1 /***********************license start***************
2  * Author: Cavium Networks
3  *
4  * Contact: support@caviumnetworks.com
5  * This file is part of the OCTEON SDK
6  *
7  * Copyright (c) 2003-2008 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  ***********************license end**************************************/
27 
28 /*
29  * Small helper utilities.
30  */
31 #include <linux/kernel.h>
32 
33 #include <asm/octeon/octeon.h>
34 
35 #include <asm/octeon/cvmx-config.h>
36 
37 #include <asm/octeon/cvmx-fpa.h>
38 #include <asm/octeon/cvmx-pip.h>
39 #include <asm/octeon/cvmx-pko.h>
40 #include <asm/octeon/cvmx-ipd.h>
41 #include <asm/octeon/cvmx-spi.h>
42 
43 #include <asm/octeon/cvmx-helper.h>
44 #include <asm/octeon/cvmx-helper-util.h>
45 
46 #include <asm/octeon/cvmx-ipd-defs.h>
47 
48 /**
49  * Convert a interface mode into a human readable string
50  *
51  * @mode:   Mode to convert
52  *
53  * Returns String
54  */
55 const char *cvmx_helper_interface_mode_to_string(cvmx_helper_interface_mode_t
56 						 mode)
57 {
58 	switch (mode) {
59 	case CVMX_HELPER_INTERFACE_MODE_DISABLED:
60 		return "DISABLED";
61 	case CVMX_HELPER_INTERFACE_MODE_RGMII:
62 		return "RGMII";
63 	case CVMX_HELPER_INTERFACE_MODE_GMII:
64 		return "GMII";
65 	case CVMX_HELPER_INTERFACE_MODE_SPI:
66 		return "SPI";
67 	case CVMX_HELPER_INTERFACE_MODE_PCIE:
68 		return "PCIE";
69 	case CVMX_HELPER_INTERFACE_MODE_XAUI:
70 		return "XAUI";
71 	case CVMX_HELPER_INTERFACE_MODE_SGMII:
72 		return "SGMII";
73 	case CVMX_HELPER_INTERFACE_MODE_PICMG:
74 		return "PICMG";
75 	case CVMX_HELPER_INTERFACE_MODE_NPI:
76 		return "NPI";
77 	case CVMX_HELPER_INTERFACE_MODE_LOOP:
78 		return "LOOP";
79 	}
80 	return "UNKNOWN";
81 }
82 
83 /**
84  * Setup Random Early Drop on a specific input queue
85  *
86  * @queue:  Input queue to setup RED on (0-7)
87  * @pass_thresh:
88  *		 Packets will begin slowly dropping when there are less than
89  *		 this many packet buffers free in FPA 0.
90  * @drop_thresh:
91  *		 All incoming packets will be dropped when there are less
92  *		 than this many free packet buffers in FPA 0.
93  * Returns Zero on success. Negative on failure
94  */
95 static int cvmx_helper_setup_red_queue(int queue, int pass_thresh,
96 				       int drop_thresh)
97 {
98 	union cvmx_ipd_qosx_red_marks red_marks;
99 	union cvmx_ipd_red_quex_param red_param;
100 
101 	/* Set RED to begin dropping packets when there are pass_thresh buffers
102 	   left. It will linearly drop more packets until reaching drop_thresh
103 	   buffers */
104 	red_marks.u64 = 0;
105 	red_marks.s.drop = drop_thresh;
106 	red_marks.s.pass = pass_thresh;
107 	cvmx_write_csr(CVMX_IPD_QOSX_RED_MARKS(queue), red_marks.u64);
108 
109 	/* Use the actual queue 0 counter, not the average */
110 	red_param.u64 = 0;
111 	red_param.s.prb_con =
112 	    (255ul << 24) / (red_marks.s.pass - red_marks.s.drop);
113 	red_param.s.avg_con = 1;
114 	red_param.s.new_con = 255;
115 	red_param.s.use_pcnt = 1;
116 	cvmx_write_csr(CVMX_IPD_RED_QUEX_PARAM(queue), red_param.u64);
117 	return 0;
118 }
119 
120 /**
121  * Setup Random Early Drop to automatically begin dropping packets.
122  *
123  * @pass_thresh:
124  *		 Packets will begin slowly dropping when there are less than
125  *		 this many packet buffers free in FPA 0.
126  * @drop_thresh:
127  *		 All incoming packets will be dropped when there are less
128  *		 than this many free packet buffers in FPA 0.
129  * Returns Zero on success. Negative on failure
130  */
131 int cvmx_helper_setup_red(int pass_thresh, int drop_thresh)
132 {
133 	union cvmx_ipd_portx_bp_page_cnt page_cnt;
134 	union cvmx_ipd_bp_prt_red_end ipd_bp_prt_red_end;
135 	union cvmx_ipd_red_port_enable red_port_enable;
136 	int queue;
137 	int interface;
138 	int port;
139 
140 	/* Disable backpressure based on queued buffers. It needs SW support */
141 	page_cnt.u64 = 0;
142 	page_cnt.s.bp_enb = 0;
143 	page_cnt.s.page_cnt = 100;
144 	for (interface = 0; interface < 2; interface++) {
145 		for (port = cvmx_helper_get_first_ipd_port(interface);
146 		     port < cvmx_helper_get_last_ipd_port(interface); port++)
147 			cvmx_write_csr(CVMX_IPD_PORTX_BP_PAGE_CNT(port),
148 				       page_cnt.u64);
149 	}
150 
151 	for (queue = 0; queue < 8; queue++)
152 		cvmx_helper_setup_red_queue(queue, pass_thresh, drop_thresh);
153 
154 	/* Shutoff the dropping based on the per port page count. SW isn't
155 	   decrementing it right now */
156 	ipd_bp_prt_red_end.u64 = 0;
157 	ipd_bp_prt_red_end.s.prt_enb = 0;
158 	cvmx_write_csr(CVMX_IPD_BP_PRT_RED_END, ipd_bp_prt_red_end.u64);
159 
160 	red_port_enable.u64 = 0;
161 	red_port_enable.s.prt_enb = 0xfffffffffull;
162 	red_port_enable.s.avg_dly = 10000;
163 	red_port_enable.s.prb_dly = 10000;
164 	cvmx_write_csr(CVMX_IPD_RED_PORT_ENABLE, red_port_enable.u64);
165 
166 	return 0;
167 }
168 EXPORT_SYMBOL_GPL(cvmx_helper_setup_red);
169 
170 /**
171  * Setup the common GMX settings that determine the number of
172  * ports. These setting apply to almost all configurations of all
173  * chips.
174  *
175  * @interface: Interface to configure
176  * @num_ports: Number of ports on the interface
177  *
178  * Returns Zero on success, negative on failure
179  */
180 int __cvmx_helper_setup_gmx(int interface, int num_ports)
181 {
182 	union cvmx_gmxx_tx_prts gmx_tx_prts;
183 	union cvmx_gmxx_rx_prts gmx_rx_prts;
184 	union cvmx_pko_reg_gmx_port_mode pko_mode;
185 	union cvmx_gmxx_txx_thresh gmx_tx_thresh;
186 	int index;
187 
188 	/* Tell GMX the number of TX ports on this interface */
189 	gmx_tx_prts.u64 = cvmx_read_csr(CVMX_GMXX_TX_PRTS(interface));
190 	gmx_tx_prts.s.prts = num_ports;
191 	cvmx_write_csr(CVMX_GMXX_TX_PRTS(interface), gmx_tx_prts.u64);
192 
193 	/* Tell GMX the number of RX ports on this interface.  This only
194 	 ** applies to *GMII and XAUI ports */
195 	if (cvmx_helper_interface_get_mode(interface) ==
196 	    CVMX_HELPER_INTERFACE_MODE_RGMII
197 	    || cvmx_helper_interface_get_mode(interface) ==
198 	    CVMX_HELPER_INTERFACE_MODE_SGMII
199 	    || cvmx_helper_interface_get_mode(interface) ==
200 	    CVMX_HELPER_INTERFACE_MODE_GMII
201 	    || cvmx_helper_interface_get_mode(interface) ==
202 	    CVMX_HELPER_INTERFACE_MODE_XAUI) {
203 		if (num_ports > 4) {
204 			cvmx_dprintf("__cvmx_helper_setup_gmx: Illegal "
205 				     "num_ports\n");
206 			return -1;
207 		}
208 
209 		gmx_rx_prts.u64 = cvmx_read_csr(CVMX_GMXX_RX_PRTS(interface));
210 		gmx_rx_prts.s.prts = num_ports;
211 		cvmx_write_csr(CVMX_GMXX_RX_PRTS(interface), gmx_rx_prts.u64);
212 	}
213 
214 	/* Skip setting CVMX_PKO_REG_GMX_PORT_MODE on 30XX, 31XX, and 50XX */
215 	if (!OCTEON_IS_MODEL(OCTEON_CN30XX) && !OCTEON_IS_MODEL(OCTEON_CN31XX)
216 	    && !OCTEON_IS_MODEL(OCTEON_CN50XX)) {
217 		/* Tell PKO the number of ports on this interface */
218 		pko_mode.u64 = cvmx_read_csr(CVMX_PKO_REG_GMX_PORT_MODE);
219 		if (interface == 0) {
220 			if (num_ports == 1)
221 				pko_mode.s.mode0 = 4;
222 			else if (num_ports == 2)
223 				pko_mode.s.mode0 = 3;
224 			else if (num_ports <= 4)
225 				pko_mode.s.mode0 = 2;
226 			else if (num_ports <= 8)
227 				pko_mode.s.mode0 = 1;
228 			else
229 				pko_mode.s.mode0 = 0;
230 		} else {
231 			if (num_ports == 1)
232 				pko_mode.s.mode1 = 4;
233 			else if (num_ports == 2)
234 				pko_mode.s.mode1 = 3;
235 			else if (num_ports <= 4)
236 				pko_mode.s.mode1 = 2;
237 			else if (num_ports <= 8)
238 				pko_mode.s.mode1 = 1;
239 			else
240 				pko_mode.s.mode1 = 0;
241 		}
242 		cvmx_write_csr(CVMX_PKO_REG_GMX_PORT_MODE, pko_mode.u64);
243 	}
244 
245 	/*
246 	 * Set GMX to buffer as much data as possible before starting
247 	 * transmit.  This reduces the chances that we have a TX under
248 	 * run due to memory contention. Any packet that fits entirely
249 	 * in the GMX FIFO can never have an under run regardless of
250 	 * memory load.
251 	 */
252 	gmx_tx_thresh.u64 = cvmx_read_csr(CVMX_GMXX_TXX_THRESH(0, interface));
253 	if (OCTEON_IS_MODEL(OCTEON_CN30XX) || OCTEON_IS_MODEL(OCTEON_CN31XX)
254 	    || OCTEON_IS_MODEL(OCTEON_CN50XX)) {
255 		/* These chips have a fixed max threshold of 0x40 */
256 		gmx_tx_thresh.s.cnt = 0x40;
257 	} else {
258 		/* Choose the max value for the number of ports */
259 		if (num_ports <= 1)
260 			gmx_tx_thresh.s.cnt = 0x100 / 1;
261 		else if (num_ports == 2)
262 			gmx_tx_thresh.s.cnt = 0x100 / 2;
263 		else
264 			gmx_tx_thresh.s.cnt = 0x100 / 4;
265 	}
266 	/*
267 	 * SPI and XAUI can have lots of ports but the GMX hardware
268 	 * only ever has a max of 4.
269 	 */
270 	if (num_ports > 4)
271 		num_ports = 4;
272 	for (index = 0; index < num_ports; index++)
273 		cvmx_write_csr(CVMX_GMXX_TXX_THRESH(index, interface),
274 			       gmx_tx_thresh.u64);
275 
276 	return 0;
277 }
278 
279 /**
280  * Returns the IPD/PKO port number for a port on the given
281  * interface.
282  *
283  * @interface: Interface to use
284  * @port:      Port on the interface
285  *
286  * Returns IPD/PKO port number
287  */
288 int cvmx_helper_get_ipd_port(int interface, int port)
289 {
290 	switch (interface) {
291 	case 0:
292 		return port;
293 	case 1:
294 		return port + 16;
295 	case 2:
296 		return port + 32;
297 	case 3:
298 		return port + 36;
299 	case 4:
300 		return port + 40;
301 	case 5:
302 		return port + 44;
303 	}
304 	return -1;
305 }
306 EXPORT_SYMBOL_GPL(cvmx_helper_get_ipd_port);
307 
308 /**
309  * Returns the interface number for an IPD/PKO port number.
310  *
311  * @ipd_port: IPD/PKO port number
312  *
313  * Returns Interface number
314  */
315 int cvmx_helper_get_interface_num(int ipd_port)
316 {
317 	if (ipd_port < 16)
318 		return 0;
319 	else if (ipd_port < 32)
320 		return 1;
321 	else if (ipd_port < 36)
322 		return 2;
323 	else if (ipd_port < 40)
324 		return 3;
325 	else if (ipd_port < 44)
326 		return 4;
327 	else if (ipd_port < 48)
328 		return 5;
329 	else
330 		cvmx_dprintf("cvmx_helper_get_interface_num: Illegal IPD "
331 			     "port number\n");
332 
333 	return -1;
334 }
335 EXPORT_SYMBOL_GPL(cvmx_helper_get_interface_num);
336 
337 /**
338  * Returns the interface index number for an IPD/PKO port
339  * number.
340  *
341  * @ipd_port: IPD/PKO port number
342  *
343  * Returns Interface index number
344  */
345 int cvmx_helper_get_interface_index_num(int ipd_port)
346 {
347 	if (ipd_port < 32)
348 		return ipd_port & 15;
349 	else if (ipd_port < 36)
350 		return ipd_port & 3;
351 	else if (ipd_port < 40)
352 		return ipd_port & 3;
353 	else if (ipd_port < 44)
354 		return ipd_port & 3;
355 	else if (ipd_port < 48)
356 		return ipd_port & 3;
357 	else
358 		cvmx_dprintf("cvmx_helper_get_interface_index_num: "
359 			     "Illegal IPD port number\n");
360 
361 	return -1;
362 }
363 EXPORT_SYMBOL_GPL(cvmx_helper_get_interface_index_num);
364