// SPDX-License-Identifier: GPL-2.0-only
/*
 * Tegra host1x driver
 *
 * Copyright (c) 2010-2013, NVIDIA Corporation.
 */

#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of.h>
#include <linux/slab.h>

#define CREATE_TRACE_POINTS
#include <trace/events/host1x.h>
#undef CREATE_TRACE_POINTS

#include "bus.h"
#include "channel.h"
#include "debug.h"
#include "dev.h"
#include "intr.h"

#include "hw/host1x01.h"
#include "hw/host1x02.h"
#include "hw/host1x04.h"
#include "hw/host1x05.h"
#include "hw/host1x06.h"
#include "hw/host1x07.h"

void host1x_hypervisor_writel(struct host1x *host1x, u32 v, u32 r)
{
        writel(v, host1x->hv_regs + r);
}

u32 host1x_hypervisor_readl(struct host1x *host1x, u32 r)
{
        return readl(host1x->hv_regs + r);
}

void host1x_sync_writel(struct host1x *host1x, u32 v, u32 r)
{
        void __iomem *sync_regs = host1x->regs + host1x->info->sync_offset;

        writel(v, sync_regs + r);
}

u32 host1x_sync_readl(struct host1x *host1x, u32 r)
{
        void __iomem *sync_regs = host1x->regs + host1x->info->sync_offset;

        return readl(sync_regs + r);
}

void host1x_ch_writel(struct host1x_channel *ch, u32 v, u32 r)
{
        writel(v, ch->regs + r);
}

u32 host1x_ch_readl(struct host1x_channel *ch, u32 r)
{
        return readl(ch->regs + r);
}

static const struct host1x_info host1x01_info = {
        .nb_channels = 8,
        .nb_pts = 32,
        .nb_mlocks = 16,
        .nb_bases = 8,
        .init = host1x01_init,
        .sync_offset = 0x3000,
        .dma_mask = DMA_BIT_MASK(32),
        .has_wide_gather = false,
        .has_hypervisor = false,
        .num_sid_entries = 0,
        .sid_table = NULL,
        .reserve_vblank_syncpts = true,
};

static const struct host1x_info host1x02_info = {
        .nb_channels = 9,
        .nb_pts = 32,
        .nb_mlocks = 16,
        .nb_bases = 12,
        .init = host1x02_init,
        .sync_offset = 0x3000,
        .dma_mask = DMA_BIT_MASK(32),
        .has_wide_gather = false,
        .has_hypervisor = false,
        .num_sid_entries = 0,
        .sid_table = NULL,
        .reserve_vblank_syncpts = true,
};

static const struct host1x_info host1x04_info = {
        .nb_channels = 12,
        .nb_pts = 192,
        .nb_mlocks = 16,
        .nb_bases = 64,
        .init = host1x04_init,
        .sync_offset = 0x2100,
        .dma_mask = DMA_BIT_MASK(34),
        .has_wide_gather = false,
        .has_hypervisor = false,
        .num_sid_entries = 0,
        .sid_table = NULL,
        .reserve_vblank_syncpts = false,
};

static const struct host1x_info host1x05_info = {
        .nb_channels = 14,
        .nb_pts = 192,
        .nb_mlocks = 16,
        .nb_bases = 64,
        .init = host1x05_init,
        .sync_offset = 0x2100,
        .dma_mask = DMA_BIT_MASK(34),
        .has_wide_gather = false,
        .has_hypervisor = false,
        .num_sid_entries = 0,
        .sid_table = NULL,
        .reserve_vblank_syncpts = false,
};

static const struct host1x_sid_entry tegra186_sid_table[] = {
        {
                /* VIC */
                .base = 0x1af0,
                .offset = 0x30,
                .limit = 0x34
        },
};

static const struct host1x_info host1x06_info = {
        .nb_channels = 63,
        .nb_pts = 576,
        .nb_mlocks = 24,
        .nb_bases = 16,
        .init = host1x06_init,
        .sync_offset = 0x0,
        .dma_mask = DMA_BIT_MASK(40),
        .has_wide_gather = true,
        .has_hypervisor = true,
        .num_sid_entries = ARRAY_SIZE(tegra186_sid_table),
        .sid_table = tegra186_sid_table,
        .reserve_vblank_syncpts = false,
};

static const struct host1x_sid_entry tegra194_sid_table[] = {
        {
                /* VIC */
                .base = 0x1af0,
                .offset = 0x30,
                .limit = 0x34
        },
};

static const struct host1x_info host1x07_info = {
        .nb_channels = 63,
        .nb_pts = 704,
        .nb_mlocks = 32,
        .nb_bases = 0,
        .init = host1x07_init,
        .sync_offset = 0x0,
        .dma_mask = DMA_BIT_MASK(40),
        .has_wide_gather = true,
        .has_hypervisor = true,
        .num_sid_entries = ARRAY_SIZE(tegra194_sid_table),
        .sid_table = tegra194_sid_table,
        .reserve_vblank_syncpts = false,
};

static const struct of_device_id host1x_of_match[] = {
        { .compatible = "nvidia,tegra194-host1x", .data = &host1x07_info, },
        { .compatible = "nvidia,tegra186-host1x", .data = &host1x06_info, },
        { .compatible = "nvidia,tegra210-host1x", .data = &host1x05_info, },
        { .compatible = "nvidia,tegra124-host1x", .data = &host1x04_info, },
        { .compatible = "nvidia,tegra114-host1x", .data = &host1x02_info, },
        { .compatible = "nvidia,tegra30-host1x", .data = &host1x01_info, },
        { .compatible = "nvidia,tegra20-host1x", .data = &host1x01_info, },
        { },
};
MODULE_DEVICE_TABLE(of, host1x_of_match);

static void host1x_setup_sid_table(struct host1x *host)
{
        const struct host1x_info *info = host->info;
        unsigned int i;

        for (i = 0; i < info->num_sid_entries; i++) {
                const struct host1x_sid_entry *entry = &info->sid_table[i];

                host1x_hypervisor_writel(host, entry->offset, entry->base);
                host1x_hypervisor_writel(host, entry->limit, entry->base + 4);
        }
}

static bool host1x_wants_iommu(struct host1x *host1x)
{
        /*
         * If we support addressing a maximum of 32 bits of physical memory
         * and if the host1x firewall is enabled, there's no need to enable
         * IOMMU support. This can happen for example on Tegra20, Tegra30
         * and Tegra114.
         *
         * Tegra124 and later can address up to 34 bits of physical memory and
         * many platforms come equipped with more than 2 GiB of system memory,
         * which requires crossing the 4 GiB boundary. But there's a catch: on
         * SoCs before Tegra186 (i.e. Tegra124 and Tegra210), the host1x can
         * only address up to 32 bits of memory in GATHER opcodes, which means
         * that command buffers need to either be in the first 2 GiB of system
         * memory (which could quickly lead to memory exhaustion), or command
         * buffers need to be treated differently from other buffers (which is
         * not possible with the current ABI).
         *
         * A third option is to use the IOMMU in these cases to make sure all
         * buffers will be mapped into a 32-bit IOVA space that host1x can
         * address. This allows all of the system memory to be used and works
         * within the limitations of the host1x on these SoCs.
         *
         * In summary, default to enable IOMMU on Tegra124 and later. For any
         * of the earlier SoCs, only use the IOMMU for additional safety when
         * the host1x firewall is disabled.
         */
        if (host1x->info->dma_mask <= DMA_BIT_MASK(32)) {
                if (IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL))
                        return false;
        }

        return true;
}

static struct iommu_domain *host1x_iommu_attach(struct host1x *host)
{
        struct iommu_domain *domain = iommu_get_domain_for_dev(host->dev);
        int err;

        /*
         * We may not always want to enable IOMMU support (for example if the
         * host1x firewall is already enabled and we don't support addressing
         * more than 32 bits of physical memory), so check for that first.
         *
         * Similarly, if host1x is already attached to an IOMMU (via the DMA
         * API), don't try to attach again.
         */
        if (!host1x_wants_iommu(host) || domain)
                return domain;

        host->group = iommu_group_get(host->dev);
        if (host->group) {
                struct iommu_domain_geometry *geometry;
                dma_addr_t start, end;
                unsigned long order;

                err = iova_cache_get();
                if (err < 0)
                        goto put_group;

                host->domain = iommu_domain_alloc(&platform_bus_type);
                if (!host->domain) {
                        err = -ENOMEM;
                        goto put_cache;
                }

                err = iommu_attach_group(host->domain, host->group);
                if (err) {
                        if (err == -ENODEV)
                                err = 0;

                        goto free_domain;
                }

                geometry = &host->domain->geometry;
                start = geometry->aperture_start & host->info->dma_mask;
                end = geometry->aperture_end & host->info->dma_mask;

                order = __ffs(host->domain->pgsize_bitmap);
                init_iova_domain(&host->iova, 1UL << order, start >> order);
                host->iova_end = end;

                domain = host->domain;
        }

        return domain;

free_domain:
        iommu_domain_free(host->domain);
        host->domain = NULL;
put_cache:
        iova_cache_put();
put_group:
        iommu_group_put(host->group);
        host->group = NULL;

        return ERR_PTR(err);
}

static int host1x_iommu_init(struct host1x *host)
{
        u64 mask = host->info->dma_mask;
        struct iommu_domain *domain;
        int err;

        domain = host1x_iommu_attach(host);
        if (IS_ERR(domain)) {
                err = PTR_ERR(domain);
                dev_err(host->dev, "failed to attach to IOMMU: %d\n", err);
                return err;
        }

        /*
         * If we're not behind an IOMMU make sure we don't get push buffers
         * that are allocated outside of the range addressable by the GATHER
         * opcode.
         *
         * Newer generations of Tegra (Tegra186 and later) support a wide
         * variant of the GATHER opcode that allows addressing more bits.
         */
        if (!domain && !host->info->has_wide_gather)
                mask = DMA_BIT_MASK(32);

        err = dma_coerce_mask_and_coherent(host->dev, mask);
        if (err < 0) {
                dev_err(host->dev, "failed to set DMA mask: %d\n", err);
                return err;
        }

        return 0;
}

static void host1x_iommu_exit(struct host1x *host)
{
        if (host->domain) {
                put_iova_domain(&host->iova);
                iommu_detach_group(host->domain, host->group);

                iommu_domain_free(host->domain);
                host->domain = NULL;

                iova_cache_put();

                iommu_group_put(host->group);
                host->group = NULL;
        }
}

static int host1x_probe(struct platform_device *pdev)
{
        struct host1x *host;
        struct resource *regs, *hv_regs = NULL;
        int syncpt_irq;
        int err;

        host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
        if (!host)
                return -ENOMEM;

        host->info = of_device_get_match_data(&pdev->dev);

        if (host->info->has_hypervisor) {
                regs = platform_get_resource_byname(pdev, IORESOURCE_MEM, "vm");
                if (!regs) {
                        dev_err(&pdev->dev, "failed to get vm registers\n");
                        return -ENXIO;
                }

                hv_regs = platform_get_resource_byname(pdev, IORESOURCE_MEM,
                                                       "hypervisor");
                if (!hv_regs) {
                        dev_err(&pdev->dev,
                                "failed to get hypervisor registers\n");
                        return -ENXIO;
                }
        } else {
                regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
                if (!regs) {
                        dev_err(&pdev->dev, "failed to get registers\n");
                        return -ENXIO;
                }
        }

        syncpt_irq = platform_get_irq(pdev, 0);
        if (syncpt_irq < 0)
                return syncpt_irq;

        mutex_init(&host->devices_lock);
        INIT_LIST_HEAD(&host->devices);
        INIT_LIST_HEAD(&host->list);
        host->dev = &pdev->dev;

        /* set common host1x device data */
        platform_set_drvdata(pdev, host);

        host->regs = devm_ioremap_resource(&pdev->dev, regs);
        if (IS_ERR(host->regs))
                return PTR_ERR(host->regs);

        if (host->info->has_hypervisor) {
                host->hv_regs = devm_ioremap_resource(&pdev->dev, hv_regs);
                if (IS_ERR(host->hv_regs))
                        return PTR_ERR(host->hv_regs);
        }

        host->dev->dma_parms = &host->dma_parms;
        dma_set_max_seg_size(host->dev, UINT_MAX);

        if (host->info->init) {
                err = host->info->init(host);
                if (err)
                        return err;
        }

        host->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(host->clk)) {
                err = PTR_ERR(host->clk);

                if (err != -EPROBE_DEFER)
                        dev_err(&pdev->dev, "failed to get clock: %d\n", err);

                return err;
        }

        host->rst = devm_reset_control_get(&pdev->dev, "host1x");
        if (IS_ERR(host->rst)) {
                err = PTR_ERR(host->rst);
                dev_err(&pdev->dev, "failed to get reset: %d\n", err);
                return err;
        }

        err = host1x_iommu_init(host);
        if (err < 0) {
                dev_err(&pdev->dev, "failed to setup IOMMU: %d\n", err);
                return err;
        }

        err = host1x_channel_list_init(&host->channel_list,
                                       host->info->nb_channels);
        if (err) {
                dev_err(&pdev->dev, "failed to initialize channel list\n");
                goto iommu_exit;
        }

        err = clk_prepare_enable(host->clk);
        if (err < 0) {
                dev_err(&pdev->dev, "failed to enable clock\n");
                goto free_channels;
        }

        err = reset_control_deassert(host->rst);
        if (err < 0) {
                dev_err(&pdev->dev, "failed to deassert reset: %d\n", err);
                goto unprepare_disable;
        }

        err = host1x_syncpt_init(host);
        if (err) {
                dev_err(&pdev->dev, "failed to initialize syncpts\n");
                goto reset_assert;
        }

        err = host1x_intr_init(host, syncpt_irq);
        if (err) {
                dev_err(&pdev->dev, "failed to initialize interrupts\n");
                goto deinit_syncpt;
        }

        host1x_debug_init(host);

        if (host->info->has_hypervisor)
                host1x_setup_sid_table(host);

        err = host1x_register(host);
        if (err < 0)
                goto deinit_debugfs;

        err = devm_of_platform_populate(&pdev->dev);
        if (err < 0)
                goto unregister;

        return 0;

unregister:
        host1x_unregister(host);
deinit_debugfs:
        host1x_debug_deinit(host);
        host1x_intr_deinit(host);
deinit_syncpt:
        host1x_syncpt_deinit(host);
reset_assert:
        reset_control_assert(host->rst);
unprepare_disable:
        clk_disable_unprepare(host->clk);
free_channels:
        host1x_channel_list_free(&host->channel_list);
iommu_exit:
        host1x_iommu_exit(host);

        return err;
}

static int host1x_remove(struct platform_device *pdev)
{
        struct host1x *host = platform_get_drvdata(pdev);

        host1x_unregister(host);
        host1x_debug_deinit(host);
        host1x_intr_deinit(host);
        host1x_syncpt_deinit(host);
        reset_control_assert(host->rst);
        clk_disable_unprepare(host->clk);
        host1x_iommu_exit(host);

        return 0;
}

static struct platform_driver tegra_host1x_driver = {
        .driver = {
                .name = "tegra-host1x",
                .of_match_table = host1x_of_match,
        },
        .probe = host1x_probe,
        .remove = host1x_remove,
};

static struct platform_driver * const drivers[] = {
        &tegra_host1x_driver,
        &tegra_mipi_driver,
};

static int __init tegra_host1x_init(void)
{
        int err;

        err = bus_register(&host1x_bus_type);
        if (err < 0)
                return err;

        err = platform_register_drivers(drivers, ARRAY_SIZE(drivers));
        if (err < 0)
                bus_unregister(&host1x_bus_type);

        return err;
}
module_init(tegra_host1x_init);

static void __exit tegra_host1x_exit(void)
{
        platform_unregister_drivers(drivers, ARRAY_SIZE(drivers));
        bus_unregister(&host1x_bus_type);
}
module_exit(tegra_host1x_exit);

/**
 * host1x_get_dma_mask() - query the supported DMA mask for host1x
 * @host1x: host1x instance
 *
 * Note that this returns the supported DMA mask for host1x, which can be
 * different from the applicable DMA mask under certain circumstances.
 */
u64 host1x_get_dma_mask(struct host1x *host1x)
{
        return host1x->info->dma_mask;
}
EXPORT_SYMBOL(host1x_get_dma_mask);

MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
MODULE_AUTHOR("Terje Bergstrom <tbergstrom@nvidia.com>");
MODULE_DESCRIPTION("Host1x driver for Tegra products");
MODULE_LICENSE("GPL");