Commit 763dc90e authored by Quan Nguyen's avatar Quan Nguyen Committed by Greg Kroah-Hartman
Browse files

misc: smpro-misc: Add Ampere's Altra SMpro misc driver 



Add driver support for accessing various information reported by
Ampere's SMpro co-processor such as Boot Progress and other
miscellaneous data.

Signed-off-by: default avatarQuan Nguyen <quan@os.amperecomputing.com>
Link: https://lore.kernel.org/r/20221031024442.2490881-4-quan@os.amperecomputing.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4a4a4e9e

Documentation/ABI/testing/sysfs-bus-platform-devices-ampere-smpro

+48 −0
Original line number Diff line number Diff line
@@ -262,3 +262,51 @@ Description: 
		For more details, see section `5.7 GPI Status Registers,

		Altra Family Soc BMC Interface Specification`.



What:		/sys/bus/platform/devices/smpro-misc.*/boot_progress

KernelVersion:	6.1

Contact:	Quan Nguyen <quan@os.amperecomputing.com>

Description:

		(RO) Contains the boot stages information in hex as format below::



		    AABBCCCCCCCC



		where:



		  - ``AA``      : The boot stages



		    - 00: SMpro firmware booting

		    - 01: PMpro firmware booting

		    - 02: ATF BL1 firmware booting

		    - 03: DDR initialization

		    - 04: DDR training report status

		    - 05: ATF BL2 firmware booting

		    - 06: ATF BL31 firmware booting

		    - 07: ATF BL32 firmware booting

		    - 08: UEFI firmware booting

		    - 09: OS booting



		  - ``BB``      : Boot status



		    - 00: Not started

		    - 01: Started

		    - 02: Completed without error

		    - 03: Failed.



		  - ``CCCCCCCC``: Boot status information defined for each boot stages



		For details, see section `5.11 Boot Stage Register Definitions`

		and section `6. Processor Boot Progress Codes, Altra Family Soc BMC

		Interface Specification`.





What:		/sys/bus/platform/devices/smpro-misc*/soc_power_limit

KernelVersion:	6.1

Contact:	Quan Nguyen <quan@os.amperecomputing.com>

Description:

		(RW) Contains the desired SoC power limit in Watt.

		Writes to this sysfs set the desired SoC power limit (W).

		Reads from this register return the current SoC power limit (W).

		The value ranges:



		  - Minimum: 120 W

		  - Maximum: Socket TDP power

drivers/misc/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -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

drivers/misc/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -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

drivers/misc/smpro-misc.c

0 → 100644
+145 −0
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// 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, &reg);

	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, &reg_lo);

	if (!ret)

		ret = regmap_read(misc->regmap, BOOTSTAGE_HI, &reg);

	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@os.amperecomputing.com>");

MODULE_AUTHOR("Quan Nguyen <quan@os.amperecomputing.com>");

MODULE_DESCRIPTION("Ampere Altra SMpro Misc driver");

MODULE_LICENSE("GPL");