cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

qcom-pon.c (2515B)

      1// SPDX-License-Identifier: GPL-2.0
      2// Copyright (c) 2017-18 Linaro Limited
      3
      4#include <linux/delay.h>
      5#include <linux/errno.h>
      6#include <linux/kernel.h>
      7#include <linux/module.h>
      8#include <linux/of.h>
      9#include <linux/of_platform.h>
     10#include <linux/platform_device.h>
     11#include <linux/reboot.h>
     12#include <linux/reboot-mode.h>
     13#include <linux/regmap.h>
     14
     15#define PON_SOFT_RB_SPARE		0x8f
     16
     17#define GEN1_REASON_SHIFT		2
     18#define GEN2_REASON_SHIFT		1
     19
     20struct pm8916_pon {
     21	struct device *dev;
     22	struct regmap *regmap;
     23	u32 baseaddr;
     24	struct reboot_mode_driver reboot_mode;
     25	long reason_shift;
     26};
     27
     28static int pm8916_reboot_mode_write(struct reboot_mode_driver *reboot,
     29				    unsigned int magic)
     30{
     31	struct pm8916_pon *pon = container_of
     32			(reboot, struct pm8916_pon, reboot_mode);
     33	int ret;
     34
     35	ret = regmap_update_bits(pon->regmap,
     36				 pon->baseaddr + PON_SOFT_RB_SPARE,
     37				 GENMASK(7, pon->reason_shift),
     38				 magic << pon->reason_shift);
     39	if (ret < 0)
     40		dev_err(pon->dev, "update reboot mode bits failed\n");
     41
     42	return ret;
     43}
     44
     45static int pm8916_pon_probe(struct platform_device *pdev)
     46{
     47	struct pm8916_pon *pon;
     48	int error;
     49
     50	pon = devm_kzalloc(&pdev->dev, sizeof(*pon), GFP_KERNEL);
     51	if (!pon)
     52		return -ENOMEM;
     53
     54	pon->dev = &pdev->dev;
     55
     56	pon->regmap = dev_get_regmap(pdev->dev.parent, NULL);
     57	if (!pon->regmap) {
     58		dev_err(&pdev->dev, "failed to locate regmap\n");
     59		return -ENODEV;
     60	}
     61
     62	error = of_property_read_u32(pdev->dev.of_node, "reg",
     63				     &pon->baseaddr);
     64	if (error)
     65		return error;
     66
     67	pon->reboot_mode.dev = &pdev->dev;
     68	pon->reason_shift = (long)of_device_get_match_data(&pdev->dev);
     69	pon->reboot_mode.write = pm8916_reboot_mode_write;
     70	error = devm_reboot_mode_register(&pdev->dev, &pon->reboot_mode);
     71	if (error) {
     72		dev_err(&pdev->dev, "can't register reboot mode\n");
     73		return error;
     74	}
     75
     76	platform_set_drvdata(pdev, pon);
     77
     78	return devm_of_platform_populate(&pdev->dev);
     79}
     80
     81static const struct of_device_id pm8916_pon_id_table[] = {
     82	{ .compatible = "qcom,pm8916-pon", .data = (void *)GEN1_REASON_SHIFT },
     83	{ .compatible = "qcom,pms405-pon", .data = (void *)GEN1_REASON_SHIFT },
     84	{ .compatible = "qcom,pm8998-pon", .data = (void *)GEN2_REASON_SHIFT },
     85	{ }
     86};
     87MODULE_DEVICE_TABLE(of, pm8916_pon_id_table);
     88
     89static struct platform_driver pm8916_pon_driver = {
     90	.probe = pm8916_pon_probe,
     91	.driver = {
     92		.name = "pm8916-pon",
     93		.of_match_table = of_match_ptr(pm8916_pon_id_table),
     94	},
     95};
     96module_platform_driver(pm8916_pon_driver);
     97
     98MODULE_DESCRIPTION("pm8916 Power On driver");
     99MODULE_LICENSE("GPL v2");