diff options
Diffstat (limited to 'drivers/cpufreq/ti-cpufreq.c')
-rw-r--r-- | drivers/cpufreq/ti-cpufreq.c | 425 |
1 files changed, 425 insertions, 0 deletions
diff --git a/drivers/cpufreq/ti-cpufreq.c b/drivers/cpufreq/ti-cpufreq.c new file mode 100644 index 000000000..f64180dd2 --- /dev/null +++ b/drivers/cpufreq/ti-cpufreq.c @@ -0,0 +1,425 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * TI CPUFreq/OPP hw-supported driver + * + * Copyright (C) 2016-2017 Texas Instruments, Inc. + * Dave Gerlach <d-gerlach@ti.com> + */ + +#include <linux/cpu.h> +#include <linux/io.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/pm_opp.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#define REVISION_MASK 0xF +#define REVISION_SHIFT 28 + +#define AM33XX_800M_ARM_MPU_MAX_FREQ 0x1E2F +#define AM43XX_600M_ARM_MPU_MAX_FREQ 0xFFA + +#define DRA7_EFUSE_HAS_OD_MPU_OPP 11 +#define DRA7_EFUSE_HAS_HIGH_MPU_OPP 15 +#define DRA76_EFUSE_HAS_PLUS_MPU_OPP 18 +#define DRA7_EFUSE_HAS_ALL_MPU_OPP 23 +#define DRA76_EFUSE_HAS_ALL_MPU_OPP 24 + +#define DRA7_EFUSE_NOM_MPU_OPP BIT(0) +#define DRA7_EFUSE_OD_MPU_OPP BIT(1) +#define DRA7_EFUSE_HIGH_MPU_OPP BIT(2) +#define DRA76_EFUSE_PLUS_MPU_OPP BIT(3) + +#define OMAP3_CONTROL_DEVICE_STATUS 0x4800244C +#define OMAP3_CONTROL_IDCODE 0x4830A204 +#define OMAP34xx_ProdID_SKUID 0x4830A20C +#define OMAP3_SYSCON_BASE (0x48000000 + 0x2000 + 0x270) + +#define VERSION_COUNT 2 + +struct ti_cpufreq_data; + +struct ti_cpufreq_soc_data { + const char * const *reg_names; + unsigned long (*efuse_xlate)(struct ti_cpufreq_data *opp_data, + unsigned long efuse); + unsigned long efuse_fallback; + unsigned long efuse_offset; + unsigned long efuse_mask; + unsigned long efuse_shift; + unsigned long rev_offset; + bool multi_regulator; +}; + +struct ti_cpufreq_data { + struct device *cpu_dev; + struct device_node *opp_node; + struct regmap *syscon; + const struct ti_cpufreq_soc_data *soc_data; +}; + +static unsigned long amx3_efuse_xlate(struct ti_cpufreq_data *opp_data, + unsigned long efuse) +{ + if (!efuse) + efuse = opp_data->soc_data->efuse_fallback; + /* AM335x and AM437x use "OPP disable" bits, so invert */ + return ~efuse; +} + +static unsigned long dra7_efuse_xlate(struct ti_cpufreq_data *opp_data, + unsigned long efuse) +{ + unsigned long calculated_efuse = DRA7_EFUSE_NOM_MPU_OPP; + + /* + * The efuse on dra7 and am57 parts contains a specific + * value indicating the highest available OPP. + */ + + switch (efuse) { + case DRA76_EFUSE_HAS_PLUS_MPU_OPP: + case DRA76_EFUSE_HAS_ALL_MPU_OPP: + calculated_efuse |= DRA76_EFUSE_PLUS_MPU_OPP; + fallthrough; + case DRA7_EFUSE_HAS_ALL_MPU_OPP: + case DRA7_EFUSE_HAS_HIGH_MPU_OPP: + calculated_efuse |= DRA7_EFUSE_HIGH_MPU_OPP; + fallthrough; + case DRA7_EFUSE_HAS_OD_MPU_OPP: + calculated_efuse |= DRA7_EFUSE_OD_MPU_OPP; + } + + return calculated_efuse; +} + +static unsigned long omap3_efuse_xlate(struct ti_cpufreq_data *opp_data, + unsigned long efuse) +{ + /* OPP enable bit ("Speed Binned") */ + return BIT(efuse); +} + +static struct ti_cpufreq_soc_data am3x_soc_data = { + .efuse_xlate = amx3_efuse_xlate, + .efuse_fallback = AM33XX_800M_ARM_MPU_MAX_FREQ, + .efuse_offset = 0x07fc, + .efuse_mask = 0x1fff, + .rev_offset = 0x600, + .multi_regulator = false, +}; + +static struct ti_cpufreq_soc_data am4x_soc_data = { + .efuse_xlate = amx3_efuse_xlate, + .efuse_fallback = AM43XX_600M_ARM_MPU_MAX_FREQ, + .efuse_offset = 0x0610, + .efuse_mask = 0x3f, + .rev_offset = 0x600, + .multi_regulator = false, +}; + +static struct ti_cpufreq_soc_data dra7_soc_data = { + .efuse_xlate = dra7_efuse_xlate, + .efuse_offset = 0x020c, + .efuse_mask = 0xf80000, + .efuse_shift = 19, + .rev_offset = 0x204, + .multi_regulator = true, +}; + +/* + * OMAP35x TRM (SPRUF98K): + * CONTROL_IDCODE (0x4830 A204) describes Silicon revisions. + * Control OMAP Status Register 15:0 (Address 0x4800 244C) + * to separate between omap3503, omap3515, omap3525, omap3530 + * and feature presence. + * There are encodings for versions limited to 400/266MHz + * but we ignore. + * Not clear if this also holds for omap34xx. + * some eFuse values e.g. CONTROL_FUSE_OPP1_VDD1 + * are stored in the SYSCON register range + * Register 0x4830A20C [ProdID.SKUID] [0:3] + * 0x0 for normal 600/430MHz device. + * 0x8 for 720/520MHz device. + * Not clear what omap34xx value is. + */ + +static struct ti_cpufreq_soc_data omap34xx_soc_data = { + .efuse_xlate = omap3_efuse_xlate, + .efuse_offset = OMAP34xx_ProdID_SKUID - OMAP3_SYSCON_BASE, + .efuse_shift = 3, + .efuse_mask = BIT(3), + .rev_offset = OMAP3_CONTROL_IDCODE - OMAP3_SYSCON_BASE, + .multi_regulator = false, +}; + +/* + * AM/DM37x TRM (SPRUGN4M) + * CONTROL_IDCODE (0x4830 A204) describes Silicon revisions. + * Control Device Status Register 15:0 (Address 0x4800 244C) + * to separate between am3703, am3715, dm3725, dm3730 + * and feature presence. + * Speed Binned = Bit 9 + * 0 800/600 MHz + * 1 1000/800 MHz + * some eFuse values e.g. CONTROL_FUSE_OPP 1G_VDD1 + * are stored in the SYSCON register range. + * There is no 0x4830A20C [ProdID.SKUID] register (exists but + * seems to always read as 0). + */ + +static const char * const omap3_reg_names[] = {"cpu0", "vbb", NULL}; + +static struct ti_cpufreq_soc_data omap36xx_soc_data = { + .reg_names = omap3_reg_names, + .efuse_xlate = omap3_efuse_xlate, + .efuse_offset = OMAP3_CONTROL_DEVICE_STATUS - OMAP3_SYSCON_BASE, + .efuse_shift = 9, + .efuse_mask = BIT(9), + .rev_offset = OMAP3_CONTROL_IDCODE - OMAP3_SYSCON_BASE, + .multi_regulator = true, +}; + +/* + * AM3517 is quite similar to AM/DM37x except that it has no + * high speed grade eFuse and no abb ldo + */ + +static struct ti_cpufreq_soc_data am3517_soc_data = { + .efuse_xlate = omap3_efuse_xlate, + .efuse_offset = OMAP3_CONTROL_DEVICE_STATUS - OMAP3_SYSCON_BASE, + .efuse_shift = 0, + .efuse_mask = 0, + .rev_offset = OMAP3_CONTROL_IDCODE - OMAP3_SYSCON_BASE, + .multi_regulator = false, +}; + + +/** + * ti_cpufreq_get_efuse() - Parse and return efuse value present on SoC + * @opp_data: pointer to ti_cpufreq_data context + * @efuse_value: Set to the value parsed from efuse + * + * Returns error code if efuse not read properly. + */ +static int ti_cpufreq_get_efuse(struct ti_cpufreq_data *opp_data, + u32 *efuse_value) +{ + struct device *dev = opp_data->cpu_dev; + u32 efuse; + int ret; + + ret = regmap_read(opp_data->syscon, opp_data->soc_data->efuse_offset, + &efuse); + if (ret == -EIO) { + /* not a syscon register! */ + void __iomem *regs = ioremap(OMAP3_SYSCON_BASE + + opp_data->soc_data->efuse_offset, 4); + + if (!regs) + return -ENOMEM; + efuse = readl(regs); + iounmap(regs); + } + else if (ret) { + dev_err(dev, + "Failed to read the efuse value from syscon: %d\n", + ret); + return ret; + } + + efuse = (efuse & opp_data->soc_data->efuse_mask); + efuse >>= opp_data->soc_data->efuse_shift; + + *efuse_value = opp_data->soc_data->efuse_xlate(opp_data, efuse); + + return 0; +} + +/** + * ti_cpufreq_get_rev() - Parse and return rev value present on SoC + * @opp_data: pointer to ti_cpufreq_data context + * @revision_value: Set to the value parsed from revision register + * + * Returns error code if revision not read properly. + */ +static int ti_cpufreq_get_rev(struct ti_cpufreq_data *opp_data, + u32 *revision_value) +{ + struct device *dev = opp_data->cpu_dev; + u32 revision; + int ret; + + ret = regmap_read(opp_data->syscon, opp_data->soc_data->rev_offset, + &revision); + if (ret == -EIO) { + /* not a syscon register! */ + void __iomem *regs = ioremap(OMAP3_SYSCON_BASE + + opp_data->soc_data->rev_offset, 4); + + if (!regs) + return -ENOMEM; + revision = readl(regs); + iounmap(regs); + } + else if (ret) { + dev_err(dev, + "Failed to read the revision number from syscon: %d\n", + ret); + return ret; + } + + *revision_value = BIT((revision >> REVISION_SHIFT) & REVISION_MASK); + + return 0; +} + +static int ti_cpufreq_setup_syscon_register(struct ti_cpufreq_data *opp_data) +{ + struct device *dev = opp_data->cpu_dev; + struct device_node *np = opp_data->opp_node; + + opp_data->syscon = syscon_regmap_lookup_by_phandle(np, + "syscon"); + if (IS_ERR(opp_data->syscon)) { + dev_err(dev, + "\"syscon\" is missing, cannot use OPPv2 table.\n"); + return PTR_ERR(opp_data->syscon); + } + + return 0; +} + +static const struct of_device_id ti_cpufreq_of_match[] = { + { .compatible = "ti,am33xx", .data = &am3x_soc_data, }, + { .compatible = "ti,am3517", .data = &am3517_soc_data, }, + { .compatible = "ti,am43", .data = &am4x_soc_data, }, + { .compatible = "ti,dra7", .data = &dra7_soc_data }, + { .compatible = "ti,omap34xx", .data = &omap34xx_soc_data, }, + { .compatible = "ti,omap36xx", .data = &omap36xx_soc_data, }, + /* legacy */ + { .compatible = "ti,omap3430", .data = &omap34xx_soc_data, }, + { .compatible = "ti,omap3630", .data = &omap36xx_soc_data, }, + {}, +}; + +static const struct of_device_id *ti_cpufreq_match_node(void) +{ + struct device_node *np; + const struct of_device_id *match; + + np = of_find_node_by_path("/"); + match = of_match_node(ti_cpufreq_of_match, np); + of_node_put(np); + + return match; +} + +static int ti_cpufreq_probe(struct platform_device *pdev) +{ + u32 version[VERSION_COUNT]; + const struct of_device_id *match; + struct ti_cpufreq_data *opp_data; + const char * const default_reg_names[] = {"vdd", "vbb", NULL}; + int ret; + struct dev_pm_opp_config config = { + .supported_hw = version, + .supported_hw_count = ARRAY_SIZE(version), + }; + + match = dev_get_platdata(&pdev->dev); + if (!match) + return -ENODEV; + + opp_data = devm_kzalloc(&pdev->dev, sizeof(*opp_data), GFP_KERNEL); + if (!opp_data) + return -ENOMEM; + + opp_data->soc_data = match->data; + + opp_data->cpu_dev = get_cpu_device(0); + if (!opp_data->cpu_dev) { + pr_err("%s: Failed to get device for CPU0\n", __func__); + return -ENODEV; + } + + opp_data->opp_node = dev_pm_opp_of_get_opp_desc_node(opp_data->cpu_dev); + if (!opp_data->opp_node) { + dev_info(opp_data->cpu_dev, + "OPP-v2 not supported, cpufreq-dt will attempt to use legacy tables.\n"); + goto register_cpufreq_dt; + } + + ret = ti_cpufreq_setup_syscon_register(opp_data); + if (ret) + goto fail_put_node; + + /* + * OPPs determine whether or not they are supported based on + * two metrics: + * 0 - SoC Revision + * 1 - eFuse value + */ + ret = ti_cpufreq_get_rev(opp_data, &version[0]); + if (ret) + goto fail_put_node; + + ret = ti_cpufreq_get_efuse(opp_data, &version[1]); + if (ret) + goto fail_put_node; + + if (opp_data->soc_data->multi_regulator) { + if (opp_data->soc_data->reg_names) + config.regulator_names = opp_data->soc_data->reg_names; + else + config.regulator_names = default_reg_names; + } + + ret = dev_pm_opp_set_config(opp_data->cpu_dev, &config); + if (ret < 0) { + dev_err(opp_data->cpu_dev, "Failed to set OPP config\n"); + goto fail_put_node; + } + + of_node_put(opp_data->opp_node); + +register_cpufreq_dt: + platform_device_register_simple("cpufreq-dt", -1, NULL, 0); + + return 0; + +fail_put_node: + of_node_put(opp_data->opp_node); + + return ret; +} + +static int __init ti_cpufreq_init(void) +{ + const struct of_device_id *match; + + /* Check to ensure we are on a compatible platform */ + match = ti_cpufreq_match_node(); + if (match) + platform_device_register_data(NULL, "ti-cpufreq", -1, match, + sizeof(*match)); + + return 0; +} +module_init(ti_cpufreq_init); + +static struct platform_driver ti_cpufreq_driver = { + .probe = ti_cpufreq_probe, + .driver = { + .name = "ti-cpufreq", + }, +}; +builtin_platform_driver(ti_cpufreq_driver); + +MODULE_DESCRIPTION("TI CPUFreq/OPP hw-supported driver"); +MODULE_AUTHOR("Dave Gerlach <d-gerlach@ti.com>"); +MODULE_LICENSE("GPL v2"); |