This patch set adds below improvements to the Tegra194 CPUFREQ driver.
They are applicable to all the Tegra SoC's supported by the driver.
1) Patch 1: Avoid making SMP call on every frequency request to reduce
the time for frequency set and get calls.
2) Patch 2: Use reference clock count based loop instead of udelay()
to improve the accuracy of re-generated CPU frequency.
The patches are not related but have minor conflict. So, need to be
applied in order of patch numbers. If 'Patch 2' is to be applied first
then will rebase that and send separately.
---
v1[2] -> v3:
- Patch 1: used sizeof(*data->cpu_data) in devm_kcalloc().
v1[1] -> v2:
- Patch 1: added new patch.
- Patch 2: changed subject and patch order.
Sumit Gupta (2):
cpufreq: tegra194: save CPU data to avoid repeated SMP calls
cpufreq: tegra194: use refclk delta based loop instead of udelay
drivers/cpufreq/tegra194-cpufreq.c | 151 ++++++++++++++++++++---------
1 file changed, 106 insertions(+), 45 deletions(-)
[2] https://lore.kernel.org/lkml/[email protected]/
[1] https://lore.kernel.org/lkml/[email protected]/
--
2.17.1
Currently, we make SMP call on every frequency set request to get the
physical 'CPU ID' and 'CLUSTER ID' for the target CPU. This change
optimizes the repeated calls by storing the physical IDs and the per
core frequency register offset for all CPUs during boot. Later this
info is used directly when required to set the frequency or read it
from ACTMON counters.
Signed-off-by: Sumit Gupta <[email protected]>
---
drivers/cpufreq/tegra194-cpufreq.c | 79 +++++++++++++++++++-----------
1 file changed, 51 insertions(+), 28 deletions(-)
diff --git a/drivers/cpufreq/tegra194-cpufreq.c b/drivers/cpufreq/tegra194-cpufreq.c
index 386aed3637b4..f6a8e6cf6d94 100644
--- a/drivers/cpufreq/tegra194-cpufreq.c
+++ b/drivers/cpufreq/tegra194-cpufreq.c
@@ -39,6 +39,12 @@
/* cpufreq transisition latency */
#define TEGRA_CPUFREQ_TRANSITION_LATENCY (300 * 1000) /* unit in nanoseconds */
+struct tegra_cpu_data {
+ u32 cpuid;
+ u32 clusterid;
+ void __iomem *freq_core_reg;
+};
+
struct tegra_cpu_ctr {
u32 cpu;
u32 coreclk_cnt, last_coreclk_cnt;
@@ -69,6 +75,7 @@ struct tegra194_cpufreq_data {
struct cpufreq_frequency_table **bpmp_luts;
const struct tegra_cpufreq_soc *soc;
bool icc_dram_bw_scaling;
+ struct tegra_cpu_data *cpu_data;
};
static struct workqueue_struct *read_counters_wq;
@@ -116,14 +123,8 @@ static void tegra234_get_cpu_cluster_id(u32 cpu, u32 *cpuid, u32 *clusterid)
static int tegra234_get_cpu_ndiv(u32 cpu, u32 cpuid, u32 clusterid, u64 *ndiv)
{
struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
- void __iomem *freq_core_reg;
- u64 mpidr_id;
-
- /* use physical id to get address of per core frequency register */
- mpidr_id = (clusterid * data->soc->maxcpus_per_cluster) + cpuid;
- freq_core_reg = SCRATCH_FREQ_CORE_REG(data, mpidr_id);
- *ndiv = readl(freq_core_reg) & NDIV_MASK;
+ *ndiv = readl(data->cpu_data[cpu].freq_core_reg) & NDIV_MASK;
return 0;
}
@@ -131,19 +132,10 @@ static int tegra234_get_cpu_ndiv(u32 cpu, u32 cpuid, u32 clusterid, u64 *ndiv)
static void tegra234_set_cpu_ndiv(struct cpufreq_policy *policy, u64 ndiv)
{
struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
- void __iomem *freq_core_reg;
- u32 cpu, cpuid, clusterid;
- u64 mpidr_id;
-
- for_each_cpu_and(cpu, policy->cpus, cpu_online_mask) {
- data->soc->ops->get_cpu_cluster_id(cpu, &cpuid, &clusterid);
-
- /* use physical id to get address of per core frequency register */
- mpidr_id = (clusterid * data->soc->maxcpus_per_cluster) + cpuid;
- freq_core_reg = SCRATCH_FREQ_CORE_REG(data, mpidr_id);
+ u32 cpu;
- writel(ndiv, freq_core_reg);
- }
+ for_each_cpu_and(cpu, policy->cpus, cpu_online_mask)
+ writel(ndiv, data->cpu_data[cpu].freq_core_reg);
}
/*
@@ -157,11 +149,10 @@ static void tegra234_read_counters(struct tegra_cpu_ctr *c)
{
struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
void __iomem *actmon_reg;
- u32 cpuid, clusterid;
u64 val;
- data->soc->ops->get_cpu_cluster_id(c->cpu, &cpuid, &clusterid);
- actmon_reg = CORE_ACTMON_CNTR_REG(data, clusterid, cpuid);
+ actmon_reg = CORE_ACTMON_CNTR_REG(data, data->cpu_data[c->cpu].clusterid,
+ data->cpu_data[c->cpu].cpuid);
val = readq(actmon_reg);
c->last_refclk_cnt = upper_32_bits(val);
@@ -357,19 +348,17 @@ static void tegra194_set_cpu_ndiv(struct cpufreq_policy *policy, u64 ndiv)
static unsigned int tegra194_get_speed(u32 cpu)
{
struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
+ u32 clusterid = data->cpu_data[cpu].clusterid;
struct cpufreq_frequency_table *pos;
- u32 cpuid, clusterid;
unsigned int rate;
u64 ndiv;
int ret;
- data->soc->ops->get_cpu_cluster_id(cpu, &cpuid, &clusterid);
-
/* reconstruct actual cpu freq using counters */
rate = tegra194_calculate_speed(cpu);
/* get last written ndiv value */
- ret = data->soc->ops->get_cpu_ndiv(cpu, cpuid, clusterid, &ndiv);
+ ret = data->soc->ops->get_cpu_ndiv(cpu, data->cpu_data[cpu].cpuid, clusterid, &ndiv);
if (WARN_ON_ONCE(ret))
return rate;
@@ -475,13 +464,12 @@ static int tegra194_cpufreq_init(struct cpufreq_policy *policy)
{
struct tegra194_cpufreq_data *data = cpufreq_get_driver_data();
int maxcpus_per_cluster = data->soc->maxcpus_per_cluster;
+ u32 clusterid = data->cpu_data[policy->cpu].clusterid;
struct cpufreq_frequency_table *freq_table;
struct cpufreq_frequency_table *bpmp_lut;
u32 start_cpu, cpu;
- u32 clusterid;
int ret;
- data->soc->ops->get_cpu_cluster_id(policy->cpu, NULL, &clusterid);
if (clusterid >= data->soc->num_clusters || !data->bpmp_luts[clusterid])
return -EINVAL;
@@ -659,6 +647,28 @@ tegra_cpufreq_bpmp_read_lut(struct platform_device *pdev, struct tegra_bpmp *bpm
return freq_table;
}
+static int tegra194_cpufreq_store_physids(unsigned int cpu, struct tegra194_cpufreq_data *data)
+{
+ int num_cpus = data->soc->maxcpus_per_cluster * data->soc->num_clusters;
+ u32 cpuid, clusterid;
+ u64 mpidr_id;
+
+ if (cpu > (num_cpus - 1)) {
+ pr_err("cpufreq: wrong num of cpus or clusters in soc data\n");
+ return -EINVAL;
+ }
+
+ data->soc->ops->get_cpu_cluster_id(cpu, &cpuid, &clusterid);
+
+ mpidr_id = (clusterid * data->soc->maxcpus_per_cluster) + cpuid;
+
+ data->cpu_data[cpu].cpuid = cpuid;
+ data->cpu_data[cpu].clusterid = clusterid;
+ data->cpu_data[cpu].freq_core_reg = SCRATCH_FREQ_CORE_REG(data, mpidr_id);
+
+ return 0;
+}
+
static int tegra194_cpufreq_probe(struct platform_device *pdev)
{
const struct tegra_cpufreq_soc *soc;
@@ -666,6 +676,7 @@ static int tegra194_cpufreq_probe(struct platform_device *pdev)
struct tegra_bpmp *bpmp;
struct device *cpu_dev;
int err, i;
+ u32 cpu;
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
@@ -692,6 +703,12 @@ static int tegra194_cpufreq_probe(struct platform_device *pdev)
return PTR_ERR(data->regs);
}
+ data->cpu_data = devm_kcalloc(&pdev->dev, data->soc->num_clusters *
+ data->soc->maxcpus_per_cluster,
+ sizeof(*data->cpu_data), GFP_KERNEL);
+ if (!data->cpu_data)
+ return -ENOMEM;
+
platform_set_drvdata(pdev, data);
bpmp = tegra_bpmp_get(&pdev->dev);
@@ -713,6 +730,12 @@ static int tegra194_cpufreq_probe(struct platform_device *pdev)
}
}
+ for_each_possible_cpu(cpu) {
+ err = tegra194_cpufreq_store_physids(cpu, data);
+ if (err)
+ goto err_free_res;
+ }
+
tegra194_cpufreq_driver.driver_data = data;
/* Check for optional OPPv2 and interconnect paths on CPU0 to enable ICC scaling */
--
2.17.1
On 04/10/23 19:35, Sumit Gupta wrote:
> This patch set adds below improvements to the Tegra194 CPUFREQ driver.
> They are applicable to all the Tegra SoC's supported by the driver.
>
> 1) Patch 1: Avoid making SMP call on every frequency request to reduce
> the time for frequency set and get calls.
>
> 2) Patch 2: Use reference clock count based loop instead of udelay()
> to improve the accuracy of re-generated CPU frequency.
>
> The patches are not related but have minor conflict. So, need to be
> applied in order of patch numbers. If 'Patch 2' is to be applied first
> then will rebase that and send separately.
>
> ---
> v1[2] -> v3:
> - Patch 1: used sizeof(*data->cpu_data) in devm_kcalloc().
>
> v1[1] -> v2:
> - Patch 1: added new patch.
> - Patch 2: changed subject and patch order.
>
> Sumit Gupta (2):
> cpufreq: tegra194: save CPU data to avoid repeated SMP calls
> cpufreq: tegra194: use refclk delta based loop instead of udelay
>
> drivers/cpufreq/tegra194-cpufreq.c | 151 ++++++++++++++++++++---------
> 1 file changed, 106 insertions(+), 45 deletions(-)
>
> [2] https://lore.kernel.org/lkml/[email protected]/
> [1] https://lore.kernel.org/lkml/[email protected]/
>
Hi Viresh,
If there is no further comment.
Can we please still apply these patches for 6.7 ?
Best Regards,
Sumit Gupta
On 09-10-23, 17:06, Sumit Gupta wrote:
>
>
> On 04/10/23 19:35, Sumit Gupta wrote:
> > This patch set adds below improvements to the Tegra194 CPUFREQ driver.
> > They are applicable to all the Tegra SoC's supported by the driver.
> >
> > 1) Patch 1: Avoid making SMP call on every frequency request to reduce
> > the time for frequency set and get calls.
> >
> > 2) Patch 2: Use reference clock count based loop instead of udelay()
> > to improve the accuracy of re-generated CPU frequency.
> >
> > The patches are not related but have minor conflict. So, need to be
> > applied in order of patch numbers. If 'Patch 2' is to be applied first
> > then will rebase that and send separately.
> >
> > ---
> > v1[2] -> v3:
> > - Patch 1: used sizeof(*data->cpu_data) in devm_kcalloc().
> >
> > v1[1] -> v2:
> > - Patch 1: added new patch.
> > - Patch 2: changed subject and patch order.
> >
> > Sumit Gupta (2):
> > cpufreq: tegra194: save CPU data to avoid repeated SMP calls
> > cpufreq: tegra194: use refclk delta based loop instead of udelay
> >
> > drivers/cpufreq/tegra194-cpufreq.c | 151 ++++++++++++++++++++---------
> > 1 file changed, 106 insertions(+), 45 deletions(-)
> >
> > [2] https://lore.kernel.org/lkml/[email protected]/
> > [1] https://lore.kernel.org/lkml/[email protected]/
> >
>
> Hi Viresh,
>
> If there is no further comment.
> Can we please still apply these patches for 6.7 ?
Applied. Thanks.
FWIW, you should have rebased the other commit (which removes cpu
online mask) over this one. I had to fix the commit manually now.
--
viresh
On 10/10/23 11:07, Viresh Kumar wrote:
> External email: Use caution opening links or attachments
>
>
> On 09-10-23, 17:06, Sumit Gupta wrote:
>>
>>
>> On 04/10/23 19:35, Sumit Gupta wrote:
>>> This patch set adds below improvements to the Tegra194 CPUFREQ driver.
>>> They are applicable to all the Tegra SoC's supported by the driver.
>>>
>>> 1) Patch 1: Avoid making SMP call on every frequency request to reduce
>>> the time for frequency set and get calls.
>>>
>>> 2) Patch 2: Use reference clock count based loop instead of udelay()
>>> to improve the accuracy of re-generated CPU frequency.
>>>
>>> The patches are not related but have minor conflict. So, need to be
>>> applied in order of patch numbers. If 'Patch 2' is to be applied first
>>> then will rebase that and send separately.
>>>
>>> ---
>>> v1[2] -> v3:
>>> - Patch 1: used sizeof(*data->cpu_data) in devm_kcalloc().
>>>
>>> v1[1] -> v2:
>>> - Patch 1: added new patch.
>>> - Patch 2: changed subject and patch order.
>>>
>>> Sumit Gupta (2):
>>> cpufreq: tegra194: save CPU data to avoid repeated SMP calls
>>> cpufreq: tegra194: use refclk delta based loop instead of udelay
>>>
>>> drivers/cpufreq/tegra194-cpufreq.c | 151 ++++++++++++++++++++---------
>>> 1 file changed, 106 insertions(+), 45 deletions(-)
>>>
>>> [2] https://lore.kernel.org/lkml/[email protected]/
>>> [1] https://lore.kernel.org/lkml/[email protected]/
>>>
>>
>> Hi Viresh,
>>
>> If there is no further comment.
>> Can we please still apply these patches for 6.7 ?
>
> Applied. Thanks.
>
> FWIW, you should have rebased the other commit (which removes cpu
> online mask) over this one. I had to fix the commit manually now.
>
> --
> viresh
Sorry, my bad.
Thank you for your help.
Best Regards,
Sumit Gupta