diff options
Diffstat (limited to 'drivers/soc/tegra/pmc-tegra186.c')
| -rw-r--r-- | drivers/soc/tegra/pmc-tegra186.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/drivers/soc/tegra/pmc-tegra186.c b/drivers/soc/tegra/pmc-tegra186.c new file mode 100644 index 000000000000..6f5c6f98ba92 --- /dev/null +++ b/drivers/soc/tegra/pmc-tegra186.c @@ -0,0 +1,169 @@ +/* + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#define pr_fmt(fmt) "tegra-pmc: " fmt + +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reboot.h> + +#include <asm/system_misc.h> + +#define PMC_CNTRL 0x000 +#define PMC_CNTRL_MAIN_RST BIT(4) + +#define PMC_RST_STATUS 0x070 + +#define WAKE_AOWAKE_CTRL 0x4f4 +#define WAKE_AOWAKE_CTRL_INTR_POLARITY BIT(0) + +#define SCRATCH_SCRATCH0 0x2000 +#define SCRATCH_SCRATCH0_MODE_RECOVERY BIT(31) +#define SCRATCH_SCRATCH0_MODE_BOOTLOADER BIT(30) +#define SCRATCH_SCRATCH0_MODE_RCM BIT(1) +#define SCRATCH_SCRATCH0_MODE_MASK (SCRATCH_SCRATCH0_MODE_RECOVERY | \ + SCRATCH_SCRATCH0_MODE_BOOTLOADER | \ + SCRATCH_SCRATCH0_MODE_RCM) + +struct tegra_pmc { + struct device *dev; + void __iomem *regs; + void __iomem *wake; + void __iomem *aotag; + void __iomem *scratch; + + void (*system_restart)(enum reboot_mode mode, const char *cmd); + struct notifier_block restart; +}; + +static int tegra186_pmc_restart_notify(struct notifier_block *nb, + unsigned long action, + void *data) +{ + struct tegra_pmc *pmc = container_of(nb, struct tegra_pmc, restart); + const char *cmd = data; + u32 value; + + value = readl(pmc->scratch + SCRATCH_SCRATCH0); + value &= ~SCRATCH_SCRATCH0_MODE_MASK; + + if (cmd) { + if (strcmp(cmd, "recovery") == 0) + value |= SCRATCH_SCRATCH0_MODE_RECOVERY; + + if (strcmp(cmd, "bootloader") == 0) + value |= SCRATCH_SCRATCH0_MODE_BOOTLOADER; + + if (strcmp(cmd, "forced-recovery") == 0) + value |= SCRATCH_SCRATCH0_MODE_RCM; + } + + writel(value, pmc->scratch + SCRATCH_SCRATCH0); + + /* + * If available, call the system restart implementation that was + * registered earlier (typically PSCI). + */ + if (pmc->system_restart) { + pmc->system_restart(reboot_mode, cmd); + return NOTIFY_DONE; + } + + /* reset everything but SCRATCH0_SCRATCH0 and PMC_RST_STATUS */ + value = readl(pmc->regs + PMC_CNTRL); + value |= PMC_CNTRL_MAIN_RST; + writel(value, pmc->regs + PMC_CNTRL); + + return NOTIFY_DONE; +} + +static int tegra186_pmc_setup(struct tegra_pmc *pmc) +{ + struct device_node *np = pmc->dev->of_node; + bool invert; + u32 value; + + invert = of_property_read_bool(np, "nvidia,invert-interrupt"); + + value = readl(pmc->wake + WAKE_AOWAKE_CTRL); + + if (invert) + value |= WAKE_AOWAKE_CTRL_INTR_POLARITY; + else + value &= ~WAKE_AOWAKE_CTRL_INTR_POLARITY; + + writel(value, pmc->wake + WAKE_AOWAKE_CTRL); + + /* + * We need to hook any system restart implementation registered + * previously so we can write SCRATCH_SCRATCH0 before reset. + */ + pmc->system_restart = arm_pm_restart; + arm_pm_restart = NULL; + + pmc->restart.notifier_call = tegra186_pmc_restart_notify; + pmc->restart.priority = 128; + + return register_restart_handler(&pmc->restart); +} + +static int tegra186_pmc_probe(struct platform_device *pdev) +{ + struct tegra_pmc *pmc; + struct resource *res; + + pmc = devm_kzalloc(&pdev->dev, sizeof(*pmc), GFP_KERNEL); + if (!pmc) + return -ENOMEM; + + pmc->dev = &pdev->dev; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pmc"); + pmc->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pmc->regs)) + return PTR_ERR(pmc->regs); + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "wake"); + pmc->wake = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pmc->wake)) + return PTR_ERR(pmc->wake); + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "aotag"); + pmc->aotag = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pmc->aotag)) + return PTR_ERR(pmc->aotag); + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "scratch"); + pmc->scratch = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pmc->scratch)) + return PTR_ERR(pmc->scratch); + + return tegra186_pmc_setup(pmc); +} + +static const struct of_device_id tegra186_pmc_of_match[] = { + { .compatible = "nvidia,tegra186-pmc" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, tegra186_pmc_of_match); + +static struct platform_driver tegra186_pmc_driver = { + .driver = { + .name = "tegra186-pmc", + .of_match_table = tegra186_pmc_of_match, + }, + .probe = tegra186_pmc_probe, +}; +builtin_platform_driver(tegra186_pmc_driver); |