perf/x86/intel/uncore: Fix the scale of the IMC free-running events

The "MiB" result of the IMC free-running bandwidth events,
uncore_imc_free_running/read/ and uncore_imc_free_running/write/ are 16
times too small.

The "MiB" value equals the raw IMC free-running bandwidth counter value
times a "scale" which is inaccurate.

The IMC free-running bandwidth events should be incremented per 64B
cache line, not DWs (4 bytes). The "scale" should be 6.103515625e-5.
Fix the "scale" for both Snow Ridge and Ice Lake.

Fixes: 2b3b76b ("perf/x86/intel/uncore: Add Ice Lake server uncore support")
Fixes: ee49532 ("perf/x86/intel/uncore: Add IMC uncore support for Snow Ridge")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200928133240.12977-1-kan.liang@linux.intel.com

Author: Kan Liang

arch/x86/events/intel/uncore_snbep.c

@@ -4807,10 +4807,10 @@ static struct uncore_event_desc snr_uncore_imc_freerunning_events[] = {
 	INTEL_UNCORE_EVENT_DESC(dclk,		"event=0xff,umask=0x10"),
 
 	INTEL_UNCORE_EVENT_DESC(read,		"event=0xff,umask=0x20"),
-	INTEL_UNCORE_EVENT_DESC(read.scale,	"3.814697266e-6"),
+	INTEL_UNCORE_EVENT_DESC(read.scale,	"6.103515625e-5"),
 	INTEL_UNCORE_EVENT_DESC(read.unit,	"MiB"),
 	INTEL_UNCORE_EVENT_DESC(write,		"event=0xff,umask=0x21"),
-	INTEL_UNCORE_EVENT_DESC(write.scale,	"3.814697266e-6"),
+	INTEL_UNCORE_EVENT_DESC(write.scale,	"6.103515625e-5"),
 	INTEL_UNCORE_EVENT_DESC(write.unit,	"MiB"),
 	{ /* end: all zeroes */ },
 };
@@ -5268,17 +5268,17 @@ static struct uncore_event_desc icx_uncore_imc_freerunning_events[] = {
 	INTEL_UNCORE_EVENT_DESC(dclk,			"event=0xff,umask=0x10"),
 
 	INTEL_UNCORE_EVENT_DESC(read,			"event=0xff,umask=0x20"),
-	INTEL_UNCORE_EVENT_DESC(read.scale,		"3.814697266e-6"),
+	INTEL_UNCORE_EVENT_DESC(read.scale,		"6.103515625e-5"),
 	INTEL_UNCORE_EVENT_DESC(read.unit,		"MiB"),
 	INTEL_UNCORE_EVENT_DESC(write,			"event=0xff,umask=0x21"),
-	INTEL_UNCORE_EVENT_DESC(write.scale,		"3.814697266e-6"),
+	INTEL_UNCORE_EVENT_DESC(write.scale,		"6.103515625e-5"),
 	INTEL_UNCORE_EVENT_DESC(write.unit,		"MiB"),
 
 	INTEL_UNCORE_EVENT_DESC(ddrt_read,		"event=0xff,umask=0x30"),
-	INTEL_UNCORE_EVENT_DESC(ddrt_read.scale,	"3.814697266e-6"),
+	INTEL_UNCORE_EVENT_DESC(ddrt_read.scale,	"6.103515625e-5"),
 	INTEL_UNCORE_EVENT_DESC(ddrt_read.unit,		"MiB"),
 	INTEL_UNCORE_EVENT_DESC(ddrt_write,		"event=0xff,umask=0x31"),
-	INTEL_UNCORE_EVENT_DESC(ddrt_write.scale,	"3.814697266e-6"),
+	INTEL_UNCORE_EVENT_DESC(ddrt_write.scale,	"6.103515625e-5"),
 	INTEL_UNCORE_EVENT_DESC(ddrt_write.unit,	"MiB"),
 	{ /* end: all zeroes */ },
 };