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Diffstat (limited to 'drivers/cpufreq/qcom-cpufreq-kryo.c')
-rw-r--r--drivers/cpufreq/qcom-cpufreq-kryo.c212
1 files changed, 212 insertions, 0 deletions
diff --git a/drivers/cpufreq/qcom-cpufreq-kryo.c b/drivers/cpufreq/qcom-cpufreq-kryo.c
new file mode 100644
index 0000000000000..d049fe4b80c48
--- /dev/null
+++ b/drivers/cpufreq/qcom-cpufreq-kryo.c
@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ */
+
+/*
+ * In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors,
+ * the CPU frequency subset and voltage value of each OPP varies
+ * based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables
+ * defines the voltage and frequency value based on the msm-id in SMEM
+ * and speedbin blown in the efuse combination.
+ * The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the SoC
+ * to provide the OPP framework with required information.
+ * This is used to determine the voltage and frequency value for each OPP of
+ * operating-points-v2 table when it is parsed by the OPP framework.
+ */
+
+#include <linux/cpu.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/slab.h>
+#include <linux/soc/qcom/smem.h>
+
+#define MSM_ID_SMEM 137
+
+enum _msm_id {
+ MSM8996V3 = 0xF6ul,
+ APQ8096V3 = 0x123ul,
+ MSM8996SG = 0x131ul,
+ APQ8096SG = 0x138ul,
+};
+
+enum _msm8996_version {
+ MSM8996_V3,
+ MSM8996_SG,
+ NUM_OF_MSM8996_VERSIONS,
+};
+
+static enum _msm8996_version __init qcom_cpufreq_kryo_get_msm_id(void)
+{
+ size_t len;
+ u32 *msm_id;
+ enum _msm8996_version version;
+
+ msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, MSM_ID_SMEM, &len);
+ if (IS_ERR(msm_id))
+ return NUM_OF_MSM8996_VERSIONS;
+
+ /* The first 4 bytes are format, next to them is the actual msm-id */
+ msm_id++;
+
+ switch ((enum _msm_id)*msm_id) {
+ case MSM8996V3:
+ case APQ8096V3:
+ version = MSM8996_V3;
+ break;
+ case MSM8996SG:
+ case APQ8096SG:
+ version = MSM8996_SG;
+ break;
+ default:
+ version = NUM_OF_MSM8996_VERSIONS;
+ }
+
+ return version;
+}
+
+static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
+{
+ struct opp_table *opp_tables[NR_CPUS] = {0};
+ struct platform_device *cpufreq_dt_pdev;
+ enum _msm8996_version msm8996_version;
+ struct nvmem_cell *speedbin_nvmem;
+ struct device_node *np;
+ struct device *cpu_dev;
+ unsigned cpu;
+ u8 *speedbin;
+ u32 versions;
+ size_t len;
+ int ret;
+
+ cpu_dev = get_cpu_device(0);
+ if (NULL == cpu_dev)
+ ret = -ENODEV;
+
+ msm8996_version = qcom_cpufreq_kryo_get_msm_id();
+ if (NUM_OF_MSM8996_VERSIONS == msm8996_version) {
+ dev_err(cpu_dev, "Not Snapdragon 820/821!");
+ return -ENODEV;
+ }
+
+ np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
+ if (IS_ERR(np))
+ return PTR_ERR(np);
+
+ ret = of_device_is_compatible(np, "operating-points-v2-kryo-cpu");
+ if (!ret) {
+ of_node_put(np);
+ return -ENOENT;
+ }
+
+ speedbin_nvmem = of_nvmem_cell_get(np, NULL);
+ of_node_put(np);
+ if (IS_ERR(speedbin_nvmem)) {
+ dev_err(cpu_dev, "Could not get nvmem cell: %ld\n",
+ PTR_ERR(speedbin_nvmem));
+ return PTR_ERR(speedbin_nvmem);
+ }
+
+ speedbin = nvmem_cell_read(speedbin_nvmem, &len);
+ nvmem_cell_put(speedbin_nvmem);
+
+ switch (msm8996_version) {
+ case MSM8996_V3:
+ versions = 1 << (unsigned int)(*speedbin);
+ break;
+ case MSM8996_SG:
+ versions = 1 << ((unsigned int)(*speedbin) + 4);
+ break;
+ default:
+ BUG();
+ break;
+ }
+
+ for_each_possible_cpu(cpu) {
+ cpu_dev = get_cpu_device(cpu);
+ if (NULL == cpu_dev) {
+ ret = -ENODEV;
+ goto free_opp;
+ }
+
+ opp_tables[cpu] = dev_pm_opp_set_supported_hw(cpu_dev,
+ &versions, 1);
+ if (IS_ERR(opp_tables[cpu])) {
+ ret = PTR_ERR(opp_tables[cpu]);
+ dev_err(cpu_dev, "Failed to set supported hardware\n");
+ goto free_opp;
+ }
+ }
+
+ cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1,
+ NULL, 0);
+ if (!IS_ERR(cpufreq_dt_pdev))
+ return 0;
+
+ ret = PTR_ERR(cpufreq_dt_pdev);
+ dev_err(cpu_dev, "Failed to register platform device\n");
+
+free_opp:
+ for_each_possible_cpu(cpu) {
+ if (IS_ERR_OR_NULL(opp_tables[cpu]))
+ break;
+ dev_pm_opp_put_supported_hw(opp_tables[cpu]);
+ }
+
+ return ret;
+}
+
+static struct platform_driver qcom_cpufreq_kryo_driver = {
+ .probe = qcom_cpufreq_kryo_probe,
+ .driver = {
+ .name = "qcom-cpufreq-kryo",
+ },
+};
+
+static const struct of_device_id qcom_cpufreq_kryo_match_list[] __initconst = {
+ { .compatible = "qcom,apq8096", },
+ { .compatible = "qcom,msm8996", },
+};
+
+/*
+ * Since the driver depends on smem and nvmem drivers, which may
+ * return EPROBE_DEFER, all the real activity is done in the probe,
+ * which may be defered as well. The init here is only registering
+ * the driver and the platform device.
+ */
+static int __init qcom_cpufreq_kryo_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(qcom_cpufreq_kryo_match_list, np);
+ of_node_put(np);
+ if (!match)
+ return -ENODEV;
+
+ ret = platform_driver_register(&qcom_cpufreq_kryo_driver);
+ if (unlikely(ret < 0))
+ return ret;
+
+ ret = PTR_ERR_OR_ZERO(platform_device_register_simple(
+ "qcom-cpufreq-kryo", -1, NULL, 0));
+ if (0 == ret)
+ return 0;
+
+ platform_driver_unregister(&qcom_cpufreq_kryo_driver);
+ return ret;
+}
+module_init(qcom_cpufreq_kryo_init);
+
+MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Kryo CPUfreq driver");
+MODULE_LICENSE("GPL v2");