powernow-k8.c

来自「优龙2410linux2.6.8内核源代码」· C语言 代码 · 共 1,121 行 · 第 1/2 页

	if (!powernow_table) {
		printk(KERN_ERR PFX "powernow_table memory alloc failure\n");
		return -ENOMEM;
	}

	for (j = 0; j < data->numps; j++) {
		powernow_table[j].index = pst[j].fid; /* lower 8 bits */
		powernow_table[j].index |= (pst[j].vid << 8); /* upper 8 bits */
		powernow_table[j].frequency = find_khz_freq_from_fid(pst[j].fid);
	}
	powernow_table[data->numps].frequency = CPUFREQ_TABLE_END;
	powernow_table[data->numps].index = 0;

	if (query_current_values_with_pending_wait(data)) {
		kfree(powernow_table);
		return -EIO;
	}

	dprintk(KERN_INFO PFX "cfid 0x%x, cvid 0x%x\n", data->currfid, data->currvid);
	data->powernow_table = powernow_table;
	print_basics(data);

	for (j = 0; j < data->numps; j++)
		if ((pst[j].fid==data->currfid) && (pst[j].vid==data->currvid))
			return 0;

	dprintk(KERN_ERR PFX "currfid/vid do not match PST, ignoring\n");
	return 0;
}

/* Find and validate the PSB/PST table in BIOS. */
static int find_psb_table(struct powernow_k8_data *data)
{
	struct psb_s *psb;
	unsigned int i;
	u32 mvs;
	u8 maxvid;

	for (i = 0xc0000; i < 0xffff0; i += 0x10) {
		/* Scan BIOS looking for the signature. */
		/* It can not be at ffff0 - it is too big. */

		psb = phys_to_virt(i);
		if (memcmp(psb, PSB_ID_STRING, PSB_ID_STRING_LEN) != 0)
			continue;

		dprintk(KERN_DEBUG PFX "found PSB header at 0x%p\n", psb);

		dprintk(KERN_DEBUG PFX "table vers: 0x%x\n", psb->tableversion);
		if (psb->tableversion != PSB_VERSION_1_4) {
			printk(KERN_INFO BFX "PSB table is not v1.4\n");
			return -ENODEV;
		}

		dprintk(KERN_DEBUG PFX "flags: 0x%x\n", psb->flags1);
		if (psb->flags1) {
			printk(KERN_ERR BFX "unknown flags\n");
			return -ENODEV;
		}

		data->vstable = psb->voltagestabilizationtime;
		dprintk(KERN_INFO PFX "voltage stabilization time: %d(*20us)\n", data->vstable);

		dprintk(KERN_DEBUG PFX "flags2: 0x%x\n", psb->flags2);
		data->rvo = psb->flags2 & 3;
		data->irt = ((psb->flags2) >> 2) & 3;
		mvs = ((psb->flags2) >> 4) & 3;
		data->vidmvs = 1 << mvs;
		data->batps = ((psb->flags2) >> 6) & 3;

		dprintk(KERN_INFO PFX "ramp voltage offset: %d\n", data->rvo);
		dprintk(KERN_INFO PFX "isochronous relief time: %d\n", data->irt);
		dprintk(KERN_INFO PFX "maximum voltage step: %d - 0x%x\n", mvs, data->vidmvs);

		dprintk(KERN_DEBUG PFX "numpst: 0x%x\n", psb->numpst);
		if (psb->numpst != 1) {
			printk(KERN_ERR BFX "numpst must be 1\n");
			return -ENODEV;
		}

		data->plllock = psb->plllocktime;
		dprintk(KERN_INFO PFX "plllocktime: 0x%x (units 1us)\n", psb->plllocktime);
		dprintk(KERN_INFO PFX "maxfid: 0x%x\n", psb->maxfid);
		dprintk(KERN_INFO PFX "maxvid: 0x%x\n", psb->maxvid);
		maxvid = psb->maxvid;

		data->numps = psb->numpstates;
		dprintk(KERN_INFO PFX "numpstates: 0x%x\n", data->numps);
		return fill_powernow_table(data, (struct pst_s *)(psb+1), maxvid);
	}
	/*
	 * If you see this message, complain to BIOS manufacturer. If
	 * he tells you "we do not support Linux" or some similar
	 * nonsense, remember that Windows 2000 uses the same legacy
	 * mechanism that the old Linux PSB driver uses. Tell them it
	 * is broken with Windows 2000.
	 *
	 * The reference to the AMD documentation is chapter 9 in the
	 * BIOS and Kernel Developer's Guide, which is available on
	 * www.amd.com
	 */
	printk(KERN_ERR PFX "BIOS error - no PSB\n");
	return -ENODEV;
}

#if defined(CONFIG_ACPI_PROCESSOR) || defined(CONFIG_ACPI_PROCESSOR_MODULE)
static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index)
{
	if (!data->acpi_data.state_count)
		return;

	data->irt = (data->acpi_data.states[index].control >> IRT_SHIFT) & IRT_MASK;
	data->rvo = (data->acpi_data.states[index].control >> RVO_SHIFT) & RVO_MASK;
	data->plllock = (data->acpi_data.states[index].control >> PLL_L_SHIFT) & PLL_L_MASK;
	data->vidmvs = 1 << ((data->acpi_data.states[index].control >> MVS_SHIFT) & MVS_MASK);
	data->vstable = (data->acpi_data.states[index].control >> VST_SHIFT) & VST_MASK;
}

static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
{
	int i;
	int cntlofreq = 0;
	struct cpufreq_frequency_table *powernow_table;

	if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
		dprintk(KERN_DEBUG PFX "register performance failed\n");
		return -EIO;
	}

	/* verify the data contained in the ACPI structures */
	if (data->acpi_data.state_count <= 1) {
		dprintk(KERN_DEBUG PFX "No ACPI P-States\n");
		goto err_out;
	}

	if ((data->acpi_data.control_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
		(data->acpi_data.status_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
		dprintk(KERN_DEBUG PFX "Invalid control/status registers\n");
		goto err_out;
	}

	/* fill in data->powernow_table */
	powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table)
		* (data->acpi_data.state_count + 1)), GFP_KERNEL);
	if (!powernow_table) {
		dprintk(KERN_ERR PFX "powernow_table memory alloc failure\n");
		goto err_out;
	}

	for (i = 0; i < data->acpi_data.state_count; i++) {
		u32 fid = data->acpi_data.states[i].control & FID_MASK;
		u32 vid = (data->acpi_data.states[i].control >> VID_SHIFT) & VID_MASK;

		dprintk(KERN_INFO PFX "   %d : fid 0x%x, vid 0x%x\n", i, fid, vid);

		powernow_table[i].index = fid; /* lower 8 bits */
		powernow_table[i].index |= (vid << 8); /* upper 8 bits */
		powernow_table[i].frequency = find_khz_freq_from_fid(fid);

		/* verify frequency is OK */
		if ((powernow_table[i].frequency > (MAX_FREQ * 1000)) ||
			(powernow_table[i].frequency < (MIN_FREQ * 1000))) {
			dprintk(KERN_INFO PFX "invalid freq %u kHz, ignoring\n", powernow_table[i].frequency);
			powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
			continue;
		}

		/* verify voltage is OK - BIOSs are using "off" to indicate invalid */
		if (vid == 0x1f) {
			dprintk(KERN_INFO PFX "invalid vid %u, ignoring\n", vid);
			powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
			continue;
		}

 		if (fid < HI_FID_TABLE_BOTTOM) {
 			if (cntlofreq) {
 				/* if both entries are the same, ignore this
 				 * one... 
 				 */
 				if ((powernow_table[i].frequency != powernow_table[cntlofreq].frequency) ||
 				    (powernow_table[i].index != powernow_table[cntlofreq].index)) {
 					printk(KERN_ERR PFX "Too many lo freq table entries\n");
 					goto err_out_mem;
 				}
				
 				dprintk(KERN_INFO PFX "double low frequency table entry, ignoring it.\n");
 				powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
 				continue;
 			} else
 				cntlofreq = i;
		}

		if (powernow_table[i].frequency != (data->acpi_data.states[i].core_frequency * 1000)) {
			printk(KERN_INFO PFX "invalid freq entries %u kHz vs. %u kHz\n",
				powernow_table[i].frequency,
				(unsigned int) (data->acpi_data.states[i].core_frequency * 1000));
			powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
			continue;
		}
	}

	powernow_table[data->acpi_data.state_count].frequency = CPUFREQ_TABLE_END;
	powernow_table[data->acpi_data.state_count].index = 0;
	data->powernow_table = powernow_table;

	/* fill in data */
	data->numps = data->acpi_data.state_count;
	print_basics(data);
	powernow_k8_acpi_pst_values(data, 0);
	return 0;

err_out_mem:
	kfree(powernow_table);

err_out:
	acpi_processor_unregister_performance(&data->acpi_data, data->cpu);

	/* data->acpi_data.state_count informs us at ->exit() whether ACPI was used */
	data->acpi_data.state_count = 0;

	return -ENODEV;
}

static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data)
{
	if (data->acpi_data.state_count)
		acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
}

#else
static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data) { return -ENODEV; }
static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data) { return; }
static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index) { return; }
#endif /* CONFIG_X86_POWERNOW_K8_ACPI */

/* Take a frequency, and issue the fid/vid transition command */
static int transition_frequency(struct powernow_k8_data *data, unsigned int index)
{
	u32 fid;
	u32 vid;
	int res;
	struct cpufreq_freqs freqs;

	dprintk(KERN_DEBUG PFX "cpu %d transition to index %u\n",
		smp_processor_id(), index );

	/* fid are the lower 8 bits of the index we stored into
	 * the cpufreq frequency table in find_psb_table, vid are 
	 * the upper 8 bits.
	 */

	fid = data->powernow_table[index].index & 0xFF;
	vid = (data->powernow_table[index].index & 0xFF00) >> 8;

	dprintk(KERN_DEBUG PFX "table matched fid 0x%x, giving vid 0x%x\n",
		fid, vid);

	if (query_current_values_with_pending_wait(data))
		return 1;

	if ((data->currvid == vid) && (data->currfid == fid)) {
		dprintk(KERN_DEBUG PFX
			"target matches current values (fid 0x%x, vid 0x%x)\n",
			fid, vid);
		return 0;
	}

	if ((fid < HI_FID_TABLE_BOTTOM) && (data->currfid < HI_FID_TABLE_BOTTOM)) {
		printk(KERN_ERR PFX
		       "ignoring illegal change in lo freq table-%x to 0x%x\n",
		       data->currfid, fid);
		return 1;
	}

	dprintk(KERN_DEBUG PFX "cpu %d, changing to fid 0x%x, vid 0x%x\n",
				smp_processor_id(), fid, vid);

	freqs.cpu = data->cpu;

	freqs.old = find_khz_freq_from_fid(data->currfid);
	freqs.new = find_khz_freq_from_fid(fid);
	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);

	down(&fidvid_sem);
	res = transition_fid_vid(data, fid, vid);
	up(&fidvid_sem);

	freqs.new = find_khz_freq_from_fid(data->currfid);
	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);

	return res;
}

/* Driver entry point to switch to the target frequency */
static int powernowk8_target(struct cpufreq_policy *pol, unsigned targfreq, unsigned relation)
{
	cpumask_t oldmask = CPU_MASK_ALL;
	struct powernow_k8_data *data = powernow_data[pol->cpu];
	u32 checkfid = data->currfid;
	u32 checkvid = data->currvid;
	unsigned int newstate;
	int ret = -EIO;

	/* only run on specific CPU from here on */
	oldmask = current->cpus_allowed;
	set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));
	schedule();

	if (smp_processor_id() != pol->cpu) {
		printk(KERN_ERR "limiting to cpu %u failed\n", pol->cpu);
		goto err_out;
	}

	if (pending_bit_stuck()) {
		printk(KERN_ERR PFX "failing targ, change pending bit set\n");
		goto err_out;
	}

	dprintk(KERN_DEBUG PFX "targ: cpu %d, %d kHz, min %d, max %d, relation %d\n",
		pol->cpu, targfreq, pol->min, pol->max, relation);

	if (query_current_values_with_pending_wait(data)) {
		ret = -EIO;
		goto err_out;
	}

	dprintk(KERN_DEBUG PFX "targ: curr fid 0x%x, vid 0x%x\n",
		data->currfid, data->currvid);

	if ((checkvid != data->currvid) || (checkfid != data->currfid)) {
		printk(KERN_ERR PFX
		       "error - out of sync, fid 0x%x 0x%x, vid 0x%x 0x%x\n",
		       checkfid, data->currfid, checkvid, data->currvid);
	}

	if (cpufreq_frequency_table_target(pol, data->powernow_table, targfreq, relation, &newstate))
		goto err_out;

	powernow_k8_acpi_pst_values(data, newstate);

	if (transition_frequency(data, newstate)) {
		printk(KERN_ERR PFX "transition frequency failed\n");
		ret = 1;
		goto err_out;
	}

	pol->cur = find_khz_freq_from_fid(data->currfid);
	ret = 0;

err_out:
	set_cpus_allowed(current, oldmask);
	schedule();

	return ret;
}

/* Driver entry point to verify the policy and range of frequencies */
static int powernowk8_verify(struct cpufreq_policy *pol)
{
	struct powernow_k8_data *data = powernow_data[pol->cpu];

	return cpufreq_frequency_table_verify(pol, data->powernow_table);
}

/* per CPU init entry point to the driver */
static int __init powernowk8_cpu_init(struct cpufreq_policy *pol)
{
	struct powernow_k8_data *data;
	cpumask_t oldmask = CPU_MASK_ALL;
	int rc;

	if (!check_supported_cpu(pol->cpu))
		return -ENODEV;

	data = kmalloc(sizeof(struct powernow_k8_data), GFP_KERNEL);
	if (!data) {
		printk(KERN_ERR PFX "unable to alloc powernow_k8_data");
		return -ENOMEM;
	}
	memset(data,0,sizeof(struct powernow_k8_data));

	data->cpu = pol->cpu;

	if (powernow_k8_cpu_init_acpi(data)) {
		/*
		 * Use the PSB BIOS structure. This is only availabe on
		 * an UP version, and is deprecated by AMD.
		 */

		if (pol->cpu != 0) {
			printk(KERN_ERR PFX "init not cpu 0\n");
			kfree(data);
			return -ENODEV;
		}
		if ((num_online_cpus() != 1) || (num_possible_cpus() != 1)) {
			printk(KERN_INFO PFX "MP systems not supported by PSB BIOS structure\n");
			kfree(data);
			return -ENODEV;
		}
		rc = find_psb_table(data);
		if (rc) {
			kfree(data);
			return -ENODEV;
		}
	}

	/* only run on specific CPU from here on */
	oldmask = current->cpus_allowed;
	set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));
	schedule();

	if (smp_processor_id() != pol->cpu) {
		printk(KERN_ERR "limiting to cpu %u failed\n", pol->cpu);
		goto err_out;
	}

	if (pending_bit_stuck()) {
		printk(KERN_ERR PFX "failing init, change pending bit set\n");
		goto err_out;
	}

	if (query_current_values_with_pending_wait(data))
		goto err_out;

	fidvid_msr_init();

	/* run on any CPU again */
	set_cpus_allowed(current, oldmask);
	schedule();

	pol->governor = CPUFREQ_DEFAULT_GOVERNOR;

	/* Take a crude guess here. 
	 * That guess was in microseconds, so multiply with 1000 */
	pol->cpuinfo.transition_latency = (((data->rvo + 8) * data->vstable * VST_UNITS_20US)
	    + (3 * (1 << data->irt) * 10)) * 1000;

	pol->cur = find_khz_freq_from_fid(data->currfid);
	dprintk(KERN_DEBUG PFX "policy current frequency %d kHz\n", pol->cur);

	/* min/max the cpu is capable of */
	if (cpufreq_frequency_table_cpuinfo(pol, data->powernow_table)) {
		printk(KERN_ERR PFX "invalid powernow_table\n");
		kfree(data->powernow_table);
		kfree(data);
		return -EINVAL;
	}

	cpufreq_frequency_table_get_attr(data->powernow_table, pol->cpu);

	printk(KERN_INFO PFX "cpu_init done, current fid 0x%x, vid 0x%x\n",
	       data->currfid, data->currvid);

	powernow_data[pol->cpu] = data;

	return 0;

err_out:
	set_cpus_allowed(current, oldmask);
	schedule();

	kfree(data);
	return -ENODEV;
}

static int __exit powernowk8_cpu_exit (struct cpufreq_policy *pol)
{
	struct powernow_k8_data *data = powernow_data[pol->cpu];

	if (!data)
		return -EINVAL;

	powernow_k8_cpu_exit_acpi(data);

	cpufreq_frequency_table_put_attr(pol->cpu);

	kfree(data->powernow_table);
	kfree(data);

	return 0;
}

static unsigned int powernowk8_get (unsigned int cpu)
{
	struct powernow_k8_data *data = powernow_data[cpu];
	cpumask_t oldmask = current->cpus_allowed;
	unsigned int khz = 0;

	set_cpus_allowed(current, cpumask_of_cpu(cpu));
	if (smp_processor_id() != cpu) {
		printk(KERN_ERR PFX "limiting to CPU %d failed in powernowk8_get\n", cpu);
		set_cpus_allowed(current, oldmask);
		return 0;
	}
	preempt_disable();

	if (query_current_values_with_pending_wait(data))
		goto out;

	khz = find_khz_freq_from_fid(data->currfid);

 out:
	preempt_enable_no_resched();
	set_cpus_allowed(current, oldmask);

	return khz;
}

static struct freq_attr* powernow_k8_attr[] = {
	&cpufreq_freq_attr_scaling_available_freqs,
	NULL,
};

static struct cpufreq_driver cpufreq_amd64_driver = {
	.verify = powernowk8_verify,
	.target = powernowk8_target,
	.init = powernowk8_cpu_init,
	.exit = powernowk8_cpu_exit,
	.get = powernowk8_get,
	.name = "powernow-k8",
	.owner = THIS_MODULE,
	.attr = powernow_k8_attr,
};

/* driver entry point for init */
static int __init powernowk8_init(void)
{
	unsigned int i, supported_cpus = 0;

	for (i=0; i<NR_CPUS; i++) {
		if (!cpu_online(i))
			continue;
		if (check_supported_cpu(i))
			supported_cpus++;
	}

	if (supported_cpus == num_online_cpus()) {
		printk(KERN_INFO PFX "Found %d AMD Athlon 64 / Opteron processors (" VERSION ")\n",
			supported_cpus);
		return cpufreq_register_driver(&cpufreq_amd64_driver);
	}

	return -ENODEV;
}

/* driver entry point for term */
static void __exit powernowk8_exit(void)
{
	dprintk(KERN_INFO PFX "exit\n");

	cpufreq_unregister_driver(&cpufreq_amd64_driver);
}

MODULE_AUTHOR("Paul Devriendt <[e-mail]>");
MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
MODULE_LICENSE("GPL");

late_initcall(powernowk8_init);
module_exit(powernowk8_exit);