This commit adds driver support for accessing various information reported by Ampere's SMpro co-processor such as Boot Progress and other miscellaneous data. Signed-off-by: Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx> --- Changes in v9: + Update SPDX licence [Greg] + Use ATTRIBUTE_GROUPS() [Greg] + Use dev_groups instead of sysfs_create_group() to avoid racing issue with user space [Greg] + Refactor code to avoid clever encoding issue [Quan] Changes in v8: + Update wording for SMPRO_MISC in Kconfig file [Quan] + Switch to use sysfs_emit() [Quan] Changes in v7: + Fix wrong return type of *_show/store() functions [kernel robot test] + Adjust patch order to remove dependence with smpro-mfd [Lee Jones] Changes in v6: + First introduced in v6 [Quan] drivers/misc/Kconfig | 10 +++ drivers/misc/Makefile | 1 + drivers/misc/smpro-misc.c | 145 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 156 insertions(+) create mode 100644 drivers/misc/smpro-misc.c diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index b9ceee949dab..9947b7892bd5 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -188,6 +188,16 @@ config SMPRO_ERRMON To compile this driver as a module, say M here. The driver will be called smpro-errmon. +config SMPRO_MISC + tristate "Ampere Computing SMPro miscellaneous driver" + depends on MFD_SMPRO || COMPILE_TEST + help + Say Y here to get support for the SMpro error miscellalenous function + provided by Ampere Computing's Altra and Altra Max SoCs. + + To compile this driver as a module, say M here. The driver will be + called smpro-misc. + config CS5535_MFGPT tristate "CS5535/CS5536 Geode Multi-Function General Purpose Timer (MFGPT) support" depends on MFD_CS5535 diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index bbe24d4511a3..87b54a4a4422 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -24,6 +24,7 @@ obj-$(CONFIG_KGDB_TESTS) += kgdbts.o obj-$(CONFIG_SGI_XP) += sgi-xp/ obj-$(CONFIG_SGI_GRU) += sgi-gru/ obj-$(CONFIG_SMPRO_ERRMON) += smpro-errmon.o +obj-$(CONFIG_SMPRO_MISC) += smpro-misc.o obj-$(CONFIG_CS5535_MFGPT) += cs5535-mfgpt.o obj-$(CONFIG_GEHC_ACHC) += gehc-achc.o obj-$(CONFIG_HP_ILO) += hpilo.o diff --git a/drivers/misc/smpro-misc.c b/drivers/misc/smpro-misc.c new file mode 100644 index 000000000000..6c427141e51b --- /dev/null +++ b/drivers/misc/smpro-misc.c @@ -0,0 +1,145 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Ampere Computing SoC's SMpro Misc Driver + * + * Copyright (c) 2022, Ampere Computing LLC + */ +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +/* Boot Stage/Progress Registers */ +#define BOOTSTAGE 0xB0 +#define BOOTSTAGE_LO 0xB1 +#define CUR_BOOTSTAGE 0xB2 +#define BOOTSTAGE_HI 0xB3 + +/* SOC State Registers */ +#define SOC_POWER_LIMIT 0xE5 + +struct smpro_misc { + struct regmap *regmap; +}; + +static ssize_t boot_progress_show(struct device *dev, struct device_attribute *da, char *buf) +{ + struct smpro_misc *misc = dev_get_drvdata(dev); + u16 boot_progress[3] = { 0 }; + u32 bootstage; + u8 boot_stage; + u8 cur_stage; + u32 reg_lo; + u32 reg; + int ret; + + /* Read current boot stage */ + ret = regmap_read(misc->regmap, CUR_BOOTSTAGE, ®); + if (ret) + return ret; + + cur_stage = reg & 0xff; + + ret = regmap_read(misc->regmap, BOOTSTAGE, &bootstage); + if (ret) + return ret; + + boot_stage = (bootstage >> 8) & 0xff; + + if (boot_stage > cur_stage) + return -EINVAL; + + ret = regmap_read(misc->regmap, BOOTSTAGE_LO, ®_lo); + if (!ret) + ret = regmap_read(misc->regmap, BOOTSTAGE_HI, ®); + if (ret) + return ret; + + /* Firmware to report new boot stage next time */ + if (boot_stage < cur_stage) { + ret = regmap_write(misc->regmap, BOOTSTAGE, ((bootstage & 0xff00) | 0x1)); + if (ret) + return ret; + } + + boot_progress[0] = bootstage; + boot_progress[1] = swab16(reg); + boot_progress[2] = swab16(reg_lo); + + return sysfs_emit(buf, "%*phN\n", (int)sizeof(boot_progress), boot_progress); +} + +static DEVICE_ATTR_RO(boot_progress); + +static ssize_t soc_power_limit_show(struct device *dev, struct device_attribute *da, char *buf) +{ + struct smpro_misc *misc = dev_get_drvdata(dev); + unsigned int value; + int ret; + + ret = regmap_read(misc->regmap, SOC_POWER_LIMIT, &value); + if (ret) + return ret; + + return sysfs_emit(buf, "%d\n", value); +} + +static ssize_t soc_power_limit_store(struct device *dev, struct device_attribute *da, + const char *buf, size_t count) +{ + struct smpro_misc *misc = dev_get_drvdata(dev); + unsigned long val; + s32 ret; + + ret = kstrtoul(buf, 0, &val); + if (ret) + return ret; + + ret = regmap_write(misc->regmap, SOC_POWER_LIMIT, (unsigned int)val); + if (ret) + return -EPROTO; + + return count; +} + +static DEVICE_ATTR_RW(soc_power_limit); + +static struct attribute *smpro_misc_attrs[] = { + &dev_attr_boot_progress.attr, + &dev_attr_soc_power_limit.attr, + NULL +}; + +ATTRIBUTE_GROUPS(smpro_misc); + +static int smpro_misc_probe(struct platform_device *pdev) +{ + struct smpro_misc *misc; + + misc = devm_kzalloc(&pdev->dev, sizeof(struct smpro_misc), GFP_KERNEL); + if (!misc) + return -ENOMEM; + + platform_set_drvdata(pdev, misc); + + misc->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!misc->regmap) + return -ENODEV; + + return 0; +} + +static struct platform_driver smpro_misc_driver = { + .probe = smpro_misc_probe, + .driver = { + .name = "smpro-misc", + .dev_groups = smpro_misc_groups, + }, +}; + +module_platform_driver(smpro_misc_driver); + +MODULE_AUTHOR("Tung Nguyen <tungnguyen@xxxxxxxxxxxxxxxxxxxxxx>"); +MODULE_AUTHOR("Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Ampere Altra SMpro Misc driver"); +MODULE_LICENSE("GPL"); -- 2.35.1