root/drivers/mmc/host/mmci_qcom_dml.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 *
 * Copyright (c) 2011, The Linux Foundation. All rights reserved.
 */
#include <linux/of.h>
#include <linux/of_dma.h>
#include <linux/bitops.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include "mmci.h"

/* Registers */
#define DML_CONFIG                      0x00
#define PRODUCER_CRCI_MSK               GENMASK(1, 0)
#define PRODUCER_CRCI_DISABLE           0
#define PRODUCER_CRCI_X_SEL             BIT(0)
#define PRODUCER_CRCI_Y_SEL             BIT(1)
#define CONSUMER_CRCI_MSK               GENMASK(3, 2)
#define CONSUMER_CRCI_DISABLE           0
#define CONSUMER_CRCI_X_SEL             BIT(2)
#define CONSUMER_CRCI_Y_SEL             BIT(3)
#define PRODUCER_TRANS_END_EN           BIT(4)
#define BYPASS                          BIT(16)
#define DIRECT_MODE                     BIT(17)
#define INFINITE_CONS_TRANS             BIT(18)

#define DML_SW_RESET                    0x08
#define DML_PRODUCER_START              0x0c
#define DML_CONSUMER_START              0x10
#define DML_PRODUCER_PIPE_LOGICAL_SIZE  0x14
#define DML_CONSUMER_PIPE_LOGICAL_SIZE  0x18
#define DML_PIPE_ID                     0x1c
#define PRODUCER_PIPE_ID_SHFT           0
#define PRODUCER_PIPE_ID_MSK            GENMASK(4, 0)
#define CONSUMER_PIPE_ID_SHFT           16
#define CONSUMER_PIPE_ID_MSK            GENMASK(20, 16)

#define DML_PRODUCER_BAM_BLOCK_SIZE     0x24
#define DML_PRODUCER_BAM_TRANS_SIZE     0x28

/* other definitions */
#define PRODUCER_PIPE_LOGICAL_SIZE      4096
#define CONSUMER_PIPE_LOGICAL_SIZE      4096

#define DML_OFFSET                      0x800

static int qcom_dma_start(struct mmci_host *host, unsigned int *datactrl)
{
        u32 config;
        void __iomem *base = host->base + DML_OFFSET;
        struct mmc_data *data = host->data;
        int ret = mmci_dmae_start(host, datactrl);

        if (ret)
                return ret;

        if (data->flags & MMC_DATA_READ) {
                /* Read operation: configure DML for producer operation */
                /* Set producer CRCI-x and disable consumer CRCI */
                config = readl_relaxed(base + DML_CONFIG);
                config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
                config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
                writel_relaxed(config, base + DML_CONFIG);

                /* Set the Producer BAM block size */
                writel_relaxed(data->blksz, base + DML_PRODUCER_BAM_BLOCK_SIZE);

                /* Set Producer BAM Transaction size */
                writel_relaxed(data->blocks * data->blksz,
                               base + DML_PRODUCER_BAM_TRANS_SIZE);
                /* Set Producer Transaction End bit */
                config = readl_relaxed(base + DML_CONFIG);
                config |= PRODUCER_TRANS_END_EN;
                writel_relaxed(config, base + DML_CONFIG);
                /* Trigger producer */
                writel_relaxed(1, base + DML_PRODUCER_START);
        } else {
                /* Write operation: configure DML for consumer operation */
                /* Set consumer CRCI-x and disable producer CRCI*/
                config = readl_relaxed(base + DML_CONFIG);
                config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
                config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
                writel_relaxed(config, base + DML_CONFIG);
                /* Clear Producer Transaction End bit */
                config = readl_relaxed(base + DML_CONFIG);
                config &= ~PRODUCER_TRANS_END_EN;
                writel_relaxed(config, base + DML_CONFIG);
                /* Trigger consumer */
                writel_relaxed(1, base + DML_CONSUMER_START);
        }

        /* make sure the dml is configured before dma is triggered */
        wmb();
        return 0;
}

static int of_get_dml_pipe_index(struct device_node *np, const char *name)
{
        int index;
        struct of_phandle_args  dma_spec;

        index = of_property_match_string(np, "dma-names", name);

        if (index < 0)
                return -ENODEV;

        if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
                                       &dma_spec))
                return -ENODEV;

        of_node_put(dma_spec.np);
        if (dma_spec.args_count)
                return dma_spec.args[0];

        return -ENODEV;
}

/* Initialize the dml hardware connected to SD Card controller */
static int qcom_dma_setup(struct mmci_host *host)
{
        u32 config;
        void __iomem *base;
        int consumer_id, producer_id;
        struct device_node *np = host->mmc->parent->of_node;

        if (mmci_dmae_setup(host))
                return -EINVAL;

        consumer_id = of_get_dml_pipe_index(np, "tx");
        producer_id = of_get_dml_pipe_index(np, "rx");

        if (producer_id < 0 || consumer_id < 0) {
                mmci_dmae_release(host);
                return -EINVAL;
        }

        base = host->base + DML_OFFSET;

        /* Reset the DML block */
        writel_relaxed(1, base + DML_SW_RESET);

        /* Disable the producer and consumer CRCI */
        config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
        /*
         * Disable the bypass mode. Bypass mode will only be used
         * if data transfer is to happen in PIO mode and don't
         * want the BAM interface to connect with SDCC-DML.
         */
        config &= ~BYPASS;
        /*
         * Disable direct mode as we don't DML to MASTER the AHB bus.
         * BAM connected with DML should MASTER the AHB bus.
         */
        config &= ~DIRECT_MODE;
        /*
         * Disable infinite mode transfer as we won't be doing any
         * infinite size data transfers. All data transfer will be
         * of finite data size.
         */
        config &= ~INFINITE_CONS_TRANS;
        writel_relaxed(config, base + DML_CONFIG);

        /*
         * Initialize the logical BAM pipe size for producer
         * and consumer.
         */
        writel_relaxed(PRODUCER_PIPE_LOGICAL_SIZE,
                       base + DML_PRODUCER_PIPE_LOGICAL_SIZE);
        writel_relaxed(CONSUMER_PIPE_LOGICAL_SIZE,
                       base + DML_CONSUMER_PIPE_LOGICAL_SIZE);

        /* Initialize Producer/consumer pipe id */
        writel_relaxed(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
                       base + DML_PIPE_ID);

        /* Make sure dml initialization is finished */
        mb();

        return 0;
}

static u32 qcom_get_dctrl_cfg(struct mmci_host *host)
{
        return MCI_DPSM_ENABLE | (host->data->blksz << 4);
}

static struct mmci_host_ops qcom_variant_ops = {
        .prep_data = mmci_dmae_prep_data,
        .unprep_data = mmci_dmae_unprep_data,
        .get_datactrl_cfg = qcom_get_dctrl_cfg,
        .get_next_data = mmci_dmae_get_next_data,
        .dma_setup = qcom_dma_setup,
        .dma_release = mmci_dmae_release,
        .dma_start = qcom_dma_start,
        .dma_finalize = mmci_dmae_finalize,
        .dma_error = mmci_dmae_error,
};

void qcom_variant_init(struct mmci_host *host)
{
        host->ops = &qcom_variant_ops;
}