// SPDX-License-Identifier: GPL-2.0-only
/*
 * Driver for MPC52xx processor BestComm peripheral controller
 *
 * Copyright (C) 2006-2007 Sylvain Munaut <tnt@246tNt.com>
 * Copyright (C) 2005      Varma Electronics Oy,
 *                         ( by Andrey Volkov <avolkov@varma-el.com> )
 * Copyright (C) 2003-2004 MontaVista, Software, Inc.
 *                         ( by Dale Farnsworth <dfarnsworth@mvista.com> )
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/mpc52xx.h>

#include <linux/fsl/bestcomm/sram.h>
#include <linux/fsl/bestcomm/bestcomm_priv.h>
#include "linux/fsl/bestcomm/bestcomm.h"

#define DRIVER_NAME "bestcomm-core"

/* MPC5200 device tree match tables */
static const struct of_device_id mpc52xx_sram_ids[] = {
        { .compatible = "fsl,mpc5200-sram", },
        { .compatible = "mpc5200-sram", },
        {}
};


struct bcom_engine *bcom_eng = NULL;
EXPORT_SYMBOL_GPL(bcom_eng);    /* needed for inline functions */

/* ======================================================================== */
/* Public and private API                                                   */
/* ======================================================================== */

/* Private API */

struct bcom_task *
bcom_task_alloc(int bd_count, int bd_size, int priv_size)
{
        int i, tasknum = -1;
        struct bcom_task *tsk;

        /* Don't try to do anything if bestcomm init failed */
        if (!bcom_eng)
                return NULL;

        /* Get and reserve a task num */
        spin_lock(&bcom_eng->lock);

        for (i=0; i<BCOM_MAX_TASKS; i++)
                if (!bcom_eng->tdt[i].stop) {   /* we use stop as a marker */
                        bcom_eng->tdt[i].stop = 0xfffffffful; /* dummy addr */
                        tasknum = i;
                        break;
                }

        spin_unlock(&bcom_eng->lock);

        if (tasknum < 0)
                return NULL;

        /* Allocate our structure */
        tsk = kzalloc(sizeof(struct bcom_task) + priv_size, GFP_KERNEL);
        if (!tsk)
                goto error;

        tsk->tasknum = tasknum;
        if (priv_size)
                tsk->priv = (void*)tsk + sizeof(struct bcom_task);

        /* Get IRQ of that task */
        tsk->irq = irq_of_parse_and_map(bcom_eng->ofnode, tsk->tasknum);
        if (!tsk->irq)
                goto error;

        /* Init the BDs, if needed */
        if (bd_count) {
                tsk->cookie = kmalloc_array(bd_count, sizeof(void *),
                                            GFP_KERNEL);
                if (!tsk->cookie)
                        goto error;

                tsk->bd = bcom_sram_alloc(bd_count * bd_size, 4, &tsk->bd_pa);
                if (!tsk->bd)
                        goto error;
                memset_io(tsk->bd, 0x00, bd_count * bd_size);

                tsk->num_bd = bd_count;
                tsk->bd_size = bd_size;
        }

        return tsk;

error:
        if (tsk) {
                if (tsk->irq)
                        irq_dispose_mapping(tsk->irq);
                bcom_sram_free(tsk->bd);
                kfree(tsk->cookie);
                kfree(tsk);
        }

        bcom_eng->tdt[tasknum].stop = 0;

        return NULL;
}
EXPORT_SYMBOL_GPL(bcom_task_alloc);

void
bcom_task_free(struct bcom_task *tsk)
{
        /* Stop the task */
        bcom_disable_task(tsk->tasknum);

        /* Clear TDT */
        bcom_eng->tdt[tsk->tasknum].start = 0;
        bcom_eng->tdt[tsk->tasknum].stop  = 0;

        /* Free everything */
        irq_dispose_mapping(tsk->irq);
        bcom_sram_free(tsk->bd);
        kfree(tsk->cookie);
        kfree(tsk);
}
EXPORT_SYMBOL_GPL(bcom_task_free);

int
bcom_load_image(int task, u32 *task_image)
{
        struct bcom_task_header *hdr = (struct bcom_task_header *)task_image;
        struct bcom_tdt *tdt;
        u32 *desc, *var, *inc;
        u32 *desc_src, *var_src, *inc_src;

        /* Safety checks */
        if (hdr->magic != BCOM_TASK_MAGIC) {
                printk(KERN_ERR DRIVER_NAME
                        ": Trying to load invalid microcode\n");
                return -EINVAL;
        }

        if ((task < 0) || (task >= BCOM_MAX_TASKS)) {
                printk(KERN_ERR DRIVER_NAME
                        ": Trying to load invalid task %d\n", task);
                return -EINVAL;
        }

        /* Initial load or reload */
        tdt = &bcom_eng->tdt[task];

        if (tdt->start) {
                desc = bcom_task_desc(task);
                if (hdr->desc_size != bcom_task_num_descs(task)) {
                        printk(KERN_ERR DRIVER_NAME
                                ": Trying to reload wrong task image "
                                "(%d size %d/%d)!\n",
                                task,
                                hdr->desc_size,
                                bcom_task_num_descs(task));
                        return -EINVAL;
                }
        } else {
                phys_addr_t start_pa;

                desc = bcom_sram_alloc(hdr->desc_size * sizeof(u32), 4, &start_pa);
                if (!desc)
                        return -ENOMEM;

                tdt->start = start_pa;
                tdt->stop = start_pa + ((hdr->desc_size-1) * sizeof(u32));
        }

        var = bcom_task_var(task);
        inc = bcom_task_inc(task);

        /* Clear & copy */
        memset_io(var, 0x00, BCOM_VAR_SIZE);
        memset_io(inc, 0x00, BCOM_INC_SIZE);

        desc_src = (u32 *)(hdr + 1);
        var_src = desc_src + hdr->desc_size;
        inc_src = var_src + hdr->var_size;

        memcpy_toio(desc, desc_src, hdr->desc_size * sizeof(u32));
        memcpy_toio(var + hdr->first_var, var_src, hdr->var_size * sizeof(u32));
        memcpy_toio(inc, inc_src, hdr->inc_size * sizeof(u32));

        return 0;
}
EXPORT_SYMBOL_GPL(bcom_load_image);

void
bcom_set_initiator(int task, int initiator)
{
        int i;
        int num_descs;
        u32 *desc;
        int next_drd_has_initiator;

        bcom_set_tcr_initiator(task, initiator);

        /* Just setting tcr is apparently not enough due to some problem */
        /* with it. So we just go thru all the microcode and replace in  */
        /* the DRD directly */

        desc = bcom_task_desc(task);
        next_drd_has_initiator = 1;
        num_descs = bcom_task_num_descs(task);

        for (i=0; i<num_descs; i++, desc++) {
                if (!bcom_desc_is_drd(*desc))
                        continue;
                if (next_drd_has_initiator)
                        if (bcom_desc_initiator(*desc) != BCOM_INITIATOR_ALWAYS)
                                bcom_set_desc_initiator(desc, initiator);
                next_drd_has_initiator = !bcom_drd_is_extended(*desc);
        }
}
EXPORT_SYMBOL_GPL(bcom_set_initiator);


/* Public API */

void
bcom_enable(struct bcom_task *tsk)
{
        bcom_enable_task(tsk->tasknum);
}
EXPORT_SYMBOL_GPL(bcom_enable);

void
bcom_disable(struct bcom_task *tsk)
{
        bcom_disable_task(tsk->tasknum);
}
EXPORT_SYMBOL_GPL(bcom_disable);


/* ======================================================================== */
/* Engine init/cleanup                                                      */
/* ======================================================================== */

/* Function Descriptor table */
/* this will need to be updated if Freescale changes their task code FDT */
static u32 fdt_ops[] = {
        0xa0045670,     /* FDT[48] - load_acc()   */
        0x80045670,     /* FDT[49] - unload_acc() */
        0x21800000,     /* FDT[50] - and()        */
        0x21e00000,     /* FDT[51] - or()         */
        0x21500000,     /* FDT[52] - xor()        */
        0x21400000,     /* FDT[53] - andn()       */
        0x21500000,     /* FDT[54] - not()        */
        0x20400000,     /* FDT[55] - add()        */
        0x20500000,     /* FDT[56] - sub()        */
        0x20800000,     /* FDT[57] - lsh()        */
        0x20a00000,     /* FDT[58] - rsh()        */
        0xc0170000,     /* FDT[59] - crc8()       */
        0xc0145670,     /* FDT[60] - crc16()      */
        0xc0345670,     /* FDT[61] - crc32()      */
        0xa0076540,     /* FDT[62] - endian32()   */
        0xa0000760,     /* FDT[63] - endian16()   */
};


static int bcom_engine_init(void)
{
        int task;
        phys_addr_t tdt_pa, ctx_pa, var_pa, fdt_pa;
        unsigned int tdt_size, ctx_size, var_size, fdt_size;

        /* Allocate & clear SRAM zones for FDT, TDTs, contexts and vars/incs */
        tdt_size = BCOM_MAX_TASKS * sizeof(struct bcom_tdt);
        ctx_size = BCOM_MAX_TASKS * BCOM_CTX_SIZE;
        var_size = BCOM_MAX_TASKS * (BCOM_VAR_SIZE + BCOM_INC_SIZE);
        fdt_size = BCOM_FDT_SIZE;

        bcom_eng->tdt = bcom_sram_alloc(tdt_size, sizeof(u32), &tdt_pa);
        bcom_eng->ctx = bcom_sram_alloc(ctx_size, BCOM_CTX_ALIGN, &ctx_pa);
        bcom_eng->var = bcom_sram_alloc(var_size, BCOM_VAR_ALIGN, &var_pa);
        bcom_eng->fdt = bcom_sram_alloc(fdt_size, BCOM_FDT_ALIGN, &fdt_pa);

        if (!bcom_eng->tdt || !bcom_eng->ctx || !bcom_eng->var || !bcom_eng->fdt) {
                printk(KERN_ERR "DMA: SRAM alloc failed in engine init !\n");

                bcom_sram_free(bcom_eng->tdt);
                bcom_sram_free(bcom_eng->ctx);
                bcom_sram_free(bcom_eng->var);
                bcom_sram_free(bcom_eng->fdt);

                return -ENOMEM;
        }

        memset_io(bcom_eng->tdt, 0x00, tdt_size);
        memset_io(bcom_eng->ctx, 0x00, ctx_size);
        memset_io(bcom_eng->var, 0x00, var_size);
        memset_io(bcom_eng->fdt, 0x00, fdt_size);

        /* Copy the FDT for the EU#3 */
        memcpy_toio(&bcom_eng->fdt[48], fdt_ops, sizeof(fdt_ops));

        /* Initialize Task base structure */
        for (task=0; task<BCOM_MAX_TASKS; task++)
        {
                out_be16(&bcom_eng->regs->tcr[task], 0);
                out_8(&bcom_eng->regs->ipr[task], 0);

                bcom_eng->tdt[task].context     = ctx_pa;
                bcom_eng->tdt[task].var = var_pa;
                bcom_eng->tdt[task].fdt = fdt_pa;

                var_pa += BCOM_VAR_SIZE + BCOM_INC_SIZE;
                ctx_pa += BCOM_CTX_SIZE;
        }

        out_be32(&bcom_eng->regs->taskBar, tdt_pa);

        /* Init 'always' initiator */
        out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ALWAYS], BCOM_IPR_ALWAYS);

        /* Disable COMM Bus Prefetch on the original 5200; it's broken */
        if ((mfspr(SPRN_SVR) & MPC5200_SVR_MASK) == MPC5200_SVR)
                bcom_disable_prefetch();

        /* Init lock */
        spin_lock_init(&bcom_eng->lock);

        return 0;
}

static void
bcom_engine_cleanup(void)
{
        int task;

        /* Stop all tasks */
        for (task=0; task<BCOM_MAX_TASKS; task++)
        {
                out_be16(&bcom_eng->regs->tcr[task], 0);
                out_8(&bcom_eng->regs->ipr[task], 0);
        }

        out_be32(&bcom_eng->regs->taskBar, 0ul);

        /* Release the SRAM zones */
        bcom_sram_free(bcom_eng->tdt);
        bcom_sram_free(bcom_eng->ctx);
        bcom_sram_free(bcom_eng->var);
        bcom_sram_free(bcom_eng->fdt);
}


/* ======================================================================== */
/* OF platform driver                                                       */
/* ======================================================================== */

static int mpc52xx_bcom_probe(struct platform_device *op)
{
        struct device_node *ofn_sram;
        struct resource res_bcom;

        int rv;

        /* Inform user we're ok so far */
        printk(KERN_INFO "DMA: MPC52xx BestComm driver\n");

        /* Get the bestcomm node */
        of_node_get(op->dev.of_node);

        /* Prepare SRAM */
        ofn_sram = of_find_matching_node(NULL, mpc52xx_sram_ids);
        if (!ofn_sram) {
                printk(KERN_ERR DRIVER_NAME ": "
                        "No SRAM found in device tree\n");
                rv = -ENODEV;
                goto error_ofput;
        }
        rv = bcom_sram_init(ofn_sram, DRIVER_NAME);
        of_node_put(ofn_sram);

        if (rv) {
                printk(KERN_ERR DRIVER_NAME ": "
                        "Error in SRAM init\n");
                goto error_ofput;
        }

        /* Get a clean struct */
        bcom_eng = kzalloc_obj(struct bcom_engine);
        if (!bcom_eng) {
                rv = -ENOMEM;
                goto error_sramclean;
        }

        /* Save the node */
        bcom_eng->ofnode = op->dev.of_node;

        /* Get, reserve & map io */
        if (of_address_to_resource(op->dev.of_node, 0, &res_bcom)) {
                printk(KERN_ERR DRIVER_NAME ": "
                        "Can't get resource\n");
                rv = -EINVAL;
                goto error_sramclean;
        }

        if (!request_mem_region(res_bcom.start, resource_size(&res_bcom),
                                DRIVER_NAME)) {
                printk(KERN_ERR DRIVER_NAME ": "
                        "Can't request registers region\n");
                rv = -EBUSY;
                goto error_sramclean;
        }

        bcom_eng->regs_base = res_bcom.start;
        bcom_eng->regs = ioremap(res_bcom.start, sizeof(struct mpc52xx_sdma));
        if (!bcom_eng->regs) {
                printk(KERN_ERR DRIVER_NAME ": "
                        "Can't map registers\n");
                rv = -ENOMEM;
                goto error_release;
        }

        /* Now, do the real init */
        rv = bcom_engine_init();
        if (rv)
                goto error_unmap;

        /* Done ! */
        printk(KERN_INFO "DMA: MPC52xx BestComm engine @%08lx ok !\n",
                (long)bcom_eng->regs_base);

        return 0;

        /* Error path */
error_unmap:
        iounmap(bcom_eng->regs);
error_release:
        release_mem_region(res_bcom.start, sizeof(struct mpc52xx_sdma));
error_sramclean:
        kfree(bcom_eng);
        bcom_sram_cleanup();
error_ofput:
        of_node_put(op->dev.of_node);

        printk(KERN_ERR "DMA: MPC52xx BestComm init failed !\n");

        return rv;
}


static void mpc52xx_bcom_remove(struct platform_device *op)
{
        /* Clean up the engine */
        bcom_engine_cleanup();

        /* Cleanup SRAM */
        bcom_sram_cleanup();

        /* Release regs */
        iounmap(bcom_eng->regs);
        release_mem_region(bcom_eng->regs_base, sizeof(struct mpc52xx_sdma));

        /* Release the node */
        of_node_put(bcom_eng->ofnode);

        /* Release memory */
        kfree(bcom_eng);
        bcom_eng = NULL;
}

static const struct of_device_id mpc52xx_bcom_of_match[] = {
        { .compatible = "fsl,mpc5200-bestcomm", },
        { .compatible = "mpc5200-bestcomm", },
        {},
};

MODULE_DEVICE_TABLE(of, mpc52xx_bcom_of_match);


static struct platform_driver mpc52xx_bcom_of_platform_driver = {
        .probe          = mpc52xx_bcom_probe,
        .remove         = mpc52xx_bcom_remove,
        .driver = {
                .name = DRIVER_NAME,
                .of_match_table = mpc52xx_bcom_of_match,
        },
};


/* ======================================================================== */
/* Module                                                                   */
/* ======================================================================== */

static int __init
mpc52xx_bcom_init(void)
{
        return platform_driver_register(&mpc52xx_bcom_of_platform_driver);
}

static void __exit
mpc52xx_bcom_exit(void)
{
        platform_driver_unregister(&mpc52xx_bcom_of_platform_driver);
}

/* If we're not a module, we must make sure everything is setup before  */
/* anyone tries to use us ... that's why we use subsys_initcall instead */
/* of module_init. */
subsys_initcall(mpc52xx_bcom_init);
module_exit(mpc52xx_bcom_exit);

MODULE_DESCRIPTION("Freescale MPC52xx BestComm DMA");
MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
MODULE_AUTHOR("Andrey Volkov <avolkov@varma-el.com>");
MODULE_AUTHOR("Dale Farnsworth <dfarnsworth@mvista.com>");
MODULE_LICENSE("GPL v2");