root/drivers/net/ipa/ipa_resource.c
// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
 * Copyright (C) 2018-2024 Linaro Ltd.
 */

#include <linux/types.h>

#include "ipa.h"
#include "ipa_data.h"
#include "ipa_reg.h"
#include "ipa_resource.h"

/**
 * DOC: IPA Resources
 *
 * The IPA manages a set of resources internally for various purposes.
 * A given IPA version has a fixed number of resource types, and a fixed
 * total number of resources of each type.  "Source" resource types
 * are separate from "destination" resource types.
 *
 * Each version of IPA also has some number of resource groups.  Each
 * endpoint is assigned to a resource group, and all endpoints in the
 * same group share pools of each type of resource.  A subset of the
 * total resources of each type is assigned for use by each group.
 */

static bool ipa_resource_limits_valid(struct ipa *ipa,
                                      const struct ipa_resource_data *data)
{
        u32 group_count;
        u32 i;
        u32 j;

        /* We program at most 8 source or destination resource group limits */
        BUILD_BUG_ON(IPA_RESOURCE_GROUP_MAX > 8);

        group_count = data->rsrc_group_src_count;
        if (!group_count || group_count > IPA_RESOURCE_GROUP_MAX)
                return false;

        /* Return an error if a non-zero resource limit is specified
         * for a resource group not supported by hardware.
         */
        for (i = 0; i < data->resource_src_count; i++) {
                const struct ipa_resource *resource;

                resource = &data->resource_src[i];
                for (j = group_count; j < IPA_RESOURCE_GROUP_MAX; j++)
                        if (resource->limits[j].min || resource->limits[j].max)
                                return false;
        }

        group_count = data->rsrc_group_dst_count;
        if (!group_count || group_count > IPA_RESOURCE_GROUP_MAX)
                return false;

        for (i = 0; i < data->resource_dst_count; i++) {
                const struct ipa_resource *resource;

                resource = &data->resource_dst[i];
                for (j = group_count; j < IPA_RESOURCE_GROUP_MAX; j++)
                        if (resource->limits[j].min || resource->limits[j].max)
                                return false;
        }

        return true;
}

static void
ipa_resource_config_common(struct ipa *ipa, u32 resource_type,
                           const struct reg *reg,
                           const struct ipa_resource_limits *xlimits,
                           const struct ipa_resource_limits *ylimits)
{
        u32 val;

        val = reg_encode(reg, X_MIN_LIM, xlimits->min);
        val |= reg_encode(reg, X_MAX_LIM, xlimits->max);
        if (ylimits) {
                val |= reg_encode(reg, Y_MIN_LIM, ylimits->min);
                val |= reg_encode(reg, Y_MAX_LIM, ylimits->max);
        }

        iowrite32(val, ipa->reg_virt + reg_n_offset(reg, resource_type));
}

static void ipa_resource_config_src(struct ipa *ipa, u32 resource_type,
                                    const struct ipa_resource_data *data)
{
        u32 group_count = data->rsrc_group_src_count;
        const struct ipa_resource_limits *ylimits;
        const struct ipa_resource *resource;
        const struct reg *reg;

        resource = &data->resource_src[resource_type];

        reg = ipa_reg(ipa, SRC_RSRC_GRP_01_RSRC_TYPE);
        ylimits = group_count == 1 ? NULL : &resource->limits[1];
        ipa_resource_config_common(ipa, resource_type, reg,
                                   &resource->limits[0], ylimits);
        if (group_count < 3)
                return;

        reg = ipa_reg(ipa, SRC_RSRC_GRP_23_RSRC_TYPE);
        ylimits = group_count == 3 ? NULL : &resource->limits[3];
        ipa_resource_config_common(ipa, resource_type, reg,
                                   &resource->limits[2], ylimits);
        if (group_count < 5)
                return;

        reg = ipa_reg(ipa, SRC_RSRC_GRP_45_RSRC_TYPE);
        ylimits = group_count == 5 ? NULL : &resource->limits[5];
        ipa_resource_config_common(ipa, resource_type, reg,
                                   &resource->limits[4], ylimits);
        if (group_count < 7)
                return;

        reg = ipa_reg(ipa, SRC_RSRC_GRP_67_RSRC_TYPE);
        ylimits = group_count == 7 ? NULL : &resource->limits[7];
        ipa_resource_config_common(ipa, resource_type, reg,
                                   &resource->limits[6], ylimits);
}

static void ipa_resource_config_dst(struct ipa *ipa, u32 resource_type,
                                    const struct ipa_resource_data *data)
{
        u32 group_count = data->rsrc_group_dst_count;
        const struct ipa_resource_limits *ylimits;
        const struct ipa_resource *resource;
        const struct reg *reg;

        resource = &data->resource_dst[resource_type];

        reg = ipa_reg(ipa, DST_RSRC_GRP_01_RSRC_TYPE);
        ylimits = group_count == 1 ? NULL : &resource->limits[1];
        ipa_resource_config_common(ipa, resource_type, reg,
                                   &resource->limits[0], ylimits);
        if (group_count < 3)
                return;

        reg = ipa_reg(ipa, DST_RSRC_GRP_23_RSRC_TYPE);
        ylimits = group_count == 3 ? NULL : &resource->limits[3];
        ipa_resource_config_common(ipa, resource_type, reg,
                                   &resource->limits[2], ylimits);
        if (group_count < 5)
                return;

        reg = ipa_reg(ipa, DST_RSRC_GRP_45_RSRC_TYPE);
        ylimits = group_count == 5 ? NULL : &resource->limits[5];
        ipa_resource_config_common(ipa, resource_type, reg,
                                   &resource->limits[4], ylimits);
        if (group_count < 7)
                return;

        reg = ipa_reg(ipa, DST_RSRC_GRP_67_RSRC_TYPE);
        ylimits = group_count == 7 ? NULL : &resource->limits[7];
        ipa_resource_config_common(ipa, resource_type, reg,
                                   &resource->limits[6], ylimits);
}

/* Configure resources; there is no ipa_resource_deconfig() */
int ipa_resource_config(struct ipa *ipa, const struct ipa_resource_data *data)
{
        u32 i;

        if (!ipa_resource_limits_valid(ipa, data))
                return -EINVAL;

        for (i = 0; i < data->resource_src_count; i++)
                ipa_resource_config_src(ipa, i, data);

        for (i = 0; i < data->resource_dst_count; i++)
                ipa_resource_config_dst(ipa, i, data);

        return 0;
}