static void wf_smu_create_cpu_fans()

in windfarm_pm81.c [393:470]

• 59 lines of code
• 7 McCabe index (conditional complexity)

static void wf_smu_create_cpu_fans(void)
{
	struct wf_cpu_pid_param pid_param;
	const struct smu_sdbp_header *hdr;
	struct smu_sdbp_cpupiddata *piddata;
	struct smu_sdbp_fvt *fvt;
	s32 tmax, tdelta, maxpow, powadj;

	/* First, locate the PID params in SMU SBD */
	hdr = smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID, NULL);
	if (hdr == 0) {
		printk(KERN_WARNING "windfarm: CPU PID fan config not found "
		       "max fan speed\n");
		goto fail;
	}
	piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];

	/* Get the FVT params for operating point 0 (the only supported one
	 * for now) in order to get tmax
	 */
	hdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL);
	if (hdr) {
		fvt = (struct smu_sdbp_fvt *)&hdr[1];
		tmax = ((s32)fvt->maxtemp) << 16;
	} else
		tmax = 0x5e0000; /* 94 degree default */

	/* Alloc & initialize state */
	wf_smu_cpu_fans = kmalloc(sizeof(struct wf_smu_cpu_fans_state),
				  GFP_KERNEL);
	if (wf_smu_cpu_fans == NULL)
		goto fail;
       	wf_smu_cpu_fans->ticks = 1;

	wf_smu_cpu_fans->scale = WF_SMU_CPU_FANS_SIBLING_SCALE;
	wf_smu_cpu_fans->offset = WF_SMU_CPU_FANS_SIBLING_OFFSET;

	/* Fill PID params */
	pid_param.interval = WF_SMU_CPU_FANS_INTERVAL;
	pid_param.history_len = piddata->history_len;
	if (pid_param.history_len > WF_CPU_PID_MAX_HISTORY) {
		printk(KERN_WARNING "windfarm: History size overflow on "
		       "CPU control loop (%d)\n", piddata->history_len);
		pid_param.history_len = WF_CPU_PID_MAX_HISTORY;
	}
	pid_param.gd = piddata->gd;
	pid_param.gp = piddata->gp;
	pid_param.gr = piddata->gr / pid_param.history_len;

	tdelta = ((s32)piddata->target_temp_delta) << 16;
	maxpow = ((s32)piddata->max_power) << 16;
	powadj = ((s32)piddata->power_adj) << 16;

	pid_param.tmax = tmax;
	pid_param.ttarget = tmax - tdelta;
	pid_param.pmaxadj = maxpow - powadj;

	pid_param.min = wf_control_get_min(fan_cpu_main);
	pid_param.max = wf_control_get_max(fan_cpu_main);

	wf_cpu_pid_init(&wf_smu_cpu_fans->pid, &pid_param);

	DBG("wf: CPU Fan control initialized.\n");
	DBG("    ttarget=%d.%03d, tmax=%d.%03d, min=%d RPM, max=%d RPM\n",
	    FIX32TOPRINT(pid_param.ttarget), FIX32TOPRINT(pid_param.tmax),
	    pid_param.min, pid_param.max);

	return;

 fail:
	printk(KERN_WARNING "windfarm: CPU fan config not found\n"
	       "for this machine model, max fan speed\n");

	if (cpufreq_clamp)
		wf_control_set_max(cpufreq_clamp);
	if (fan_cpu_main)
		wf_control_set_max(fan_cpu_main);
}