1 /*********************************************************************
2  * Author: Cavium Networks
3  *
4  * Contact: support@caviumnetworks.com
5  * This file is part of the OCTEON SDK
6  *
7  * Copyright (c) 2003-2007 Cavium Networks
8  *
9  * This file is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License, Version 2, as
11  * published by the Free Software Foundation.
12  *
13  * This file is distributed in the hope that it will be useful, but
14  * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
16  * NONINFRINGEMENT.  See the GNU General Public License for more
17  * details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this file; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22  * or visit http://www.gnu.org/licenses/.
23  *
24  * This file may also be available under a different license from Cavium.
25  * Contact Cavium Networks for more information
26 **********************************************************************/
27 #include <linux/kernel.h>
28 #include <linux/netdevice.h>
29 #include <linux/interrupt.h>
30 #include <linux/phy.h>
31 #include <linux/ratelimit.h>
32 #include <net/dst.h>
33 
34 #include <asm/octeon/octeon.h>
35 
36 #include "ethernet-defines.h"
37 #include "octeon-ethernet.h"
38 #include "ethernet-util.h"
39 
40 #include <asm/octeon/cvmx-helper.h>
41 
42 #include <asm/octeon/cvmx-ipd-defs.h>
43 #include <asm/octeon/cvmx-npi-defs.h>
44 #include <asm/octeon/cvmx-gmxx-defs.h>
45 
46 static DEFINE_SPINLOCK(global_register_lock);
47 
48 static int number_rgmii_ports;
49 
50 static void cvm_oct_rgmii_poll(struct net_device *dev)
51 {
52 	struct octeon_ethernet *priv = netdev_priv(dev);
53 	unsigned long flags = 0;
54 	cvmx_helper_link_info_t link_info;
55 	int use_global_register_lock = (priv->phydev == NULL);
56 
57 	BUG_ON(in_interrupt());
58 	if (use_global_register_lock) {
59 		/*
60 		 * Take the global register lock since we are going to
61 		 * touch registers that affect more than one port.
62 		 */
63 		spin_lock_irqsave(&global_register_lock, flags);
64 	} else {
65 		mutex_lock(&priv->phydev->bus->mdio_lock);
66 	}
67 
68 	link_info = cvmx_helper_link_get(priv->port);
69 	if (link_info.u64 == priv->link_info) {
70 
71 		/*
72 		 * If the 10Mbps preamble workaround is supported and we're
73 		 * at 10Mbps we may need to do some special checking.
74 		 */
75 		if (USE_10MBPS_PREAMBLE_WORKAROUND && (link_info.s.speed == 10)) {
76 
77 			/*
78 			 * Read the GMXX_RXX_INT_REG[PCTERR] bit and
79 			 * see if we are getting preamble errors.
80 			 */
81 			int interface = INTERFACE(priv->port);
82 			int index = INDEX(priv->port);
83 			union cvmx_gmxx_rxx_int_reg gmxx_rxx_int_reg;
84 			gmxx_rxx_int_reg.u64 =
85 			    cvmx_read_csr(CVMX_GMXX_RXX_INT_REG
86 					  (index, interface));
87 			if (gmxx_rxx_int_reg.s.pcterr) {
88 
89 				/*
90 				 * We are getting preamble errors at
91 				 * 10Mbps.  Most likely the PHY is
92 				 * giving us packets with mis aligned
93 				 * preambles. In order to get these
94 				 * packets we need to disable preamble
95 				 * checking and do it in software.
96 				 */
97 				union cvmx_gmxx_rxx_frm_ctl gmxx_rxx_frm_ctl;
98 				union cvmx_ipd_sub_port_fcs ipd_sub_port_fcs;
99 
100 				/* Disable preamble checking */
101 				gmxx_rxx_frm_ctl.u64 =
102 				    cvmx_read_csr(CVMX_GMXX_RXX_FRM_CTL
103 						  (index, interface));
104 				gmxx_rxx_frm_ctl.s.pre_chk = 0;
105 				cvmx_write_csr(CVMX_GMXX_RXX_FRM_CTL
106 					       (index, interface),
107 					       gmxx_rxx_frm_ctl.u64);
108 
109 				/* Disable FCS stripping */
110 				ipd_sub_port_fcs.u64 =
111 				    cvmx_read_csr(CVMX_IPD_SUB_PORT_FCS);
112 				ipd_sub_port_fcs.s.port_bit &=
113 				    0xffffffffull ^ (1ull << priv->port);
114 				cvmx_write_csr(CVMX_IPD_SUB_PORT_FCS,
115 					       ipd_sub_port_fcs.u64);
116 
117 				/* Clear any error bits */
118 				cvmx_write_csr(CVMX_GMXX_RXX_INT_REG
119 					       (index, interface),
120 					       gmxx_rxx_int_reg.u64);
121 				printk_ratelimited("%s: Using 10Mbps with software "
122 						   "preamble removal\n",
123 						   dev->name);
124 			}
125 		}
126 
127 		if (use_global_register_lock)
128 			spin_unlock_irqrestore(&global_register_lock, flags);
129 		else
130 			mutex_unlock(&priv->phydev->bus->mdio_lock);
131 		return;
132 	}
133 
134 	/* If the 10Mbps preamble workaround is allowed we need to on
135 	   preamble checking, FCS stripping, and clear error bits on
136 	   every speed change. If errors occur during 10Mbps operation
137 	   the above code will change this stuff */
138 	if (USE_10MBPS_PREAMBLE_WORKAROUND) {
139 
140 		union cvmx_gmxx_rxx_frm_ctl gmxx_rxx_frm_ctl;
141 		union cvmx_ipd_sub_port_fcs ipd_sub_port_fcs;
142 		union cvmx_gmxx_rxx_int_reg gmxx_rxx_int_reg;
143 		int interface = INTERFACE(priv->port);
144 		int index = INDEX(priv->port);
145 
146 		/* Enable preamble checking */
147 		gmxx_rxx_frm_ctl.u64 =
148 		    cvmx_read_csr(CVMX_GMXX_RXX_FRM_CTL(index, interface));
149 		gmxx_rxx_frm_ctl.s.pre_chk = 1;
150 		cvmx_write_csr(CVMX_GMXX_RXX_FRM_CTL(index, interface),
151 			       gmxx_rxx_frm_ctl.u64);
152 		/* Enable FCS stripping */
153 		ipd_sub_port_fcs.u64 = cvmx_read_csr(CVMX_IPD_SUB_PORT_FCS);
154 		ipd_sub_port_fcs.s.port_bit |= 1ull << priv->port;
155 		cvmx_write_csr(CVMX_IPD_SUB_PORT_FCS, ipd_sub_port_fcs.u64);
156 		/* Clear any error bits */
157 		gmxx_rxx_int_reg.u64 =
158 		    cvmx_read_csr(CVMX_GMXX_RXX_INT_REG(index, interface));
159 		cvmx_write_csr(CVMX_GMXX_RXX_INT_REG(index, interface),
160 			       gmxx_rxx_int_reg.u64);
161 	}
162 	if (priv->phydev == NULL) {
163 		link_info = cvmx_helper_link_autoconf(priv->port);
164 		priv->link_info = link_info.u64;
165 	}
166 
167 	if (use_global_register_lock)
168 		spin_unlock_irqrestore(&global_register_lock, flags);
169 	else
170 		mutex_unlock(&priv->phydev->bus->mdio_lock);
171 
172 	if (priv->phydev == NULL) {
173 		/* Tell core. */
174 		if (link_info.s.link_up) {
175 			if (!netif_carrier_ok(dev))
176 				netif_carrier_on(dev);
177 			if (priv->queue != -1)
178 				printk_ratelimited("%s: %u Mbps %s duplex, "
179 						   "port %2d, queue %2d\n",
180 						   dev->name, link_info.s.speed,
181 						   (link_info.s.full_duplex) ?
182 						   "Full" : "Half",
183 						   priv->port, priv->queue);
184 			else
185 				printk_ratelimited("%s: %u Mbps %s duplex, "
186 						   "port %2d, POW\n",
187 						   dev->name, link_info.s.speed,
188 						   (link_info.s.full_duplex) ?
189 						   "Full" : "Half",
190 						   priv->port);
191 		} else {
192 			if (netif_carrier_ok(dev))
193 				netif_carrier_off(dev);
194 			printk_ratelimited("%s: Link down\n", dev->name);
195 		}
196 	}
197 }
198 
199 static irqreturn_t cvm_oct_rgmii_rml_interrupt(int cpl, void *dev_id)
200 {
201 	union cvmx_npi_rsl_int_blocks rsl_int_blocks;
202 	int index;
203 	irqreturn_t return_status = IRQ_NONE;
204 
205 	rsl_int_blocks.u64 = cvmx_read_csr(CVMX_NPI_RSL_INT_BLOCKS);
206 
207 	/* Check and see if this interrupt was caused by the GMX0 block */
208 	if (rsl_int_blocks.s.gmx0) {
209 
210 		int interface = 0;
211 		/* Loop through every port of this interface */
212 		for (index = 0;
213 		     index < cvmx_helper_ports_on_interface(interface);
214 		     index++) {
215 
216 			/* Read the GMX interrupt status bits */
217 			union cvmx_gmxx_rxx_int_reg gmx_rx_int_reg;
218 			gmx_rx_int_reg.u64 =
219 			    cvmx_read_csr(CVMX_GMXX_RXX_INT_REG
220 					  (index, interface));
221 			gmx_rx_int_reg.u64 &=
222 			    cvmx_read_csr(CVMX_GMXX_RXX_INT_EN
223 					  (index, interface));
224 			/* Poll the port if inband status changed */
225 			if (gmx_rx_int_reg.s.phy_dupx
226 			    || gmx_rx_int_reg.s.phy_link
227 			    || gmx_rx_int_reg.s.phy_spd) {
228 
229 				struct net_device *dev =
230 				    cvm_oct_device[cvmx_helper_get_ipd_port
231 						   (interface, index)];
232 				struct octeon_ethernet *priv = netdev_priv(dev);
233 
234 				if (dev && !atomic_read(&cvm_oct_poll_queue_stopping))
235 					queue_work(cvm_oct_poll_queue, &priv->port_work);
236 
237 				gmx_rx_int_reg.u64 = 0;
238 				gmx_rx_int_reg.s.phy_dupx = 1;
239 				gmx_rx_int_reg.s.phy_link = 1;
240 				gmx_rx_int_reg.s.phy_spd = 1;
241 				cvmx_write_csr(CVMX_GMXX_RXX_INT_REG
242 					       (index, interface),
243 					       gmx_rx_int_reg.u64);
244 				return_status = IRQ_HANDLED;
245 			}
246 		}
247 	}
248 
249 	/* Check and see if this interrupt was caused by the GMX1 block */
250 	if (rsl_int_blocks.s.gmx1) {
251 
252 		int interface = 1;
253 		/* Loop through every port of this interface */
254 		for (index = 0;
255 		     index < cvmx_helper_ports_on_interface(interface);
256 		     index++) {
257 
258 			/* Read the GMX interrupt status bits */
259 			union cvmx_gmxx_rxx_int_reg gmx_rx_int_reg;
260 			gmx_rx_int_reg.u64 =
261 			    cvmx_read_csr(CVMX_GMXX_RXX_INT_REG
262 					  (index, interface));
263 			gmx_rx_int_reg.u64 &=
264 			    cvmx_read_csr(CVMX_GMXX_RXX_INT_EN
265 					  (index, interface));
266 			/* Poll the port if inband status changed */
267 			if (gmx_rx_int_reg.s.phy_dupx
268 			    || gmx_rx_int_reg.s.phy_link
269 			    || gmx_rx_int_reg.s.phy_spd) {
270 
271 				struct net_device *dev =
272 				    cvm_oct_device[cvmx_helper_get_ipd_port
273 						   (interface, index)];
274 				struct octeon_ethernet *priv = netdev_priv(dev);
275 
276 				if (dev && !atomic_read(&cvm_oct_poll_queue_stopping))
277 					queue_work(cvm_oct_poll_queue, &priv->port_work);
278 
279 				gmx_rx_int_reg.u64 = 0;
280 				gmx_rx_int_reg.s.phy_dupx = 1;
281 				gmx_rx_int_reg.s.phy_link = 1;
282 				gmx_rx_int_reg.s.phy_spd = 1;
283 				cvmx_write_csr(CVMX_GMXX_RXX_INT_REG
284 					       (index, interface),
285 					       gmx_rx_int_reg.u64);
286 				return_status = IRQ_HANDLED;
287 			}
288 		}
289 	}
290 	return return_status;
291 }
292 
293 int cvm_oct_rgmii_open(struct net_device *dev)
294 {
295 	union cvmx_gmxx_prtx_cfg gmx_cfg;
296 	struct octeon_ethernet *priv = netdev_priv(dev);
297 	int interface = INTERFACE(priv->port);
298 	int index = INDEX(priv->port);
299 	cvmx_helper_link_info_t link_info;
300 
301 	gmx_cfg.u64 = cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
302 	gmx_cfg.s.en = 1;
303 	cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64);
304 
305 	if (!octeon_is_simulation()) {
306 		link_info = cvmx_helper_link_get(priv->port);
307 		if (!link_info.s.link_up)
308 			netif_carrier_off(dev);
309 	}
310 
311 	return 0;
312 }
313 
314 int cvm_oct_rgmii_stop(struct net_device *dev)
315 {
316 	union cvmx_gmxx_prtx_cfg gmx_cfg;
317 	struct octeon_ethernet *priv = netdev_priv(dev);
318 	int interface = INTERFACE(priv->port);
319 	int index = INDEX(priv->port);
320 
321 	gmx_cfg.u64 = cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
322 	gmx_cfg.s.en = 0;
323 	cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64);
324 	return 0;
325 }
326 
327 static void cvm_oct_rgmii_immediate_poll(struct work_struct *work)
328 {
329 	struct octeon_ethernet *priv = container_of(work, struct octeon_ethernet, port_work);
330 	cvm_oct_rgmii_poll(cvm_oct_device[priv->port]);
331 }
332 
333 int cvm_oct_rgmii_init(struct net_device *dev)
334 {
335 	struct octeon_ethernet *priv = netdev_priv(dev);
336 	int r;
337 
338 	cvm_oct_common_init(dev);
339 	dev->netdev_ops->ndo_stop(dev);
340 	INIT_WORK(&priv->port_work, cvm_oct_rgmii_immediate_poll);
341 	/*
342 	 * Due to GMX errata in CN3XXX series chips, it is necessary
343 	 * to take the link down immediately when the PHY changes
344 	 * state. In order to do this we call the poll function every
345 	 * time the RGMII inband status changes.  This may cause
346 	 * problems if the PHY doesn't implement inband status
347 	 * properly.
348 	 */
349 	if (number_rgmii_ports == 0) {
350 		r = request_irq(OCTEON_IRQ_RML, cvm_oct_rgmii_rml_interrupt,
351 				IRQF_SHARED, "RGMII", &number_rgmii_ports);
352 		if (r != 0)
353 			return r;
354 	}
355 	number_rgmii_ports++;
356 
357 	/*
358 	 * Only true RGMII ports need to be polled. In GMII mode, port
359 	 * 0 is really a RGMII port.
360 	 */
361 	if (((priv->imode == CVMX_HELPER_INTERFACE_MODE_GMII)
362 	     && (priv->port == 0))
363 	    || (priv->imode == CVMX_HELPER_INTERFACE_MODE_RGMII)) {
364 
365 		if (!octeon_is_simulation()) {
366 
367 			union cvmx_gmxx_rxx_int_en gmx_rx_int_en;
368 			int interface = INTERFACE(priv->port);
369 			int index = INDEX(priv->port);
370 
371 			/*
372 			 * Enable interrupts on inband status changes
373 			 * for this port.
374 			 */
375 			gmx_rx_int_en.u64 = 0;
376 			gmx_rx_int_en.s.phy_dupx = 1;
377 			gmx_rx_int_en.s.phy_link = 1;
378 			gmx_rx_int_en.s.phy_spd = 1;
379 			cvmx_write_csr(CVMX_GMXX_RXX_INT_EN(index, interface),
380 				       gmx_rx_int_en.u64);
381 			priv->poll = cvm_oct_rgmii_poll;
382 		}
383 	}
384 
385 	return 0;
386 }
387 
388 void cvm_oct_rgmii_uninit(struct net_device *dev)
389 {
390 	struct octeon_ethernet *priv = netdev_priv(dev);
391 	cvm_oct_common_uninit(dev);
392 
393 	/*
394 	 * Only true RGMII ports need to be polled. In GMII mode, port
395 	 * 0 is really a RGMII port.
396 	 */
397 	if (((priv->imode == CVMX_HELPER_INTERFACE_MODE_GMII)
398 	     && (priv->port == 0))
399 	    || (priv->imode == CVMX_HELPER_INTERFACE_MODE_RGMII)) {
400 
401 		if (!octeon_is_simulation()) {
402 
403 			union cvmx_gmxx_rxx_int_en gmx_rx_int_en;
404 			int interface = INTERFACE(priv->port);
405 			int index = INDEX(priv->port);
406 
407 			/*
408 			 * Disable interrupts on inband status changes
409 			 * for this port.
410 			 */
411 			gmx_rx_int_en.u64 =
412 			    cvmx_read_csr(CVMX_GMXX_RXX_INT_EN
413 					  (index, interface));
414 			gmx_rx_int_en.s.phy_dupx = 0;
415 			gmx_rx_int_en.s.phy_link = 0;
416 			gmx_rx_int_en.s.phy_spd = 0;
417 			cvmx_write_csr(CVMX_GMXX_RXX_INT_EN(index, interface),
418 				       gmx_rx_int_en.u64);
419 		}
420 	}
421 
422 	/* Remove the interrupt handler when the last port is removed. */
423 	number_rgmii_ports--;
424 	if (number_rgmii_ports == 0)
425 		free_irq(OCTEON_IRQ_RML, &number_rgmii_ports);
426 	cancel_work_sync(&priv->port_work);
427 }
428