linux/drivers/soc/tegra/pmc-tegra186.c

170 lines
4.5 KiB
C

/*
* 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);