[CPUFREQ] Update ARM CPUFREQ drivers

A 4 patch set from Dominik Brodowski, tested and fixed up by rmk
for ARM.

(1)

- the system3.c cpufreq notifier couldn't possibly compile before because
      cpufreq_updateminmax has been undefined for ages.
- clean up sa1100fb.c notifier to specify exactly what's left TBD.
- double #include of cpufreq.c in drivers/pcmcia/sa1100_generic.c

(2)

Split up config symbols, add help text for CPU_FREQ_PROC_INTF

(3)

- update the Integrator CPUfreq driver so that it can get along with
  cpufreq policies.
- modularize Integrator CPUfreq driver (all it did with
  !CONFIG_CPU_FREQ was to print out some debug information)

(4)

- update the SA11x0 CPUfreq drivers so that they can get along with
  cpufreq policies and governors.
- update the cpufreq core so that cpufreq_get() returns something
  sensible during the first ->setpolicy or ->target call.

arch/arm/Kconfig

@@ -534,15 +534,43 @@ config CPU_FREQ
 	  written) to implement the policy. If you don't understand what this
 	  is all about, it's safe to say 'N'.
 
+config CPU_FREQ_SA1100
+	bool
+	depends on CPU_FREQ && SA1100_LART
+	default y
+
+config CPU_FREQ_SA1110
+	bool
+	depends on CPU_FREQ && (SA1100_ASSABET || SA1100_CERF || SA1100_PT_SYSTEM3)
+	default y
+
+config CPU_FREQ_INTEGRATOR
+	tristate "CPUfreq driver for ARM Integrator CPUs"
+	depends on ARCH_INTEGRATOR && CPU_FREQ
+	default y
+	help
+	  This enables the CPUfreq driver for ARM Integrator CPUs.
+
+	  For details, take a look at linux/Documentation/cpufreq.
+
+	  If in doubt, say Y.
+
 config CPU_FREQ_24_API
 	bool
 	depends on CPU_FREQ
 	default y
 
 config CPU_FREQ_PROC_INTF
-	tristate
-	depends on CPU_FREQ
-	default y
+	tristate "/proc/cpufreq interface (deprecated)"
+	depends on CPU_FREQ && PROC_FS
+	help
+	  This enables the /proc/cpufreq interface for controlling
+	  CPUFreq. Please note that it is recommended to use the sysfs
+	  interface instead (which is built automatically).
+
+	  For details, take a look at linux/Documentation/cpufreq.
+
+	  If in doubt, say N.
 
 source "drivers/pci/Kconfig"
 

arch/arm/mach-integrator/Makefile

@@ -4,10 +4,11 @@
 
 # Object file lists.
 
-obj-y			:= arch.o cpu.o irq.o mm.o time.o
+obj-y			:= arch.o irq.o mm.o time.o
 obj-m			:=
 obj-n			:=
 obj-			:=
 
 obj-$(CONFIG_LEDS)	+= leds.o
 obj-$(CONFIG_PCI)	+= pci_v3.o pci.o
+obj-$(CONFIG_CPU_FREQ_INTEGRATOR)	+= cpu.o

arch/arm/mach-integrator/cpu.c

@@ -23,6 +23,8 @@
 #include <asm/hardware.h>
 #include <asm/io.h>
 
+static struct cpufreq_driver integrator_driver;
+
 #define CM_ID  	(IO_ADDRESS(INTEGRATOR_HDR_BASE)+INTEGRATOR_HDR_ID_OFFSET)
 #define CM_OSC	(IO_ADDRESS(INTEGRATOR_HDR_BASE)+INTEGRATOR_HDR_OSC_OFFSET)
 #define CM_STAT (IO_ADDRESS(INTEGRATOR_HDR_BASE)+INTEGRATOR_HDR_STAT_OFFSET)
@@ -43,7 +45,6 @@ static unsigned int vco_to_freq(struct vco vco, int factor)
 	return 2000 * (vco.vdw + 8) / cc_divisor[vco.od] / factor;
 }
 
-#ifdef CONFIG_CPU_FREQ
 /*
  * Divisor indexes in ascending divisor order
  */
@@ -69,21 +70,17 @@ static struct vco freq_to_vco(unsigned int freq_khz, int factor)
 	return vco;
 }
 
+
 /*
- * Validate the speed in khz.  If it is outside our
- * range, then return the lowest.
+ * Validate the speed policy.
  */
-static int integrator_verify_speed(struct cpufreq_policy *policy)
+static int integrator_verify_policy(struct cpufreq_policy *policy)
 {
 	struct vco vco;
 
-	if (policy->max > policy->cpuinfo.max_freq)
-		policy->max = policy->cpuinfo.max_freq;
-
-	if (policy->max < 12000)
-		policy->max = 12000;
-	if (policy->max > 160000)
-		policy->max = 160000;
+	cpufreq_verify_within_limits(policy, 
+				     policy->cpuinfo.min_freq, 
+				     policy->cpuinfo.max_freq);
 
 	vco = freq_to_vco(policy->max, 1);
 
@@ -92,12 +89,28 @@ static int integrator_verify_speed(struct cpufreq_policy *policy)
 	if (vco.vdw > 152)
 		vco.vdw = 152;
 
-	policy->min = policy->max = vco_to_freq(vco, 1);
+	policy->max = vco_to_freq(vco, 1);
+
+	vco = freq_to_vco(policy->min, 1);
+
+	if (vco.vdw < 4)
+		vco.vdw = 4;
+	if (vco.vdw > 152)
+		vco.vdw = 152;
+
+	policy->min = vco_to_freq(vco, 1);
+
+	cpufreq_verify_within_limits(policy, 
+				     policy->cpuinfo.min_freq, 
+				     policy->cpuinfo.max_freq);
 
 	return 0;
 }
 
-static int integrator_set_policy(struct cpufreq_policy *policy)
+
+static int integrator_set_target(struct cpufreq_policy *policy,
+				 unsigned int target_freq,
+				 unsigned int relation)
 {
 	unsigned long cpus_allowed;
 	int cpu = policy->cpu;
@@ -121,9 +134,18 @@ static int integrator_set_policy(struct cpufreq_policy *policy)
 	cm_osc = __raw_readl(CM_OSC);
 	vco.od = (cm_osc >> 8) & 7;
 	vco.vdw = cm_osc & 255;
-
 	freqs.old = vco_to_freq(vco, 1);
-	freqs.new = target_freq;
+
+	/* freq_to_vco rounds down -- so we need the next larger freq in
+	 * case of CPUFREQ_RELATION_L.
+	 */
+	if (relation == CPUFREQ_RELATION_L)
+		target_freq += 1999;
+	if (target_freq > policy->max)
+		target_freq = policy->max;
+	vco = freq_to_vco(target_freq, 1);
+	freqs.new = vco_to_freq(vco, 1);
+
 	freqs.cpu = policy->cpu;
 
 	if (freqs.old == freqs.new) {
@@ -132,7 +154,6 @@ static int integrator_set_policy(struct cpufreq_policy *policy)
 	}
 
 	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
-	vco = freq_to_vco(policy->max, 1);
 
 	cm_osc = __raw_readl(CM_OSC);
 	cm_osc &= 0xfffff800;
@@ -152,48 +173,19 @@ static int integrator_set_policy(struct cpufreq_policy *policy)
 	return 0;
 }
 
-static struct cpufreq_policy integrator_policy = {
-	.cpu		= 0,
-	.policy		= CPUFREQ_POLICY_POWERSAVE,
-	.cpuinfo	= {
-		.max_freq		= 160000,
-		.min_freq		= 12000,
-		.transition_latency	= CPUFREQ_ETERNAL,
-	},
-};
-
-static struct cpufreq_driver integrator_driver = {
-	.verify		= integrator_verify_speed,
-	.setpolicy	= integrator_set_policy,
-	.policy		= &integrator_policy,
-	.name		= "integrator",
-};
-#endif
-
-static int __init integrator_cpu_init(void)
+static int integrator_cpufreq_init(struct cpufreq *policy)
 {
-	struct cpufreq_policy *policies;
-	unsigned long cpus_allowed;
-	int cpu;
-
-	policies = kmalloc(sizeof(struct cpufreq_policy) * NR_CPUS,
-			   GFP_KERNEL);
-	if (!policies) {
-		printk(KERN_ERR "CPU: unable to allocate policies structure\n");
-		return -ENOMEM;
-	}
-
-	cpus_allowed = current->cpus_allowed;
-	for (cpu = 0; cpu < NR_CPUS; cpu++) {
+	unsigned long cus_allowed;
+	unsigned int cpu = policy->cpu;
 	u_int cm_osc, cm_stat, mem_freq_khz;
 	struct vco vco;
 
-		if (!cpu_online(cpu))
-			continue;
+	cpus_allowed = current->cpus_allowed;
 
 	set_cpus_allowed(current, 1 << cpu);
 	BUG_ON(cpu != smp_processor_id());
 
+	/* detect memory etc. */
 	cm_stat = __raw_readl(CM_STAT);
 	cm_osc = __raw_readl(CM_OSC);
 	vco.od  = (cm_osc >> 20) & 7;
@@ -207,25 +199,38 @@ static int __init integrator_cpu_init(void)
 	vco.od = (cm_osc >> 8) & 7;
 	vco.vdw = cm_osc & 255;
 
-		policies[cpu].cpu = cpu;
-		policies[cpu].policy = CPUFREQ_POLICY_POWERSAVE,
-		policies[cpu].cpuinfo.max_freq = 160000;
-		policies[cpu].cpuinfo.min_freq = 12000;
-		policies[cpu].cpuinfo.transition_latency = CPUFREQ_ETERNAL;
-		policies[cpu].min =
-		policies[cpu].max = vco_to_freq(vco, 1);
-	}
+	/* set default policy and cpuinfo */
+	policy->policy = CPUFREQ_POLICY_PERFORMANCE;
+	policy->cpuinfo.max_freq = 160000;
+	policy->cpuinfo.min_freq = 12000;
+	policy->cpuinfo.transition_latency = 1000; /* 1 ms, assumed */
+	integrator_driver.cpu_cur_freq[policy->cpu] = policy->min = policy->max = vco_to_freq(vco, 1); /* current freq */
 
 	set_cpus_allowed(current, cpus_allowed);
 
-#ifdef CONFIG_CPU_FREQ
-	integrator_driver.policy = policies;
-	cpufreq_register(&integrator_driver);
-#else
-	kfree(policies);
-#endif
-
 	return 0;
 }
 
-arch_initcall(integrator_cpu_init);
+static struct cpufreq_driver integrator_driver = {
+	.verify		= integrator_verify_policy,
+	.target		= integrator_set_target,
+	.init		= integrator_cpufreq_init,
+	.name		= "integrator",
+};
+
+static int __init integrator_cpu_init(void)
+{
+	return cpufreq_register_driver(&integrator_driver);
+}
+
+static void __exit integrator_cpu_exit(void)
+{
+	cpufreq_unregister_driver(&integrator_driver);
+}
+
+MODULE_AUTHOR ("Russell M. King");
+MODULE_DESCRIPTION ("cpufreq driver for ARM Integrator CPUs");
+MODULE_LICENSE ("GPL");
+
+module_init(integrator_cpu_init);
+module_exit(integrator_cpu_exit);

arch/arm/mach-sa1100/Makefile

@@ -9,15 +9,8 @@ obj-n :=
 obj-  :=
 led-y := leds.o
 
-# This needs to be cleaned up.  We probably need to have SA1100
-# and SA1110 config symbols.
-ifeq ($(CONFIG_CPU_FREQ),y)
-obj-$(CONFIG_SA1100_ASSABET)		+= cpu-sa1110.o
-obj-$(CONFIG_SA1100_CERF)		+= cpu-sa1110.o
-obj-$(CONFIG_SA1100_HACKKIT)		+= cpu-sa1110.o
-obj-$(CONFIG_SA1100_LART)		+= cpu-sa1100.o
-obj-$(CONFIG_SA1100_PT_SYSTEM3)		+= cpu-sa1110.o
-endif
+obj-$(CONFIG_CPU_FREQ_SA1100)		+= cpu-sa1100.o
+obj-$(CONFIG_CPU_FREQ_SA1110)		+= cpu-sa1110.o
 
 # Specific board support
 obj-$(CONFIG_SA1100_ADSBITSY)		+= adsbitsy.o

arch/arm/mach-sa1100/cpu-sa1100.c

@@ -101,7 +101,7 @@ typedef struct {
 } sa1100_dram_regs_t;
 
 
-
+static struct cpufreq_driver sa1100_driver;
 
 static sa1100_dram_regs_t sa1100_dram_settings[] =
 {
@@ -176,60 +176,72 @@ static void sa1100_update_dram_timings(int current_speed, int new_speed)
 	}
 }
 
-static int sa1100_setspeed(struct cpufreq_policy *policy)
+static int sa1100_target(struct cpufreq_policy *policy,
+			 unsigned int target_freq,
+			 unsigned int relation)
 {
 	unsigned int cur = sa11x0_getspeed();
+	unsigned int new_ppcr;
+
 	struct cpufreq_freqs freqs;
+	switch(relation){
+	case CPUFREQ_RELATION_L:
+		new_ppcr = sa11x0_freq_to_ppcr(target_freq);
+		if (sa11x0_ppcr_to_freq(new_ppcr) > policy->max)
+			new_ppcr--;
+		break;
+	case CPUFREQ_RELATION_H:
+		new_ppcr = sa11x0_freq_to_ppcr(target_freq);
+		if ((sa11x0_ppcr_to_freq(new_ppcr) > target_freq) &&
+		    (sa11x0_ppcr_to_freq(new_ppcr - 1) >= policy->min))
+			mew_ppcr--;
+		break;
+	}
 
 	freqs.old = cur;
-	freqs.new = policy->max;
+	freqs.new = sa11x0_ppcr_to_freq(new_ppcr);
 	freqs.cpu = 0;
 
 	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 
-	if (policy->max > cur)
-		sa1100_update_dram_timings(cur, policy->max);
+	if (freqs.new > cur)
+		sa1100_update_dram_timings(cur, freqs.new);
 
-	PPCR = sa11x0_freq_to_ppcr(policy->max);
+	PPCR = new_ppcr;
 
-	if (policy->max < cur)
-		sa1100_update_dram_timings(cur, policy->max);
+	if (freqs.new < cur)
+		sa1100_update_dram_timings(cur, freqs.new);
 
 	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 
 	return 0;
 }
 
-static struct cpufreq_policy sa1100_policy = {
-	.cpu		= 0,
-	.policy		= CPUFREQ_POLICY_POWERSAVE,
-	.cpuinfo	= {
-		.max_freq		= 287000,
-		.min_freq		= 59000,
-		.transition_latency	= CPUFREQ_ETERNAL,
-	},
-};
+static int __init sa1100_cpu_init(struct cpufreq_policy *policy)
+{
+	if (policy->cpu != 0)
+		return -EINVAL;
+	sa1100_driver.cpu_cur_freq[policy->cpu] = policy->min = policy->max = sa11x0_getspeed();
+	policy->policy = CPUFREQ_POLICY_POWERSAVE;
+	policy->cpuinfo.min_freq = 59000;
+	policy->cpuinfo.max_freq = 287000;
+	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
+	return 0;
+}
 
 static struct cpufreq_driver sa1100_driver = {
 	.verify		= sa11x0_verify_speed,
-	.setpolicy	= sa1100_setspeed,
-	.policy		= &sa1100_policy,
+	.target		= sa1100_target,
+	.init		= sa1100_cpu_init,
 	.name		= "sa1100",
 };
 
 static int __init sa1100_dram_init(void)
 {
-	int ret = -ENODEV;
-
-	if ((processor_id & CPU_SA1100_MASK) == CPU_SA1100_ID) {
-		sa1100_driver.cpu_cur_freq[0] =
-		sa1100_policy.min =
-		sa1100_policy.max = sa11x0_getspeed();
-
-		ret = cpufreq_register(&sa1100_driver);
-	}
-
-	return ret;
+	if ((processor_id & CPU_SA1100_MASK) == CPU_SA1100_ID)
+		return cpufreq_register_driver(&sa1100_driver);
+	else
+		return -ENODEV;
 }
 
 arch_initcall(sa1100_dram_init);

arch/arm/mach-sa1100/cpu-sa1110.c

@@ -32,6 +32,8 @@
 
 #undef DEBUG
 
+static struct cpufreq_driver sa1110_driver;
+
 struct sdram_params {
 	u_char  rows;		/* bits				 */
 	u_char  cas_latency;	/* cycles			 */
@@ -208,11 +210,11 @@ sdram_update_refresh(u_int cpu_khz, struct sdram_params *sdram)
 }
 
 /*
- * Ok, set the CPU frequency.  Since we've done the validation
- * above, we can match for an exact frequency.  If we don't find
- * an exact match, we will to set the lowest frequency to be safe.
+ * Ok, set the CPU frequency.  
  */
-static int sa1110_setspeed(struct cpufreq_policy *policy)
+static int sa1110_target(struct cpufreq_policy *policy,
+			 unsigned int target_freq,
+			 unsigned int relation)
 {
 	struct sdram_params *sdram = &sdram_params;
 	struct cpufreq_freqs freqs;
@@ -220,8 +222,25 @@ static int sa1110_setspeed(struct cpufreq_policy *policy)
 	unsigned long flags;
 	unsigned int ppcr, unused;
 
-	ppcr = sa11x0_freq_to_ppcr(policy->max);
-	sdram_calculate_timing(&sd, policy->max, sdram);
+	switch(relation){
+	case CPUFREQ_RELATION_L:
+		ppcr = sa11x0_freq_to_ppcr(target_freq);
+		if (sa11x0_ppcr_to_freq(ppcr) > policy->max)
+			ppcr--;
+		break;
+	case CPUFREQ_RELATION_H:
+		ppcr = sa11x0_freq_to_ppcr(target_freq);
+		if (ppcr && (sa11x0_ppcr_to_freq(ppcr) > target_freq) &&
+		    (sa11x0_ppcr_to_freq(ppcr-1) >= policy->min))
+			ppcr--;
+		break;
+	}
+
+	freqs.old = sa11x0_getspeed();
+	freqs.new = sa11x0_ppcr_to_freq(ppcr);
+	freqs.cpu = 0;
+
+	sdram_calculate_timing(&sd, freqs.new, sdram);
 
 #if 0
 	/*
@@ -240,10 +259,6 @@ static int sa1110_setspeed(struct cpufreq_policy *policy)
 	sd.mdcas[2] = 0xaaaaaaaa;
 #endif
 
-	freqs.old = sa11x0_getspeed();
-	freqs.new = policy->max;
-	freqs.cpu = 0;
-
 	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 
 	/*
@@ -288,27 +303,29 @@ static int sa1110_setspeed(struct cpufreq_policy *policy)
 	/*
 	 * Now, return the SDRAM refresh back to normal.
 	 */
-	sdram_update_refresh(policy->max, sdram);
+	sdram_update_refresh(freqs.new, sdram);
 
 	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 
 	return 0;
 }
 
-static struct cpufreq_policy sa1110_policy = {
-	.cpu		= 0,
-	.policy		= CPUFREQ_POLICY_POWERSAVE,
-	.cpuinfo	= {
-		.max_freq		= 287000,
-		.min_freq		= 59000,
-		.transition_latency	= CPUFREQ_ETERNAL,
-	},
-};
+static int __init sa1110_cpu_init(struct cpufreq_policy *policy)
+{
+	if (policy->cpu != 0)
+		return -EINVAL;
+	sa1110_driver.cpu_cur_freq[policy->cpu] = policy->min = policy->max = sa11x0_getspeed();
+	policy->policy = CPUFREQ_POLICY_POWERSAVE;
+	policy->cpuinfo.min_freq = 59000;
+	policy->cpuinfo.max_freq = 287000;
+	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
+	return 0;
+}
 
 static struct cpufreq_driver sa1110_driver = {
 	.verify		= sa11x0_verify_speed,
-	.setpolicy	 = sa1110_setspeed,
-	.policy		 = &sa1110_policy,
+	.target		= sa1110_target,
+	.init		= sa1110_cpu_init,
 	.name		= "sa1110",
 };
 
@@ -333,13 +350,7 @@ static int __init sa1110_clk_init(void)
 
 		memcpy(&sdram_params, sdram, sizeof(sdram_params));
 
-		sa1110_driver.cpu_cur_freq[0] =
-		sa1110_policy.min =
-		sa1110_policy.max = sa11x0_getspeed();
-
-		sa1110_setspeed(&sa1110_policy);
-
-		return cpufreq_register(&sa1110_driver);
+		return cpufreq_register_driver(&sa1110_driver);
 	}
 
 	return 0;

arch/arm/mach-sa1100/generic.c

@@ -48,33 +48,48 @@ static const unsigned short cclk_frequency_100khz[NR_FREQS] = {
 	2802    /* 280.2 MHz */
 };
 
-#ifdef CONFIG_CPU_FREQ
+#if defined(CONFIG_CPU_FREQ_SA1100) || defined(CONFIG_CPU_FREQ_SA1110)
+/* rounds up(!)  */
 unsigned int sa11x0_freq_to_ppcr(unsigned int khz)
 {
 	int i;
 
 	khz /= 100;
 
-	for (i = NR_FREQS - 1; i > 0; i--)
-		if (cclk_frequency_100khz[i] <= khz)
+	for (i = 0; i < NR_FREQS; i++)
+		if (cclk_frequency_100khz[i] >= khz)
 			break;
 
 	return i;
 }
 
-/*
- * Validate the policy.  We aren't able to do any fancy in-kernel
- * scaling, so we force min=max, and set the policy to "performance".
- * If we can't generate the precise frequency requested, round it up.
+unsigned int sa11x0_ppcr_to_freq(unsigned int idx)
+{
+	if (idx >= NR_FREQS)
+		return 0;
+	else
+		return cclk_frequency_100khz[idx];
+}
+
+
+/* make sure that only the "userspace" governor is run -- anything else wouldn't make sense on
+ * this platform, anyway.
  */
 int sa11x0_verify_speed(struct cpufreq_policy *policy)
 {
-	if (policy->max > policy->cpuinfo.max_freq)
-		policy->max = policy->cpuinfo.max_freq;
+	unsigned int tmp;
+	if (policy->cpu)
+		return -EINVAL;
+
+	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq);
+
+	/* make sure that at least one frequency is within the policy */
+	tmp = cclk_frequency_100khz[sa11x0_freq_to_ppcr(policy->min)] * 100;
+	if (tmp > policy->max)
+		policy->max = tmp;
+
+	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq);
 
-	policy->max = cclk_frequency_100khz[sa11x0_freq_to_ppcr(policy->max)] * 100;
-	policy->min = policy->max;
-	policy->policy = CPUFREQ_POLICY_POWERSAVE;
 	return 0;
 }
 

arch/arm/mach-sa1100/generic.h

@@ -23,3 +23,4 @@ struct cpufreq_policy;
 extern unsigned int sa11x0_freq_to_ppcr(unsigned int khz);
 extern int sa11x0_verify_speed(struct cpufreq_policy *policy);
 extern unsigned int sa11x0_getspeed(void);
+extern unsigned int sa11x0_ppcr_to_freq(unsigned int idx);

arch/arm/mach-sa1100/system3.c

@@ -213,11 +213,17 @@ static void __init system3_init_irq(void)
 static int sdram_notifier(struct notifier_block *nb, unsigned long event,
 		void *data)
 {
+	struct cpufreq_policy *policy = data;
 	switch (event) {
-		case CPUFREQ_MINMAX:
-			cpufreq_updateminmax(data, 147500, 206000);
+		case CPUFREQ_ADJUST:
+		case CPUFREQ_INCOMPATIBLE:
+			cpufreq_verify_within_limits(policy, 147500, 206000);
+			break;
+		case CPUFREQ_NOTIFY:
+			if ((policy->min < 147500) || 
+			    (policy->max > 206000))
+				panic("cpufreq failed to limit the speed\n");
 			break;
-
 	}
 	return 0;
 }
@@ -405,7 +411,7 @@ static int __init system3_init(void)
 		goto DONE;
 	}
 
-#if defined( CONFIG_CPU_FREQ )
+#ifdef CONFIG_CPU_FREQ
 	ret = cpufreq_register_notifier(&system3_clkchg_block);
 	if ( ret != 0 ) {
 		printk( KERN_WARNING"PT Digital Board: could not register clock scale callback\n" );

drivers/pcmcia/sa1100_generic.c

@@ -47,7 +47,6 @@
 #include <linux/notifier.h>
 #include <linux/proc_fs.h>
 #include <linux/version.h>
-#include <linux/cpufreq.h>
 
 #include <pcmcia/version.h>
 #include <pcmcia/cs_types.h>

drivers/video/sa1100fb.c

@@ -1590,11 +1590,21 @@ sa1100fb_freq_policy(struct notifier_block *nb, unsigned long val,
 	struct sa1100fb_info *fbi = TO_INF(nb, freq_policy);
 	struct cpufreq_policy *policy = data;
 
-	if (val == CPUFREQ_INCOMPATIBLE) {
+	switch (val) {
+	case CPUFREQ_ADJUST:
+	case CPUFREQ_INCOMPATIBLE:
 		printk(KERN_DEBUG "min dma period: %d ps, "
 			"new clock %d kHz\n", sa1100fb_min_dma_period(fbi),
 			policy->max);
 		/* todo: fill in min/max values */
+		break;
+	case CPUFREQ_NOTIFY:
+		do {} while(0);
+		/* todo: panic if min/max values aren't fulfilled 
+		 * [can't really happen unless there's a bug in the
+		 * CPU policy verififcation process *
+		 */
+		break;
 	}
 	return 0;
 }

kernel/cpufreq.c

@@ -336,6 +336,13 @@ static int cpufreq_add_dev (struct device * dev)
 	       &cpufreq_driver->policy[cpu], 
 	       sizeof(struct cpufreq_policy));
 
+	/* 2.4-API init for this CPU */
+#ifdef CONFIG_CPU_FREQ_24_API
+	cpu_min_freq[cpu] = cpufreq_driver->policy[cpu].cpuinfo.min_freq;
+	cpu_max_freq[cpu] = cpufreq_driver->policy[cpu].cpuinfo.max_freq;
+	cpu_cur_freq[cpu] = cpufreq_driver->cpu_cur_freq[cpu];
+#endif
+
 	if (cpufreq_driver->target)
 		cpufreq_governor(cpu, CPUFREQ_GOV_START);