cpufreq: airoha: Add EN7581 CPUFreq SMCCC driver

Add simple CPU Freq driver for Airoha EN7581 SoC that control CPU
frequency scaling with SMC APIs and register a generic "cpufreq-dt"
device.

All CPU share the same frequency and can't be controlled independently.
CPU frequency is controlled by the attached PM domain.

Add SoC compatible to cpufreq-dt-plat block list as a dedicated cpufreq
driver is needed with OPP v2 nodes declared in DTS.

Signed-off-by: Christian Marangi <[email protected]>
Signed-off-by: Viresh Kumar <[email protected]>

diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index 5f7e13e60c8023f6050bd2900999d12c041bc74b..704e84d0063906581f8117f0e526481139d4ae6d 100644 (file)
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -15,6 +15,14 @@ config ARM_ALLWINNER_SUN50I_CPUFREQ_NVMEM
          To compile this driver as a module, choose M here: the
          module will be called sun50i-cpufreq-nvmem.
 
+config ARM_AIROHA_SOC_CPUFREQ
+       tristate "Airoha EN7581 SoC CPUFreq support"
+       depends on ARCH_AIROHA || COMPILE_TEST
+       select PM_OPP
+       default ARCH_AIROHA
+       help
+         This adds the CPUFreq driver for Airoha EN7581 SoCs.
+
 config ARM_APPLE_SOC_CPUFREQ
        tristate "Apple Silicon SoC CPUFreq support"
        depends on ARCH_APPLE || (COMPILE_TEST && 64BIT)

diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index d35a28dd9463079693cdf58a3cb2343713dc8b0f..890fff99f37d94dc424a608798e4a2c283e9e8e4 100644 (file)
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -53,6 +53,7 @@ obj-$(CONFIG_X86_AMD_FREQ_SENSITIVITY)        += amd_freq_sensitivity.o
 
 ##################################################################################
 # ARM SoC drivers
+obj-$(CONFIG_ARM_AIROHA_SOC_CPUFREQ)   += airoha-cpufreq.o
 obj-$(CONFIG_ARM_APPLE_SOC_CPUFREQ)    += apple-soc-cpufreq.o
 obj-$(CONFIG_ARM_ARMADA_37XX_CPUFREQ)  += armada-37xx-cpufreq.o
 obj-$(CONFIG_ARM_ARMADA_8K_CPUFREQ)    += armada-8k-cpufreq.o

diff --git a/drivers/cpufreq/airoha-cpufreq.c b/drivers/cpufreq/airoha-cpufreq.c
new file mode 100644 (file)
index 0000000..4fe39ea
--- /dev/null
+++ b/drivers/cpufreq/airoha-cpufreq.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bitfield.h>
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+
+#include "cpufreq-dt.h"
+
+struct airoha_cpufreq_priv {
+       int opp_token;
+       struct dev_pm_domain_list *pd_list;
+       struct platform_device *cpufreq_dt;
+};
+
+static struct platform_device *cpufreq_pdev;
+
+/* NOP function to disable OPP from setting clock */
+static int airoha_cpufreq_config_clks_nop(struct device *dev,
+                                         struct opp_table *opp_table,
+                                         struct dev_pm_opp *opp,
+                                         void *data, bool scaling_down)
+{
+       return 0;
+}
+
+static const char * const airoha_cpufreq_clk_names[] = { "cpu", NULL };
+static const char * const airoha_cpufreq_pd_names[] = { "perf" };
+
+static int airoha_cpufreq_probe(struct platform_device *pdev)
+{
+       const struct dev_pm_domain_attach_data attach_data = {
+               .pd_names = airoha_cpufreq_pd_names,
+               .num_pd_names = ARRAY_SIZE(airoha_cpufreq_pd_names),
+               .pd_flags = PD_FLAG_DEV_LINK_ON | PD_FLAG_REQUIRED_OPP,
+       };
+       struct dev_pm_opp_config config = {
+               .clk_names = airoha_cpufreq_clk_names,
+               .config_clks = airoha_cpufreq_config_clks_nop,
+       };
+       struct platform_device *cpufreq_dt;
+       struct airoha_cpufreq_priv *priv;
+       struct device *dev = &pdev->dev;
+       struct device *cpu_dev;
+       int ret;
+
+       /* CPUs refer to the same OPP table */
+       cpu_dev = get_cpu_device(0);
+       if (!cpu_dev)
+               return -ENODEV;
+
+       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       /* Set OPP table conf with NOP config_clks */
+       priv->opp_token = dev_pm_opp_set_config(cpu_dev, &config);
+       if (priv->opp_token < 0)
+               return dev_err_probe(dev, priv->opp_token, "Failed to set OPP config\n");
+
+       /* Attach PM for OPP */
+       ret = dev_pm_domain_attach_list(cpu_dev, &attach_data,
+                                       &priv->pd_list);
+       if (ret)
+               goto clear_opp_config;
+
+       cpufreq_dt = platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
+       ret = PTR_ERR_OR_ZERO(cpufreq_dt);
+       if (ret) {
+               dev_err(dev, "failed to create cpufreq-dt device: %d\n", ret);
+               goto detach_pm;
+       }
+
+       priv->cpufreq_dt = cpufreq_dt;
+       platform_set_drvdata(pdev, priv);
+
+       return 0;
+
+detach_pm:
+       dev_pm_domain_detach_list(priv->pd_list);
+clear_opp_config:
+       dev_pm_opp_clear_config(priv->opp_token);
+
+       return ret;
+}
+
+static void airoha_cpufreq_remove(struct platform_device *pdev)
+{
+       struct airoha_cpufreq_priv *priv = platform_get_drvdata(pdev);
+
+       platform_device_unregister(priv->cpufreq_dt);
+
+       dev_pm_domain_detach_list(priv->pd_list);
+
+       dev_pm_opp_clear_config(priv->opp_token);
+}
+
+static struct platform_driver airoha_cpufreq_driver = {
+       .probe = airoha_cpufreq_probe,
+       .remove = airoha_cpufreq_remove,
+       .driver = {
+               .name = "airoha-cpufreq",
+       },
+};
+
+static const struct of_device_id airoha_cpufreq_match_list[] __initconst = {
+       { .compatible = "airoha,en7581" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, airoha_cpufreq_match_list);
+
+static int __init airoha_cpufreq_init(void)
+{
+       struct device_node *np = of_find_node_by_path("/");
+       const struct of_device_id *match;
+       int ret;
+
+       if (!np)
+               return -ENODEV;
+
+       match = of_match_node(airoha_cpufreq_match_list, np);
+       of_node_put(np);
+       if (!match)
+               return -ENODEV;
+
+       ret = platform_driver_register(&airoha_cpufreq_driver);
+       if (unlikely(ret < 0))
+               return ret;
+
+       cpufreq_pdev = platform_device_register_data(NULL, "airoha-cpufreq",
+                                                    -1, match, sizeof(*match));
+       ret = PTR_ERR_OR_ZERO(cpufreq_pdev);
+       if (ret)
+               platform_driver_unregister(&airoha_cpufreq_driver);
+
+       return ret;
+}
+module_init(airoha_cpufreq_init);
+
+static void __exit airoha_cpufreq_exit(void)
+{
+       platform_device_unregister(cpufreq_pdev);
+       platform_driver_unregister(&airoha_cpufreq_driver);
+}
+module_exit(airoha_cpufreq_exit);
+
+MODULE_AUTHOR("Christian Marangi <[email protected]>");
+MODULE_DESCRIPTION("CPUfreq driver for Airoha SoCs");
+MODULE_LICENSE("GPL");

diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c
index 9c198bd4f7e9b2fa174b1bc7f8c3e10dc735ea01..2aa00769cf09dab20ae1cc4f7c0fe4fb6d22af87 100644 (file)
--- a/drivers/cpufreq/cpufreq-dt-platdev.c
+++ b/drivers/cpufreq/cpufreq-dt-platdev.c
@@ -103,6 +103,8 @@ static const struct of_device_id allowlist[] __initconst = {
  * platforms using "operating-points-v2" property.
  */
 static const struct of_device_id blocklist[] __initconst = {
+       { .compatible = "airoha,en7581", },
+
        { .compatible = "allwinner,sun50i-a100" },
        { .compatible = "allwinner,sun50i-h6", },
        { .compatible = "allwinner,sun50i-h616", },