1 files changed, 542 insertions, 0 deletions

diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c
new file mode 100644
index 000000000..4cceb9bab
--- /dev/null
+++ b/drivers/mmc/host/mmci_stm32_sdmmc.c
@@ -0,0 +1,542 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics 2018 - All Rights Reserved
+ * Author: Ludovic.barre@st.com for STMicroelectronics.
+ */
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/iopoll.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include <linux/of_address.h>
+#include <linux/reset.h>
+#include <linux/scatterlist.h>
+#include "mmci.h"
+
+#define SDMMC_LLI_BUF_LEN	PAGE_SIZE
+#define SDMMC_IDMA_BURST	BIT(MMCI_STM32_IDMABNDT_SHIFT)
+
+#define DLYB_CR			0x0
+#define DLYB_CR_DEN		BIT(0)
+#define DLYB_CR_SEN		BIT(1)
+
+#define DLYB_CFGR		0x4
+#define DLYB_CFGR_SEL_MASK	GENMASK(3, 0)
+#define DLYB_CFGR_UNIT_MASK	GENMASK(14, 8)
+#define DLYB_CFGR_LNG_MASK	GENMASK(27, 16)
+#define DLYB_CFGR_LNGF		BIT(31)
+
+#define DLYB_NB_DELAY		11
+#define DLYB_CFGR_SEL_MAX	(DLYB_NB_DELAY + 1)
+#define DLYB_CFGR_UNIT_MAX	127
+
+#define DLYB_LNG_TIMEOUT_US	1000
+#define SDMMC_VSWEND_TIMEOUT_US 10000
+
+struct sdmmc_lli_desc {
+	u32 idmalar;
+	u32 idmabase;
+	u32 idmasize;
+};
+
+struct sdmmc_idma {
+	dma_addr_t sg_dma;
+	void *sg_cpu;
+};
+
+struct sdmmc_dlyb {
+	void __iomem *base;
+	u32 unit;
+	u32 max;
+};
+
+static int sdmmc_idma_validate_data(struct mmci_host *host,
+				    struct mmc_data *data)
+{
+	struct scatterlist *sg;
+	int i;
+
+	/*
+	 * idma has constraints on idmabase & idmasize for each element
+	 * excepted the last element which has no constraint on idmasize
+	 */
+	for_each_sg(data->sg, sg, data->sg_len - 1, i) {
+		if (!IS_ALIGNED(sg->offset, sizeof(u32)) ||
+		    !IS_ALIGNED(sg->length, SDMMC_IDMA_BURST)) {
+			dev_err(mmc_dev(host->mmc),
+				"unaligned scatterlist: ofst:%x length:%d\n",
+				data->sg->offset, data->sg->length);
+			return -EINVAL;
+		}
+	}
+
+	if (!IS_ALIGNED(sg->offset, sizeof(u32))) {
+		dev_err(mmc_dev(host->mmc),
+			"unaligned last scatterlist: ofst:%x length:%d\n",
+			data->sg->offset, data->sg->length);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int _sdmmc_idma_prep_data(struct mmci_host *host,
+				 struct mmc_data *data)
+{
+	int n_elem;
+
+	n_elem = dma_map_sg(mmc_dev(host->mmc),
+			    data->sg,
+			    data->sg_len,
+			    mmc_get_dma_dir(data));
+
+	if (!n_elem) {
+		dev_err(mmc_dev(host->mmc), "dma_map_sg failed\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int sdmmc_idma_prep_data(struct mmci_host *host,
+				struct mmc_data *data, bool next)
+{
+	/* Check if job is already prepared. */
+	if (!next && data->host_cookie == host->next_cookie)
+		return 0;
+
+	return _sdmmc_idma_prep_data(host, data);
+}
+
+static void sdmmc_idma_unprep_data(struct mmci_host *host,
+				   struct mmc_data *data, int err)
+{
+	dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
+		     mmc_get_dma_dir(data));
+}
+
+static int sdmmc_idma_setup(struct mmci_host *host)
+{
+	struct sdmmc_idma *idma;
+	struct device *dev = mmc_dev(host->mmc);
+
+	idma = devm_kzalloc(dev, sizeof(*idma), GFP_KERNEL);
+	if (!idma)
+		return -ENOMEM;
+
+	host->dma_priv = idma;
+
+	if (host->variant->dma_lli) {
+		idma->sg_cpu = dmam_alloc_coherent(dev, SDMMC_LLI_BUF_LEN,
+						   &idma->sg_dma, GFP_KERNEL);
+		if (!idma->sg_cpu) {
+			dev_err(dev, "Failed to alloc IDMA descriptor\n");
+			return -ENOMEM;
+		}
+		host->mmc->max_segs = SDMMC_LLI_BUF_LEN /
+			sizeof(struct sdmmc_lli_desc);
+		host->mmc->max_seg_size = host->variant->stm32_idmabsize_mask;
+	} else {
+		host->mmc->max_segs = 1;
+		host->mmc->max_seg_size = host->mmc->max_req_size;
+	}
+
+	return dma_set_max_seg_size(dev, host->mmc->max_seg_size);
+}
+
+static int sdmmc_idma_start(struct mmci_host *host, unsigned int *datactrl)
+
+{
+	struct sdmmc_idma *idma = host->dma_priv;
+	struct sdmmc_lli_desc *desc = (struct sdmmc_lli_desc *)idma->sg_cpu;
+	struct mmc_data *data = host->data;
+	struct scatterlist *sg;
+	int i;
+
+	if (!host->variant->dma_lli || data->sg_len == 1) {
+		writel_relaxed(sg_dma_address(data->sg),
+			       host->base + MMCI_STM32_IDMABASE0R);
+		writel_relaxed(MMCI_STM32_IDMAEN,
+			       host->base + MMCI_STM32_IDMACTRLR);
+		return 0;
+	}
+
+	for_each_sg(data->sg, sg, data->sg_len, i) {
+		desc[i].idmalar = (i + 1) * sizeof(struct sdmmc_lli_desc);
+		desc[i].idmalar |= MMCI_STM32_ULA | MMCI_STM32_ULS
+			| MMCI_STM32_ABR;
+		desc[i].idmabase = sg_dma_address(sg);
+		desc[i].idmasize = sg_dma_len(sg);
+	}
+
+	/* notice the end of link list */
+	desc[data->sg_len - 1].idmalar &= ~MMCI_STM32_ULA;
+
+	dma_wmb();
+	writel_relaxed(idma->sg_dma, host->base + MMCI_STM32_IDMABAR);
+	writel_relaxed(desc[0].idmalar, host->base + MMCI_STM32_IDMALAR);
+	writel_relaxed(desc[0].idmabase, host->base + MMCI_STM32_IDMABASE0R);
+	writel_relaxed(desc[0].idmasize, host->base + MMCI_STM32_IDMABSIZER);
+	writel_relaxed(MMCI_STM32_IDMAEN | MMCI_STM32_IDMALLIEN,
+		       host->base + MMCI_STM32_IDMACTRLR);
+
+	return 0;
+}
+
+static void sdmmc_idma_finalize(struct mmci_host *host, struct mmc_data *data)
+{
+	writel_relaxed(0, host->base + MMCI_STM32_IDMACTRLR);
+
+	if (!data->host_cookie)
+		sdmmc_idma_unprep_data(host, data, 0);
+}
+
+static void mmci_sdmmc_set_clkreg(struct mmci_host *host, unsigned int desired)
+{
+	unsigned int clk = 0, ddr = 0;
+
+	if (host->mmc->ios.timing == MMC_TIMING_MMC_DDR52 ||
+	    host->mmc->ios.timing == MMC_TIMING_UHS_DDR50)
+		ddr = MCI_STM32_CLK_DDR;
+
+	/*
+	 * cclk = mclk / (2 * clkdiv)
+	 * clkdiv 0 => bypass
+	 * in ddr mode bypass is not possible
+	 */
+	if (desired) {
+		if (desired >= host->mclk && !ddr) {
+			host->cclk = host->mclk;
+		} else {
+			clk = DIV_ROUND_UP(host->mclk, 2 * desired);
+			if (clk > MCI_STM32_CLK_CLKDIV_MSK)
+				clk = MCI_STM32_CLK_CLKDIV_MSK;
+			host->cclk = host->mclk / (2 * clk);
+		}
+	} else {
+		/*
+		 * while power-on phase the clock can't be define to 0,
+		 * Only power-off and power-cyc deactivate the clock.
+		 * if desired clock is 0, set max divider
+		 */
+		clk = MCI_STM32_CLK_CLKDIV_MSK;
+		host->cclk = host->mclk / (2 * clk);
+	}
+
+	/* Set actual clock for debug */
+	if (host->mmc->ios.power_mode == MMC_POWER_ON)
+		host->mmc->actual_clock = host->cclk;
+	else
+		host->mmc->actual_clock = 0;
+
+	if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_4)
+		clk |= MCI_STM32_CLK_WIDEBUS_4;
+	if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_8)
+		clk |= MCI_STM32_CLK_WIDEBUS_8;
+
+	clk |= MCI_STM32_CLK_HWFCEN;
+	clk |= host->clk_reg_add;
+	clk |= ddr;
+
+	/*
+	 * SDMMC_FBCK is selected when an external Delay Block is needed
+	 * with SDR104.
+	 */
+	if (host->mmc->ios.timing >= MMC_TIMING_UHS_SDR50) {
+		clk |= MCI_STM32_CLK_BUSSPEED;
+		if (host->mmc->ios.timing == MMC_TIMING_UHS_SDR104) {
+			clk &= ~MCI_STM32_CLK_SEL_MSK;
+			clk |= MCI_STM32_CLK_SELFBCK;
+		}
+	}
+
+	mmci_write_clkreg(host, clk);
+}
+
+static void sdmmc_dlyb_input_ck(struct sdmmc_dlyb *dlyb)
+{
+	if (!dlyb || !dlyb->base)
+		return;
+
+	/* Output clock = Input clock */
+	writel_relaxed(0, dlyb->base + DLYB_CR);
+}
+
+static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, unsigned int pwr)
+{
+	struct mmc_ios ios = host->mmc->ios;
+	struct sdmmc_dlyb *dlyb = host->variant_priv;
+
+	/* adds OF options */
+	pwr = host->pwr_reg_add;
+
+	sdmmc_dlyb_input_ck(dlyb);
+
+	if (ios.power_mode == MMC_POWER_OFF) {
+		/* Only a reset could power-off sdmmc */
+		reset_control_assert(host->rst);
+		udelay(2);
+		reset_control_deassert(host->rst);
+
+		/*
+		 * Set the SDMMC in Power-cycle state.
+		 * This will make that the SDMMC_D[7:0], SDMMC_CMD and SDMMC_CK
+		 * are driven low, to prevent the Card from being supplied
+		 * through the signal lines.
+		 */
+		mmci_write_pwrreg(host, MCI_STM32_PWR_CYC | pwr);
+	} else if (ios.power_mode == MMC_POWER_ON) {
+		/*
+		 * After power-off (reset): the irq mask defined in probe
+		 * functionis lost
+		 * ault irq mask (probe) must be activated
+		 */
+		writel(MCI_IRQENABLE | host->variant->start_err,
+		       host->base + MMCIMASK0);
+
+		/* preserves voltage switch bits */
+		pwr |= host->pwr_reg & (MCI_STM32_VSWITCHEN |
+					MCI_STM32_VSWITCH);
+
+		/*
+		 * After a power-cycle state, we must set the SDMMC in
+		 * Power-off. The SDMMC_D[7:0], SDMMC_CMD and SDMMC_CK are
+		 * driven high. Then we can set the SDMMC to Power-on state
+		 */
+		mmci_write_pwrreg(host, MCI_PWR_OFF | pwr);
+		mdelay(1);
+		mmci_write_pwrreg(host, MCI_PWR_ON | pwr);
+	}
+}
+
+static u32 sdmmc_get_dctrl_cfg(struct mmci_host *host)
+{
+	u32 datactrl;
+
+	datactrl = mmci_dctrl_blksz(host);
+
+	if (host->mmc->card && mmc_card_sdio(host->mmc->card) &&
+	    host->data->blocks == 1)
+		datactrl |= MCI_DPSM_STM32_MODE_SDIO;
+	else if (host->data->stop && !host->mrq->sbc)
+		datactrl |= MCI_DPSM_STM32_MODE_BLOCK_STOP;
+	else
+		datactrl |= MCI_DPSM_STM32_MODE_BLOCK;
+
+	return datactrl;
+}
+
+static bool sdmmc_busy_complete(struct mmci_host *host, u32 status, u32 err_msk)
+{
+	void __iomem *base = host->base;
+	u32 busy_d0, busy_d0end, mask, sdmmc_status;
+
+	mask = readl_relaxed(base + MMCIMASK0);
+	sdmmc_status = readl_relaxed(base + MMCISTATUS);
+	busy_d0end = sdmmc_status & MCI_STM32_BUSYD0END;
+	busy_d0 = sdmmc_status & MCI_STM32_BUSYD0;
+
+	/* complete if there is an error or busy_d0end */
+	if ((status & err_msk) || busy_d0end)
+		goto complete;
+
+	/*
+	 * On response the busy signaling is reflected in the BUSYD0 flag.
+	 * if busy_d0 is in-progress we must activate busyd0end interrupt
+	 * to wait this completion. Else this request has no busy step.
+	 */
+	if (busy_d0) {
+		if (!host->busy_status) {
+			writel_relaxed(mask | host->variant->busy_detect_mask,
+				       base + MMCIMASK0);
+			host->busy_status = status &
+				(MCI_CMDSENT | MCI_CMDRESPEND);
+		}
+		return false;
+	}
+
+complete:
+	if (host->busy_status) {
+		writel_relaxed(mask & ~host->variant->busy_detect_mask,
+			       base + MMCIMASK0);
+		host->busy_status = 0;
+	}
+
+	writel_relaxed(host->variant->busy_detect_mask, base + MMCICLEAR);
+
+	return true;
+}
+
+static void sdmmc_dlyb_set_cfgr(struct sdmmc_dlyb *dlyb,
+				int unit, int phase, bool sampler)
+{
+	u32 cfgr;
+
+	writel_relaxed(DLYB_CR_SEN | DLYB_CR_DEN, dlyb->base + DLYB_CR);
+
+	cfgr = FIELD_PREP(DLYB_CFGR_UNIT_MASK, unit) |
+	       FIELD_PREP(DLYB_CFGR_SEL_MASK, phase);
+	writel_relaxed(cfgr, dlyb->base + DLYB_CFGR);
+
+	if (!sampler)
+		writel_relaxed(DLYB_CR_DEN, dlyb->base + DLYB_CR);
+}
+
+static int sdmmc_dlyb_lng_tuning(struct mmci_host *host)
+{
+	struct sdmmc_dlyb *dlyb = host->variant_priv;
+	u32 cfgr;
+	int i, lng, ret;
+
+	for (i = 0; i <= DLYB_CFGR_UNIT_MAX; i++) {
+		sdmmc_dlyb_set_cfgr(dlyb, i, DLYB_CFGR_SEL_MAX, true);
+
+		ret = readl_relaxed_poll_timeout(dlyb->base + DLYB_CFGR, cfgr,
+						 (cfgr & DLYB_CFGR_LNGF),
+						 1, DLYB_LNG_TIMEOUT_US);
+		if (ret) {
+			dev_warn(mmc_dev(host->mmc),
+				 "delay line cfg timeout unit:%d cfgr:%d\n",
+				 i, cfgr);
+			continue;
+		}
+
+		lng = FIELD_GET(DLYB_CFGR_LNG_MASK, cfgr);
+		if (lng < BIT(DLYB_NB_DELAY) && lng > 0)
+			break;
+	}
+
+	if (i > DLYB_CFGR_UNIT_MAX)
+		return -EINVAL;
+
+	dlyb->unit = i;
+	dlyb->max = __fls(lng);
+
+	return 0;
+}
+
+static int sdmmc_dlyb_phase_tuning(struct mmci_host *host, u32 opcode)
+{
+	struct sdmmc_dlyb *dlyb = host->variant_priv;
+	int cur_len = 0, max_len = 0, end_of_len = 0;
+	int phase;
+
+	for (phase = 0; phase <= dlyb->max; phase++) {
+		sdmmc_dlyb_set_cfgr(dlyb, dlyb->unit, phase, false);
+
+		if (mmc_send_tuning(host->mmc, opcode, NULL)) {
+			cur_len = 0;
+		} else {
+			cur_len++;
+			if (cur_len > max_len) {
+				max_len = cur_len;
+				end_of_len = phase;
+			}
+		}
+	}
+
+	if (!max_len) {
+		dev_err(mmc_dev(host->mmc), "no tuning point found\n");
+		return -EINVAL;
+	}
+
+	writel_relaxed(0, dlyb->base + DLYB_CR);
+
+	phase = end_of_len - max_len / 2;
+	sdmmc_dlyb_set_cfgr(dlyb, dlyb->unit, phase, false);
+
+	dev_dbg(mmc_dev(host->mmc), "unit:%d max_dly:%d phase:%d\n",
+		dlyb->unit, dlyb->max, phase);
+
+	return 0;
+}
+
+static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
+{
+	struct mmci_host *host = mmc_priv(mmc);
+	struct sdmmc_dlyb *dlyb = host->variant_priv;
+
+	if (!dlyb || !dlyb->base)
+		return -EINVAL;
+
+	if (sdmmc_dlyb_lng_tuning(host))
+		return -EINVAL;
+
+	return sdmmc_dlyb_phase_tuning(host, opcode);
+}
+
+static void sdmmc_pre_sig_volt_vswitch(struct mmci_host *host)
+{
+	/* clear the voltage switch completion flag */
+	writel_relaxed(MCI_STM32_VSWENDC, host->base + MMCICLEAR);
+	/* enable Voltage switch procedure */
+	mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCHEN);
+}
+
+static int sdmmc_post_sig_volt_switch(struct mmci_host *host,
+				      struct mmc_ios *ios)
+{
+	unsigned long flags;
+	u32 status;
+	int ret = 0;
+
+	spin_lock_irqsave(&host->lock, flags);
+	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180 &&
+	    host->pwr_reg & MCI_STM32_VSWITCHEN) {
+		mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCH);
+		spin_unlock_irqrestore(&host->lock, flags);
+
+		/* wait voltage switch completion while 10ms */
+		ret = readl_relaxed_poll_timeout(host->base + MMCISTATUS,
+						 status,
+						 (status & MCI_STM32_VSWEND),
+						 10, SDMMC_VSWEND_TIMEOUT_US);
+
+		writel_relaxed(MCI_STM32_VSWENDC | MCI_STM32_CKSTOPC,
+			       host->base + MMCICLEAR);
+		spin_lock_irqsave(&host->lock, flags);
+		mmci_write_pwrreg(host, host->pwr_reg &
+				  ~(MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
+	}
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	return ret;
+}
+
+static struct mmci_host_ops sdmmc_variant_ops = {
+	.validate_data = sdmmc_idma_validate_data,
+	.prep_data = sdmmc_idma_prep_data,
+	.unprep_data = sdmmc_idma_unprep_data,
+	.get_datactrl_cfg = sdmmc_get_dctrl_cfg,
+	.dma_setup = sdmmc_idma_setup,
+	.dma_start = sdmmc_idma_start,
+	.dma_finalize = sdmmc_idma_finalize,
+	.set_clkreg = mmci_sdmmc_set_clkreg,
+	.set_pwrreg = mmci_sdmmc_set_pwrreg,
+	.busy_complete = sdmmc_busy_complete,
+	.pre_sig_volt_switch = sdmmc_pre_sig_volt_vswitch,
+	.post_sig_volt_switch = sdmmc_post_sig_volt_switch,
+};
+
+void sdmmc_variant_init(struct mmci_host *host)
+{
+	struct device_node *np = host->mmc->parent->of_node;
+	void __iomem *base_dlyb;
+	struct sdmmc_dlyb *dlyb;
+
+	host->ops = &sdmmc_variant_ops;
+	host->pwr_reg = readl_relaxed(host->base + MMCIPOWER);
+
+	base_dlyb = devm_of_iomap(mmc_dev(host->mmc), np, 1, NULL);
+	if (IS_ERR(base_dlyb))
+		return;
+
+	dlyb = devm_kzalloc(mmc_dev(host->mmc), sizeof(*dlyb), GFP_KERNEL);
+	if (!dlyb)
+		return;
+
+	dlyb->base = base_dlyb;
+	host->variant_priv = dlyb;
+	host->mmc_ops->execute_tuning = sdmmc_execute_tuning;
+}