// SPDX-License-Identifier: GPL-2.0

/* Copyright (C) 2023-2024 Linaro Ltd. */

#include <linux/io.h>
#include <linux/platform_device.h>

#include "gsi.h"
#include "gsi_reg.h"
#include "reg.h"

/* Is this register ID valid for the current GSI version? */
static bool gsi_reg_id_valid(struct gsi *gsi, enum gsi_reg_id reg_id)
{
        switch (reg_id) {
        case INTER_EE_SRC_CH_IRQ_MSK:
        case INTER_EE_SRC_EV_CH_IRQ_MSK:
                return gsi->version >= IPA_VERSION_3_5;

        case HW_PARAM_2:
                return gsi->version >= IPA_VERSION_3_5_1;

        case HW_PARAM_4:
                return gsi->version >= IPA_VERSION_5_0;

        case CH_C_CNTXT_0:
        case CH_C_CNTXT_1:
        case CH_C_CNTXT_2:
        case CH_C_CNTXT_3:
        case CH_C_QOS:
        case CH_C_SCRATCH_0:
        case CH_C_SCRATCH_1:
        case CH_C_SCRATCH_2:
        case CH_C_SCRATCH_3:
        case EV_CH_E_CNTXT_0:
        case EV_CH_E_CNTXT_1:
        case EV_CH_E_CNTXT_2:
        case EV_CH_E_CNTXT_3:
        case EV_CH_E_CNTXT_4:
        case EV_CH_E_CNTXT_8:
        case EV_CH_E_CNTXT_9:
        case EV_CH_E_CNTXT_10:
        case EV_CH_E_CNTXT_11:
        case EV_CH_E_CNTXT_12:
        case EV_CH_E_CNTXT_13:
        case EV_CH_E_SCRATCH_0:
        case EV_CH_E_SCRATCH_1:
        case CH_C_DOORBELL_0:
        case EV_CH_E_DOORBELL_0:
        case GSI_STATUS:
        case CH_CMD:
        case EV_CH_CMD:
        case GENERIC_CMD:
        case CNTXT_TYPE_IRQ:
        case CNTXT_TYPE_IRQ_MSK:
        case CNTXT_SRC_CH_IRQ:
        case CNTXT_SRC_CH_IRQ_MSK:
        case CNTXT_SRC_CH_IRQ_CLR:
        case CNTXT_SRC_EV_CH_IRQ:
        case CNTXT_SRC_EV_CH_IRQ_MSK:
        case CNTXT_SRC_EV_CH_IRQ_CLR:
        case CNTXT_SRC_IEOB_IRQ:
        case CNTXT_SRC_IEOB_IRQ_MSK:
        case CNTXT_SRC_IEOB_IRQ_CLR:
        case CNTXT_GLOB_IRQ_STTS:
        case CNTXT_GLOB_IRQ_EN:
        case CNTXT_GLOB_IRQ_CLR:
        case CNTXT_GSI_IRQ_STTS:
        case CNTXT_GSI_IRQ_EN:
        case CNTXT_GSI_IRQ_CLR:
        case CNTXT_INTSET:
        case ERROR_LOG:
        case ERROR_LOG_CLR:
        case CNTXT_SCRATCH_0:
                return true;

        default:
                return false;
        }
}

const struct reg *gsi_reg(struct gsi *gsi, enum gsi_reg_id reg_id)
{
        if (WARN(!gsi_reg_id_valid(gsi, reg_id), "invalid reg %u\n", reg_id))
                return NULL;

        return reg(gsi->regs, reg_id);
}

static const struct regs *gsi_regs(struct gsi *gsi)
{
        switch (gsi->version) {
        case IPA_VERSION_3_1:
                return &gsi_regs_v3_1;

        case IPA_VERSION_3_5_1:
                return &gsi_regs_v3_5_1;

        case IPA_VERSION_4_2:
                return &gsi_regs_v4_0;

        case IPA_VERSION_4_5:
        case IPA_VERSION_4_7:
                return &gsi_regs_v4_5;

        case IPA_VERSION_4_9:
                return &gsi_regs_v4_9;

        case IPA_VERSION_4_11:
                return &gsi_regs_v4_11;

        case IPA_VERSION_5_0:
        case IPA_VERSION_5_5:
                return &gsi_regs_v5_0;

        default:
                return NULL;
        }
}

/* Sets gsi->virt and I/O maps the "gsi" memory range for registers */
int gsi_reg_init(struct gsi *gsi, struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct resource *res;
        resource_size_t size;

        /* Get GSI memory range and map it */
        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "gsi");
        if (!res) {
                dev_err(dev, "DT error getting \"gsi\" memory property\n");
                return -ENODEV;
        }

        size = resource_size(res);
        if (res->start > U32_MAX || size > U32_MAX - res->start) {
                dev_err(dev, "DT memory resource \"gsi\" out of range\n");
                return -EINVAL;
        }

        gsi->regs = gsi_regs(gsi);
        if (!gsi->regs) {
                dev_err(dev, "unsupported IPA version %u (?)\n", gsi->version);
                return -EINVAL;
        }

        gsi->virt = ioremap(res->start, size);
        if (!gsi->virt) {
                dev_err(dev, "unable to remap \"gsi\" memory\n");
                return -ENOMEM;
        }

        return 0;
}

/* Inverse of gsi_reg_init() */
void gsi_reg_exit(struct gsi *gsi)
{
        iounmap(gsi->virt);
        gsi->virt = NULL;
        gsi->regs = NULL;
}