Re: [PATCH 2/2] mmc: sdhci-of-ma35d1: Add Novoton MA35D1 SDHCI driver

[Shan-Chun Hung <shanchun1218@gmail.com>]

Dear Dragan,

Thanks for your review.  I didn't notice the typo , but I will correct it.

Best Regards,
Shan-Chun.

On 2024/6/19 下午 06:18, Dragan Simic wrote:
> Hello Shan-Chun,
>
> On 2024-06-19 07:46, Shan-Chun Hung wrote:
>> This adds the SDHCI driver for the MA35 series SoC. It is based upon the
>> SDHCI interface, but requires some extra initialization.
>>
>> Signed-off-by: schung <schung@nuvoton.com>
>
> There's a typo in the patch subject: s/Novoton/Nuvoton/
>
> Also, it would be better to use imperative mode in the patch description,
> i.e. "Add the SDHCI driver..." instead of "This adds the SDHCI..."
>
>> ---
>>  drivers/mmc/host/Kconfig           |  13 ++
>>  drivers/mmc/host/Makefile          |   1 +
>>  drivers/mmc/host/sdhci-of-ma35d1.c | 297 +++++++++++++++++++++++++++++
>>  3 files changed, 311 insertions(+)
>>  create mode 100644 drivers/mmc/host/sdhci-of-ma35d1.c
>>
>> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
>> index bb0d4fb0892a..e993901ebedd 100644
>> --- a/drivers/mmc/host/Kconfig
>> +++ b/drivers/mmc/host/Kconfig
>> @@ -252,6 +252,19 @@ config MMC_SDHCI_OF_SPARX5
>>
>>       If unsure, say N.
>>
>> +config MMC_SDHCI_OF_MA35D1
>> +    tristate "SDHCI OF support for the MA35D1 SDHCI controller"
>> +    depends on ARCH_A35 || COMPILE_TEST
>> +    depends on MMC_SDHCI_PLTFM
>> +    depends on OF && COMMON_CLK
>> +    help
>> +      This selects the MA35D1 Secure Digital Host Controller Interface.
>> +
>> +      If you have a controller with this interface, say Y or M here. 
>> You
>> +      also need to enable an appropriate bus interface.
>> +
>> +      If unsure, say N.
>> +
>>  config MMC_SDHCI_CADENCE
>>     tristate "SDHCI support for the Cadence SD/SDIO/eMMC controller"
>>     depends on MMC_SDHCI_PLTFM
>> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
>> index f53f86d200ac..3ccffebbe59b 100644
>> --- a/drivers/mmc/host/Makefile
>> +++ b/drivers/mmc/host/Makefile
>> @@ -88,6 +88,7 @@ obj-$(CONFIG_MMC_SDHCI_OF_ESDHC)    += 
>> sdhci-of-esdhc.o
>>  obj-$(CONFIG_MMC_SDHCI_OF_HLWD)        += sdhci-of-hlwd.o
>>  obj-$(CONFIG_MMC_SDHCI_OF_DWCMSHC)    += sdhci-of-dwcmshc.o
>>  obj-$(CONFIG_MMC_SDHCI_OF_SPARX5)    += sdhci-of-sparx5.o
>> +obj-$(CONFIG_MMC_SDHCI_OF_MA35D1)    += sdhci-of-ma35d1.o
>>  obj-$(CONFIG_MMC_SDHCI_BCM_KONA)    += sdhci-bcm-kona.o
>>  obj-$(CONFIG_MMC_SDHCI_IPROC)        += sdhci-iproc.o
>>  obj-$(CONFIG_MMC_SDHCI_NPCM)        += sdhci-npcm.o
>> diff --git a/drivers/mmc/host/sdhci-of-ma35d1.c
>> b/drivers/mmc/host/sdhci-of-ma35d1.c
>> new file mode 100644
>> index 000000000000..7714a5ab463d
>> --- /dev/null
>> +++ b/drivers/mmc/host/sdhci-of-ma35d1.c
>> @@ -0,0 +1,297 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2024 Nuvoton Technology Corp.
>> + *
>> + * Author: Shan-Chun Hung <shanchun1218@gmail.com>
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/dma-mapping.h>
>> +#include <linux/mfd/syscon.h>
>> +#include <linux/module.h>
>> +#include <linux/mmc/mmc.h>
>> +#include <linux/pinctrl/consumer.h>
>> +#include <linux/regmap.h>
>> +#include <linux/reset.h>
>> +#include <linux/slab.h>
>> +#include "sdhci-pltfm.h"
>> +
>> +#define MA35_SYS_MISCFCR0    0x070
>> +#define MA35_SDHCI_MSHCCTL    0x508
>> +#define MA35_SDHCI_MBIUCTL    0x510
>> +
>> +#define MA35_SDHCI_CMD_CONFLICT_CHK    BIT(0)
>> +#define MA35_SDHCI_INCR_MSK        GENMASK(3, 0)
>> +#define MA35_SDHCI_INCR16        BIT(3)
>> +#define MA35_SDHCI_INCR8        BIT(2)
>> +
>> +#define BOUNDARY_OK(addr, len) \
>> +    ((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1)))
>> +
>> +struct ma35_priv {
>> +    struct regmap        *regmap;
>> +    struct reset_control    *rst;
>> +    struct pinctrl        *pinctrl;
>> +    struct pinctrl_state    *pins_uhs;
>> +    struct pinctrl_state    *pins_default;
>> +};
>> +
>> +struct ma35_restore_data {
>> +    u32    reg;
>> +    u32    width;
>> +};
>> +
>> +static const struct ma35_restore_data restore_data[] = {
>> +    { SDHCI_CLOCK_CONTROL,        32},
>> +    { SDHCI_BLOCK_SIZE,        32},
>> +    { SDHCI_INT_ENABLE,        32},
>> +    { SDHCI_SIGNAL_ENABLE,        32},
>> +    { SDHCI_AUTO_CMD_STATUS,    32},
>> +    { SDHCI_HOST_CONTROL,        32},
>> +    { SDHCI_TIMEOUT_CONTROL,     8},
>> +    { MA35_SDHCI_MSHCCTL,        32},
>> +    { MA35_SDHCI_MBIUCTL,        32},
>> +};
>> +
>> +/*
>> + * If DMA addr spans 128MB boundary, we split the DMA transfer into two
>> + * so that each DMA transfer doesn't exceed the boundary.
>> + */
>> +static void ma35_adma_write_desc(struct sdhci_host *host, void **desc,
>> +                  dma_addr_t addr, int len, unsigned int cmd)
>> +{
>> +    int tmplen, offset;
>> +
>> +    if (likely(!len || BOUNDARY_OK(addr, len))) {
>> +        sdhci_adma_write_desc(host, desc, addr, len, cmd);
>> +        return;
>> +    }
>> +
>> +    offset = addr & (SZ_128M - 1);
>> +    tmplen = SZ_128M - offset;
>> +    sdhci_adma_write_desc(host, desc, addr, tmplen, cmd);
>> +
>> +    addr += tmplen;
>> +    len -= tmplen;
>> +    sdhci_adma_write_desc(host, desc, addr, len, cmd);
>> +}
>> +
>> +static void ma35_set_clock(struct sdhci_host *host, unsigned int clock)
>> +{
>> +    u32 ctl;
>> +
>> +    /* If the clock frequency exceeds MMC_HIGH_52_MAX_DTR,
>> +     *    disable command conflict check.
>> +     */
>> +    ctl = sdhci_readw(host, MA35_SDHCI_MSHCCTL);
>> +    if (clock > MMC_HIGH_52_MAX_DTR)
>> +        ctl &= ~MA35_SDHCI_CMD_CONFLICT_CHK;
>> +    else
>> +        ctl |= MA35_SDHCI_CMD_CONFLICT_CHK;
>> +    sdhci_writew(host, ctl, MA35_SDHCI_MSHCCTL);
>> +
>> +    sdhci_set_clock(host, clock);
>> +}
>> +
>> +static int ma35_start_signal_voltage_switch(struct mmc_host *mmc,
>> +                          struct mmc_ios *ios)
>> +{
>> +    struct sdhci_host *host = mmc_priv(mmc);
>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>> +    struct ma35_priv *priv = sdhci_pltfm_priv(pltfm_host);
>> +
>> +    switch (ios->signal_voltage) {
>> +    case MMC_SIGNAL_VOLTAGE_180:
>> +        if (!IS_ERR(priv->pinctrl) && !IS_ERR(priv->pins_uhs))
>> +            pinctrl_select_state(priv->pinctrl, priv->pins_uhs);
>> +        break;
>> +    case MMC_SIGNAL_VOLTAGE_330:
>> +        if (!IS_ERR(priv->pinctrl) && !IS_ERR(priv->pins_default))
>> +            pinctrl_select_state(priv->pinctrl, priv->pins_default);
>> +        break;
>> +    default:
>> +        dev_err(mmc_dev(host->mmc), "Unsupported signal voltage!\n");
>> +        return -EINVAL;
>> +    }
>> +
>> +    return sdhci_start_signal_voltage_switch(mmc, ios);
>> +}
>> +
>> +static void ma35_voltage_switch(struct sdhci_host *host)
>> +{
>> +    /* Wait for 5ms after set 1.8V signal enable bit */
>> +    usleep_range(5000, 5500);
>> +}
>> +
>> +static int ma35_execute_tuning(struct mmc_host *mmc, u32 opcode)
>> +{
>> +    struct sdhci_host *host = mmc_priv(mmc);
>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>> +    struct ma35_priv *priv = sdhci_pltfm_priv(pltfm_host);
>> +
>> +    /* Limitations require a reset SD/eMMC before tuning. */
>> +    if (!IS_ERR(priv->rst)) {
>> +        int idx;
>> +        u32 *val;
>> +
>> +        val = kmalloc(ARRAY_SIZE(restore_data), GFP_KERNEL);
>> +        for (idx = 0; idx < ARRAY_SIZE(restore_data); idx++) {
>> +            if (restore_data[idx].width == 32)
>> +                val[idx] = sdhci_readl(host, restore_data[idx].reg);
>> +            else if (restore_data[idx].width == 8)
>> +                val[idx] = sdhci_readb(host, restore_data[idx].reg);
>> +        }
>> +
>> +        reset_control_assert(priv->rst);
>> +        reset_control_deassert(priv->rst);
>> +
>> +        for (idx = 0; idx < ARRAY_SIZE(restore_data); idx++) {
>> +            if (restore_data[idx].width == 32)
>> +                sdhci_writel(host, val[idx], restore_data[idx].reg);
>> +            else if (restore_data[idx].width == 8)
>> +                sdhci_writeb(host, val[idx], restore_data[idx].reg);
>> +        }
>> +
>> +        kfree(val);
>> +    }
>> +
>> +    return sdhci_execute_tuning(mmc, opcode);
>> +}
>> +
>> +static const struct sdhci_ops sdhci_ma35_ops = {
>> +    .set_clock        = ma35_set_clock,
>> +    .set_bus_width        = sdhci_set_bus_width,
>> +    .set_uhs_signaling    = sdhci_set_uhs_signaling,
>> +    .get_max_clock        = sdhci_pltfm_clk_get_max_clock,
>> +    .reset            = sdhci_reset,
>> +    .adma_write_desc    = ma35_adma_write_desc,
>> +    .voltage_switch    = ma35_voltage_switch,
>> +};
>> +
>> +static const struct sdhci_pltfm_data sdhci_ma35_pdata = {
>> +    .ops = &sdhci_ma35_ops,
>> +    .quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
>> +    .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN | 
>> SDHCI_QUIRK2_BROKEN_DDR50 |
>> +           SDHCI_QUIRK2_ACMD23_BROKEN,
>> +};
>> +
>> +static int ma35_probe(struct platform_device *pdev)
>> +{
>> +    struct device *dev = &pdev->dev;
>> +    struct sdhci_pltfm_host *pltfm_host;
>> +    struct sdhci_host *host;
>> +    struct ma35_priv *priv;
>> +    int err;
>> +    u32 extra, ctl;
>> +
>> +    host = sdhci_pltfm_init(pdev, &sdhci_ma35_pdata,
>> +                sizeof(struct ma35_priv));
>> +    if (IS_ERR(host))
>> +        return PTR_ERR(host);
>> +
>> +    /*
>> +     * extra adma table cnt for cross 128M boundary handling.
>> +     */
>> +    extra = DIV_ROUND_UP_ULL(dma_get_required_mask(&pdev->dev), 
>> SZ_128M);
>> +    if (extra > SDHCI_MAX_SEGS)
>> +        extra = SDHCI_MAX_SEGS;
>> +    host->adma_table_cnt += extra;
>> +    pltfm_host = sdhci_priv(host);
>> +    priv = sdhci_pltfm_priv(pltfm_host);
>> +
>> +    if (dev->of_node) {
>> +        pltfm_host->clk = devm_clk_get(&pdev->dev, NULL);
>> +        if (IS_ERR(pltfm_host->clk)) {
>> +            err = PTR_ERR(pltfm_host->clk);
>> +            dev_err(&pdev->dev, "failed to get clk: %d\n", err);
>> +            goto free_pltfm;
>> +        }
>> +        err = clk_prepare_enable(pltfm_host->clk);
>> +        if (err)
>> +            goto free_pltfm;
>> +    }
>> +
>> +    err = mmc_of_parse(host->mmc);
>> +    if (err)
>> +        goto err_clk;
>> +
>> +    priv->rst = devm_reset_control_get(&pdev->dev, NULL);
>> +
>> +    sdhci_get_of_property(pdev);
>> +
>> +    priv->pinctrl = devm_pinctrl_get(&pdev->dev);
>> +    if (!IS_ERR(priv->pinctrl)) {
>> +        priv->pins_default = pinctrl_lookup_state(priv->pinctrl, 
>> "default");
>> +        priv->pins_uhs = pinctrl_lookup_state(priv->pinctrl, 
>> "state_uhs");
>> +        pinctrl_select_state(priv->pinctrl, priv->pins_default);
>> +    }
>> +
>> +    if (!(host->quirks2 & SDHCI_QUIRK2_NO_1_8_V)) {
>> +        u32 reg;
>> +
>> +        priv->regmap = syscon_regmap_lookup_by_phandle(
>> +                pdev->dev.of_node, "nuvoton,sys");
>> +
>> +        if (!IS_ERR(priv->regmap)) {
>> +            /* Enable SDHCI voltage stable for 1.8V */
>> +            regmap_read(priv->regmap, MA35_SYS_MISCFCR0, &reg);
>> +            reg |= BIT(17);
>> +            regmap_write(priv->regmap, MA35_SYS_MISCFCR0, reg);
>> +        }
>> +
>> +        host->mmc_host_ops.start_signal_voltage_switch =
>> +                    ma35_start_signal_voltage_switch;
>> +    }
>> +
>> +    host->mmc_host_ops.execute_tuning = ma35_execute_tuning;
>> +
>> +    err = sdhci_add_host(host);
>> +    if (err)
>> +        goto err_clk;
>> +
>> +    /* Enable INCR16 and INCR8 */
>> +    ctl = sdhci_readw(host, MA35_SDHCI_MBIUCTL);
>> +    ctl &= ~MA35_SDHCI_INCR_MSK;
>> +    ctl |= MA35_SDHCI_INCR16|MA35_SDHCI_INCR8;
>> +    sdhci_writew(host, ctl, MA35_SDHCI_MBIUCTL);
>> +
>> +    return 0;
>> +
>> +err_clk:
>> +    clk_disable_unprepare(pltfm_host->clk);
>> +
>> +free_pltfm:
>> +    sdhci_pltfm_free(pdev);
>> +    return err;
>> +}
>> +
>> +static int ma35_remove(struct platform_device *pdev)
>> +{
>> +    struct sdhci_host *host = platform_get_drvdata(pdev);
>> +    struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>> +
>> +    sdhci_remove_host(host, 0);
>> +    clk_disable_unprepare(pltfm_host->clk);
>> +    sdhci_pltfm_free(pdev);
>> +
>> +    return 0;
>> +}
>> +
>> +static const struct of_device_id sdhci_ma35_dt_ids[] = {
>> +    { .compatible = "nuvoton,ma35d1-sdhci" },
>> +    {}
>> +};
>> +
>> +static struct platform_driver sdhci_ma35_driver = {
>> +    .driver    = {
>> +        .name    = "sdhci-ma35",
>> +        .of_match_table = sdhci_ma35_dt_ids,
>> +    },
>> +    .probe    = ma35_probe,
>> +    .remove = ma35_remove,
>> +};
>> +module_platform_driver(sdhci_ma35_driver);
>> +
>> +MODULE_DESCRIPTION("SDHCI platform driver for Nuvoton ma35d1");
>> +MODULE_AUTHOR("shanchun1218@google.com");
>> +MODULE_LICENSE("GPL v2");
>> -- 
>> 2.25.1