// SPDX-License-Identifier: GPL-2.0-only
/*
 * AMD Secure Processor device driver
 *
 * Copyright (C) 2014,2018 Advanced Micro Devices, Inc.
 *
 * Author: Tom Lendacky <thomas.lendacky@amd.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/ioport.h>
#include <linux/dma-mapping.h>
#include <linux/kthread.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/delay.h>
#include <linux/ccp.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/acpi.h>

#include "ccp-dev.h"

struct sp_platform {
        int coherent;
        unsigned int irq_count;
};

static const struct sp_dev_vdata dev_vdata[] = {
        {
                .bar = 0,
#ifdef CONFIG_CRYPTO_DEV_SP_CCP
                .ccp_vdata = &ccpv3_platform,
#endif
        },
};

static const struct acpi_device_id sp_acpi_match[] = {
        { "AMDI0C00", (kernel_ulong_t)&dev_vdata[0] },
        { },
};
MODULE_DEVICE_TABLE(acpi, sp_acpi_match);

static const struct of_device_id sp_of_match[] = {
        { .compatible = "amd,ccp-seattle-v1a",
          .data = (const void *)&dev_vdata[0] },
        { },
};
MODULE_DEVICE_TABLE(of, sp_of_match);

static const struct sp_dev_vdata *sp_get_acpi_version(struct platform_device *pdev)
{
        const struct acpi_device_id *match;

        match = acpi_match_device(sp_acpi_match, &pdev->dev);
        if (match && match->driver_data)
                return (const struct sp_dev_vdata *)match->driver_data;

        return NULL;
}

static int sp_get_irqs(struct sp_device *sp)
{
        struct sp_platform *sp_platform = sp->dev_specific;
        struct device *dev = sp->dev;
        struct platform_device *pdev = to_platform_device(dev);
        int ret;

        sp_platform->irq_count = platform_irq_count(pdev);

        ret = platform_get_irq(pdev, 0);
        if (ret < 0) {
                dev_notice(dev, "unable to get IRQ (%d)\n", ret);
                return ret;
        }

        sp->psp_irq = ret;
        if (sp_platform->irq_count == 1) {
                sp->ccp_irq = ret;
        } else {
                ret = platform_get_irq(pdev, 1);
                if (ret < 0) {
                        dev_notice(dev, "unable to get IRQ (%d)\n", ret);
                        return ret;
                }

                sp->ccp_irq = ret;
        }

        return 0;
}

static int sp_platform_probe(struct platform_device *pdev)
{
        struct sp_device *sp;
        struct sp_platform *sp_platform;
        struct device *dev = &pdev->dev;
        enum dev_dma_attr attr;
        int ret;

        ret = -ENOMEM;
        sp = sp_alloc_struct(dev);
        if (!sp)
                goto e_err;

        sp_platform = devm_kzalloc(dev, sizeof(*sp_platform), GFP_KERNEL);
        if (!sp_platform)
                goto e_err;

        sp->dev_specific = sp_platform;
        sp->dev_vdata = pdev->dev.of_node ? of_device_get_match_data(&pdev->dev)
                                         : sp_get_acpi_version(pdev);
        if (!sp->dev_vdata) {
                ret = -ENODEV;
                dev_err(dev, "missing driver data\n");
                goto e_err;
        }

        sp->io_map = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(sp->io_map)) {
                ret = PTR_ERR(sp->io_map);
                goto e_err;
        }

        attr = device_get_dma_attr(dev);
        if (attr == DEV_DMA_NOT_SUPPORTED) {
                dev_err(dev, "DMA is not supported");
                goto e_err;
        }

        sp_platform->coherent = (attr == DEV_DMA_COHERENT);
        if (sp_platform->coherent)
                sp->axcache = CACHE_WB_NO_ALLOC;
        else
                sp->axcache = CACHE_NONE;

        ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48));
        if (ret) {
                dev_err(dev, "dma_set_mask_and_coherent failed (%d)\n", ret);
                goto e_err;
        }

        ret = sp_get_irqs(sp);
        if (ret)
                goto e_err;

        dev_set_drvdata(dev, sp);

        ret = sp_init(sp);
        if (ret)
                goto e_err;

        dev_notice(dev, "enabled\n");

        return 0;

e_err:
        dev_notice(dev, "initialization failed\n");
        return ret;
}

static void sp_platform_remove(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct sp_device *sp = dev_get_drvdata(dev);

        sp_destroy(sp);

        dev_notice(dev, "disabled\n");
}

#ifdef CONFIG_PM
static int sp_platform_suspend(struct platform_device *pdev,
                                pm_message_t state)
{
        struct device *dev = &pdev->dev;
        struct sp_device *sp = dev_get_drvdata(dev);

        return sp_suspend(sp);
}

static int sp_platform_resume(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct sp_device *sp = dev_get_drvdata(dev);

        return sp_resume(sp);
}
#endif

static struct platform_driver sp_platform_driver = {
        .driver = {
                .name = "ccp",
                .acpi_match_table = sp_acpi_match,
                .of_match_table = sp_of_match,
        },
        .probe = sp_platform_probe,
        .remove = sp_platform_remove,
#ifdef CONFIG_PM
        .suspend = sp_platform_suspend,
        .resume = sp_platform_resume,
#endif
};

int sp_platform_init(void)
{
        return platform_driver_register(&sp_platform_driver);
}

void sp_platform_exit(void)
{
        platform_driver_unregister(&sp_platform_driver);
}