4  *	(C) 2002 Hiroshi Miura   <miura@da-cha.org>
13  *      software is provided AS-IS with no warranties.
22  *	Suspend Modulation works by asserting and de-asserting the SUSP# pin
23  *	to CPU(GX1/GXLV) for configurable durations. When asserting SUSP#
31  *	32us intervals which the SUSP# pin is asserted(ON)/de-asserted(OFF)
38  *	F_eff = Fgx * ----------------------
46  *	on_duration = off_duration * (stock_freq - freq) / freq
49  *      on_duration = DURATION - off_duration
52  *---------------------------------------------------------------------------
55  *	Dec. 12, 2003	Hiroshi Miura <miura@da-cha.org>
56  *		- fix on/off register mistake
57  *		- fix cpu_khz calc when it stops cpu modulation.
59  *	Dec. 11, 2002	Hiroshi Miura <miura@da-cha.org>
60  *		- rewrite for Cyrix MediaGX Cx5510/5520 and
64  *		- cs5530_mod patch for 2.4.19-rc1.
66  *---------------------------------------------------------------------------
73  *			Suspend Modulation - Definitions		*
86 #include <asm/processor-cyrix.h>
108 #define SMISPDUP	(1<<1)	/* select how SMI re-enable suspend modulation: */
109 				/* IRQTC timer or read SMI speedup disable reg.(F1BAR[08-09h]) */
127 /* PCI bus clock - defaults to 30.000 if cpu_khz is not available */
135  * is suspended -- processing power is just 0.39% of what it used to be,
136  * though. 781.25 kHz(!) for a 200 MHz processor -- wow. */
141  * - let's say 5%. (min = maxfreq / POLICY_MIN_DIV)
179 	pci_write_config_byte(gx_params->cs55x0, reg, value);  in gx_write_byte()
208 	if ((gx_params->pci_suscfg & SUSMOD) == 0)  in gx_get_cpuspeed()
211 	return (stock_freq * gx_params->off_duration)  in gx_get_cpuspeed()
212 		/ (gx_params->on_duration + gx_params->off_duration);  in gx_get_cpuspeed()
232 	for (i = max_duration; i > 0; i--) {  in gx_validate_speed()
234 		tmp_on = i - tmp_off;  in gx_validate_speed()
237 		 * prefer it, too - lower latency */  in gx_validate_speed()
238 		if (abs(tmp_freq - khz) <= abs(old_tmp_freq - khz)) {  in gx_validate_speed()
263 	new_khz = gx_validate_speed(khz, &gx_params->on_duration,  in gx_set_cpuspeed()
264 			&gx_params->off_duration);  in gx_set_cpuspeed()
273 		switch (gx_params->cs55x0->device) {  in gx_set_cpuspeed()
275 			pmer1 = gx_params->pci_pmer1 | IRQ_SPDUP | VID_SPDUP;  in gx_set_cpuspeed()
276 			/* FIXME: need to test other values -- Zwane,Miura */  in gx_set_cpuspeed()
283 			if (gx_params->cs55x0->revision < 0x10) {  in gx_set_cpuspeed()
285 				suscfg = gx_params->pci_suscfg|SUSMOD;  in gx_set_cpuspeed()
288 				suscfg = gx_params->pci_suscfg|SUSMOD|PWRSVE;  in gx_set_cpuspeed()
293 			suscfg = gx_params->pci_suscfg | SUSMOD;  in gx_set_cpuspeed()
301 		suscfg = gx_params->pci_suscfg & ~(SUSMOD);  in gx_set_cpuspeed()
302 		gx_params->off_duration = 0;  in gx_set_cpuspeed()
303 		gx_params->on_duration = 0;  in gx_set_cpuspeed()
307 	gx_write_byte(PCI_MODOFF, gx_params->off_duration);  in gx_set_cpuspeed()
308 	gx_write_byte(PCI_MODON, gx_params->on_duration);  in gx_set_cpuspeed()
311 	pci_read_config_byte(gx_params->cs55x0, PCI_SUSCFG, &suscfg);  in gx_set_cpuspeed()
315 	gx_params->pci_suscfg = suscfg;  in gx_set_cpuspeed()
320 		gx_params->on_duration * 32, gx_params->off_duration * 32);  in gx_set_cpuspeed()
341 		return -EINVAL;  in cpufreq_gx_verify()
343 	policy->cpu = 0;  in cpufreq_gx_verify()
348 	 * within policy->min and policy->max. If it is not, policy->max  in cpufreq_gx_verify()
350 	 * policy->min may not be decreased, though. This way we guarantee a  in cpufreq_gx_verify()
353 	tmp_freq = gx_validate_speed(policy->min, &tmp1, &tmp2);  in cpufreq_gx_verify()
354 	if (tmp_freq < policy->min)  in cpufreq_gx_verify()
356 	policy->min = tmp_freq;  in cpufreq_gx_verify()
357 	if (policy->min > policy->max)  in cpufreq_gx_verify()
358 		policy->max = tmp_freq;  in cpufreq_gx_verify()
359 	tmp_freq = gx_validate_speed(policy->max, &tmp1, &tmp2);  in cpufreq_gx_verify()
360 	if (tmp_freq > policy->max)  in cpufreq_gx_verify()
361 		tmp_freq -= stock_freq / max_duration;  in cpufreq_gx_verify()
362 	policy->max = tmp_freq;  in cpufreq_gx_verify()
363 	if (policy->max < policy->min)  in cpufreq_gx_verify()
364 		policy->max = policy->min;  in cpufreq_gx_verify()
383 		return -EINVAL;  in cpufreq_gx_target()
385 	policy->cpu = 0;  in cpufreq_gx_target()
388 	while (tmp_freq < policy->min) {  in cpufreq_gx_target()
392 	while (tmp_freq > policy->max) {  in cpufreq_gx_target()
393 		tmp_freq -= stock_freq / max_duration;  in cpufreq_gx_target()
406 	if (!policy || policy->cpu != 0)  in cpufreq_gx_cpu_init()
407 		return -ENODEV;  in cpufreq_gx_cpu_init()
422 	policy->cpu = 0;  in cpufreq_gx_cpu_init()
425 		policy->min = maxfreq / max_duration;  in cpufreq_gx_cpu_init()
427 		policy->min = maxfreq / POLICY_MIN_DIV;  in cpufreq_gx_cpu_init()
428 	policy->max = maxfreq;  in cpufreq_gx_cpu_init()
429 	policy->cpuinfo.min_freq = maxfreq / max_duration;  in cpufreq_gx_cpu_init()
430 	policy->cpuinfo.max_freq = maxfreq;  in cpufreq_gx_cpu_init()
445 	.name		= "gx-suspmod",
457 		return -ENODEV;  in cpufreq_gx_init()
467 		return -ENOMEM;  in cpufreq_gx_init()
469 	params->cs55x0 = gx_pci;  in cpufreq_gx_init()
473 	pci_read_config_byte(params->cs55x0, PCI_SUSCFG, &(params->pci_suscfg));  in cpufreq_gx_init()
474 	pci_read_config_byte(params->cs55x0, PCI_PMER1, &(params->pci_pmer1));  in cpufreq_gx_init()
475 	pci_read_config_byte(params->cs55x0, PCI_PMER2, &(params->pci_pmer2));  in cpufreq_gx_init()
476 	pci_read_config_byte(params->cs55x0, PCI_MODON, &(params->on_duration));  in cpufreq_gx_init()
477 	pci_read_config_byte(params->cs55x0, PCI_MODOFF,  in cpufreq_gx_init()
478 			&(params->off_duration));  in cpufreq_gx_init()
492 	pci_dev_put(gx_params->cs55x0);  in cpufreq_gx_exit()
496 MODULE_AUTHOR("Hiroshi Miura <miura@da-cha.org>");