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

Yixun Lan
2025-05-01T08:51:01Z

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)
+{
+ 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),
+ },
+ .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