Re: [PATCH v2 2/2] mmc: sdhci-of-k1: add support for SpacemiT K1 SoC

Inochi Amaoto
2025-05-06T22:37:30Z

On Thu, May 01, 2025 at 04:50:22PM +0800, Yixun Lan wrote:
> The SDHCI controller found in SpacemiT K1 SoC features SD,
> SDIO, eMMC support, such as:
>
> - Compatible for 4-bit SDIO 3.0 UHS-I protocol, up to SDR104
> - Compatible for 4-bit SD 3.0 UHS-I protocol, up to SDR104
> - Compatible for 8bit eMMC5.1, up to HS400
>
> Signed-off-by: Yixun Lan <dlan@gentoo.org>
> ---
> drivers/mmc/host/Kconfig | 14 ++
> drivers/mmc/host/Makefile | 1 +
> drivers/mmc/host/sdhci-of-k1.c | 306 +++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 321 insertions(+)
>
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index 6824131b69b188cae58c8f48076715ca647ca28c..0ce78f22c33cfff916a2d4d680c79e9d19637e0e 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -250,6 +250,20 @@ config MMC_SDHCI_OF_DWCMSHC
> If you have a controller with this interface, say Y or M here.
> If unsure, say N.
>
> +config MMC_SDHCI_OF_K1
> + tristate "SDHCI OF support for the SpacemiT K1 SoC"
> + depends on ARCH_SPACEMIT || COMPILE_TEST
> + depends on MMC_SDHCI_PLTFM
> + depends on OF
> + depends on COMMON_CLK
> + help
> + This selects the Secure Digital Host Controller Interface (SDHCI)
> + found in the SpacemiT K1 SoC.
> +
> + If you have a controller with this interface, say Y or M here.
> +
> + If unsure, say N.
> +
> config MMC_SDHCI_OF_SPARX5
> tristate "SDHCI OF support for the MCHP Sparx5 SoC"
> depends on MMC_SDHCI_PLTFM
> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> index 5147467ec825ffaef3a7bd812fad80545e52b180..75bafc7b162b9e1d4c6c050f5d28b9d7cb582447 100644
> --- a/drivers/mmc/host/Makefile
> +++ b/drivers/mmc/host/Makefile
> @@ -88,6 +88,7 @@ obj-$(CONFIG_MMC_SDHCI_OF_AT91) += sdhci-of-at91.o
> obj-$(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-$(CONFIG_MMC_SDHCI_OF_K1) += sdhci-of-k1.o
> obj-$(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
> diff --git a/drivers/mmc/host/sdhci-of-k1.c b/drivers/mmc/host/sdhci-of-k1.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..8988053eeb33a476fa484d145579db6214b2d0b7
> --- /dev/null
> +++ b/drivers/mmc/host/sdhci-of-k1.c
> @@ -0,0 +1,306 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2023-2025 SpacemiT (Hangzhou) Technology Co. Ltd
> + * Copyright (c) 2025 Yixun Lan <dlan@gentoo.org>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/iopoll.h>
> +#include <linux/init.h>
> +#include <linux/mmc/card.h>
> +#include <linux/mmc/host.h>
> +#include <linux/mmc/mmc.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +
> +#include "sdhci.h"
> +#include "sdhci-pltfm.h"
> +
> +#define SDHC_MMC_CTRL_REG 0x114
> +#define MISC_INT_EN BIT(1)
> +#define MISC_INT BIT(2)
> +#define ENHANCE_STROBE_EN BIT(8)
> +#define MMC_HS400 BIT(9)
> +#define MMC_HS200 BIT(10)
> +#define MMC_CARD_MODE BIT(12)
> +
> +#define SDHC_TX_CFG_REG 0x11C
> +#define TX_INT_CLK_SEL BIT(30)
> +#define TX_MUX_SEL BIT(31)
> +
> +#define SDHC_PHY_CTRL_REG 0x160
> +#define PHY_FUNC_EN BIT(0)
> +#define PHY_PLL_LOCK BIT(1)
> +#define HOST_LEGACY_MODE BIT(31)
> +
> +#define SDHC_PHY_FUNC_REG 0x164
> +#define PHY_TEST_EN BIT(7)
> +#define HS200_USE_RFIFO BIT(15)
> +
> +#define SDHC_PHY_DLLCFG 0x168
> +#define DLL_PREDLY_NUM GENMASK(3, 2)
> +#define DLL_FULLDLY_RANGE GENMASK(5, 4)
> +#define DLL_VREG_CTRL GENMASK(7, 6)
> +#define DLL_ENABLE BIT(31)
> +
> +#define SDHC_PHY_DLLCFG1 0x16C
> +#define DLL_REG1_CTRL GENMASK(7, 0)
> +#define DLL_REG2_CTRL GENMASK(15, 8)
> +#define DLL_REG3_CTRL GENMASK(23, 16)
> +#define DLL_REG4_CTRL GENMASK(31, 24)
> +
> +#define SDHC_PHY_DLLSTS 0x170
> +#define DLL_LOCK_STATE BIT(0)
> +
> +#define SDHC_PHY_PADCFG_REG 0x178
> +#define PHY_DRIVE_SEL GENMASK(2, 0)
> +#define RX_BIAS_CTRL BIT(5)
> +
> +struct spacemit_sdhci_host {
> + struct clk *clk_core;
> + struct clk *clk_io;
> +};
> +
> +static inline void spacemit_sdhci_setbits(struct sdhci_host *host, u32 val, int reg)
> +{
> + sdhci_writel(host, sdhci_readl(host, reg) | val, reg);
> +}
> +
> +static inline void spacemit_sdhci_clrbits(struct sdhci_host *host, u32 val, int reg)
> +{
> + sdhci_writel(host, sdhci_readl(host, reg) & ~val, reg);
> +}
> +

> +static inline void spacemit_sdhci_clrsetbits(struct sdhci_host *host, u32 clr, u32 set, int reg)

updatebits?

> +{
> + u32 val = sdhci_readl(host, reg);
> +
> + val = (val & ~clr) | set;
> + sdhci_writel(host, val, reg);
> +}
> +
> +static void spacemit_sdhci_reset(struct sdhci_host *host, u8 mask)
> +{
> + struct platform_device *pdev;
> +
> + pdev = to_platform_device(mmc_dev(host->mmc));
> + sdhci_reset(host, mask);
> +
> + if (mask != SDHCI_RESET_ALL)
> + return;
> +
> + spacemit_sdhci_setbits(host, PHY_FUNC_EN | PHY_PLL_LOCK, SDHC_PHY_CTRL_REG);
> +
> + spacemit_sdhci_clrsetbits(host, PHY_DRIVE_SEL,
> + RX_BIAS_CTRL | FIELD_PREP(PHY_DRIVE_SEL, 4),
> + SDHC_PHY_PADCFG_REG);
> +
> + if (!(host->mmc->caps2 & MMC_CAP2_NO_MMC))
> + spacemit_sdhci_setbits(host, MMC_CARD_MODE, SDHC_MMC_CTRL_REG);
> +}
> +
> +static void spacemit_sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned int timing)
> +{
> + if (timing == MMC_TIMING_MMC_HS200)
> + spacemit_sdhci_setbits(host, MMC_HS200, SDHC_MMC_CTRL_REG);
> +
> + if (timing == MMC_TIMING_MMC_HS400)
> + spacemit_sdhci_setbits(host, MMC_HS400, SDHC_MMC_CTRL_REG);
> +
> + sdhci_set_uhs_signaling(host, timing);
> +
> + if (!(host->mmc->caps2 & MMC_CAP2_NO_SDIO))
> + spacemit_sdhci_setbits(host, SDHCI_CTRL_VDD_180, SDHCI_HOST_CONTROL2);
> +}
> +
> +static void spacemit_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
> +{
> + struct mmc_host *mmc = host->mmc;
> +
> + if (mmc->ios.timing <= MMC_TIMING_UHS_SDR50)
> + spacemit_sdhci_setbits(host, TX_INT_CLK_SEL, SDHC_TX_CFG_REG);
> + else
> + spacemit_sdhci_clrbits(host, TX_INT_CLK_SEL, SDHC_TX_CFG_REG);
> +
> + sdhci_set_clock(host, clock);
> +};
> +
> +static void spacemit_sdhci_phy_dll_init(struct sdhci_host *host)
> +{
> + u32 state;
> + int ret;
> +
> + spacemit_sdhci_clrsetbits(host, DLL_PREDLY_NUM | DLL_FULLDLY_RANGE | DLL_VREG_CTRL,
> + FIELD_PREP(DLL_PREDLY_NUM, 1) |
> + FIELD_PREP(DLL_FULLDLY_RANGE, 1) |
> + FIELD_PREP(DLL_VREG_CTRL, 1),
> + SDHC_PHY_DLLCFG);
> +
> + spacemit_sdhci_clrsetbits(host, DLL_REG1_CTRL,
> + FIELD_PREP(DLL_REG1_CTRL, 0x92),
> + SDHC_PHY_DLLCFG1);
> +
> + spacemit_sdhci_setbits(host, DLL_ENABLE, SDHC_PHY_DLLCFG);
> +
> + ret = readl_poll_timeout(host->ioaddr + SDHC_PHY_DLLSTS, state,
> + state & DLL_LOCK_STATE, 2, 100);
> + if (ret == -ETIMEDOUT)
> + dev_warn(mmc_dev(host->mmc), "fail to lock phy dll in 100us!\n");
> +}
> +
> +static void spacemit_sdhci_hs400_enhanced_strobe(struct mmc_host *mmc, struct mmc_ios *ios)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> +
> + if (!ios->enhanced_strobe) {
> + spacemit_sdhci_clrbits(host, ENHANCE_STROBE_EN, SDHC_MMC_CTRL_REG);
> + return;
> + }
> +
> + spacemit_sdhci_setbits(host, ENHANCE_STROBE_EN, SDHC_MMC_CTRL_REG);
> + spacemit_sdhci_phy_dll_init(host);
> +}
> +
> +static unsigned int spacemit_sdhci_clk_get_max_clock(struct sdhci_host *host)
> +{
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +
> + return clk_get_rate(pltfm_host->clk);
> +}
> +
> +static int spacemit_sdhci_pre_select_hs400(struct mmc_host *mmc)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> +
> + spacemit_sdhci_setbits(host, MMC_HS400, SDHC_MMC_CTRL_REG);
> + host->mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY;
> +
> + return 0;
> +}
> +
> +static void spacemit_sdhci_post_select_hs400(struct mmc_host *mmc)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> +
> + spacemit_sdhci_phy_dll_init(host);
> + host->mmc->caps &= ~MMC_CAP_WAIT_WHILE_BUSY;
> +}
> +
> +static void spacemit_sdhci_pre_hs400_to_hs200(struct mmc_host *mmc)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> +
> + spacemit_sdhci_clrbits(host, PHY_FUNC_EN | PHY_PLL_LOCK, SDHC_PHY_CTRL_REG);
> + spacemit_sdhci_clrbits(host, MMC_HS400 | MMC_HS200 | ENHANCE_STROBE_EN, SDHC_MMC_CTRL_REG);
> + spacemit_sdhci_clrbits(host, HS200_USE_RFIFO, SDHC_PHY_FUNC_REG);
> +
> + udelay(5);
> +
> + spacemit_sdhci_setbits(host, PHY_FUNC_EN | PHY_PLL_LOCK, SDHC_PHY_CTRL_REG);
> +}
> +
> +static inline int spacemit_sdhci_get_clocks(struct device *dev,
> + struct sdhci_pltfm_host *pltfm_host)
> +{
> + struct spacemit_sdhci_host *sdhst = sdhci_pltfm_priv(pltfm_host);
> +
> + sdhst->clk_core = devm_clk_get_enabled(dev, "core");
> + if (IS_ERR(sdhst->clk_core))
> + return -EINVAL;
> +
> + sdhst->clk_io = devm_clk_get_enabled(dev, "io");
> + if (IS_ERR(sdhst->clk_io))
> + return -EINVAL;
> +
> + pltfm_host->clk = sdhst->clk_io;
> +
> + return 0;
> +}
> +
> +static const struct sdhci_ops spacemit_sdhci_ops = {
> + .get_max_clock = spacemit_sdhci_clk_get_max_clock,
> + .reset = spacemit_sdhci_reset,
> + .set_bus_width = sdhci_set_bus_width,
> + .set_clock = spacemit_sdhci_set_clock,
> + .set_uhs_signaling = spacemit_sdhci_set_uhs_signaling,
> +};
> +
> +static const struct sdhci_pltfm_data spacemit_sdhci_k1_pdata = {
> + .ops = &spacemit_sdhci_ops,
> + .quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
> + SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC |
> + SDHCI_QUIRK_32BIT_ADMA_SIZE |
> + SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN |
> + SDHCI_QUIRK_BROKEN_CARD_DETECTION |
> + SDHCI_QUIRK_BROKEN_TIMEOUT_VAL,
> + .quirks2 = SDHCI_QUIRK2_BROKEN_64_BIT_DMA |
> + SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
> +};
> +
> +static const struct of_device_id spacemit_sdhci_of_match[] = {
> + { .compatible = "spacemit,k1-sdhci" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, spacemit_sdhci_of_match);
> +
> +static int spacemit_sdhci_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct spacemit_sdhci_host *sdhst;
> + struct sdhci_pltfm_host *pltfm_host;
> + struct sdhci_host *host;
> + struct mmc_host_ops *mops;
> + int ret;
> +
> + host = sdhci_pltfm_init(pdev, &spacemit_sdhci_k1_pdata, sizeof(*sdhst));
> + if (IS_ERR(host))
> + return PTR_ERR(host);
> +
> + pltfm_host = sdhci_priv(host);
> +
> + ret = mmc_of_parse(host->mmc);
> + if (ret)
> + goto err_pltfm;
> +
> + sdhci_get_of_property(pdev);
> +
> + if (!(host->mmc->caps2 & MMC_CAP2_NO_MMC)) {
> + mops = &host->mmc_host_ops;
> + mops->hs400_prepare_ddr = spacemit_sdhci_pre_select_hs400;
> + mops->hs400_complete = spacemit_sdhci_post_select_hs400;
> + mops->hs400_downgrade = spacemit_sdhci_pre_hs400_to_hs200;
> + mops->hs400_enhanced_strobe = spacemit_sdhci_hs400_enhanced_strobe;
> + }
> +
> + host->mmc->caps |= MMC_CAP_NEED_RSP_BUSY;
> +
> + if (spacemit_sdhci_get_clocks(dev, pltfm_host))
> + goto err_pltfm;
> +
> + ret = sdhci_add_host(host);
> + if (ret)
> + goto err_pltfm;
> +
> + return 0;
> +
> +err_pltfm:
> + sdhci_pltfm_free(pdev);
> + return ret;
> +}
> +
> +static struct platform_driver spacemit_sdhci_driver = {
> + .driver = {
> + .name = "sdhci-spacemit",

> + .of_match_table = of_match_ptr(spacemit_sdhci_of_match),

I think the of_match_ptr is not needed.

> + },
> + .probe = spacemit_sdhci_probe,
> + .remove = sdhci_pltfm_remove,
> +};
> +module_platform_driver(spacemit_sdhci_driver);
> +
> +MODULE_DESCRIPTION("SpacemiT SDHCI platform driver");
> +MODULE_LICENSE("GPL");
>
> --
> 2.49.0
>