Merge tag 'v4.17-rc4' into patchwork

Linux 4.17-rc4

* tag 'v4.17-rc4': (920 commits)
  Linux 4.17-rc4
  KVM: x86: remove APIC Timer periodic/oneshot spikes
  genksyms: fix typo in parse.tab.{c,h} generation rules
  kbuild: replace hardcoded bison in cmd_bison_h with $(YACC)
  gcc-plugins: fix build condition of SANCOV plugin
  MAINTAINERS: Update Kbuild entry with a few paths
  Revert "usb: host: ehci: Use dma_pool_zalloc()"
  platform/x86: Kconfig: Fix dell-laptop dependency chain.
  platform/x86: asus-wireless: Fix NULL pointer dereference
  arm64: vgic-v2: Fix proxying of cpuif access
  KVM: arm/arm64: vgic_init: Cleanup reference to process_maintenance
  KVM: arm64: Fix order of vcpu_write_sys_reg() arguments
  MAINTAINERS & files: Canonize the e-mails I use at files
  media: imx-media-csi: Fix inconsistent IS_ERR and PTR_ERR
  tools: power/acpi, revert to LD = gcc
  bdi: Fix oops in wb_workfn()
  RDMA/cma: Do not query GID during QP state transition to RTR
  IB/mlx4: Fix integer overflow when calculating optimal MTT size
  IB/hfi1: Fix memory leak in exception path in get_irq_affinity()
  IB/{hfi1, rdmavt}: Fix memory leak in hfi1_alloc_devdata() upon failure
  ...

1 files changed, 44 insertions, 2 deletions

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index bc5fc1630876..b15115a48775 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -126,6 +126,49 @@ static void cppc_cpufreq_stop_cpu(struct cpufreq_policy *policy)
 				cpu->perf_caps.lowest_perf, cpu_num, ret);
 }
 
+/*
+ * The PCC subspace describes the rate at which platform can accept commands
+ * on the shared PCC channel (including READs which do not count towards freq
+ * trasition requests), so ideally we need to use the PCC values as a fallback
+ * if we don't have a platform specific transition_delay_us
+ */
+#ifdef CONFIG_ARM64
+#include <asm/cputype.h>
+
+static unsigned int cppc_cpufreq_get_transition_delay_us(int cpu)
+{
+	unsigned long implementor = read_cpuid_implementor();
+	unsigned long part_num = read_cpuid_part_number();
+	unsigned int delay_us = 0;
+
+	switch (implementor) {
+	case ARM_CPU_IMP_QCOM:
+		switch (part_num) {
+		case QCOM_CPU_PART_FALKOR_V1:
+		case QCOM_CPU_PART_FALKOR:
+			delay_us = 10000;
+			break;
+		default:
+			delay_us = cppc_get_transition_latency(cpu) / NSEC_PER_USEC;
+			break;
+		}
+		break;
+	default:
+		delay_us = cppc_get_transition_latency(cpu) / NSEC_PER_USEC;
+		break;
+	}
+
+	return delay_us;
+}
+
+#else
+
+static unsigned int cppc_cpufreq_get_transition_delay_us(int cpu)
+{
+	return cppc_get_transition_latency(cpu) / NSEC_PER_USEC;
+}
+#endif
+
 static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
 {
 	struct cppc_cpudata *cpu;
@@ -162,8 +205,7 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
 		cpu->perf_caps.highest_perf;
 	policy->cpuinfo.max_freq = cppc_dmi_max_khz;
 
-	policy->transition_delay_us = cppc_get_transition_latency(cpu_num) /
-		NSEC_PER_USEC;
+	policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu_num);
 	policy->shared_type = cpu->shared_type;
 
 	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {