--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2024 Nuvoton Technology Corp.
+ *
+ * Author: Shan-Chun Hung <shanchun1218@gmail.com>
+ */
+
+#include <linux/align.h>
+#include <linux/array_size.h>
+#include <linux/bits.h>
+#include <linux/build_bug.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dev_printk.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/math.h>
+#include <linux/mfd/syscon.h>
+#include <linux/minmax.h>
+#include <linux/mmc/card.h>
+#include <linux/mmc/host.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/sizes.h>
+#include <linux/types.h>
+
+#include "sdhci-pltfm.h"
+#include "sdhci.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)
+
+struct ma35_priv {
+ 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, sizeof(u32)},
+ { SDHCI_BLOCK_SIZE, sizeof(u32)},
+ { SDHCI_INT_ENABLE, sizeof(u32)},
+ { SDHCI_SIGNAL_ENABLE, sizeof(u32)},
+ { SDHCI_AUTO_CMD_STATUS, sizeof(u32)},
+ { SDHCI_HOST_CONTROL, sizeof(u32)},
+ { SDHCI_TIMEOUT_CONTROL, sizeof(u8) },
+ { MA35_SDHCI_MSHCCTL, sizeof(u16)},
+ { MA35_SDHCI_MBIUCTL, sizeof(u16)},
+};
+
+/*
+ * 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 || (ALIGN(addr, SZ_128M) == ALIGN(addr + len - 1, SZ_128M)))) {
+ 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 */
+ fsleep(5000);
+}
+
+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);
+ int idx;
+ u32 regs[ARRAY_SIZE(restore_data)] = {};
+
+ /*
+ * Limitations require a reset of SD/eMMC before tuning and
+ * saving the registers before resetting, then restoring
+ * after the reset.
+ */
+ for (idx = 0; idx < ARRAY_SIZE(restore_data); idx++) {
+ if (restore_data[idx].width == sizeof(u32))
+ regs[idx] = sdhci_readl(host, restore_data[idx].reg);
+ else if (restore_data[idx].width == sizeof(u16))
+ regs[idx] = sdhci_readw(host, restore_data[idx].reg);
+ else if (restore_data[idx].width == sizeof(u8))
+ regs[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 == sizeof(u32))
+ sdhci_writel(host, regs[idx], restore_data[idx].reg);
+ else if (restore_data[idx].width == sizeof(u16))
+ sdhci_writew(host, regs[idx], restore_data[idx].reg);
+ else if (restore_data[idx].width == sizeof(u8))
+ sdhci_writeb(host, regs[idx], restore_data[idx].reg);
+ }
+
+ 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(dev), SZ_128M);
+ extra = min(extra, SDHCI_MAX_SEGS);
+
+ host->adma_table_cnt += extra;
+ pltfm_host = sdhci_priv(host);
+ priv = sdhci_pltfm_priv(pltfm_host);
+
+ pltfm_host->clk = devm_clk_get_optional_enabled(dev, NULL);
+ if (IS_ERR(pltfm_host->clk)) {
+ err = dev_err_probe(dev, PTR_ERR(pltfm_host->clk), "failed to get clk\n");
+ goto err_sdhci;
+ }
+
+ err = mmc_of_parse(host->mmc);
+ if (err)
+ goto err_sdhci;
+
+ priv->rst = devm_reset_control_get_exclusive(dev, NULL);
+ if (IS_ERR(priv->rst)) {
+ err = dev_err_probe(dev, PTR_ERR(priv->rst), "failed to get reset control\n");
+ goto err_sdhci;
+ }
+
+ sdhci_get_of_property(pdev);
+
+ priv->pinctrl = devm_pinctrl_get(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)) {
+ struct regmap *regmap;
+ u32 reg;
+
+ regmap = syscon_regmap_lookup_by_phandle(dev_of_node(dev), "nuvoton,sys");
+ if (!IS_ERR(regmap)) {
+ /* Enable SDHCI voltage stable for 1.8V */
+ regmap_read(regmap, MA35_SYS_MISCFCR0, ®);
+ reg |= BIT(17);
+ regmap_write(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_sdhci;
+
+ /*
+ * Split data into chunks of 16 or 8 bytes for transmission.
+ * Each chunk transfer is guaranteed to be uninterrupted on the bus.
+ * This likely corresponds to the AHB bus DMA burst size.
+ */
+ 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_sdhci:
+ sdhci_pltfm_free(pdev);
+ return err;
+}
+
+static void ma35_disable_card_clk(struct sdhci_host *host)
+{
+ u16 ctrl;
+
+ ctrl = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+ if (ctrl & SDHCI_CLOCK_CARD_EN) {
+ ctrl &= ~SDHCI_CLOCK_CARD_EN;
+ sdhci_writew(host, ctrl, SDHCI_CLOCK_CONTROL);
+ }
+}
+
+static void ma35_remove(struct platform_device *pdev)
+{
+ struct sdhci_host *host = platform_get_drvdata(pdev);
+
+ sdhci_remove_host(host, 0);
+ ma35_disable_card_clk(host);
+ sdhci_pltfm_free(pdev);
+}
+
+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_new = ma35_remove,
+};
+module_platform_driver(sdhci_ma35_driver);
+
+MODULE_DESCRIPTION("SDHCI platform driver for Nuvoton MA35");
+MODULE_AUTHOR("Shan-Chun Hung <shanchun1218@gmail.com>");
+MODULE_LICENSE("GPL");
projects / thirdparty / kernel / linux.git / commitdiff
