[CPUFREQ] use dynamic debug instead of custom infrastructure

With dynamic debug having gained the capability to report debug messages
also during the boot process, it offers a far superior interface for
debug messages than the custom cpufreq infrastructure. As a first step,
remove the old cpufreq_debug_printk() function and replace it with a call
to the generic pr_debug() function.

How can dynamic debug be used on cpufreq? You need a kernel which has
CONFIG_DYNAMIC_DEBUG enabled.

To enabled debugging during runtime, mount debugfs and

$ echo -n 'module cpufreq +p' > /sys/kernel/debug/dynamic_debug/control

for debugging the complete "cpufreq" module. To achieve the same goal during
boot, append

	ddebug_query="module cpufreq +p"

as a boot parameter to the kernel of your choice.

For more detailled instructions, please see
Documentation/dynamic-debug-howto.txt

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Dave Jones <davej@redhat.com>

1 files changed, 22 insertions, 25 deletions

diff --git a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
index 907c8e637ef5..7b0603eb0129 100644
--- a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
+++ b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
@@ -48,9 +48,6 @@
 
 #define BUF_SZ          4
 
-#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER,      \
-                                             "pcc-cpufreq", msg)
-
 struct pcc_register_resource {
         u8 descriptor;
         u16 length;
@@ -152,7 +149,7 @@ static unsigned int pcc_get_freq(unsigned int cpu)
 
         spin_lock(&pcc_lock);
 
-        dprintk("get: get_freq for CPU %d\n", cpu);
+        pr_debug("get: get_freq for CPU %d\n", cpu);
         pcc_cpu_data = per_cpu_ptr(pcc_cpu_info, cpu);
 
         input_buffer = 0x1;
@@ -170,7 +167,7 @@ static unsigned int pcc_get_freq(unsigned int cpu)
 
         status = ioread16(&pcch_hdr->status);
         if (status != CMD_COMPLETE) {
-                dprintk("get: FAILED: for CPU %d, status is %d\n",
+                pr_debug("get: FAILED: for CPU %d, status is %d\n",
                         cpu, status);
                 goto cmd_incomplete;
         }
@@ -178,14 +175,14 @@ static unsigned int pcc_get_freq(unsigned int cpu)
         curr_freq = (((ioread32(&pcch_hdr->nominal) * (output_buffer & 0xff))
                         / 100) * 1000);
 
-        dprintk("get: SUCCESS: (virtual) output_offset for cpu %d is "
-                "0x%x, contains a value of: 0x%x. Speed is: %d MHz\n",
+        pr_debug("get: SUCCESS: (virtual) output_offset for cpu %d is "
+                "0x%p, contains a value of: 0x%x. Speed is: %d MHz\n",
                 cpu, (pcch_virt_addr + pcc_cpu_data->output_offset),
                 output_buffer, curr_freq);
 
         freq_limit = (output_buffer >> 8) & 0xff;
         if (freq_limit != 0xff) {
-                dprintk("get: frequency for cpu %d is being temporarily"
+                pr_debug("get: frequency for cpu %d is being temporarily"
                         " capped at %d\n", cpu, curr_freq);
         }
 
@@ -212,8 +209,8 @@ static int pcc_cpufreq_target(struct cpufreq_policy *policy,
         cpu = policy->cpu;
         pcc_cpu_data = per_cpu_ptr(pcc_cpu_info, cpu);
 
-        dprintk("target: CPU %d should go to target freq: %d "
-                "(virtual) input_offset is 0x%x\n",
+        pr_debug("target: CPU %d should go to target freq: %d "
+                "(virtual) input_offset is 0x%p\n",
                 cpu, target_freq,
                 (pcch_virt_addr + pcc_cpu_data->input_offset));
 
@@ -234,14 +231,14 @@ static int pcc_cpufreq_target(struct cpufreq_policy *policy,
 
         status = ioread16(&pcch_hdr->status);
         if (status != CMD_COMPLETE) {
-                dprintk("target: FAILED for cpu %d, with status: 0x%x\n",
+                pr_debug("target: FAILED for cpu %d, with status: 0x%x\n",
                         cpu, status);
                 goto cmd_incomplete;
         }
         iowrite16(0, &pcch_hdr->status);
 
         cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
-        dprintk("target: was SUCCESSFUL for cpu %d\n", cpu);
+        pr_debug("target: was SUCCESSFUL for cpu %d\n", cpu);
         spin_unlock(&pcc_lock);
 
         return 0;
@@ -293,7 +290,7 @@ static int pcc_get_offset(int cpu)
         memset_io((pcch_virt_addr + pcc_cpu_data->input_offset), 0, BUF_SZ);
         memset_io((pcch_virt_addr + pcc_cpu_data->output_offset), 0, BUF_SZ);
 
-        dprintk("pcc_get_offset: for CPU %d: pcc_cpu_data "
+        pr_debug("pcc_get_offset: for CPU %d: pcc_cpu_data "
                 "input_offset: 0x%x, pcc_cpu_data output_offset: 0x%x\n",
                 cpu, pcc_cpu_data->input_offset, pcc_cpu_data->output_offset);
 out_free:
@@ -410,7 +407,7 @@ static int __init pcc_cpufreq_probe(void)
         if (ACPI_SUCCESS(status)) {
                 ret = pcc_cpufreq_do_osc(&osc_handle);
                 if (ret)
-                        dprintk("probe: _OSC evaluation did not succeed\n");
+                        pr_debug("probe: _OSC evaluation did not succeed\n");
                 /* Firmware's use of _OSC is optional */
                 ret = 0;
         }
@@ -433,7 +430,7 @@ static int __init pcc_cpufreq_probe(void)
 
         mem_resource = (struct pcc_memory_resource *)member->buffer.pointer;
 
-        dprintk("probe: mem_resource descriptor: 0x%x,"
+        pr_debug("probe: mem_resource descriptor: 0x%x,"
                 " length: %d, space_id: %d, resource_usage: %d,"
                 " type_specific: %d, granularity: 0x%llx,"
                 " minimum: 0x%llx, maximum: 0x%llx,"
@@ -453,13 +450,13 @@ static int __init pcc_cpufreq_probe(void)
         pcch_virt_addr = ioremap_nocache(mem_resource->minimum,
                                         mem_resource->address_length);
         if (pcch_virt_addr == NULL) {
-                dprintk("probe: could not map shared mem region\n");
+                pr_debug("probe: could not map shared mem region\n");
                 goto out_free;
         }
         pcch_hdr = pcch_virt_addr;
 
-        dprintk("probe: PCCH header (virtual) addr: 0x%p\n", pcch_hdr);
-        dprintk("probe: PCCH header is at physical address: 0x%llx,"
+        pr_debug("probe: PCCH header (virtual) addr: 0x%p\n", pcch_hdr);
+        pr_debug("probe: PCCH header is at physical address: 0x%llx,"
                 " signature: 0x%x, length: %d bytes, major: %d, minor: %d,"
                 " supported features: 0x%x, command field: 0x%x,"
                 " status field: 0x%x, nominal latency: %d us\n",
@@ -469,7 +466,7 @@ static int __init pcc_cpufreq_probe(void)
                 ioread16(&pcch_hdr->command), ioread16(&pcch_hdr->status),
                 ioread32(&pcch_hdr->latency));
 
-        dprintk("probe: min time between commands: %d us,"
+        pr_debug("probe: min time between commands: %d us,"
                 " max time between commands: %d us,"
                 " nominal CPU frequency: %d MHz,"
                 " minimum CPU frequency: %d MHz,"
@@ -494,7 +491,7 @@ static int __init pcc_cpufreq_probe(void)
         doorbell.access_width = 64;
         doorbell.address = reg_resource->address;
 
-        dprintk("probe: doorbell: space_id is %d, bit_width is %d, "
+        pr_debug("probe: doorbell: space_id is %d, bit_width is %d, "
                 "bit_offset is %d, access_width is %d, address is 0x%llx\n",
                 doorbell.space_id, doorbell.bit_width, doorbell.bit_offset,
                 doorbell.access_width, reg_resource->address);
@@ -515,7 +512,7 @@ static int __init pcc_cpufreq_probe(void)
 
         doorbell_write = member->integer.value;
 
-        dprintk("probe: doorbell_preserve: 0x%llx,"
+        pr_debug("probe: doorbell_preserve: 0x%llx,"
                 " doorbell_write: 0x%llx\n",
                 doorbell_preserve, doorbell_write);
 
@@ -550,7 +547,7 @@ static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy)
 
         result = pcc_get_offset(cpu);
         if (result) {
-                dprintk("init: PCCP evaluation failed\n");
+                pr_debug("init: PCCP evaluation failed\n");
                 goto out;
         }
 
@@ -561,12 +558,12 @@ static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy)
         policy->cur = pcc_get_freq(cpu);
 
         if (!policy->cur) {
-                dprintk("init: Unable to get current CPU frequency\n");
+                pr_debug("init: Unable to get current CPU frequency\n");
                 result = -EINVAL;
                 goto out;
         }
 
-        dprintk("init: policy->max is %d, policy->min is %d\n",
+        pr_debug("init: policy->max is %d, policy->min is %d\n",
                 policy->max, policy->min);
 out:
         return result;
@@ -597,7 +594,7 @@ static int __init pcc_cpufreq_init(void)
 
         ret = pcc_cpufreq_probe();
         if (ret) {
-                dprintk("pcc_cpufreq_init: PCCH evaluation failed\n");
+                pr_debug("pcc_cpufreq_init: PCCH evaluation failed\n");
                 return ret;
         }