// SPDX-License-Identifier: GPL-2.0-only
/*
 * TI K3 Remote Processor(s) driver common code
 *
 * Refactored out of ti_k3_r5_remoteproc.c, ti_k3_dsp_remoteproc.c and
 * ti_k3_m4_remoteproc.c.
 *
 * ti_k3_r5_remoteproc.c:
 * Copyright (C) 2017-2022 Texas Instruments Incorporated - https://www.ti.com/
 *      Suman Anna <s-anna@ti.com>
 *
 * ti_k3_dsp_remoteproc.c:
 * Copyright (C) 2018-2022 Texas Instruments Incorporated - https://www.ti.com/
 *      Suman Anna <s-anna@ti.com>
 *
 * ti_k3_m4_remoteproc.c:
 * Copyright (C) 2021-2024 Texas Instruments Incorporated - https://www.ti.com/
 *      Hari Nagalla <hnagalla@ti.com>
 */

#include <linux/io.h>
#include <linux/mailbox_client.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_reserved_mem.h>
#include <linux/omap-mailbox.h>
#include <linux/platform_device.h>
#include <linux/remoteproc.h>
#include <linux/reset.h>
#include <linux/slab.h>

#include "omap_remoteproc.h"
#include "remoteproc_internal.h"
#include "ti_sci_proc.h"
#include "ti_k3_common.h"

/**
 * k3_rproc_mbox_callback() - inbound mailbox message handler
 * @client: mailbox client pointer used for requesting the mailbox channel
 * @data: mailbox payload
 *
 * This handler is invoked by the K3 mailbox driver whenever a mailbox
 * message is received. Usually, the mailbox payload simply contains
 * the index of the virtqueue that is kicked by the remote processor,
 * and we let remoteproc core handle it.
 *
 * In addition to virtqueue indices, we also have some out-of-band values
 * that indicate different events. Those values are deliberately very
 * large so they don't coincide with virtqueue indices.
 */
void k3_rproc_mbox_callback(struct mbox_client *client, void *data)
{
        struct k3_rproc *kproc = container_of(client, struct k3_rproc, client);
        struct device *dev = kproc->rproc->dev.parent;
        struct rproc *rproc = kproc->rproc;
        u32 msg = (u32)(uintptr_t)(data);

        dev_dbg(dev, "mbox msg: 0x%x\n", msg);

        switch (msg) {
        case RP_MBOX_CRASH:
                /*
                 * remoteproc detected an exception, but error recovery is not
                 * supported. So, just log this for now
                 */
                dev_err(dev, "K3 rproc %s crashed\n", rproc->name);
                break;
        case RP_MBOX_ECHO_REPLY:
                dev_info(dev, "received echo reply from %s\n", rproc->name);
                break;
        default:
                /* silently handle all other valid messages */
                if (msg >= RP_MBOX_READY && msg < RP_MBOX_END_MSG)
                        return;
                if (msg > rproc->max_notifyid) {
                        dev_dbg(dev, "dropping unknown message 0x%x", msg);
                        return;
                }
                /* msg contains the index of the triggered vring */
                if (rproc_vq_interrupt(rproc, msg) == IRQ_NONE)
                        dev_dbg(dev, "no message was found in vqid %d\n", msg);
        }
}
EXPORT_SYMBOL_GPL(k3_rproc_mbox_callback);

/*
 * Kick the remote processor to notify about pending unprocessed messages.
 * The vqid usage is not used and is inconsequential, as the kick is performed
 * through a simulated GPIO (a bit in an IPC interrupt-triggering register),
 * the remote processor is expected to process both its Tx and Rx virtqueues.
 */
void k3_rproc_kick(struct rproc *rproc, int vqid)
{
        struct k3_rproc *kproc = rproc->priv;
        struct device *dev = kproc->dev;
        u32 msg = (u32)vqid;
        int ret;

        /*
         * Send the index of the triggered virtqueue in the mailbox payload.
         * NOTE: msg is cast to uintptr_t to prevent compiler warnings when
         * void* is 64bit. It is safely cast back to u32 in the mailbox driver.
         */
        ret = mbox_send_message(kproc->mbox, (void *)(uintptr_t)msg);
        if (ret < 0)
                dev_err(dev, "failed to send mailbox message, status = %d\n",
                        ret);
}
EXPORT_SYMBOL_GPL(k3_rproc_kick);

/* Put the remote processor into reset */
int k3_rproc_reset(struct k3_rproc *kproc)
{
        struct device *dev = kproc->dev;
        int ret;

        if (kproc->data->uses_lreset) {
                ret = reset_control_assert(kproc->reset);
                if (ret)
                        dev_err(dev, "local-reset assert failed (%pe)\n", ERR_PTR(ret));
        } else {
                ret = kproc->ti_sci->ops.dev_ops.put_device(kproc->ti_sci,
                                                            kproc->ti_sci_id);
                if (ret)
                        dev_err(dev, "module-reset assert failed (%pe)\n", ERR_PTR(ret));
        }

        return ret;
}
EXPORT_SYMBOL_GPL(k3_rproc_reset);

/* Release the remote processor from reset */
int k3_rproc_release(struct k3_rproc *kproc)
{
        struct device *dev = kproc->dev;
        int ret;

        if (kproc->data->uses_lreset) {
                ret = reset_control_deassert(kproc->reset);
                if (ret) {
                        dev_err(dev, "local-reset deassert failed, (%pe)\n", ERR_PTR(ret));
                        if (kproc->ti_sci->ops.dev_ops.put_device(kproc->ti_sci,
                                                                  kproc->ti_sci_id))
                                dev_warn(dev, "module-reset assert back failed\n");
                }
        } else {
                ret = kproc->ti_sci->ops.dev_ops.get_device(kproc->ti_sci,
                                                            kproc->ti_sci_id);
                if (ret)
                        dev_err(dev, "module-reset deassert failed (%pe)\n", ERR_PTR(ret));
        }

        return ret;
}
EXPORT_SYMBOL_GPL(k3_rproc_release);

static void k3_rproc_free_channel(void *data)
{
        struct k3_rproc *kproc = data;

        mbox_free_channel(kproc->mbox);
}

int k3_rproc_request_mbox(struct rproc *rproc)
{
        struct k3_rproc *kproc = rproc->priv;
        struct mbox_client *client = &kproc->client;
        struct device *dev = kproc->dev;
        int ret;

        client->dev = dev;
        client->tx_done = NULL;
        client->rx_callback = k3_rproc_mbox_callback;
        client->tx_block = false;
        client->knows_txdone = false;

        kproc->mbox = mbox_request_channel(client, 0);
        if (IS_ERR(kproc->mbox))
                return dev_err_probe(dev, PTR_ERR(kproc->mbox),
                                     "mbox_request_channel failed\n");

        ret = devm_add_action_or_reset(dev, k3_rproc_free_channel, kproc);
        if (ret)
                return ret;

        return 0;
}
EXPORT_SYMBOL_GPL(k3_rproc_request_mbox);

/*
 * The K3 DSP and M4 cores have a local reset that affects only the CPU, and a
 * generic module reset that powers on the device and allows the internal
 * memories to be accessed while the local reset is asserted. This function is
 * used to release the global reset on remote cores to allow loading into the
 * internal RAMs. The .prepare() ops is invoked by remoteproc core before any
 * firmware loading, and is followed by the .start() ops after loading to
 * actually let the remote cores to run.
 */
int k3_rproc_prepare(struct rproc *rproc)
{
        struct k3_rproc *kproc = rproc->priv;
        struct device *dev = kproc->dev;
        int ret;

        /* If the core is running already no need to deassert the module reset */
        if (rproc->state == RPROC_DETACHED)
                return 0;

        /*
         * Ensure the local reset is asserted so the core doesn't
         * execute bogus code when the module reset is released.
         */
        if (kproc->data->uses_lreset) {
                ret = k3_rproc_reset(kproc);
                if (ret)
                        return ret;

                ret = reset_control_status(kproc->reset);
                if (ret <= 0) {
                        dev_err(dev, "local reset still not asserted\n");
                        return ret;
                }
        }

        ret = kproc->ti_sci->ops.dev_ops.get_device(kproc->ti_sci,
                                                    kproc->ti_sci_id);
        if (ret) {
                dev_err(dev, "could not deassert module-reset for internal RAM loading\n");
                return ret;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(k3_rproc_prepare);

/*
 * This function implements the .unprepare() ops and performs the complimentary
 * operations to that of the .prepare() ops. The function is used to assert the
 * global reset on applicable K3 DSP and M4 cores. This completes the second
 * portion of powering down the remote core. The cores themselves are only
 * halted in the .stop() callback through the local reset, and the .unprepare()
 * ops is invoked by the remoteproc core after the remoteproc is stopped to
 * balance the global reset.
 */
int k3_rproc_unprepare(struct rproc *rproc)
{
        struct k3_rproc *kproc = rproc->priv;
        struct device *dev = kproc->dev;
        int ret;

        /* If the core is going to be detached do not assert the module reset */
        if (rproc->state == RPROC_DETACHED)
                return 0;

        ret = kproc->ti_sci->ops.dev_ops.put_device(kproc->ti_sci,
                                                    kproc->ti_sci_id);
        if (ret) {
                dev_err(dev, "module-reset assert failed\n");
                return ret;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(k3_rproc_unprepare);

/*
 * Power up the remote processor.
 *
 * This function will be invoked only after the firmware for this rproc
 * was loaded, parsed successfully, and all of its resource requirements
 * were met. This callback is invoked only in remoteproc mode.
 */
int k3_rproc_start(struct rproc *rproc)
{
        struct k3_rproc *kproc = rproc->priv;

        return k3_rproc_release(kproc);
}
EXPORT_SYMBOL_GPL(k3_rproc_start);

/*
 * Stop the remote processor.
 *
 * This function puts the remote processor into reset, and finishes processing
 * of any pending messages. This callback is invoked only in remoteproc mode.
 */
int k3_rproc_stop(struct rproc *rproc)
{
        struct k3_rproc *kproc = rproc->priv;

        return k3_rproc_reset(kproc);
}
EXPORT_SYMBOL_GPL(k3_rproc_stop);

/*
 * Attach to a running remote processor (IPC-only mode)
 *
 * The rproc attach callback is a NOP. The remote processor is already booted,
 * and all required resources have been acquired during probe routine, so there
 * is no need to issue any TI-SCI commands to boot the remote cores in IPC-only
 * mode. This callback is invoked only in IPC-only mode and exists because
 * rproc_validate() checks for its existence.
 */
int k3_rproc_attach(struct rproc *rproc) { return 0; }
EXPORT_SYMBOL_GPL(k3_rproc_attach);

/*
 * Detach from a running remote processor (IPC-only mode)
 *
 * The rproc detach callback is a NOP. The remote processor is not stopped and
 * will be left in booted state in IPC-only mode. This callback is invoked only
 * in IPC-only mode and exists for sanity sake
 */
int k3_rproc_detach(struct rproc *rproc) { return 0; }
EXPORT_SYMBOL_GPL(k3_rproc_detach);

/*
 * This function implements the .get_loaded_rsc_table() callback and is used
 * to provide the resource table for a booted remote processor in IPC-only
 * mode. The remote processor firmwares follow a design-by-contract approach
 * and are expected to have the resource table at the base of the DDR region
 * reserved for firmware usage. This provides flexibility for the remote
 * processor to be booted by different bootloaders that may or may not have the
 * ability to publish the resource table address and size through a DT
 * property.
 */
struct resource_table *k3_get_loaded_rsc_table(struct rproc *rproc,
                                               size_t *rsc_table_sz)
{
        struct k3_rproc *kproc = rproc->priv;
        struct device *dev = kproc->dev;

        if (!kproc->rmem[0].cpu_addr) {
                dev_err(dev, "memory-region #1 does not exist, loaded rsc table can't be found");
                return ERR_PTR(-ENOMEM);
        }

        /*
         * NOTE: The resource table size is currently hard-coded to a maximum
         * of 256 bytes. The most common resource table usage for K3 firmwares
         * is to only have the vdev resource entry and an optional trace entry.
         * The exact size could be computed based on resource table address, but
         * the hard-coded value suffices to support the IPC-only mode.
         */
        *rsc_table_sz = 256;
        return (__force struct resource_table *)kproc->rmem[0].cpu_addr;
}
EXPORT_SYMBOL_GPL(k3_get_loaded_rsc_table);

/*
 * Custom function to translate a remote processor device address (internal
 * RAMs only) to a kernel virtual address.  The remote processors can access
 * their RAMs at either an internal address visible only from a remote
 * processor, or at the SoC-level bus address. Both these addresses need to be
 * looked through for translation. The translated addresses can be used either
 * by the remoteproc core for loading (when using kernel remoteproc loader), or
 * by any rpmsg bus drivers.
 */
void *k3_rproc_da_to_va(struct rproc *rproc, u64 da, size_t len, bool *is_iomem)
{
        struct k3_rproc *kproc = rproc->priv;
        void __iomem *va = NULL;
        phys_addr_t bus_addr;
        u32 dev_addr, offset;
        size_t size;
        int i;

        if (len == 0)
                return NULL;

        for (i = 0; i < kproc->num_mems; i++) {
                bus_addr = kproc->mem[i].bus_addr;
                dev_addr = kproc->mem[i].dev_addr;
                size = kproc->mem[i].size;

                /* handle rproc-view addresses */
                if (da >= dev_addr && ((da + len) <= (dev_addr + size))) {
                        offset = da - dev_addr;
                        va = kproc->mem[i].cpu_addr + offset;
                        return (__force void *)va;
                }

                /* handle SoC-view addresses */
                if (da >= bus_addr && (da + len) <= (bus_addr + size)) {
                        offset = da - bus_addr;
                        va = kproc->mem[i].cpu_addr + offset;
                        return (__force void *)va;
                }
        }

        /* handle static DDR reserved memory regions */
        for (i = 0; i < kproc->num_rmems; i++) {
                dev_addr = kproc->rmem[i].dev_addr;
                size = kproc->rmem[i].size;

                if (da >= dev_addr && ((da + len) <= (dev_addr + size))) {
                        offset = da - dev_addr;
                        va = kproc->rmem[i].cpu_addr + offset;
                        return (__force void *)va;
                }
        }

        return NULL;
}
EXPORT_SYMBOL_GPL(k3_rproc_da_to_va);

int k3_rproc_of_get_memories(struct platform_device *pdev,
                             struct k3_rproc *kproc)
{
        const struct k3_rproc_dev_data *data = kproc->data;
        struct device *dev = &pdev->dev;
        struct resource *res;
        int num_mems = 0;
        int i;

        num_mems = data->num_mems;
        kproc->mem = devm_kcalloc(kproc->dev, num_mems,
                                  sizeof(*kproc->mem), GFP_KERNEL);
        if (!kproc->mem)
                return -ENOMEM;

        for (i = 0; i < num_mems; i++) {
                res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
                                                   data->mems[i].name);
                if (!res) {
                        dev_err(dev, "found no memory resource for %s\n",
                                data->mems[i].name);
                        return -EINVAL;
                }
                if (!devm_request_mem_region(dev, res->start,
                                             resource_size(res),
                                             dev_name(dev))) {
                        dev_err(dev, "could not request %s region for resource\n",
                                data->mems[i].name);
                        return -EBUSY;
                }

                kproc->mem[i].cpu_addr = devm_ioremap_wc(dev, res->start,
                                                         resource_size(res));
                if (!kproc->mem[i].cpu_addr) {
                        dev_err(dev, "failed to map %s memory\n",
                                data->mems[i].name);
                        return -ENOMEM;
                }
                kproc->mem[i].bus_addr = res->start;
                kproc->mem[i].dev_addr = data->mems[i].dev_addr;
                kproc->mem[i].size = resource_size(res);

                dev_dbg(dev, "memory %8s: bus addr %pa size 0x%zx va %p da 0x%x\n",
                        data->mems[i].name, &kproc->mem[i].bus_addr,
                        kproc->mem[i].size, kproc->mem[i].cpu_addr,
                        kproc->mem[i].dev_addr);
        }
        kproc->num_mems = num_mems;

        return 0;
}
EXPORT_SYMBOL_GPL(k3_rproc_of_get_memories);

void k3_mem_release(void *data)
{
        struct device *dev = data;

        of_reserved_mem_device_release(dev);
}
EXPORT_SYMBOL_GPL(k3_mem_release);

int k3_reserved_mem_init(struct k3_rproc *kproc)
{
        struct device *dev = kproc->dev;
        struct device_node *np = dev->of_node;
        int num_rmems;
        int ret, i;

        num_rmems = of_reserved_mem_region_count(np);
        if (num_rmems < 0) {
                dev_err(dev, "device does not reserved memory regions (%d)\n",
                        num_rmems);
                return -EINVAL;
        }
        if (num_rmems < 2) {
                dev_err(dev, "device needs at least two memory regions to be defined, num = %d\n",
                        num_rmems);
                return -EINVAL;
        }

        /* use reserved memory region 0 for vring DMA allocations */
        ret = of_reserved_mem_device_init_by_idx(dev, np, 0);
        if (ret) {
                dev_err(dev, "device cannot initialize DMA pool (%d)\n", ret);
                return ret;
        }
        ret = devm_add_action_or_reset(dev, k3_mem_release, dev);
        if (ret)
                return ret;

        num_rmems--;
        kproc->rmem = devm_kcalloc(dev, num_rmems, sizeof(*kproc->rmem), GFP_KERNEL);
        if (!kproc->rmem)
                return -ENOMEM;

        /* use remaining reserved memory regions for static carveouts */
        for (i = 0; i < num_rmems; i++) {
                struct resource res;

                ret = of_reserved_mem_region_to_resource(np, i + 1, &res);
                if (ret)
                        return ret;

                kproc->rmem[i].bus_addr = res.start;
                /* 64-bit address regions currently not supported */
                kproc->rmem[i].dev_addr = (u32)res.start;
                kproc->rmem[i].size = resource_size(&res);
                kproc->rmem[i].cpu_addr = devm_ioremap_resource_wc(dev, &res);
                if (!kproc->rmem[i].cpu_addr) {
                        dev_err(dev, "failed to map reserved memory#%d at %pR\n",
                                i + 1, &res);
                        return -ENOMEM;
                }

                dev_dbg(dev, "reserved memory%d: bus addr %pa size 0x%zx va %p da 0x%x\n",
                        i + 1, &kproc->rmem[i].bus_addr,
                        kproc->rmem[i].size, kproc->rmem[i].cpu_addr,
                        kproc->rmem[i].dev_addr);
        }
        kproc->num_rmems = num_rmems;

        return 0;
}
EXPORT_SYMBOL_GPL(k3_reserved_mem_init);

void k3_release_tsp(void *data)
{
        struct ti_sci_proc *tsp = data;

        ti_sci_proc_release(tsp);
}
EXPORT_SYMBOL_GPL(k3_release_tsp);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("TI K3 common Remoteproc code");