root/drivers/net/wwan/t7xx/t7xx_pcie_mac.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2021, MediaTek Inc.
 * Copyright (c) 2021-2022, Intel Corporation.
 *
 * Authors:
 *  Haijun Liu <haijun.liu@mediatek.com>
 *  Moises Veleta <moises.veleta@intel.com>
 *  Sreehari Kancharla <sreehari.kancharla@intel.com>
 *
 * Contributors:
 *  Amir Hanania <amir.hanania@intel.com>
 *  Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
 *  Ricardo Martinez <ricardo.martinez@linux.intel.com>
 */

#include <linux/bits.h>
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/types.h>

#include "t7xx_pci.h"
#include "t7xx_pcie_mac.h"
#include "t7xx_reg.h"

#define T7XX_PCIE_REG_BAR               2
#define T7XX_PCIE_REG_PORT              ATR_SRC_PCI_WIN0
#define T7XX_PCIE_REG_TABLE_NUM         0
#define T7XX_PCIE_REG_TRSL_PORT         ATR_DST_AXIM_0

#define T7XX_PCIE_DEV_DMA_PORT_START    ATR_SRC_AXIS_0
#define T7XX_PCIE_DEV_DMA_PORT_END      ATR_SRC_AXIS_2
#define T7XX_PCIE_DEV_DMA_TABLE_NUM     0
#define T7XX_PCIE_DEV_DMA_TRSL_ADDR     0
#define T7XX_PCIE_DEV_DMA_SRC_ADDR      0
#define T7XX_PCIE_DEV_DMA_TRANSPARENT   1
#define T7XX_PCIE_DEV_DMA_SIZE          0

enum t7xx_atr_src_port {
        ATR_SRC_PCI_WIN0,
        ATR_SRC_PCI_WIN1,
        ATR_SRC_AXIS_0,
        ATR_SRC_AXIS_1,
        ATR_SRC_AXIS_2,
        ATR_SRC_AXIS_3,
};

enum t7xx_atr_dst_port {
        ATR_DST_PCI_TRX,
        ATR_DST_PCI_CONFIG,
        ATR_DST_AXIM_0 = 4,
        ATR_DST_AXIM_1,
        ATR_DST_AXIM_2,
        ATR_DST_AXIM_3,
};

struct t7xx_atr_config {
        u64                     src_addr;
        u64                     trsl_addr;
        u64                     size;
        u32                     port;
        u32                     table;
        enum t7xx_atr_dst_port  trsl_id;
        u32                     transparent;
};

static void t7xx_pcie_mac_atr_tables_dis(void __iomem *pbase, enum t7xx_atr_src_port port)
{
        void __iomem *reg;
        int i, offset;

        for (i = 0; i < ATR_TABLE_NUM_PER_ATR; i++) {
                offset = ATR_PORT_OFFSET * port + ATR_TABLE_OFFSET * i;
                reg = pbase + ATR_PCIE_WIN0_T0_ATR_PARAM_SRC_ADDR + offset;
                iowrite64_lo_hi(0, reg);
        }
}

static int t7xx_pcie_mac_atr_cfg(struct t7xx_pci_dev *t7xx_dev, struct t7xx_atr_config *cfg)
{
        struct device *dev = &t7xx_dev->pdev->dev;
        void __iomem *pbase = IREG_BASE(t7xx_dev);
        int atr_size, pos, offset;
        void __iomem *reg;
        u64 value;

        if (cfg->transparent) {
                /* No address conversion is performed */
                atr_size = ATR_TRANSPARENT_SIZE;
        } else {
                if (cfg->src_addr & (cfg->size - 1)) {
                        dev_err(dev, "Source address is not aligned to size\n");
                        return -EINVAL;
                }

                if (cfg->trsl_addr & (cfg->size - 1)) {
                        dev_err(dev, "Translation address %llx is not aligned to size %llx\n",
                                cfg->trsl_addr, cfg->size - 1);
                        return -EINVAL;
                }

                pos = __ffs64(cfg->size);

                /* HW calculates the address translation space as 2^(atr_size + 1) */
                atr_size = pos - 1;
        }

        offset = ATR_PORT_OFFSET * cfg->port + ATR_TABLE_OFFSET * cfg->table;

        reg = pbase + ATR_PCIE_WIN0_T0_TRSL_ADDR + offset;
        value = cfg->trsl_addr & ATR_PCIE_WIN0_ADDR_ALGMT;
        iowrite64_lo_hi(value, reg);

        reg = pbase + ATR_PCIE_WIN0_T0_TRSL_PARAM + offset;
        iowrite32(cfg->trsl_id, reg);

        reg = pbase + ATR_PCIE_WIN0_T0_ATR_PARAM_SRC_ADDR + offset;
        value = (cfg->src_addr & ATR_PCIE_WIN0_ADDR_ALGMT) | (atr_size << 1) | BIT(0);
        iowrite64_lo_hi(value, reg);

        /* Ensure ATR is set */
        ioread64_lo_hi(reg);
        return 0;
}

/**
 * t7xx_pcie_mac_atr_init() - Initialize address translation.
 * @t7xx_dev: MTK device.
 *
 * Setup ATR for ports & device.
 */
void t7xx_pcie_mac_atr_init(struct t7xx_pci_dev *t7xx_dev)
{
        struct t7xx_atr_config cfg;
        u32 i;

        /* Disable for all ports */
        for (i = ATR_SRC_PCI_WIN0; i <= ATR_SRC_AXIS_3; i++)
                t7xx_pcie_mac_atr_tables_dis(IREG_BASE(t7xx_dev), i);

        memset(&cfg, 0, sizeof(cfg));
        /* Config ATR for RC to access device's register */
        cfg.src_addr = pci_resource_start(t7xx_dev->pdev, T7XX_PCIE_REG_BAR);
        cfg.size = T7XX_PCIE_REG_SIZE_CHIP;
        cfg.trsl_addr = T7XX_PCIE_REG_TRSL_ADDR_CHIP;
        cfg.port = T7XX_PCIE_REG_PORT;
        cfg.table = T7XX_PCIE_REG_TABLE_NUM;
        cfg.trsl_id = T7XX_PCIE_REG_TRSL_PORT;
        t7xx_pcie_mac_atr_tables_dis(IREG_BASE(t7xx_dev), cfg.port);
        t7xx_pcie_mac_atr_cfg(t7xx_dev, &cfg);

        t7xx_dev->base_addr.pcie_dev_reg_trsl_addr = T7XX_PCIE_REG_TRSL_ADDR_CHIP;

        /* Config ATR for EP to access RC's memory */
        for (i = T7XX_PCIE_DEV_DMA_PORT_START; i <= T7XX_PCIE_DEV_DMA_PORT_END; i++) {
                cfg.src_addr = T7XX_PCIE_DEV_DMA_SRC_ADDR;
                cfg.size = T7XX_PCIE_DEV_DMA_SIZE;
                cfg.trsl_addr = T7XX_PCIE_DEV_DMA_TRSL_ADDR;
                cfg.port = i;
                cfg.table = T7XX_PCIE_DEV_DMA_TABLE_NUM;
                cfg.trsl_id = ATR_DST_PCI_TRX;
                cfg.transparent = T7XX_PCIE_DEV_DMA_TRANSPARENT;
                t7xx_pcie_mac_atr_tables_dis(IREG_BASE(t7xx_dev), cfg.port);
                t7xx_pcie_mac_atr_cfg(t7xx_dev, &cfg);
        }
}

/**
 * t7xx_pcie_mac_enable_disable_int() - Enable/disable interrupts.
 * @t7xx_dev: MTK device.
 * @enable: Enable/disable.
 *
 * Enable or disable device interrupts.
 */
static void t7xx_pcie_mac_enable_disable_int(struct t7xx_pci_dev *t7xx_dev, bool enable)
{
        u32 value;

        value = ioread32(IREG_BASE(t7xx_dev) + ISTAT_HST_CTRL);

        if (enable)
                value &= ~ISTAT_HST_CTRL_DIS;
        else
                value |= ISTAT_HST_CTRL_DIS;

        iowrite32(value, IREG_BASE(t7xx_dev) + ISTAT_HST_CTRL);
}

void t7xx_pcie_mac_interrupts_en(struct t7xx_pci_dev *t7xx_dev)
{
        t7xx_pcie_mac_enable_disable_int(t7xx_dev, true);
}

void t7xx_pcie_mac_interrupts_dis(struct t7xx_pci_dev *t7xx_dev)
{
        t7xx_pcie_mac_enable_disable_int(t7xx_dev, false);
}

/**
 * t7xx_pcie_mac_clear_set_int() - Clear/set interrupt by type.
 * @t7xx_dev: MTK device.
 * @int_type: Interrupt type.
 * @clear: Clear/set.
 *
 * Clear or set device interrupt by type.
 */
static void t7xx_pcie_mac_clear_set_int(struct t7xx_pci_dev *t7xx_dev,
                                        enum t7xx_int int_type, bool clear)
{
        void __iomem *reg;
        u32 val;

        if (clear)
                reg = IREG_BASE(t7xx_dev) + IMASK_HOST_MSIX_CLR_GRP0_0;
        else
                reg = IREG_BASE(t7xx_dev) + IMASK_HOST_MSIX_SET_GRP0_0;

        val = BIT(EXT_INT_START + int_type);
        iowrite32(val, reg);
}

void t7xx_pcie_mac_clear_int(struct t7xx_pci_dev *t7xx_dev, enum t7xx_int int_type)
{
        t7xx_pcie_mac_clear_set_int(t7xx_dev, int_type, true);
}

void t7xx_pcie_mac_set_int(struct t7xx_pci_dev *t7xx_dev, enum t7xx_int int_type)
{
        t7xx_pcie_mac_clear_set_int(t7xx_dev, int_type, false);
}

/**
 * t7xx_pcie_mac_clear_int_status() - Clear interrupt status by type.
 * @t7xx_dev: MTK device.
 * @int_type: Interrupt type.
 *
 * Enable or disable device interrupts' status by type.
 */
void t7xx_pcie_mac_clear_int_status(struct t7xx_pci_dev *t7xx_dev, enum t7xx_int int_type)
{
        void __iomem *reg = IREG_BASE(t7xx_dev) + MSIX_ISTAT_HST_GRP0_0;
        u32 val = BIT(EXT_INT_START + int_type);

        iowrite32(val, reg);
}

/**
 * t7xx_pcie_set_mac_msix_cfg() - Write MSIX control configuration.
 * @t7xx_dev: MTK device.
 * @irq_count: Number of MSIX IRQ vectors.
 *
 * Write IRQ count to device.
 */
void t7xx_pcie_set_mac_msix_cfg(struct t7xx_pci_dev *t7xx_dev, unsigned int irq_count)
{
        u32 val = ffs(irq_count) * 2 - 1;

        iowrite32(val, IREG_BASE(t7xx_dev) + T7XX_PCIE_CFG_MSIX);
}