summaryrefslogtreecommitdiffstats
path: root/drivers/cpufreq/imx-cpufreq-dt.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/cpufreq/imx-cpufreq-dt.c')
-rw-r--r--drivers/cpufreq/imx-cpufreq-dt.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/drivers/cpufreq/imx-cpufreq-dt.c b/drivers/cpufreq/imx-cpufreq-dt.c
new file mode 100644
index 000000000..535867a7d
--- /dev/null
+++ b/drivers/cpufreq/imx-cpufreq-dt.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP
+ */
+
+#include <linux/clk.h>
+#include <linux/cpu.h>
+#include <linux/cpufreq.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#include "cpufreq-dt.h"
+
+#define OCOTP_CFG3_SPEED_GRADE_SHIFT 8
+#define OCOTP_CFG3_SPEED_GRADE_MASK (0x3 << 8)
+#define IMX8MN_OCOTP_CFG3_SPEED_GRADE_MASK (0xf << 8)
+#define OCOTP_CFG3_MKT_SEGMENT_SHIFT 6
+#define OCOTP_CFG3_MKT_SEGMENT_MASK (0x3 << 6)
+#define IMX8MP_OCOTP_CFG3_MKT_SEGMENT_SHIFT 5
+#define IMX8MP_OCOTP_CFG3_MKT_SEGMENT_MASK (0x3 << 5)
+
+#define IMX7ULP_MAX_RUN_FREQ 528000
+
+/* cpufreq-dt device registered by imx-cpufreq-dt */
+static struct platform_device *cpufreq_dt_pdev;
+static struct device *cpu_dev;
+static int cpufreq_opp_token;
+
+enum IMX7ULP_CPUFREQ_CLKS {
+ ARM,
+ CORE,
+ SCS_SEL,
+ HSRUN_CORE,
+ HSRUN_SCS_SEL,
+ FIRC,
+};
+
+static struct clk_bulk_data imx7ulp_clks[] = {
+ { .id = "arm" },
+ { .id = "core" },
+ { .id = "scs_sel" },
+ { .id = "hsrun_core" },
+ { .id = "hsrun_scs_sel" },
+ { .id = "firc" },
+};
+
+static unsigned int imx7ulp_get_intermediate(struct cpufreq_policy *policy,
+ unsigned int index)
+{
+ return clk_get_rate(imx7ulp_clks[FIRC].clk);
+}
+
+static int imx7ulp_target_intermediate(struct cpufreq_policy *policy,
+ unsigned int index)
+{
+ unsigned int newfreq = policy->freq_table[index].frequency;
+
+ clk_set_parent(imx7ulp_clks[SCS_SEL].clk, imx7ulp_clks[FIRC].clk);
+ clk_set_parent(imx7ulp_clks[HSRUN_SCS_SEL].clk, imx7ulp_clks[FIRC].clk);
+
+ if (newfreq > IMX7ULP_MAX_RUN_FREQ)
+ clk_set_parent(imx7ulp_clks[ARM].clk,
+ imx7ulp_clks[HSRUN_CORE].clk);
+ else
+ clk_set_parent(imx7ulp_clks[ARM].clk, imx7ulp_clks[CORE].clk);
+
+ return 0;
+}
+
+static struct cpufreq_dt_platform_data imx7ulp_data = {
+ .target_intermediate = imx7ulp_target_intermediate,
+ .get_intermediate = imx7ulp_get_intermediate,
+};
+
+static int imx_cpufreq_dt_probe(struct platform_device *pdev)
+{
+ struct platform_device *dt_pdev;
+ u32 cell_value, supported_hw[2];
+ int speed_grade, mkt_segment;
+ int ret;
+
+ cpu_dev = get_cpu_device(0);
+
+ if (!of_property_present(cpu_dev->of_node, "cpu-supply"))
+ return -ENODEV;
+
+ if (of_machine_is_compatible("fsl,imx7ulp")) {
+ ret = clk_bulk_get(cpu_dev, ARRAY_SIZE(imx7ulp_clks),
+ imx7ulp_clks);
+ if (ret)
+ return ret;
+
+ dt_pdev = platform_device_register_data(NULL, "cpufreq-dt",
+ -1, &imx7ulp_data,
+ sizeof(imx7ulp_data));
+ if (IS_ERR(dt_pdev)) {
+ clk_bulk_put(ARRAY_SIZE(imx7ulp_clks), imx7ulp_clks);
+ ret = PTR_ERR(dt_pdev);
+ dev_err(&pdev->dev, "Failed to register cpufreq-dt: %d\n", ret);
+ return ret;
+ }
+
+ cpufreq_dt_pdev = dt_pdev;
+
+ return 0;
+ }
+
+ ret = nvmem_cell_read_u32(cpu_dev, "speed_grade", &cell_value);
+ if (ret)
+ return ret;
+
+ if (of_machine_is_compatible("fsl,imx8mn") ||
+ of_machine_is_compatible("fsl,imx8mp"))
+ speed_grade = (cell_value & IMX8MN_OCOTP_CFG3_SPEED_GRADE_MASK)
+ >> OCOTP_CFG3_SPEED_GRADE_SHIFT;
+ else
+ speed_grade = (cell_value & OCOTP_CFG3_SPEED_GRADE_MASK)
+ >> OCOTP_CFG3_SPEED_GRADE_SHIFT;
+
+ if (of_machine_is_compatible("fsl,imx8mp"))
+ mkt_segment = (cell_value & IMX8MP_OCOTP_CFG3_MKT_SEGMENT_MASK)
+ >> IMX8MP_OCOTP_CFG3_MKT_SEGMENT_SHIFT;
+ else
+ mkt_segment = (cell_value & OCOTP_CFG3_MKT_SEGMENT_MASK)
+ >> OCOTP_CFG3_MKT_SEGMENT_SHIFT;
+
+ /*
+ * Early samples without fuses written report "0 0" which may NOT
+ * match any OPP defined in DT. So clamp to minimum OPP defined in
+ * DT to avoid warning for "no OPPs".
+ *
+ * Applies to i.MX8M series SoCs.
+ */
+ if (mkt_segment == 0 && speed_grade == 0) {
+ if (of_machine_is_compatible("fsl,imx8mm") ||
+ of_machine_is_compatible("fsl,imx8mq"))
+ speed_grade = 1;
+ if (of_machine_is_compatible("fsl,imx8mn") ||
+ of_machine_is_compatible("fsl,imx8mp"))
+ speed_grade = 0xb;
+ }
+
+ supported_hw[0] = BIT(speed_grade);
+ supported_hw[1] = BIT(mkt_segment);
+ dev_info(&pdev->dev, "cpu speed grade %d mkt segment %d supported-hw %#x %#x\n",
+ speed_grade, mkt_segment, supported_hw[0], supported_hw[1]);
+
+ cpufreq_opp_token = dev_pm_opp_set_supported_hw(cpu_dev, supported_hw, 2);
+ if (cpufreq_opp_token < 0) {
+ ret = cpufreq_opp_token;
+ dev_err(&pdev->dev, "Failed to set supported opp: %d\n", ret);
+ return ret;
+ }
+
+ cpufreq_dt_pdev = platform_device_register_data(
+ &pdev->dev, "cpufreq-dt", -1, NULL, 0);
+ if (IS_ERR(cpufreq_dt_pdev)) {
+ dev_pm_opp_put_supported_hw(cpufreq_opp_token);
+ ret = PTR_ERR(cpufreq_dt_pdev);
+ dev_err(&pdev->dev, "Failed to register cpufreq-dt: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int imx_cpufreq_dt_remove(struct platform_device *pdev)
+{
+ platform_device_unregister(cpufreq_dt_pdev);
+ if (!of_machine_is_compatible("fsl,imx7ulp"))
+ dev_pm_opp_put_supported_hw(cpufreq_opp_token);
+ else
+ clk_bulk_put(ARRAY_SIZE(imx7ulp_clks), imx7ulp_clks);
+
+ return 0;
+}
+
+static struct platform_driver imx_cpufreq_dt_driver = {
+ .probe = imx_cpufreq_dt_probe,
+ .remove = imx_cpufreq_dt_remove,
+ .driver = {
+ .name = "imx-cpufreq-dt",
+ },
+};
+module_platform_driver(imx_cpufreq_dt_driver);
+
+MODULE_ALIAS("platform:imx-cpufreq-dt");
+MODULE_DESCRIPTION("Freescale i.MX cpufreq speed grading driver");
+MODULE_LICENSE("GPL v2");