Patch "ARM: vexpress: Set-up shared OPP table instead of individual for each CPU" has been added to the 4.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ARM: vexpress: Set-up shared OPP table instead of individual for each CPU

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm-vexpress-set-up-shared-opp-table-instead-of-indi.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 5760010f47909e2ebfc00711c8f35eb40bab63cd
Author: Sudeep Holla <sudeep.holla@xxxxxxx>
Date:   Wed Nov 27 15:56:40 2019 +0000

    ARM: vexpress: Set-up shared OPP table instead of individual for each CPU
    
    [ Upstream commit 2a76352ad2cc6b78e58f737714879cc860903802 ]
    
    Currently we add individual copy of same OPP table for each CPU within
    the cluster. This is redundant and doesn't reflect the reality.
    
    We can't use core cpumask to set policy->cpus in ve_spc_cpufreq_init()
    anymore as it gets called via cpuhp_cpufreq_online()->cpufreq_online()
    ->cpufreq_driver->init() and the cpumask gets updated upon CPU hotplug
    operations. It also may cause issues when the vexpress_spc_cpufreq
    driver is built as a module.
    
    Since ve_spc_clk_init is built-in device initcall, we should be able to
    use the same topology_core_cpumask to set the opp sharing cpumask via
    dev_pm_opp_set_sharing_cpus and use the same later in the driver via
    dev_pm_opp_get_sharing_cpus.
    
    Cc: Liviu Dudau <liviu.dudau@xxxxxxx>
    Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
    Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
    Tested-by: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
    Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/arm/mach-vexpress/spc.c b/arch/arm/mach-vexpress/spc.c
index 5766ce2be32b..29eb945075e3 100644
--- a/arch/arm/mach-vexpress/spc.c
+++ b/arch/arm/mach-vexpress/spc.c
@@ -555,8 +555,9 @@ static struct clk *ve_spc_clk_register(struct device *cpu_dev)
 
 static int __init ve_spc_clk_init(void)
 {
-	int cpu;
+	int cpu, cluster;
 	struct clk *clk;
+	bool init_opp_table[MAX_CLUSTERS] = { false };
 
 	if (!info)
 		return 0; /* Continue only if SPC is initialised */
@@ -582,8 +583,17 @@ static int __init ve_spc_clk_init(void)
 			continue;
 		}
 
+		cluster = topology_physical_package_id(cpu_dev->id);
+		if (init_opp_table[cluster])
+			continue;
+
 		if (ve_init_opp_table(cpu_dev))
 			pr_warn("failed to initialise cpu%d opp table\n", cpu);
+		else if (dev_pm_opp_set_sharing_cpus(cpu_dev,
+			 topology_core_cpumask(cpu_dev->id)))
+			pr_warn("failed to mark OPPs shared for cpu%d\n", cpu);
+		else
+			init_opp_table[cluster] = true;
 	}
 
 	platform_device_register_simple("vexpress-spc-cpufreq", -1, NULL, 0);