]> bbs.cooldavid.org Git - net-next-2.6.git/blame - drivers/net/can/mscan/mpc5xxx_can.c
Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[net-next-2.6.git] / drivers / net / can / mscan / mpc5xxx_can.c
CommitLineData
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1/*
2 * CAN bus driver for the Freescale MPC5xxx embedded CPU.
3 *
4 * Copyright (C) 2004-2005 Andrey Volkov <avolkov@varma-el.com>,
5 * Varma Electronics Oy
6 * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
7 * Copyright (C) 2009 Wolfram Sang, Pengutronix <w.sang@pengutronix.de>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the version 2 of the GNU General Public License
11 * as published by the Free Software Foundation
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/interrupt.h>
26#include <linux/platform_device.h>
27#include <linux/netdevice.h>
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28#include <linux/can/dev.h>
29#include <linux/of_platform.h>
30#include <sysdev/fsl_soc.h>
bf3af547 31#include <linux/clk.h>
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32#include <linux/io.h>
33#include <asm/mpc52xx.h>
34
35#include "mscan.h"
36
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37#define DRV_NAME "mpc5xxx_can"
38
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39struct mpc5xxx_can_data {
40 unsigned int type;
41 u32 (*get_clock)(struct of_device *ofdev, const char *clock_name,
42 int *mscan_clksrc);
43};
44
c5bab5e9 45#ifdef CONFIG_PPC_MPC52xx
bf3af547 46static struct of_device_id __devinitdata mpc52xx_cdm_ids[] = {
afa17a50 47 { .compatible = "fsl,mpc5200-cdm", },
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48 {}
49};
50
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51static u32 __devinit mpc52xx_can_get_clock(struct of_device *ofdev,
52 const char *clock_name,
53 int *mscan_clksrc)
afa17a50 54{
3f158c25 55 unsigned int pvr;
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56 struct mpc52xx_cdm __iomem *cdm;
57 struct device_node *np_cdm;
58 unsigned int freq;
59 u32 val;
60
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61 pvr = mfspr(SPRN_PVR);
62
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63 /*
64 * Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock
65 * (IP_CLK) can be selected as MSCAN clock source. According to
66 * the MPC5200 user's manual, the oscillator clock is the better
67 * choice as it has less jitter. For this reason, it is selected
68 * by default. Unfortunately, it can not be selected for the old
69 * MPC5200 Rev. A chips due to a hardware bug (check errata).
70 */
71 if (clock_name && strcmp(clock_name, "ip") == 0)
72 *mscan_clksrc = MSCAN_CLKSRC_BUS;
73 else
74 *mscan_clksrc = MSCAN_CLKSRC_XTAL;
75
6bd17eb9 76 freq = mpc5xxx_get_bus_frequency(ofdev->dev.of_node);
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77 if (!freq)
78 return 0;
79
bf3af547 80 if (*mscan_clksrc == MSCAN_CLKSRC_BUS || pvr == 0x80822011)
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81 return freq;
82
83 /* Determine SYS_XTAL_IN frequency from the clock domain settings */
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84 np_cdm = of_find_matching_node(NULL, mpc52xx_cdm_ids);
85 if (!np_cdm) {
c5bab5e9 86 dev_err(&ofdev->dev, "can't get clock node!\n");
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87 return 0;
88 }
89 cdm = of_iomap(np_cdm, 0);
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90
91 if (in_8(&cdm->ipb_clk_sel) & 0x1)
92 freq *= 2;
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93 val = in_be32(&cdm->rstcfg);
94
95 freq *= (val & (1 << 5)) ? 8 : 4;
96 freq /= (val & (1 << 6)) ? 12 : 16;
afa17a50 97
bf3af547 98 of_node_put(np_cdm);
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99 iounmap(cdm);
100
101 return freq;
102}
c5bab5e9 103#else /* !CONFIG_PPC_MPC52xx */
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104static u32 __devinit mpc52xx_can_get_clock(struct of_device *ofdev,
105 const char *clock_name,
106 int *mscan_clksrc)
107{
108 return 0;
109}
c5bab5e9 110#endif /* CONFIG_PPC_MPC52xx */
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111
112#ifdef CONFIG_PPC_MPC512x
113struct mpc512x_clockctl {
114 u32 spmr; /* System PLL Mode Reg */
115 u32 sccr[2]; /* System Clk Ctrl Reg 1 & 2 */
116 u32 scfr1; /* System Clk Freq Reg 1 */
117 u32 scfr2; /* System Clk Freq Reg 2 */
118 u32 reserved;
119 u32 bcr; /* Bread Crumb Reg */
120 u32 pccr[12]; /* PSC Clk Ctrl Reg 0-11 */
121 u32 spccr; /* SPDIF Clk Ctrl Reg */
122 u32 cccr; /* CFM Clk Ctrl Reg */
123 u32 dccr; /* DIU Clk Cnfg Reg */
124 u32 mccr[4]; /* MSCAN Clk Ctrl Reg 1-3 */
125};
126
127static struct of_device_id __devinitdata mpc512x_clock_ids[] = {
128 { .compatible = "fsl,mpc5121-clock", },
129 {}
130};
131
132static u32 __devinit mpc512x_can_get_clock(struct of_device *ofdev,
133 const char *clock_name,
134 int *mscan_clksrc)
135{
136 struct mpc512x_clockctl __iomem *clockctl;
137 struct device_node *np_clock;
138 struct clk *sys_clk, *ref_clk;
139 int plen, clockidx, clocksrc = -1;
140 u32 sys_freq, val, clockdiv = 1, freq = 0;
141 const u32 *pval;
142
143 np_clock = of_find_matching_node(NULL, mpc512x_clock_ids);
144 if (!np_clock) {
145 dev_err(&ofdev->dev, "couldn't find clock node\n");
146 return -ENODEV;
147 }
148 clockctl = of_iomap(np_clock, 0);
149 if (!clockctl) {
150 dev_err(&ofdev->dev, "couldn't map clock registers\n");
151 return 0;
152 }
153
154 /* Determine the MSCAN device index from the physical address */
6bd17eb9 155 pval = of_get_property(ofdev->dev.of_node, "reg", &plen);
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156 BUG_ON(!pval || plen < sizeof(*pval));
157 clockidx = (*pval & 0x80) ? 1 : 0;
158 if (*pval & 0x2000)
159 clockidx += 2;
160
161 /*
162 * Clock source and divider selection: 3 different clock sources
163 * can be selected: "ip", "ref" or "sys". For the latter two, a
164 * clock divider can be defined as well. If the clock source is
165 * not specified by the device tree, we first try to find an
166 * optimal CAN source clock based on the system clock. If that
167 * is not posslible, the reference clock will be used.
168 */
169 if (clock_name && !strcmp(clock_name, "ip")) {
170 *mscan_clksrc = MSCAN_CLKSRC_IPS;
6bd17eb9 171 freq = mpc5xxx_get_bus_frequency(ofdev->dev.of_node);
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172 } else {
173 *mscan_clksrc = MSCAN_CLKSRC_BUS;
174
6bd17eb9 175 pval = of_get_property(ofdev->dev.of_node,
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176 "fsl,mscan-clock-divider", &plen);
177 if (pval && plen == sizeof(*pval))
178 clockdiv = *pval;
179 if (!clockdiv)
180 clockdiv = 1;
181
182 if (!clock_name || !strcmp(clock_name, "sys")) {
183 sys_clk = clk_get(&ofdev->dev, "sys_clk");
184 if (!sys_clk) {
185 dev_err(&ofdev->dev, "couldn't get sys_clk\n");
186 goto exit_unmap;
187 }
188 /* Get and round up/down sys clock rate */
189 sys_freq = 1000000 *
190 ((clk_get_rate(sys_clk) + 499999) / 1000000);
191
192 if (!clock_name) {
193 /* A multiple of 16 MHz would be optimal */
194 if ((sys_freq % 16000000) == 0) {
195 clocksrc = 0;
196 clockdiv = sys_freq / 16000000;
197 freq = sys_freq / clockdiv;
198 }
199 } else {
200 clocksrc = 0;
201 freq = sys_freq / clockdiv;
202 }
203 }
204
205 if (clocksrc < 0) {
206 ref_clk = clk_get(&ofdev->dev, "ref_clk");
207 if (!ref_clk) {
208 dev_err(&ofdev->dev, "couldn't get ref_clk\n");
209 goto exit_unmap;
210 }
211 clocksrc = 1;
212 freq = clk_get_rate(ref_clk) / clockdiv;
213 }
214 }
215
216 /* Disable clock */
217 out_be32(&clockctl->mccr[clockidx], 0x0);
218 if (clocksrc >= 0) {
219 /* Set source and divider */
220 val = (clocksrc << 14) | ((clockdiv - 1) << 17);
221 out_be32(&clockctl->mccr[clockidx], val);
222 /* Enable clock */
223 out_be32(&clockctl->mccr[clockidx], val | 0x10000);
224 }
225
226 /* Enable MSCAN clock domain */
227 val = in_be32(&clockctl->sccr[1]);
228 if (!(val & (1 << 25)))
229 out_be32(&clockctl->sccr[1], val | (1 << 25));
230
231 dev_dbg(&ofdev->dev, "using '%s' with frequency divider %d\n",
232 *mscan_clksrc == MSCAN_CLKSRC_IPS ? "ips_clk" :
233 clocksrc == 1 ? "ref_clk" : "sys_clk", clockdiv);
234
235exit_unmap:
236 of_node_put(np_clock);
237 iounmap(clockctl);
238
239 return freq;
240}
241#else /* !CONFIG_PPC_MPC512x */
242static u32 __devinit mpc512x_can_get_clock(struct of_device *ofdev,
243 const char *clock_name,
244 int *mscan_clksrc)
245{
246 return 0;
247}
248#endif /* CONFIG_PPC_MPC512x */
afa17a50 249
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250static int __devinit mpc5xxx_can_probe(struct of_device *ofdev,
251 const struct of_device_id *id)
252{
bf3af547 253 struct mpc5xxx_can_data *data = (struct mpc5xxx_can_data *)id->data;
6bd17eb9 254 struct device_node *np = ofdev->dev.of_node;
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255 struct net_device *dev;
256 struct mscan_priv *priv;
257 void __iomem *base;
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258 const char *clock_name = NULL;
259 int irq, mscan_clksrc = 0;
260 int err = -ENOMEM;
afa17a50 261
bf3af547 262 base = of_iomap(np, 0);
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263 if (!base) {
264 dev_err(&ofdev->dev, "couldn't ioremap\n");
bf3af547 265 return err;
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266 }
267
268 irq = irq_of_parse_and_map(np, 0);
269 if (!irq) {
270 dev_err(&ofdev->dev, "no irq found\n");
271 err = -ENODEV;
272 goto exit_unmap_mem;
273 }
274
275 dev = alloc_mscandev();
bf3af547 276 if (!dev)
afa17a50 277 goto exit_dispose_irq;
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278
279 priv = netdev_priv(dev);
280 priv->reg_base = base;
281 dev->irq = irq;
282
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283 clock_name = of_get_property(np, "fsl,mscan-clock-source", NULL);
284
285 BUG_ON(!data);
286 priv->type = data->type;
287 priv->can.clock.freq = data->get_clock(ofdev, clock_name,
288 &mscan_clksrc);
afa17a50 289 if (!priv->can.clock.freq) {
bf3af547 290 dev_err(&ofdev->dev, "couldn't get MSCAN clock properties\n");
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291 goto exit_free_mscan;
292 }
293
294 SET_NETDEV_DEV(dev, &ofdev->dev);
295
bf3af547 296 err = register_mscandev(dev, mscan_clksrc);
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297 if (err) {
298 dev_err(&ofdev->dev, "registering %s failed (err=%d)\n",
299 DRV_NAME, err);
300 goto exit_free_mscan;
301 }
302
303 dev_set_drvdata(&ofdev->dev, dev);
304
305 dev_info(&ofdev->dev, "MSCAN at 0x%p, irq %d, clock %d Hz\n",
306 priv->reg_base, dev->irq, priv->can.clock.freq);
307
308 return 0;
309
310exit_free_mscan:
311 free_candev(dev);
312exit_dispose_irq:
313 irq_dispose_mapping(irq);
314exit_unmap_mem:
315 iounmap(base);
bf3af547 316
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317 return err;
318}
319
320static int __devexit mpc5xxx_can_remove(struct of_device *ofdev)
321{
322 struct net_device *dev = dev_get_drvdata(&ofdev->dev);
323 struct mscan_priv *priv = netdev_priv(dev);
324
325 dev_set_drvdata(&ofdev->dev, NULL);
326
327 unregister_mscandev(dev);
328 iounmap(priv->reg_base);
329 irq_dispose_mapping(dev->irq);
330 free_candev(dev);
331
332 return 0;
333}
334
335#ifdef CONFIG_PM
336static struct mscan_regs saved_regs;
337static int mpc5xxx_can_suspend(struct of_device *ofdev, pm_message_t state)
338{
339 struct net_device *dev = dev_get_drvdata(&ofdev->dev);
340 struct mscan_priv *priv = netdev_priv(dev);
341 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
342
343 _memcpy_fromio(&saved_regs, regs, sizeof(*regs));
344
345 return 0;
346}
347
348static int mpc5xxx_can_resume(struct of_device *ofdev)
349{
350 struct net_device *dev = dev_get_drvdata(&ofdev->dev);
351 struct mscan_priv *priv = netdev_priv(dev);
352 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
353
354 regs->canctl0 |= MSCAN_INITRQ;
0285e7ce 355 while (!(regs->canctl1 & MSCAN_INITAK))
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356 udelay(10);
357
358 regs->canctl1 = saved_regs.canctl1;
359 regs->canbtr0 = saved_regs.canbtr0;
360 regs->canbtr1 = saved_regs.canbtr1;
361 regs->canidac = saved_regs.canidac;
362
363 /* restore masks, buffers etc. */
364 _memcpy_toio(&regs->canidar1_0, (void *)&saved_regs.canidar1_0,
365 sizeof(*regs) - offsetof(struct mscan_regs, canidar1_0));
366
367 regs->canctl0 &= ~MSCAN_INITRQ;
368 regs->cantbsel = saved_regs.cantbsel;
369 regs->canrier = saved_regs.canrier;
370 regs->cantier = saved_regs.cantier;
371 regs->canctl0 = saved_regs.canctl0;
372
373 return 0;
374}
375#endif
376
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377static struct mpc5xxx_can_data __devinitdata mpc5200_can_data = {
378 .type = MSCAN_TYPE_MPC5200,
379 .get_clock = mpc52xx_can_get_clock,
380};
381
382static struct mpc5xxx_can_data __devinitdata mpc5121_can_data = {
383 .type = MSCAN_TYPE_MPC5121,
384 .get_clock = mpc512x_can_get_clock,
385};
386
afa17a50 387static struct of_device_id __devinitdata mpc5xxx_can_table[] = {
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388 { .compatible = "fsl,mpc5200-mscan", .data = &mpc5200_can_data, },
389 /* Note that only MPC5121 Rev. 2 (and later) is supported */
390 { .compatible = "fsl,mpc5121-mscan", .data = &mpc5121_can_data, },
afa17a50
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391 {},
392};
393
394static struct of_platform_driver mpc5xxx_can_driver = {
4018294b
GL
395 .driver = {
396 .name = "mpc5xxx_can",
397 .owner = THIS_MODULE,
398 .of_match_table = mpc5xxx_can_table,
399 },
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400 .probe = mpc5xxx_can_probe,
401 .remove = __devexit_p(mpc5xxx_can_remove),
402#ifdef CONFIG_PM
403 .suspend = mpc5xxx_can_suspend,
404 .resume = mpc5xxx_can_resume,
405#endif
afa17a50
WS
406};
407
408static int __init mpc5xxx_can_init(void)
409{
410 return of_register_platform_driver(&mpc5xxx_can_driver);
411}
412module_init(mpc5xxx_can_init);
413
414static void __exit mpc5xxx_can_exit(void)
415{
416 return of_unregister_platform_driver(&mpc5xxx_can_driver);
417};
418module_exit(mpc5xxx_can_exit);
419
420MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
bf3af547 421MODULE_DESCRIPTION("Freescale MPC5xxx CAN driver");
afa17a50 422MODULE_LICENSE("GPL v2");