0x02, 0x02, 0x02, 0x02 },
470 		{ 0x01, 0x01, 0x01, 0xff },
471 		{ 0x00, 0x00, 0xff, 0xff },
472 		{ 0xff, 0xff, 0xff, 0xff }
473 	};
474 
475 	xpsgtr_write_phy(gtr_phy, L0_TXPMD_TM_48, voltage_swing[pre][voltage]);
476 	xpsgtr_write_phy(gtr_phy, L0_TX_ANA_TM_18, pre_emphasis[pre][voltage]);
477 }
478 
479 /*
480  * PHY Operations
481  */
482 
xpsgtr_phy_init_required(struct xpsgtr_phy * gtr_phy)483 static bool xpsgtr_phy_init_required(struct xpsgtr_phy *gtr_phy)
484 {
485 	/*
486 	 * As USB may save the snapshot of the states during hibernation, doing
487 	 * phy_init() will put the USB controller into reset, resulting in the
488 	 * losing of the saved snapshot. So try to avoid phy_init() for USB
489 	 * except when gtr_phy->skip_phy_init is false (this happens when FPD is
490 	 * shutdown during suspend or when gt lane is changed from current one)
491 	 */
492 	if (gtr_phy->protocol == ICM_PROTOCOL_USB && gtr_phy->skip_phy_init)
493 		return false;
494 	else
495 		return true;
496 }
497 
498 /*
499  * There is a functional issue in the GT. The TX termination resistance can be
500  * out of spec due to a issue in the calibration logic. This is the workaround
501  * to fix it, required for XCZU9EG silicon.
502  */
xpsgtr_phy_tx_term_fix(struct xpsgtr_phy * gtr_phy)503 static int xpsgtr_phy_tx_term_fix(struct xpsgtr_phy *gtr_phy)
504 {
505 	struct xpsgtr_dev *gtr_dev = gtr_phy->dev;
506 	u32 timeout = TIMEOUT_US;
507 	u32 nsw;
508 
509 	/* Enabling Test Mode control for CMN Rest */
510 	xpsgtr_clr_set(gtr_dev, TM_CMN_RST, TM_CMN_RST_MASK, TM_CMN_RST_SET);
511 
512 	/* Set Test Mode reset */
513 	xpsgtr_clr_set(gtr_dev, TM_CMN_RST, TM_CMN_RST_MASK, TM_CMN_RST_EN);
514 
515 	xpsgtr_write(gtr_dev, L3_TM_CALIB_DIG18, 0x00);
516 	xpsgtr_write(gtr_dev, L3_TM_CALIB_DIG19, L3_TM_OVERRIDE_NSW_CODE);
517 
518 	/*
519 	 * As a part of work around sequence for PMOS calibration fix,
520 	 * we need to configure any lane ICM_CFG to valid protocol. This
521 	 * will deassert the CMN_Resetn signal.
522 	 */
523 	xpsgtr_lane_set_protocol(gtr_phy);
524 
525 	/* Clear Test Mode reset */
526 	xpsgtr_clr_set(gtr_dev, TM_CMN_RST, TM_CMN_RST_MASK, TM_CMN_RST_SET);
527 
528 	dev_dbg(gtr_dev->dev, "calibrating...\n");
529 
530 	do {
531 		u32 reg = xpsgtr_read(gtr_dev, L3_CALIB_DONE_STATUS);
532 
533 		if ((reg & L3_CALIB_DONE) == L3_CALIB_DONE)
534 			break;
535 
536 		if (!--timeout) {
537 			dev_err(gtr_dev->dev, "calibration time out\n");
538 			return -ETIMEDOUT;
539 		}
540 
541 		udelay(1);
542 	} while (timeout > 0);
543 
544 	dev_dbg(gtr_dev->dev, "calibration done\n");
545 
546 	/* Reading NMOS Register Code */
547 	nsw = xpsgtr_read(gtr_dev, L0_TXPMA_ST_3) & L0_DN_CALIB_CODE;
548 
549 	/* Set Test Mode reset */
550 	xpsgtr_clr_set(gtr_dev, TM_CMN_RST, TM_CMN_RST_MASK, TM_CMN_RST_EN);
551 
552 	/* Writing NMOS register values back [5:3] */
553 	xpsgtr_write(gtr_dev, L3_TM_CALIB_DIG19, nsw >> L3_NSW_CALIB_SHIFT);
554 
555 	/* Writing NMOS register value [2:0] */
556 	xpsgtr_write(gtr_dev, L3_TM_CALIB_DIG18,
557 		     ((nsw & L3_TM_CALIB_DIG19_NSW) << L3_NSW_SHIFT) |
558 		     (1 << L3_NSW_PIPE_SHIFT));
559 
560 	/* Clear Test Mode reset */
561 	xpsgtr_clr_set(gtr_dev, TM_CMN_RST, TM_CMN_RST_MASK, TM_CMN_RST_SET);
562 
563 	return 0;
564 }
565 
xpsgtr_phy_init(struct phy * phy)566 static int xpsgtr_phy_init(struct phy *phy)
567 {
568 	struct xpsgtr_phy *gtr_phy = phy_get_drvdata(phy);
569 	struct xpsgtr_dev *gtr_dev = gtr_phy->dev;
570 	int ret = 0;
571 
572 	mutex_lock(&gtr_dev->gtr_mutex);
573 
574 	/* Skip initialization if not required. */
575 	if (!xpsgtr_phy_init_required(gtr_phy))
576 		goto out;
577 
578 	if (gtr_dev->tx_term_fix) {
579 		ret = xpsgtr_phy_tx_term_fix(gtr_phy);
580 		if (ret < 0)
581 			goto out;
582 
583 		gtr_dev->tx_term_fix = false;
584 	}
585 
586 	/* Enable coarse code saturation limiting logic. */
587 	xpsgtr_write_phy(gtr_phy, L0_TM_PLL_DIG_37, L0_TM_COARSE_CODE_LIMIT);
588 
589 	/*
590 	 * Configure the PLL, the lane protocol, and perform protocol-specific
591 	 * initialization.
592 	 */
593 	xpsgtr_configure_pll(gtr_phy);
594 	xpsgtr_lane_set_protocol(gtr_phy);
595 
596 	switch (gtr_phy->protocol) {
597 	case ICM_PROTOCOL_DP:
598 		xpsgtr_phy_init_dp(gtr_phy);
599 		break;
600 
601 	case ICM_PROTOCOL_SATA:
602 		xpsgtr_phy_init_sata(gtr_phy);
603 		break;
604 
605 	case ICM_PROTOCOL_SGMII:
606 		xpsgtr_phy_init_sgmii(gtr_phy);
607 		break;
608 	}
609 
610 out:
611 	mutex_unlock(&gtr_dev->gtr_mutex);
612 	return ret;
613 }
614 
xpsgtr_phy_exit(struct phy * phy)615 static int xpsgtr_phy_exit(struct phy *phy)
616 {
617 	struct xpsgtr_phy *gtr_phy = phy_get_drvdata(phy);
618 
619 	gtr_phy->skip_phy_init = false;
620 
621 	return 0;
622 }
623 
xpsgtr_phy_power_on(struct phy * phy)624 static int xpsgtr_phy_power_on(struct phy *phy)
625 {
626 	struct xpsgtr_phy *gtr_phy = phy_get_drvdata(phy);
627 	int ret = 0;
628 
629 	/* Skip initialization if not required. */
630 	if (!xpsgtr_phy_init_required(gtr_phy))
631 		return ret;
632 	/*
633 	 * Wait for the PLL to lock. For DP, only wait on DP0 to avoid
634 	 * cumulating waits for both lanes. The user is expected to initialize
635 	 * lane 0 last.
636 	 */
637 	if (gtr_phy->protocol != ICM_PROTOCOL_DP ||
638 	    gtr_phy->type == XPSGTR_TYPE_DP_0)
639 		ret = xpsgtr_wait_pll_lock(phy);
640 
641 	return ret;
642 }
643 
xpsgtr_phy_configure(struct phy * phy,union phy_configure_opts * opts)644 static int xpsgtr_phy_configure(struct phy *phy, union phy_configure_opts *opts)
645 {
646 	struct xpsgtr_phy *gtr_phy = phy_get_drvdata(phy);
647 
648 	if (gtr_phy->protocol != ICM_PROTOCOL_DP)
649 		return 0;
650 
651 	xpsgtr_phy_configure_dp(gtr_phy, opts->dp.pre[0], opts->dp.voltage[0]);
652 
653 	return 0;
654 }
655 
656 static const struct phy_ops xpsgtr_phyops = {
657 	.init		= xpsgtr_phy_init,
658 	.exit		= xpsgtr_phy_exit,
659 	.power_on	= xpsgtr_phy_power_on,
660 	.configure	= xpsgtr_phy_configure,
661 	.owner		= THIS_MODULE,
662 };
663 
664 /*
665  * OF Xlate Support
666  */
667 
668 /* Set the lane type and protocol based on the PHY type and instance number. */
xpsgtr_set_lane_type(struct xpsgtr_phy * gtr_phy,u8 phy_type,unsigned int phy_instance)669 static int xpsgtr_set_lane_type(struct xpsgtr_phy *gtr_phy, u8 phy_type,
670 				unsigned int phy_instance)
671 {
672 	unsigned int num_phy_types;
673 	const int *phy_types;
674 
675 	switch (phy_type) {
676 	case PHY_TYPE_SATA: {
677 		static const int types[] = {
678 			XPSGTR_TYPE_SATA_0,
679 			XPSGTR_TYPE_SATA_1,
680 		};
681 
682 		phy_types = types;
683 		num_phy_types = ARRAY_SIZE(types);
684 		gtr_phy->protocol = ICM_PROTOCOL_SATA;
685 		break;
686 	}
687 	case PHY_TYPE_USB3: {
688 		static const int types[] = {
689 			XPSGTR_TYPE_USB0,
690 			XPSGTR_TYPE_USB1,
691 		};
692 
693 		phy_types = types;
694 		num_phy_types = ARRAY_SIZE(types);
695 		gtr_phy->protocol = ICM_PROTOCOL_USB;
696 		break;
697 	}
698 	case PHY_TYPE_DP: {
699 		static const int types[] = {
700 			XPSGTR_TYPE_DP_0,
701 			XPSGTR_TYPE_DP_1,
702 		};
703 
704 		phy_types = types;
705 		num_phy_types = ARRAY_SIZE(types);
706 		gtr_phy->protocol = ICM_PROTOCOL_DP;
707 		break;
708 	}
709 	case PHY_TYPE_PCIE: {
710 		static const int types[] = {
711 			XPSGTR_TYPE_PCIE_0,
712 			XPSGTR_TYPE_PCIE_1,
713 			XPSGTR_TYPE_PCIE_2,
714 			XPSGTR_TYPE_PCIE_3,
715 		};
716 
717 		phy_types = types;
718 		num_phy_types = ARRAY_SIZE(types);
719 		gtr_phy->protocol = ICM_PROTOCOL_PCIE;
720 		break;
721 	}
722 	case PHY_TYPE_SGMII: {
723 		static const int types[] = {
724 			XPSGTR_TYPE_SGMII0,
725 			XPSGTR_TYPE_SGMII1,
726 			XPSGTR_TYPE_SGMII2,
727 			XPSGTR_TYPE_SGMII3,
728 		};
729 
730 		phy_types = types;
731 		num_phy_types = ARRAY_SIZE(types);
732 		gtr_phy->protocol = ICM_PROTOCOL_SGMII;
733 		break;
734 	}
735 	default:
736 		return -EINVAL;
737 	}
738 
739 	if (phy_instance >= num_phy_types)
740 		return -EINVAL;
741 
742 	gtr_phy->type = phy_types[phy_instance];
743 	return 0;
744 }
745 
746 /*
747  * Valid combinations of controllers and lanes (Interconnect Matrix).
748  */
749 static const unsigned int icm_matrix[NUM_LANES][CONTROLLERS_PER_LANE] = {
750 	{ XPSGTR_TYPE_PCIE_0, XPSGTR_TYPE_SATA_0, XPSGTR_TYPE_USB0,
751 		XPSGTR_TYPE_DP_1, XPSGTR_TYPE_SGMII0 },
752 	{ XPSGTR_TYPE_PCIE_1, XPSGTR_TYPE_SATA_1, XPSGTR_TYPE_USB0,
753 		XPSGTR_TYPE_DP_0, XPSGTR_TYPE_SGMII1 },
754 	{ XPSGTR_TYPE_PCIE_2, XPSGTR_TYPE_SATA_0, XPSGTR_TYPE_USB0,
755 		XPSGTR_TYPE_DP_1, XPSGTR_TYPE_SGMII2 },
756 	{ XPSGTR_TYPE_PCIE_3, XPSGTR_TYPE_SATA_1, XPSGTR_TYPE_USB1,
757 		XPSGTR_TYPE_DP_0, XPSGTR_TYPE_SGMII3 }
758 };
759 
760 /* Translate OF phandle and args to PHY instance. */
xpsgtr_xlate(struct device * dev,struct of_phandle_args * args)761 static struct phy *xpsgtr_xlate(struct device *dev,
762 				struct of_phandle_args *args)
763 {
764 	struct xpsgtr_dev *gtr_dev = dev_get_drvdata(dev);
765 	struct xpsgtr_phy *gtr_phy;
766 	unsigned int phy_instance;
767 	unsigned int phy_lane;
768 	unsigned int phy_type;
769 	unsigned int refclk;
770 	unsigned int i;
771 	int ret;
772 
773 	if (args->args_count != 4) {
774 		dev_err(dev, "Invalid number of cells in 'phy' property\n");
775 		return ERR_PTR(-EINVAL);
776 	}
777 
778 	/*
779 	 * Get the PHY parameters from the OF arguments and derive the lane
780 	 * type.
781 	 */
782 	phy_lane = args->args[0];
783 	if (phy_lane >= ARRAY_SIZE(gtr_dev->phys)) {
784 		dev_err(dev, "Invalid lane number %u\n", phy_lane);
785 		return ERR_PTR(-ENODEV);
786 	}
787 
788 	gtr_phy = &gtr_dev->phys[phy_lane];
789 	phy_type = args->args[1];
790 	phy_instance = args->args[2];
791 
792 	ret = xpsgtr_set_lane_type(gtr_phy, phy_type, phy_instance);
793 	if (ret < 0) {
794 		dev_err(gtr_dev->dev, "Invalid PHY type and/or instance\n");
795 		return ERR_PTR(ret);
796 	}
797 
798 	refclk = args->args[3];
799 	if (refclk >= ARRAY_SIZE(gtr_dev->refclk_sscs) ||
800 	    !gtr_dev->refclk_sscs[refclk]) {
801 		dev_err(dev, "Invalid reference clock number %u\n", refclk);
802 		return ERR_PTR(-EINVAL);
803 	}
804 
805 	gtr_phy->refclk = refclk;
806 
807 	/*
808 	 * Ensure that the Interconnect Matrix is obeyed, i.e a given lane type
809 	 * is allowed to operate on the lane.
810 	 */
811 	for (i = 0; i < CONTROLLERS_PER_LANE; i++) {
812 		if (icm_matrix[phy_lane][i] == gtr_phy->type)
813 			return gtr_phy->phy;
814 	}
815 
816 	return ERR_PTR(-EINVAL);
817 }
818 
819 /*
820  * Power Management
821  */
822 
xpsgtr_suspend(struct device * dev)823 static int __maybe_unused xpsgtr_suspend(struct device *dev)
824 {
825 	struct xpsgtr_dev *gtr_dev = dev_get_drvdata(dev);
826 	unsigned int i;
827 
828 	/* Save the snapshot ICM_CFG registers. */
829 	gtr_dev->saved_icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0);
830 	gtr_dev->saved_icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1);
831 
832 	for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++)
833 		clk_disable_unprepare(gtr_dev->clk[i]);
834 
835 	return 0;
836 }
837 
xpsgtr_resume(struct device * dev)838 static int __maybe_unused xpsgtr_resume(struct device *dev)
839 {
840 	struct xpsgtr_dev *gtr_dev = dev_get_drvdata(dev);
841 	unsigned int icm_cfg0, icm_cfg1;
842 	unsigned int i;
843 	bool skip_phy_init;
844 	int err;
845 
846 	for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) {
847 		err = clk_prepare_enable(gtr_dev->clk[i]);
848 		if (err)
849 			goto err_clk_put;
850 	}
851 
852 	icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0);
853 	icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1);
854 
855 	/* Return if no GT lanes got configured before suspend. */
856 	if (!gtr_dev->saved_icm_cfg0 && !gtr_dev->saved_icm_cfg1)
857 		return 0;
858 
859 	/* Check if the ICM configurations changed after suspend. */
860 	if (icm_cfg0 == gtr_dev->saved_icm_cfg0 &&
861 	    icm_cfg1 == gtr_dev->saved_icm_cfg1)
862 		skip_phy_init = true;
863 	else
864 		skip_phy_init = false;
865 
866 	/* Update the skip_phy_init for all gtr_phy instances. */
867 	for (i = 0; i < ARRAY_SIZE(gtr_dev->phys); i++)
868 		gtr_dev->phys[i].skip_phy_init = skip_phy_init;
869 
870 	return 0;
871 
872 err_clk_put:
873 	while (i--)
874 		clk_disable_unprepare(gtr_dev->clk[i]);
875 
876 	return err;
877 }
878 
879 static const struct dev_pm_ops xpsgtr_pm_ops = {
880 	SET_SYSTEM_SLEEP_PM_OPS(xpsgtr_suspend, xpsgtr_resume)
881 };
882 
883 /*
884  * Probe & Platform Driver
885  */
886 
xpsgtr_get_ref_clocks(struct xpsgtr_dev * gtr_dev)887 static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev)
888 {
889 	unsigned int refclk;
890 	int ret;
891 
892 	for (refclk = 0; refclk < ARRAY_SIZE(gtr_dev->refclk_sscs); ++refclk) {
893 		unsigned long rate;
894 		unsigned int i;
895 		struct clk *clk;
896 		char name[8];
897 
898 		snprintf(name, sizeof(name), "ref%u", refclk);
899 		clk = devm_clk_get_optional(gtr_dev->dev, name);
900 		if (IS_ERR(clk)) {
901 			ret = dev_err_probe(gtr_dev->dev, PTR_ERR(clk),
902 					    "Failed to get reference clock %u\n",
903 					    refclk);
904 			goto err_clk_put;
905 		}
906 
907 		if (!clk)
908 			continue;
909 
910 		ret = clk_prepare_enable(clk);
911 		if (ret)
912 			goto err_clk_put;
913 
914 		gtr_dev->clk[refclk] = clk;
915 
916 		/*
917 		 * Get the spread spectrum (SSC) settings for the reference
918 		 * clock rate.
919 		 */
920 		rate = clk_get_rate(clk);
921 
922 		for (i = 0 ; i < ARRAY_SIZE(ssc_lookup); i++) {
923 			if (rate == ssc_lookup[i].refclk_rate) {
924 				gtr_dev->refclk_sscs[refclk] = &ssc_lookup[i];
925 				break;
926 			}
927 		}
928 
929 		if (i == ARRAY_SIZE(ssc_lookup)) {
930 			dev_err(gtr_dev->dev,
931 				"Invalid rate %lu for reference clock %u\n",
932 				rate, refclk);
933 			ret = -EINVAL;
934 			goto err_clk_put;
935 		}
936 	}
937 
938 	return 0;
939 
940 err_clk_put:
941 	while (refclk--)
942 		clk_disable_unprepare(gtr_dev->clk[refclk]);
943 
944 	return ret;
945 }
946 
xpsgtr_probe(struct platform_device * pdev)947 static int xpsgtr_probe(struct platform_device *pdev)
948 {
949 	struct device_node *np = pdev->dev.of_node;
950 	struct xpsgtr_dev *gtr_dev;
951 	struct phy_provider *provider;
952 	unsigned int port;
953 	unsigned int i;
954 	int ret;
955 
956 	gtr_dev = devm_kzalloc(&pdev->dev, sizeof(*gtr_dev), GFP_KERNEL);
957 	if (!gtr_dev)
958 		return -ENOMEM;
959 
960 	gtr_dev->dev = &pdev->dev;
961 	platform_set_drvdata(pdev, gtr_dev);
962 
963 	mutex_init(&gtr_dev->gtr_mutex);
964 
965 	if (of_device_is_compatible(np, "xlnx,zynqmp-psgtr"))
966 		gtr_dev->tx_term_fix =
967 			of_property_read_bool(np, "xlnx,tx-termination-fix");
968 
969 	/* Acquire resources. */
970 	gtr_dev->serdes = devm_platform_ioremap_resource_byname(pdev, "serdes");
971 	if (IS_ERR(gtr_dev->serdes))
972 		return PTR_ERR(gtr_dev->serdes);
973 
974 	gtr_dev->siou = devm_platform_ioremap_resource_byname(pdev, "siou");
975 	if (IS_ERR(gtr_dev->siou))
976 		return PTR_ERR(gtr_dev->siou);
977 
978 	ret = xpsgtr_get_ref_clocks(gtr_dev);
979 	if (ret)
980 		return ret;
981 
982 	/* Create PHYs. */
983 	for (port = 0; port < ARRAY_SIZE(gtr_dev->phys); ++port) {
984 		struct xpsgtr_phy *gtr_phy = &gtr_dev->phys[port];
985 		struct phy *phy;
986 
987 		gtr_phy->lane = port;
988 		gtr_phy->dev = gtr_dev;
989 
990 		phy = devm_phy_create(&pdev->dev, np, &xpsgtr_phyops);
991 		if (IS_ERR(phy)) {
992 			dev_err(&pdev->dev, "failed to create PHY\n");
993 			ret = PTR_ERR(phy);
994 			goto err_clk_put;
995 		}
996 
997 		gtr_phy->phy = phy;
998 		phy_set_drvdata(phy, gtr_phy);
999 	}
1000 
1001 	/* Register the PHY provider. */
1002 	provider = devm_of_phy_provider_register(&pdev->dev, xpsgtr_xlate);
1003 	if (IS_ERR(provider)) {
1004 		dev_err(&pdev->dev, "registering provider failed\n");
1005 		ret = PTR_ERR(provider);
1006 		goto err_clk_put;
1007 	}
1008 	return 0;
1009 
1010 err_clk_put:
1011 	for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++)
1012 		clk_disable_unprepare(gtr_dev->clk[i]);
1013 
1014 	return ret;
1015 }
1016 
1017 static const struct of_device_id xpsgtr_of_match[] = {
1018 	{ .compatible = "xlnx,zynqmp-psgtr", },
1019 	{ .compatible = "xlnx,zynqmp-psgtr-v1.1", },
1020 	{},
1021 };
1022 MODULE_DEVICE_TABLE(of, xpsgtr_of_match);
1023 
1024 static struct platform_driver xpsgtr_driver = {
1025 	.probe = xpsgtr_probe,
1026 	.driver = {
1027 		.name = "xilinx-psgtr",
1028 		.of_match_table	= xpsgtr_of_match,
1029 		.pm =  &xpsgtr_pm_ops,
1030 	},
1031 };
1032 
1033 module_platform_driver(xpsgtr_driver);
1034 
1035 MODULE_AUTHOR("Xilinx Inc.");
1036 MODULE_LICENSE("GPL v2");
1037 MODULE_DESCRIPTION("Xilinx ZynqMP High speed Gigabit Transceiver");
1038