1 /*
2  * Qualcomm Atheros IPQ806x GMAC glue layer
3  *
4  * Copyright (C) 2015 The Linux Foundation
5  *
6  * Permission to use, copy, modify, and/or distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <linux/device.h>
20 #include <linux/platform_device.h>
21 #include <linux/phy.h>
22 #include <linux/regmap.h>
23 #include <linux/clk.h>
24 #include <linux/reset.h>
25 #include <linux/of_net.h>
26 #include <linux/mfd/syscon.h>
27 #include <linux/stmmac.h>
28 #include <linux/of_mdio.h>
29 #include <linux/module.h>
30 
31 #include "stmmac_platform.h"
32 
33 #define NSS_COMMON_CLK_GATE			0x8
34 #define NSS_COMMON_CLK_GATE_PTP_EN(x)		BIT(0x10 + x)
35 #define NSS_COMMON_CLK_GATE_RGMII_RX_EN(x)	BIT(0x9 + (x * 2))
36 #define NSS_COMMON_CLK_GATE_RGMII_TX_EN(x)	BIT(0x8 + (x * 2))
37 #define NSS_COMMON_CLK_GATE_GMII_RX_EN(x)	BIT(0x4 + x)
38 #define NSS_COMMON_CLK_GATE_GMII_TX_EN(x)	BIT(0x0 + x)
39 
40 #define NSS_COMMON_CLK_DIV0			0xC
41 #define NSS_COMMON_CLK_DIV_OFFSET(x)		(x * 8)
42 #define NSS_COMMON_CLK_DIV_MASK			0x7f
43 
44 #define NSS_COMMON_CLK_SRC_CTRL			0x14
45 #define NSS_COMMON_CLK_SRC_CTRL_OFFSET(x)	(x)
46 /* Mode is coded on 1 bit but is different depending on the MAC ID:
47  * MAC0: QSGMII=0 RGMII=1
48  * MAC1: QSGMII=0 SGMII=0 RGMII=1
49  * MAC2 & MAC3: QSGMII=0 SGMII=1
50  */
51 #define NSS_COMMON_CLK_SRC_CTRL_RGMII(x)	1
52 #define NSS_COMMON_CLK_SRC_CTRL_SGMII(x)	((x >= 2) ? 1 : 0)
53 
54 #define NSS_COMMON_MACSEC_CTL			0x28
55 #define NSS_COMMON_MACSEC_CTL_EXT_BYPASS_EN(x)	(1 << x)
56 
57 #define NSS_COMMON_GMAC_CTL(x)			(0x30 + (x * 4))
58 #define NSS_COMMON_GMAC_CTL_CSYS_REQ		BIT(19)
59 #define NSS_COMMON_GMAC_CTL_PHY_IFACE_SEL	BIT(16)
60 #define NSS_COMMON_GMAC_CTL_IFG_LIMIT_OFFSET	8
61 #define NSS_COMMON_GMAC_CTL_IFG_OFFSET		0
62 #define NSS_COMMON_GMAC_CTL_IFG_MASK		0x3f
63 
64 #define NSS_COMMON_CLK_DIV_RGMII_1000		1
65 #define NSS_COMMON_CLK_DIV_RGMII_100		9
66 #define NSS_COMMON_CLK_DIV_RGMII_10		99
67 #define NSS_COMMON_CLK_DIV_SGMII_1000		0
68 #define NSS_COMMON_CLK_DIV_SGMII_100		4
69 #define NSS_COMMON_CLK_DIV_SGMII_10		49
70 
71 #define QSGMII_PCS_MODE_CTL			0x68
72 #define QSGMII_PCS_MODE_CTL_AUTONEG_EN(x)	BIT((x * 8) + 7)
73 
74 #define QSGMII_PCS_CAL_LCKDT_CTL		0x120
75 #define QSGMII_PCS_CAL_LCKDT_CTL_RST		BIT(19)
76 
77 /* Only GMAC1/2/3 support SGMII and their CTL register are not contiguous */
78 #define QSGMII_PHY_SGMII_CTL(x)			((x == 1) ? 0x134 : \
79 						 (0x13c + (4 * (x - 2))))
80 #define QSGMII_PHY_CDR_EN			BIT(0)
81 #define QSGMII_PHY_RX_FRONT_EN			BIT(1)
82 #define QSGMII_PHY_RX_SIGNAL_DETECT_EN		BIT(2)
83 #define QSGMII_PHY_TX_DRIVER_EN			BIT(3)
84 #define QSGMII_PHY_QSGMII_EN			BIT(7)
85 #define QSGMII_PHY_PHASE_LOOP_GAIN_OFFSET	12
86 #define QSGMII_PHY_PHASE_LOOP_GAIN_MASK		0x7
87 #define QSGMII_PHY_RX_DC_BIAS_OFFSET		18
88 #define QSGMII_PHY_RX_DC_BIAS_MASK		0x3
89 #define QSGMII_PHY_RX_INPUT_EQU_OFFSET		20
90 #define QSGMII_PHY_RX_INPUT_EQU_MASK		0x3
91 #define QSGMII_PHY_CDR_PI_SLEW_OFFSET		22
92 #define QSGMII_PHY_CDR_PI_SLEW_MASK		0x3
93 #define QSGMII_PHY_TX_DRV_AMP_OFFSET		28
94 #define QSGMII_PHY_TX_DRV_AMP_MASK		0xf
95 
96 struct ipq806x_gmac {
97 	struct platform_device *pdev;
98 	struct regmap *nss_common;
99 	struct regmap *qsgmii_csr;
100 	uint32_t id;
101 	struct clk *core_clk;
102 	phy_interface_t phy_mode;
103 };
104 
105 static int get_clk_div_sgmii(struct ipq806x_gmac *gmac, unsigned int speed)
106 {
107 	struct device *dev = &gmac->pdev->dev;
108 	int div;
109 
110 	switch (speed) {
111 	case SPEED_1000:
112 		div = NSS_COMMON_CLK_DIV_SGMII_1000;
113 		break;
114 
115 	case SPEED_100:
116 		div = NSS_COMMON_CLK_DIV_SGMII_100;
117 		break;
118 
119 	case SPEED_10:
120 		div = NSS_COMMON_CLK_DIV_SGMII_10;
121 		break;
122 
123 	default:
124 		dev_err(dev, "Speed %dMbps not supported in SGMII\n", speed);
125 		return -EINVAL;
126 	}
127 
128 	return div;
129 }
130 
131 static int get_clk_div_rgmii(struct ipq806x_gmac *gmac, unsigned int speed)
132 {
133 	struct device *dev = &gmac->pdev->dev;
134 	int div;
135 
136 	switch (speed) {
137 	case SPEED_1000:
138 		div = NSS_COMMON_CLK_DIV_RGMII_1000;
139 		break;
140 
141 	case SPEED_100:
142 		div = NSS_COMMON_CLK_DIV_RGMII_100;
143 		break;
144 
145 	case SPEED_10:
146 		div = NSS_COMMON_CLK_DIV_RGMII_10;
147 		break;
148 
149 	default:
150 		dev_err(dev, "Speed %dMbps not supported in RGMII\n", speed);
151 		return -EINVAL;
152 	}
153 
154 	return div;
155 }
156 
157 static int ipq806x_gmac_set_speed(struct ipq806x_gmac *gmac, unsigned int speed)
158 {
159 	uint32_t clk_bits, val;
160 	int div;
161 
162 	switch (gmac->phy_mode) {
163 	case PHY_INTERFACE_MODE_RGMII:
164 		div = get_clk_div_rgmii(gmac, speed);
165 		clk_bits = NSS_COMMON_CLK_GATE_RGMII_RX_EN(gmac->id) |
166 			   NSS_COMMON_CLK_GATE_RGMII_TX_EN(gmac->id);
167 		break;
168 
169 	case PHY_INTERFACE_MODE_SGMII:
170 		div = get_clk_div_sgmii(gmac, speed);
171 		clk_bits = NSS_COMMON_CLK_GATE_GMII_RX_EN(gmac->id) |
172 			   NSS_COMMON_CLK_GATE_GMII_TX_EN(gmac->id);
173 		break;
174 
175 	default:
176 		dev_err(&gmac->pdev->dev, "Unsupported PHY mode: \"%s\"\n",
177 			phy_modes(gmac->phy_mode));
178 		return -EINVAL;
179 	}
180 
181 	/* Disable the clocks */
182 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_GATE, &val);
183 	val &= ~clk_bits;
184 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_GATE, val);
185 
186 	/* Set the divider */
187 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_DIV0, &val);
188 	val &= ~(NSS_COMMON_CLK_DIV_MASK
189 		 << NSS_COMMON_CLK_DIV_OFFSET(gmac->id));
190 	val |= div << NSS_COMMON_CLK_DIV_OFFSET(gmac->id);
191 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_DIV0, val);
192 
193 	/* Enable the clock back */
194 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_GATE, &val);
195 	val |= clk_bits;
196 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_GATE, val);
197 
198 	return 0;
199 }
200 
201 static int ipq806x_gmac_of_parse(struct ipq806x_gmac *gmac)
202 {
203 	struct device *dev = &gmac->pdev->dev;
204 
205 	gmac->phy_mode = of_get_phy_mode(dev->of_node);
206 	if (gmac->phy_mode < 0) {
207 		dev_err(dev, "missing phy mode property\n");
208 		return -EINVAL;
209 	}
210 
211 	if (of_property_read_u32(dev->of_node, "qcom,id", &gmac->id) < 0) {
212 		dev_err(dev, "missing qcom id property\n");
213 		return -EINVAL;
214 	}
215 
216 	/* The GMACs are called 1 to 4 in the documentation, but to simplify the
217 	 * code and keep it consistent with the Linux convention, we'll number
218 	 * them from 0 to 3 here.
219 	 */
220 	if (gmac->id < 0 || gmac->id > 3) {
221 		dev_err(dev, "invalid gmac id\n");
222 		return -EINVAL;
223 	}
224 
225 	gmac->core_clk = devm_clk_get(dev, "stmmaceth");
226 	if (IS_ERR(gmac->core_clk)) {
227 		dev_err(dev, "missing stmmaceth clk property\n");
228 		return PTR_ERR(gmac->core_clk);
229 	}
230 	clk_set_rate(gmac->core_clk, 266000000);
231 
232 	/* Setup the register map for the nss common registers */
233 	gmac->nss_common = syscon_regmap_lookup_by_phandle(dev->of_node,
234 							   "qcom,nss-common");
235 	if (IS_ERR(gmac->nss_common)) {
236 		dev_err(dev, "missing nss-common node\n");
237 		return PTR_ERR(gmac->nss_common);
238 	}
239 
240 	/* Setup the register map for the qsgmii csr registers */
241 	gmac->qsgmii_csr = syscon_regmap_lookup_by_phandle(dev->of_node,
242 							   "qcom,qsgmii-csr");
243 	if (IS_ERR(gmac->qsgmii_csr))
244 		dev_err(dev, "missing qsgmii-csr node\n");
245 
246 	return PTR_ERR_OR_ZERO(gmac->qsgmii_csr);
247 }
248 
249 static void ipq806x_gmac_fix_mac_speed(void *priv, unsigned int speed)
250 {
251 	struct ipq806x_gmac *gmac = priv;
252 
253 	ipq806x_gmac_set_speed(gmac, speed);
254 }
255 
256 static int ipq806x_gmac_probe(struct platform_device *pdev)
257 {
258 	struct plat_stmmacenet_data *plat_dat;
259 	struct stmmac_resources stmmac_res;
260 	struct device *dev = &pdev->dev;
261 	struct ipq806x_gmac *gmac;
262 	int val;
263 	int err;
264 
265 	val = stmmac_get_platform_resources(pdev, &stmmac_res);
266 	if (val)
267 		return val;
268 
269 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
270 	if (IS_ERR(plat_dat))
271 		return PTR_ERR(plat_dat);
272 
273 	gmac = devm_kzalloc(dev, sizeof(*gmac), GFP_KERNEL);
274 	if (!gmac) {
275 		err = -ENOMEM;
276 		goto err_remove_config_dt;
277 	}
278 
279 	gmac->pdev = pdev;
280 
281 	err = ipq806x_gmac_of_parse(gmac);
282 	if (err) {
283 		dev_err(dev, "device tree parsing error\n");
284 		goto err_remove_config_dt;
285 	}
286 
287 	regmap_write(gmac->qsgmii_csr, QSGMII_PCS_CAL_LCKDT_CTL,
288 		     QSGMII_PCS_CAL_LCKDT_CTL_RST);
289 
290 	/* Inter frame gap is set to 12 */
291 	val = 12 << NSS_COMMON_GMAC_CTL_IFG_OFFSET |
292 	      12 << NSS_COMMON_GMAC_CTL_IFG_LIMIT_OFFSET;
293 	/* We also initiate an AXI low power exit request */
294 	val |= NSS_COMMON_GMAC_CTL_CSYS_REQ;
295 	switch (gmac->phy_mode) {
296 	case PHY_INTERFACE_MODE_RGMII:
297 		val |= NSS_COMMON_GMAC_CTL_PHY_IFACE_SEL;
298 		break;
299 	case PHY_INTERFACE_MODE_SGMII:
300 		val &= ~NSS_COMMON_GMAC_CTL_PHY_IFACE_SEL;
301 		break;
302 	default:
303 		dev_err(&pdev->dev, "Unsupported PHY mode: \"%s\"\n",
304 			phy_modes(gmac->phy_mode));
305 		err = -EINVAL;
306 		goto err_remove_config_dt;
307 	}
308 	regmap_write(gmac->nss_common, NSS_COMMON_GMAC_CTL(gmac->id), val);
309 
310 	/* Configure the clock src according to the mode */
311 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_SRC_CTRL, &val);
312 	val &= ~(1 << NSS_COMMON_CLK_SRC_CTRL_OFFSET(gmac->id));
313 	switch (gmac->phy_mode) {
314 	case PHY_INTERFACE_MODE_RGMII:
315 		val |= NSS_COMMON_CLK_SRC_CTRL_RGMII(gmac->id) <<
316 			NSS_COMMON_CLK_SRC_CTRL_OFFSET(gmac->id);
317 		break;
318 	case PHY_INTERFACE_MODE_SGMII:
319 		val |= NSS_COMMON_CLK_SRC_CTRL_SGMII(gmac->id) <<
320 			NSS_COMMON_CLK_SRC_CTRL_OFFSET(gmac->id);
321 		break;
322 	default:
323 		dev_err(&pdev->dev, "Unsupported PHY mode: \"%s\"\n",
324 			phy_modes(gmac->phy_mode));
325 		err = -EINVAL;
326 		goto err_remove_config_dt;
327 	}
328 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_SRC_CTRL, val);
329 
330 	/* Enable PTP clock */
331 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_GATE, &val);
332 	val |= NSS_COMMON_CLK_GATE_PTP_EN(gmac->id);
333 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_GATE, val);
334 
335 	if (gmac->phy_mode == PHY_INTERFACE_MODE_SGMII) {
336 		regmap_write(gmac->qsgmii_csr, QSGMII_PHY_SGMII_CTL(gmac->id),
337 			     QSGMII_PHY_CDR_EN |
338 			     QSGMII_PHY_RX_FRONT_EN |
339 			     QSGMII_PHY_RX_SIGNAL_DETECT_EN |
340 			     QSGMII_PHY_TX_DRIVER_EN |
341 			     QSGMII_PHY_QSGMII_EN |
342 			     0x4ul << QSGMII_PHY_PHASE_LOOP_GAIN_OFFSET |
343 			     0x3ul << QSGMII_PHY_RX_DC_BIAS_OFFSET |
344 			     0x1ul << QSGMII_PHY_RX_INPUT_EQU_OFFSET |
345 			     0x2ul << QSGMII_PHY_CDR_PI_SLEW_OFFSET |
346 			     0xCul << QSGMII_PHY_TX_DRV_AMP_OFFSET);
347 	}
348 
349 	plat_dat->has_gmac = true;
350 	plat_dat->bsp_priv = gmac;
351 	plat_dat->fix_mac_speed = ipq806x_gmac_fix_mac_speed;
352 
353 	err = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
354 	if (err)
355 		goto err_remove_config_dt;
356 
357 	return 0;
358 
359 err_remove_config_dt:
360 	stmmac_remove_config_dt(pdev, plat_dat);
361 
362 	return err;
363 }
364 
365 static const struct of_device_id ipq806x_gmac_dwmac_match[] = {
366 	{ .compatible = "qcom,ipq806x-gmac" },
367 	{ }
368 };
369 MODULE_DEVICE_TABLE(of, ipq806x_gmac_dwmac_match);
370 
371 static struct platform_driver ipq806x_gmac_dwmac_driver = {
372 	.probe = ipq806x_gmac_probe,
373 	.remove = stmmac_pltfr_remove,
374 	.driver = {
375 		.name		= "ipq806x-gmac-dwmac",
376 		.pm		= &stmmac_pltfr_pm_ops,
377 		.of_match_table	= ipq806x_gmac_dwmac_match,
378 	},
379 };
380 module_platform_driver(ipq806x_gmac_dwmac_driver);
381 
382 MODULE_AUTHOR("Mathieu Olivari <mathieu@codeaurora.org>");
383 MODULE_DESCRIPTION("Qualcomm Atheros IPQ806x DWMAC specific glue layer");
384 MODULE_LICENSE("Dual BSD/GPL");
385