[Patch] cpufreq: replace cpu_logical_map with read_cpuid_mpir

From: Sumit Gupta
Date: Tue Aug 11 2020 - 15:43:35 EST


Commit eaecca9e7710 ("arm64: Fix __cpu_logical_map undefined issue")
fixes the issue with building tegra194 cpufreq driver as module. But
the fix might cause problem while supporting physical cpu hotplug[1].

This patch fixes the original problem by avoiding use of cpu_logical_map().
Instead calling read_cpuid_mpidr() to get MPIDR on target cpu.

[1] https://lore.kernel.org/linux-arm-kernel/20200724131059.GB6521@bogus/

Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx>
Signed-off-by: Sumit Gupta <sumitg@xxxxxxxxxx>
---
drivers/cpufreq/tegra194-cpufreq.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/tegra194-cpufreq.c b/drivers/cpufreq/tegra194-cpufreq.c
index bae527e..e1d931c 100644
--- a/drivers/cpufreq/tegra194-cpufreq.c
+++ b/drivers/cpufreq/tegra194-cpufreq.c
@@ -56,9 +56,11 @@ struct read_counters_work {

static struct workqueue_struct *read_counters_wq;

-static enum cluster get_cpu_cluster(u8 cpu)
+static void get_cpu_cluster(void *cluster)
{
- return MPIDR_AFFINITY_LEVEL(cpu_logical_map(cpu), 1);
+ u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
+
+ *((uint32_t *)cluster) = MPIDR_AFFINITY_LEVEL(mpidr, 1);
}

/*
@@ -186,8 +188,10 @@ static unsigned int tegra194_get_speed(u32 cpu)
static int tegra194_cpufreq_init(struct cpufreq_policy *policy)
{
struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
- int cl = get_cpu_cluster(policy->cpu);
u32 cpu;
+ u32 cl;
+
+ smp_call_function_single(policy->cpu, get_cpu_cluster, &cl, true);

if (cl >= data->num_clusters)
return -EINVAL;
--
2.7.4