perf/x86/rapl: Use standard Energy Unit for SPR Dram RAPL domain

Intel Xeon servers used to use a fixed energy resolution (15.3uj) for
Dram RAPL domain. But on SPR, Dram RAPL domain follows the standard
energy resolution as described in MSR_RAPL_POWER_UNIT.

Remove the SPR Dram energy unit quirk.

Fixes: bcfd218 ("perf/x86/rapl: Add support for Intel SPR platform")
Signed-off-by: Zhang Rui <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Kan Liang <[email protected]>
Tested-by: Wang Wendy <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

Author: zhang-rui

arch/x86/events/rapl.c

@@ -619,12 +619,8 @@ static int rapl_check_hw_unit(struct rapl_model *rm)
 	case RAPL_UNIT_QUIRK_INTEL_HSW:
 		rapl_hw_unit[PERF_RAPL_RAM] = 16;
 		break;
-	/*
-	 * SPR shares the same DRAM domain energy unit as HSW, plus it
-	 * also has a fixed energy unit for Psys domain.
-	 */
+	/* SPR uses a fixed energy unit for Psys domain. */
 	case RAPL_UNIT_QUIRK_INTEL_SPR:
-		rapl_hw_unit[PERF_RAPL_RAM] = 16;
 		rapl_hw_unit[PERF_RAPL_PSYS] = 0;
 		break;
 	default: