root/drivers/soc/ti/knav_qmss_acc.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Keystone accumulator queue manager
 *
 * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com
 * Author:      Sandeep Nair <sandeep_n@ti.com>
 *              Cyril Chemparathy <cyril@ti.com>
 *              Santosh Shilimkar <santosh.shilimkar@ti.com>
 */

#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/soc/ti/knav_qmss.h>

#include "knav_qmss.h"

#define knav_range_offset_to_inst(kdev, range, q)       \
        (range->queue_base_inst + (q << kdev->inst_shift))

static void __knav_acc_notify(struct knav_range_info *range,
                                struct knav_acc_channel *acc)
{
        struct knav_device *kdev = range->kdev;
        struct knav_queue_inst *inst;
        int range_base, queue;

        range_base = kdev->base_id + range->queue_base;

        if (range->flags & RANGE_MULTI_QUEUE) {
                for (queue = 0; queue < range->num_queues; queue++) {
                        inst = knav_range_offset_to_inst(kdev, range,
                                                                queue);
                        if (inst->notify_needed) {
                                inst->notify_needed = 0;
                                dev_dbg(kdev->dev, "acc-irq: notifying %d\n",
                                        range_base + queue);
                                knav_queue_notify(inst);
                        }
                }
        } else {
                queue = acc->channel - range->acc_info.start_channel;
                inst = knav_range_offset_to_inst(kdev, range, queue);
                dev_dbg(kdev->dev, "acc-irq: notifying %d\n",
                        range_base + queue);
                knav_queue_notify(inst);
        }
}

static int knav_acc_set_notify(struct knav_range_info *range,
                                struct knav_queue_inst *kq,
                                bool enabled)
{
        struct knav_pdsp_info *pdsp = range->acc_info.pdsp;
        struct knav_device *kdev = range->kdev;
        u32 mask, offset;

        /*
         * when enabling, we need to re-trigger an interrupt if we
         * have descriptors pending
         */
        if (!enabled || atomic_read(&kq->desc_count) <= 0)
                return 0;

        kq->notify_needed = 1;
        atomic_inc(&kq->acc->retrigger_count);
        mask = BIT(kq->acc->channel % 32);
        offset = ACC_INTD_OFFSET_STATUS(kq->acc->channel);
        dev_dbg(kdev->dev, "setup-notify: re-triggering irq for %s\n",
                kq->acc->name);
        writel_relaxed(mask, pdsp->intd + offset);
        return 0;
}

static irqreturn_t knav_acc_int_handler(int irq, void *_instdata)
{
        struct knav_acc_channel *acc;
        struct knav_queue_inst *kq = NULL;
        struct knav_range_info *range;
        struct knav_pdsp_info *pdsp;
        struct knav_acc_info *info;
        struct knav_device *kdev;

        u32 *list, *list_cpu, val, idx, notifies;
        int range_base, channel, queue = 0;
        dma_addr_t list_dma;

        range = _instdata;
        info  = &range->acc_info;
        kdev  = range->kdev;
        pdsp  = range->acc_info.pdsp;
        acc   = range->acc;

        range_base = kdev->base_id + range->queue_base;
        if ((range->flags & RANGE_MULTI_QUEUE) == 0) {
                for (queue = 0; queue < range->num_irqs; queue++)
                        if (range->irqs[queue].irq == irq)
                                break;
                kq = knav_range_offset_to_inst(kdev, range, queue);
                acc += queue;
        }

        channel = acc->channel;
        list_dma = acc->list_dma[acc->list_index];
        list_cpu = acc->list_cpu[acc->list_index];
        dev_dbg(kdev->dev, "acc-irq: channel %d, list %d, virt %p, dma %pad\n",
                channel, acc->list_index, list_cpu, &list_dma);
        if (atomic_read(&acc->retrigger_count)) {
                atomic_dec(&acc->retrigger_count);
                __knav_acc_notify(range, acc);
                writel_relaxed(1, pdsp->intd + ACC_INTD_OFFSET_COUNT(channel));
                /* ack the interrupt */
                writel_relaxed(ACC_CHANNEL_INT_BASE + channel,
                               pdsp->intd + ACC_INTD_OFFSET_EOI);

                return IRQ_HANDLED;
        }

        notifies = readl_relaxed(pdsp->intd + ACC_INTD_OFFSET_COUNT(channel));
        WARN_ON(!notifies);
        dma_sync_single_for_cpu(kdev->dev, list_dma, info->list_size,
                                DMA_FROM_DEVICE);

        for (list = list_cpu; list < list_cpu + (info->list_size / sizeof(u32));
             list += ACC_LIST_ENTRY_WORDS) {
                if (ACC_LIST_ENTRY_WORDS == 1) {
                        dev_dbg(kdev->dev,
                                "acc-irq: list %d, entry @%p, %08x\n",
                                acc->list_index, list, list[0]);
                } else if (ACC_LIST_ENTRY_WORDS == 2) {
                        dev_dbg(kdev->dev,
                                "acc-irq: list %d, entry @%p, %08x %08x\n",
                                acc->list_index, list, list[0], list[1]);
                } else if (ACC_LIST_ENTRY_WORDS == 4) {
                        dev_dbg(kdev->dev,
                                "acc-irq: list %d, entry @%p, %08x %08x %08x %08x\n",
                                acc->list_index, list, list[0], list[1],
                                list[2], list[3]);
                }

                val = list[ACC_LIST_ENTRY_DESC_IDX];
                if (!val)
                        break;

                if (range->flags & RANGE_MULTI_QUEUE) {
                        queue = list[ACC_LIST_ENTRY_QUEUE_IDX] >> 16;
                        if (queue < range_base ||
                            queue >= range_base + range->num_queues) {
                                dev_err(kdev->dev,
                                        "bad queue %d, expecting %d-%d\n",
                                        queue, range_base,
                                        range_base + range->num_queues);
                                break;
                        }
                        queue -= range_base;
                        kq = knav_range_offset_to_inst(kdev, range,
                                                                queue);
                }

                if (atomic_inc_return(&kq->desc_count) >= ACC_DESCS_MAX) {
                        atomic_dec(&kq->desc_count);
                        dev_err(kdev->dev,
                                "acc-irq: queue %d full, entry dropped\n",
                                queue + range_base);
                        continue;
                }

                idx = atomic_inc_return(&kq->desc_tail) & ACC_DESCS_MASK;
                kq->descs[idx] = val;
                kq->notify_needed = 1;
                dev_dbg(kdev->dev, "acc-irq: enqueue %08x at %d, queue %d\n",
                        val, idx, queue + range_base);
        }

        __knav_acc_notify(range, acc);
        memset(list_cpu, 0, info->list_size);
        dma_sync_single_for_device(kdev->dev, list_dma, info->list_size,
                                   DMA_TO_DEVICE);

        /* flip to the other list */
        acc->list_index ^= 1;

        /* reset the interrupt counter */
        writel_relaxed(1, pdsp->intd + ACC_INTD_OFFSET_COUNT(channel));

        /* ack the interrupt */
        writel_relaxed(ACC_CHANNEL_INT_BASE + channel,
                       pdsp->intd + ACC_INTD_OFFSET_EOI);

        return IRQ_HANDLED;
}

static int knav_range_setup_acc_irq(struct knav_range_info *range,
                                int queue, bool enabled)
{
        struct knav_device *kdev = range->kdev;
        struct knav_acc_channel *acc;
        struct cpumask *cpu_mask;
        int ret = 0, irq;
        u32 old, new;

        if (range->flags & RANGE_MULTI_QUEUE) {
                acc = range->acc;
                irq = range->irqs[0].irq;
                cpu_mask = range->irqs[0].cpu_mask;
        } else {
                acc = range->acc + queue;
                irq = range->irqs[queue].irq;
                cpu_mask = range->irqs[queue].cpu_mask;
        }

        old = acc->open_mask;
        if (enabled)
                new = old | BIT(queue);
        else
                new = old & ~BIT(queue);
        acc->open_mask = new;

        dev_dbg(kdev->dev,
                "setup-acc-irq: open mask old %08x, new %08x, channel %s\n",
                old, new, acc->name);

        if (likely(new == old))
                return 0;

        if (new && !old) {
                dev_dbg(kdev->dev,
                        "setup-acc-irq: requesting %s for channel %s\n",
                        acc->name, acc->name);
                ret = request_irq(irq, knav_acc_int_handler, 0, acc->name,
                                  range);
                if (!ret && cpu_mask) {
                        ret = irq_set_affinity_hint(irq, cpu_mask);
                        if (ret) {
                                dev_warn(range->kdev->dev,
                                         "Failed to set IRQ affinity\n");
                                return ret;
                        }
                }
        }

        if (old && !new) {
                dev_dbg(kdev->dev, "setup-acc-irq: freeing %s for channel %s\n",
                        acc->name, acc->name);
                ret = irq_set_affinity_hint(irq, NULL);
                if (ret)
                        dev_warn(range->kdev->dev,
                                 "Failed to set IRQ affinity\n");
                free_irq(irq, range);
        }

        return ret;
}

static const char *knav_acc_result_str(enum knav_acc_result result)
{
        static const char * const result_str[] = {
                [ACC_RET_IDLE]                  = "idle",
                [ACC_RET_SUCCESS]               = "success",
                [ACC_RET_INVALID_COMMAND]       = "invalid command",
                [ACC_RET_INVALID_CHANNEL]       = "invalid channel",
                [ACC_RET_INACTIVE_CHANNEL]      = "inactive channel",
                [ACC_RET_ACTIVE_CHANNEL]        = "active channel",
                [ACC_RET_INVALID_QUEUE]         = "invalid queue",
                [ACC_RET_INVALID_RET]           = "invalid return code",
        };

        if (result >= ARRAY_SIZE(result_str))
                return result_str[ACC_RET_INVALID_RET];
        else
                return result_str[result];
}

static enum knav_acc_result
knav_acc_write(struct knav_device *kdev, struct knav_pdsp_info *pdsp,
                struct knav_reg_acc_command *cmd)
{
        u32 result;

        dev_dbg(kdev->dev, "acc command %08x %08x %08x %08x %08x\n",
                cmd->command, cmd->queue_mask, cmd->list_dma,
                cmd->queue_num, cmd->timer_config);

        writel_relaxed(cmd->timer_config, &pdsp->acc_command->timer_config);
        writel_relaxed(cmd->queue_num, &pdsp->acc_command->queue_num);
        writel_relaxed(cmd->list_dma, &pdsp->acc_command->list_dma);
        writel_relaxed(cmd->queue_mask, &pdsp->acc_command->queue_mask);
        writel_relaxed(cmd->command, &pdsp->acc_command->command);

        /* wait for the command to clear */
        do {
                result = readl_relaxed(&pdsp->acc_command->command);
        } while ((result >> 8) & 0xff);

        return (result >> 24) & 0xff;
}

static void knav_acc_setup_cmd(struct knav_device *kdev,
                                struct knav_range_info *range,
                                struct knav_reg_acc_command *cmd,
                                int queue)
{
        struct knav_acc_info *info = &range->acc_info;
        struct knav_acc_channel *acc;
        int queue_base;
        u32 queue_mask;

        if (range->flags & RANGE_MULTI_QUEUE) {
                acc = range->acc;
                queue_base = range->queue_base;
                queue_mask = BIT(range->num_queues) - 1;
        } else {
                acc = range->acc + queue;
                queue_base = range->queue_base + queue;
                queue_mask = 0;
        }

        memset(cmd, 0, sizeof(*cmd));
        cmd->command    = acc->channel;
        cmd->queue_mask = queue_mask;
        cmd->list_dma   = (u32)acc->list_dma[0];
        cmd->queue_num  = info->list_entries << 16;
        cmd->queue_num |= queue_base;

        cmd->timer_config = ACC_LIST_ENTRY_TYPE << 18;
        if (range->flags & RANGE_MULTI_QUEUE)
                cmd->timer_config |= ACC_CFG_MULTI_QUEUE;
        cmd->timer_config |= info->pacing_mode << 16;
        cmd->timer_config |= info->timer_count;
}

static void knav_acc_stop(struct knav_device *kdev,
                                struct knav_range_info *range,
                                int queue)
{
        struct knav_reg_acc_command cmd;
        struct knav_acc_channel *acc;
        enum knav_acc_result result;

        acc = range->acc + queue;

        knav_acc_setup_cmd(kdev, range, &cmd, queue);
        cmd.command |= ACC_CMD_DISABLE_CHANNEL << 8;
        result = knav_acc_write(kdev, range->acc_info.pdsp, &cmd);

        dev_dbg(kdev->dev, "stopped acc channel %s, result %s\n",
                acc->name, knav_acc_result_str(result));
}

static enum knav_acc_result knav_acc_start(struct knav_device *kdev,
                                                struct knav_range_info *range,
                                                int queue)
{
        struct knav_reg_acc_command cmd;
        struct knav_acc_channel *acc;
        enum knav_acc_result result;

        acc = range->acc + queue;

        knav_acc_setup_cmd(kdev, range, &cmd, queue);
        cmd.command |= ACC_CMD_ENABLE_CHANNEL << 8;
        result = knav_acc_write(kdev, range->acc_info.pdsp, &cmd);

        dev_dbg(kdev->dev, "started acc channel %s, result %s\n",
                acc->name, knav_acc_result_str(result));

        return result;
}

static int knav_acc_init_range(struct knav_range_info *range)
{
        struct knav_device *kdev = range->kdev;
        struct knav_acc_channel *acc;
        enum knav_acc_result result;
        int queue;

        for (queue = 0; queue < range->num_queues; queue++) {
                acc = range->acc + queue;

                knav_acc_stop(kdev, range, queue);
                acc->list_index = 0;
                result = knav_acc_start(kdev, range, queue);

                if (result != ACC_RET_SUCCESS)
                        return -EIO;

                if (range->flags & RANGE_MULTI_QUEUE)
                        return 0;
        }
        return 0;
}

static int knav_acc_init_queue(struct knav_range_info *range,
                                struct knav_queue_inst *kq)
{
        unsigned id = kq->id - range->queue_base;

        kq->descs = devm_kcalloc(range->kdev->dev,
                                 ACC_DESCS_MAX, sizeof(u32), GFP_KERNEL);
        if (!kq->descs)
                return -ENOMEM;

        kq->acc = range->acc;
        if ((range->flags & RANGE_MULTI_QUEUE) == 0)
                kq->acc += id;
        return 0;
}

static int knav_acc_open_queue(struct knav_range_info *range,
                                struct knav_queue_inst *inst, unsigned flags)
{
        unsigned id = inst->id - range->queue_base;

        return knav_range_setup_acc_irq(range, id, true);
}

static int knav_acc_close_queue(struct knav_range_info *range,
                                        struct knav_queue_inst *inst)
{
        unsigned id = inst->id - range->queue_base;

        return knav_range_setup_acc_irq(range, id, false);
}

static int knav_acc_free_range(struct knav_range_info *range)
{
        struct knav_device *kdev = range->kdev;
        struct knav_acc_channel *acc;
        struct knav_acc_info *info;
        int channel, channels;

        info = &range->acc_info;

        if (range->flags & RANGE_MULTI_QUEUE)
                channels = 1;
        else
                channels = range->num_queues;

        for (channel = 0; channel < channels; channel++) {
                acc = range->acc + channel;
                if (!acc->list_cpu[0])
                        continue;
                dma_unmap_single(kdev->dev, acc->list_dma[0],
                                 info->mem_size, DMA_BIDIRECTIONAL);
                free_pages_exact(acc->list_cpu[0], info->mem_size);
        }
        devm_kfree(range->kdev->dev, range->acc);
        return 0;
}

static const struct knav_range_ops knav_acc_range_ops = {
        .set_notify     = knav_acc_set_notify,
        .init_queue     = knav_acc_init_queue,
        .open_queue     = knav_acc_open_queue,
        .close_queue    = knav_acc_close_queue,
        .init_range     = knav_acc_init_range,
        .free_range     = knav_acc_free_range,
};

/**
 * knav_init_acc_range: Initialise accumulator ranges
 *
 * @kdev:               qmss device
 * @node:               device node
 * @range:              qmms range information
 *
 * Return 0 on success or error
 */
int knav_init_acc_range(struct knav_device *kdev,
                        struct device_node *node,
                        struct knav_range_info *range)
{
        struct knav_acc_channel *acc;
        struct knav_pdsp_info *pdsp;
        struct knav_acc_info *info;
        int ret, channel, channels;
        int list_size, mem_size;
        dma_addr_t list_dma;
        void *list_mem;
        u32 config[5];

        range->flags |= RANGE_HAS_ACCUMULATOR;
        info = &range->acc_info;

        ret = of_property_read_u32_array(node, "accumulator", config, 5);
        if (ret)
                return ret;

        info->pdsp_id           = config[0];
        info->start_channel     = config[1];
        info->list_entries      = config[2];
        info->pacing_mode       = config[3];
        info->timer_count       = config[4] / ACC_DEFAULT_PERIOD;

        if (info->start_channel > ACC_MAX_CHANNEL) {
                dev_err(kdev->dev, "channel %d invalid for range %s\n",
                        info->start_channel, range->name);
                return -EINVAL;
        }

        if (info->pacing_mode > 3) {
                dev_err(kdev->dev, "pacing mode %d invalid for range %s\n",
                        info->pacing_mode, range->name);
                return -EINVAL;
        }

        pdsp = knav_find_pdsp(kdev, info->pdsp_id);
        if (!pdsp) {
                dev_err(kdev->dev, "pdsp id %d not found for range %s\n",
                        info->pdsp_id, range->name);
                return -EINVAL;
        }

        if (!pdsp->started) {
                dev_err(kdev->dev, "pdsp id %d not started for range %s\n",
                        info->pdsp_id, range->name);
                return -ENODEV;
        }

        info->pdsp = pdsp;
        channels = range->num_queues;
        if (of_property_read_bool(node, "multi-queue")) {
                range->flags |= RANGE_MULTI_QUEUE;
                channels = 1;
                if (range->queue_base & (32 - 1)) {
                        dev_err(kdev->dev,
                                "misaligned multi-queue accumulator range %s\n",
                                range->name);
                        return -EINVAL;
                }
                if (range->num_queues > 32) {
                        dev_err(kdev->dev,
                                "too many queues in accumulator range %s\n",
                                range->name);
                        return -EINVAL;
                }
        }

        /* figure out list size */
        list_size  = info->list_entries;
        list_size *= ACC_LIST_ENTRY_WORDS * sizeof(u32);
        info->list_size = list_size;
        mem_size   = PAGE_ALIGN(list_size * 2);
        info->mem_size  = mem_size;
        range->acc = devm_kcalloc(kdev->dev, channels, sizeof(*range->acc),
                                  GFP_KERNEL);
        if (!range->acc)
                return -ENOMEM;

        for (channel = 0; channel < channels; channel++) {
                acc = range->acc + channel;
                acc->channel = info->start_channel + channel;

                /* allocate memory for the two lists */
                list_mem = alloc_pages_exact(mem_size, GFP_KERNEL | GFP_DMA);
                if (!list_mem)
                        return -ENOMEM;

                list_dma = dma_map_single(kdev->dev, list_mem, mem_size,
                                          DMA_BIDIRECTIONAL);
                if (dma_mapping_error(kdev->dev, list_dma)) {
                        free_pages_exact(list_mem, mem_size);
                        return -ENOMEM;
                }

                memset(list_mem, 0, mem_size);
                dma_sync_single_for_device(kdev->dev, list_dma, mem_size,
                                           DMA_TO_DEVICE);
                scnprintf(acc->name, sizeof(acc->name), "hwqueue-acc-%d",
                          acc->channel);
                acc->list_cpu[0] = list_mem;
                acc->list_cpu[1] = list_mem + list_size;
                acc->list_dma[0] = list_dma;
                acc->list_dma[1] = list_dma + list_size;
                dev_dbg(kdev->dev, "%s: channel %d, dma %pad, virt %8p\n",
                        acc->name, acc->channel, &list_dma, list_mem);
        }

        range->ops = &knav_acc_range_ops;
        return 0;
}
EXPORT_SYMBOL_GPL(knav_init_acc_range);