tegra186-cpufreq.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2017, NVIDIA CORPORATION. All rights reserved
*/
#include <linux/cpufreq.h>
#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <soc/tegra/bpmp.h>
#include <soc/tegra/bpmp-abi.h>
#define TEGRA186_NUM_CLUSTERS 2
#define EDVD_OFFSET_A57(core) ((SZ_64K * 6) + (0x20 + (core) * 0x4))
#define EDVD_OFFSET_DENVER(core) ((SZ_64K * 7) + (0x20 + (core) * 0x4))
#define EDVD_CORE_VOLT_FREQ_F_SHIFT 0
#define EDVD_CORE_VOLT_FREQ_F_MASK 0xffff
#define EDVD_CORE_VOLT_FREQ_V_SHIFT 16
struct tegra186_cpufreq_cpu {
unsigned int bpmp_cluster_id;
unsigned int edvd_offset;
};
static const struct tegra186_cpufreq_cpu tegra186_cpus[] = {
/* CPU0 - A57 Cluster */
{
.bpmp_cluster_id = 1,
.edvd_offset = EDVD_OFFSET_A57(0)
},
/* CPU1 - Denver Cluster */
{
.bpmp_cluster_id = 0,
.edvd_offset = EDVD_OFFSET_DENVER(0)
},
/* CPU2 - Denver Cluster */
{
.bpmp_cluster_id = 0,
.edvd_offset = EDVD_OFFSET_DENVER(1)
},
/* CPU3 - A57 Cluster */
{
.bpmp_cluster_id = 1,
.edvd_offset = EDVD_OFFSET_A57(1)
},
/* CPU4 - A57 Cluster */
{
.bpmp_cluster_id = 1,
.edvd_offset = EDVD_OFFSET_A57(2)
},
/* CPU5 - A57 Cluster */
{
.bpmp_cluster_id = 1,
.edvd_offset = EDVD_OFFSET_A57(3)
},
};
struct tegra186_cpufreq_cluster {
struct cpufreq_frequency_table *table;
u32 ref_clk_khz;
u32 div;
};
struct tegra186_cpufreq_data {
void __iomem *regs;
struct tegra186_cpufreq_cluster *clusters;
const struct tegra186_cpufreq_cpu *cpus;
};
static int tegra186_cpufreq_init(struct cpufreq_policy *policy)
{
struct tegra186_cpufreq_data *data = cpufreq_get_driver_data();
unsigned int cluster = data->cpus[policy->cpu].bpmp_cluster_id;
policy->freq_table = data->clusters[cluster].table;
policy->cpuinfo.transition_latency = 300 * 1000;
policy->driver_data = NULL;
return 0;
}
static int tegra186_cpufreq_set_target(struct cpufreq_policy *policy,
unsigned int index)
{
struct tegra186_cpufreq_data *data = cpufreq_get_driver_data();
struct cpufreq_frequency_table *tbl = policy->freq_table + index;
unsigned int edvd_offset = data->cpus[policy->cpu].edvd_offset;
u32 edvd_val = tbl->driver_data;
writel(edvd_val, data->regs + edvd_offset);
return 0;
}
static unsigned int tegra186_cpufreq_get(unsigned int cpu)
{
struct tegra186_cpufreq_data *data = cpufreq_get_driver_data();
struct tegra186_cpufreq_cluster *cluster;
struct cpufreq_policy *policy;
unsigned int edvd_offset, cluster_id;
u32 ndiv;
policy = cpufreq_cpu_get(cpu);
if (!policy)
return 0;
edvd_offset = data->cpus[policy->cpu].edvd_offset;
ndiv = readl(data->regs + edvd_offset) & EDVD_CORE_VOLT_FREQ_F_MASK;
cluster_id = data->cpus[policy->cpu].bpmp_cluster_id;
cluster = &data->clusters[cluster_id];
cpufreq_cpu_put(policy);
return (cluster->ref_clk_khz * ndiv) / cluster->div;
}
static struct cpufreq_driver tegra186_cpufreq_driver = {
.name = "tegra186",
.flags = CPUFREQ_STICKY | CPUFREQ_HAVE_GOVERNOR_PER_POLICY |
CPUFREQ_NEED_INITIAL_FREQ_CHECK,
.get = tegra186_cpufreq_get,
.verify = cpufreq_generic_frequency_table_verify,
.target_index = tegra186_cpufreq_set_target,
.init = tegra186_cpufreq_init,
.attr = cpufreq_generic_attr,
};
static struct cpufreq_frequency_table *init_vhint_table(
struct platform_device *pdev, struct tegra_bpmp *bpmp,
struct tegra186_cpufreq_cluster *cluster, unsigned int cluster_id)
{
struct cpufreq_frequency_table *table;
struct mrq_cpu_vhint_request req;
struct tegra_bpmp_message msg;
struct cpu_vhint_data *data;
int err, i, j, num_rates = 0;
dma_addr_t phys;
void *virt;
virt = dma_alloc_coherent(bpmp->dev, sizeof(*data), &phys,
GFP_KERNEL);
if (!virt)
return ERR_PTR(-ENOMEM);
data = (struct cpu_vhint_data *)virt;
memset(&req, 0, sizeof(req));
req.addr = phys;
req.cluster_id = cluster_id;
memset(&msg, 0, sizeof(msg));
msg.mrq = MRQ_CPU_VHINT;
msg.tx.data = &req;
msg.tx.size = sizeof(req);
err = tegra_bpmp_transfer(bpmp, &msg);
if (err) {
table = ERR_PTR(err);
goto free;
}
for (i = data->vfloor; i <= data->vceil; i++) {
u16 ndiv = data->ndiv[i];
if (ndiv < data->ndiv_min || ndiv > data->ndiv_max)
continue;
/* Only store lowest voltage index for each rate */
if (i > 0 && ndiv == data->ndiv[i - 1])
continue;
num_rates++;
}
table = devm_kcalloc(&pdev->dev, num_rates + 1, sizeof(*table),
GFP_KERNEL);
if (!table) {
table = ERR_PTR(-ENOMEM);
goto free;
}
cluster->ref_clk_khz = data->ref_clk_hz / 1000;
cluster->div = data->pdiv * data->mdiv;
for (i = data->vfloor, j = 0; i <= data->vceil; i++) {
struct cpufreq_frequency_table *point;
u16 ndiv = data->ndiv[i];
u32 edvd_val = 0;
if (ndiv < data->ndiv_min || ndiv > data->ndiv_max)
continue;
/* Only store lowest voltage index for each rate */
if (i > 0 && ndiv == data->ndiv[i - 1])
continue;
edvd_val |= i << EDVD_CORE_VOLT_FREQ_V_SHIFT;
edvd_val |= ndiv << EDVD_CORE_VOLT_FREQ_F_SHIFT;
point = &table[j++];
point->driver_data = edvd_val;
point->frequency = (cluster->ref_clk_khz * ndiv) / cluster->div;
}
table[j].frequency = CPUFREQ_TABLE_END;
free:
dma_free_coherent(bpmp->dev, sizeof(*data), virt, phys);
return table;
}
static int tegra186_cpufreq_probe(struct platform_device *pdev)
{
struct tegra186_cpufreq_data *data;
struct tegra_bpmp *bpmp;
unsigned int i = 0, err;
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->clusters = devm_kcalloc(&pdev->dev, TEGRA186_NUM_CLUSTERS,
sizeof(*data->clusters), GFP_KERNEL);
if (!data->clusters)
return -ENOMEM;
data->cpus = tegra186_cpus;
bpmp = tegra_bpmp_get(&pdev->dev);
if (IS_ERR(bpmp))
return PTR_ERR(bpmp);
data->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(data->regs)) {
err = PTR_ERR(data->regs);
goto put_bpmp;
}
for (i = 0; i < TEGRA186_NUM_CLUSTERS; i++) {
struct tegra186_cpufreq_cluster *cluster = &data->clusters[i];
cluster->table = init_vhint_table(pdev, bpmp, cluster, i);
if (IS_ERR(cluster->table)) {
err = PTR_ERR(cluster->table);
goto put_bpmp;
}
}
tegra186_cpufreq_driver.driver_data = data;
err = cpufreq_register_driver(&tegra186_cpufreq_driver);
put_bpmp:
tegra_bpmp_put(bpmp);
return err;
}
static int tegra186_cpufreq_remove(struct platform_device *pdev)
{
cpufreq_unregister_driver(&tegra186_cpufreq_driver);
return 0;
}
static const struct of_device_id tegra186_cpufreq_of_match[] = {
{ .compatible = "nvidia,tegra186-ccplex-cluster", },
{ }
};
MODULE_DEVICE_TABLE(of, tegra186_cpufreq_of_match);
static struct platform_driver tegra186_cpufreq_platform_driver = {
.driver = {
.name = "tegra186-cpufreq",
.of_match_table = tegra186_cpufreq_of_match,
},
.probe = tegra186_cpufreq_probe,
.remove = tegra186_cpufreq_remove,
};
module_platform_driver(tegra186_cpufreq_platform_driver);
MODULE_AUTHOR("Mikko Perttunen <mperttunen@nvidia.com>");
MODULE_DESCRIPTION("NVIDIA Tegra186 cpufreq driver");
MODULE_LICENSE("GPL v2");