[PATCH V7 8/9] mmc: sdhci-sprd: Add Spreadtrum's initial host controller

From: Chunyan Zhang
Date: Wed Aug 29 2018 - 03:03:53 EST


From: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>

This patch adds the initial support of Secure Digital Host Controller
Interface compliant controller found in some latest Spreadtrum chipsets.
This patch has been tested on the version of SPRD-R11 controller.

R11 is a variant based on SD v4.0 specification.

With this driver, R11 mmc can be initialized, can be mounted, read and
written.

Original-by: Billows Wu <billows.wu@xxxxxxxxxx>
Signed-off-by: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>
---
drivers/mmc/host/Kconfig | 13 ++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-sprd.c | 498 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 512 insertions(+)
create mode 100644 drivers/mmc/host/sdhci-sprd.c

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index d09feb6..cf984f0 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -593,6 +593,19 @@ config MMC_SDRICOH_CS
To compile this driver as a module, choose M here: the
module will be called sdricoh_cs.

+config MMC_SDHCI_SPRD
+ tristate "Spreadtrum SDIO host Controller"
+ depends on ARCH_SPRD
+ depends on MMC_SDHCI_PLTFM
+ select MMC_SDHCI_IO_ACCESSORS
+ help
+ This selects the SDIO Host Controller in Spreadtrum
+ SoCs, this driver supports R11(IP version: R11P0).
+
+ If you have a controller with this interface, say Y or M here.
+
+ If unsure, say N.
+
config MMC_TMIO_CORE
tristate

diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index a835d1a..5363d06 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -92,6 +92,7 @@ obj-$(CONFIG_MMC_SDHCI_ST) += sdhci-st.o
obj-$(CONFIG_MMC_SDHCI_MICROCHIP_PIC32) += sdhci-pic32.o
obj-$(CONFIG_MMC_SDHCI_BRCMSTB) += sdhci-brcmstb.o
obj-$(CONFIG_MMC_SDHCI_OMAP) += sdhci-omap.o
+obj-$(CONFIG_MMC_SDHCI_SPRD) += sdhci-sprd.o
obj-$(CONFIG_MMC_CQHCI) += cqhci.o

ifeq ($(CONFIG_CB710_DEBUG),y)
diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c
new file mode 100644
index 0000000..decd8cd
--- /dev/null
+++ b/drivers/mmc/host/sdhci-sprd.c
@@ -0,0 +1,498 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Secure Digital Host Controller
+//
+// Copyright (C) 2018 Spreadtrum, Inc.
+// Author: Chunyan Zhang <chunyan.zhang@xxxxxxxxxxxxxx>
+
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/highmem.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#include "sdhci-pltfm.h"
+
+/* SDHCI_ARGUMENT2 register high 16bit */
+#define SDHCI_SPRD_ARG2_STUFF GENMASK(31, 16)
+
+#define SDHCI_SPRD_REG_32_DLL_DLY_OFFSET 0x208
+#define SDHCIBSPRD_IT_WR_DLY_INV BIT(5)
+#define SDHCI_SPRD_BIT_CMD_DLY_INV BIT(13)
+#define SDHCI_SPRD_BIT_POSRD_DLY_INV BIT(21)
+#define SDHCI_SPRD_BIT_NEGRD_DLY_INV BIT(29)
+
+#define SDHCI_SPRD_REG_32_BUSY_POSI 0x250
+#define SDHCI_SPRD_BIT_OUTR_CLK_AUTO_EN BIT(25)
+#define SDHCI_SPRD_BIT_INNR_CLK_AUTO_EN BIT(24)
+
+#define SDHCI_SPRD_REG_DEBOUNCE 0x28C
+#define SDHCI_SPRD_BIT_DLL_BAK BIT(0)
+#define SDHCI_SPRD_BIT_DLL_VAL BIT(1)
+
+#define SDHCI_SPRD_INT_SIGNAL_MASK 0x1B7F410B
+
+/* SDHCI_HOST_CONTROL2 */
+#define SDHCI_SPRD_CTRL_HS200 0x0005
+#define SDHCI_SPRD_CTRL_HS400 0x0006
+
+/*
+ * According to the standard specification, BIT(3) of SDHCI_SOFTWARE_RESET is
+ * reserved, and only used on Spreadtrum's design, the hardware cannot work
+ * if this bit is cleared.
+ * 1 : normal work
+ * 0 : hardware reset
+ */
+#define SDHCI_HW_RESET_CARD BIT(3)
+
+#define SDHCI_SPRD_MAX_CUR 0xFFFFFF
+#define SDHCI_SPRD_CLK_MAX_DIV 1023
+
+#define SDHCI_SPRD_CLK_DEF_RATE 26000000
+
+struct sdhci_sprd_host {
+ u32 version;
+ struct clk *clk_sdio;
+ struct clk *clk_enable;
+ u32 base_rate;
+ int flags; /* backup of host attribute */
+};
+
+#define TO_SPRD_HOST(host) sdhci_pltfm_priv(sdhci_priv(host))
+
+static void sdhci_sprd_init_config(struct sdhci_host *host)
+{
+ u16 val;
+
+ /* set dll backup mode */
+ val = sdhci_readl(host, SDHCI_SPRD_REG_DEBOUNCE);
+ val |= SDHCI_SPRD_BIT_DLL_BAK | SDHCI_SPRD_BIT_DLL_VAL;
+ sdhci_writel(host, val, SDHCI_SPRD_REG_DEBOUNCE);
+}
+
+static inline u32 sdhci_sprd_readl(struct sdhci_host *host, int reg)
+{
+ if (unlikely(reg == SDHCI_MAX_CURRENT))
+ return SDHCI_SPRD_MAX_CUR;
+
+ return readl_relaxed(host->ioaddr + reg);
+}
+
+static inline void sdhci_sprd_writel(struct sdhci_host *host, u32 val, int reg)
+{
+ /* SDHCI_MAX_CURRENT is reserved on Spreadtrum's platform */
+ if (unlikely(reg == SDHCI_MAX_CURRENT))
+ return;
+
+ if (unlikely(reg == SDHCI_SIGNAL_ENABLE || reg == SDHCI_INT_ENABLE))
+ val = val & SDHCI_SPRD_INT_SIGNAL_MASK;
+
+ writel_relaxed(val, host->ioaddr + reg);
+}
+
+static inline void sdhci_sprd_writew(struct sdhci_host *host, u16 val, int reg)
+{
+ /* SDHCI_BLOCK_COUNT is Read Only on Spreadtrum's platform */
+ if (unlikely(reg == SDHCI_BLOCK_COUNT))
+ return;
+
+ writew_relaxed(val, host->ioaddr + reg);
+}
+
+static inline void sdhci_sprd_writeb(struct sdhci_host *host, u8 val, int reg)
+{
+ /*
+ * Since BIT(3) of SDHCI_SOFTWARE_RESET is reserved according to the
+ * standard specification, sdhci_reset() write this register directly
+ * without checking other reserved bits, that will clear BIT(3) which
+ * is defined as hardware reset on Spreadtrum's platform and clearing
+ * it by mistake will lead the card not work. So here we need to work
+ * around it.
+ */
+ if (unlikely(reg == SDHCI_SOFTWARE_RESET)) {
+ if (readb_relaxed(host->ioaddr + reg) & SDHCI_HW_RESET_CARD)
+ val |= SDHCI_HW_RESET_CARD;
+ }
+
+ writeb_relaxed(val, host->ioaddr + reg);
+}
+
+static inline void sdhci_sprd_sd_clk_off(struct sdhci_host *host)
+{
+ u16 ctrl = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+
+ ctrl &= ~SDHCI_CLOCK_CARD_EN;
+ sdhci_writew(host, ctrl, SDHCI_CLOCK_CONTROL);
+}
+
+static inline void
+sdhci_sprd_set_dll_invert(struct sdhci_host *host, u32 mask, bool en)
+{
+ u32 dll_dly_offset;
+
+ dll_dly_offset = sdhci_readl(host, SDHCI_SPRD_REG_32_DLL_DLY_OFFSET);
+ if (en)
+ dll_dly_offset |= mask;
+ else
+ dll_dly_offset &= ~mask;
+ sdhci_writel(host, dll_dly_offset, SDHCI_SPRD_REG_32_DLL_DLY_OFFSET);
+}
+
+static inline u32 sdhci_sprd_calc_div(u32 base_clk, u32 clk)
+{
+ u32 div;
+
+ /* select 2x clock source */
+ if (base_clk <= clk * 2)
+ return 0;
+
+ div = (u32) (base_clk / (clk * 2));
+
+ if ((base_clk / div) > (clk * 2))
+ div++;
+
+ if (div > SDHCI_SPRD_CLK_MAX_DIV)
+ div = SDHCI_SPRD_CLK_MAX_DIV;
+
+ if (div % 2)
+ div = (div + 1) / 2;
+ else
+ div = div / 2;
+
+ return div;
+}
+
+static inline void _sdhci_sprd_set_clock(struct sdhci_host *host,
+ unsigned int clk)
+{
+ struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
+ u32 div, val, mask;
+
+ div = sdhci_sprd_calc_div(sprd_host->base_rate, clk);
+
+ clk |= ((div & 0x300) >> 2) | ((div & 0xFF) << 8);
+ sdhci_enable_clk(host, clk);
+
+ /* enable auto gate sdhc_enable_auto_gate */
+ val = sdhci_readl(host, SDHCI_SPRD_REG_32_BUSY_POSI);
+ mask = SDHCI_SPRD_BIT_OUTR_CLK_AUTO_EN |
+ SDHCI_SPRD_BIT_INNR_CLK_AUTO_EN;
+ if (mask != (val & mask)) {
+ val |= mask;
+ sdhci_writel(host, val, SDHCI_SPRD_REG_32_BUSY_POSI);
+ }
+}
+
+static void sdhci_sprd_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+ bool en = false;
+
+ if (clock == 0) {
+ sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
+ } else if (clock != host->clock) {
+ sdhci_sprd_sd_clk_off(host);
+ _sdhci_sprd_set_clock(host, clock);
+
+ if (clock <= 400000)
+ en = true;
+ sdhci_sprd_set_dll_invert(host, SDHCI_SPRD_BIT_CMD_DLY_INV |
+ SDHCI_SPRD_BIT_POSRD_DLY_INV, en);
+ } else {
+ _sdhci_sprd_set_clock(host, clock);
+ }
+}
+
+static unsigned int sdhci_sprd_get_max_clock(struct sdhci_host *host)
+{
+ struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
+
+ return clk_round_rate(sprd_host->clk_sdio, ULONG_MAX);
+}
+
+static unsigned int sdhci_sprd_get_min_clock(struct sdhci_host *host)
+{
+ return 400000;
+}
+
+static void sdhci_sprd_set_uhs_signaling(struct sdhci_host *host,
+ unsigned int timing)
+{
+ u16 ctrl_2;
+
+ if (timing == host->timing)
+ return;
+
+ ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
+ /* Select Bus Speed Mode for host */
+ ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
+ switch (timing) {
+ case MMC_TIMING_UHS_SDR12:
+ ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
+ break;
+ case MMC_TIMING_MMC_HS:
+ case MMC_TIMING_SD_HS:
+ case MMC_TIMING_UHS_SDR25:
+ ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
+ break;
+ case MMC_TIMING_UHS_SDR50:
+ ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
+ break;
+ case MMC_TIMING_UHS_SDR104:
+ ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
+ break;
+ case MMC_TIMING_UHS_DDR50:
+ case MMC_TIMING_MMC_DDR52:
+ ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
+ break;
+ case MMC_TIMING_MMC_HS200:
+ ctrl_2 |= SDHCI_SPRD_CTRL_HS200;
+ break;
+ case MMC_TIMING_MMC_HS400:
+ ctrl_2 |= SDHCI_SPRD_CTRL_HS400;
+ break;
+ default:
+ break;
+ }
+
+ sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
+}
+
+static void sdhci_sprd_hw_reset(struct sdhci_host *host)
+{
+ int val;
+
+ /*
+ * Note: don't use sdhci_writeb() API here since it is redirected to
+ * sdhci_sprd_writeb() in which we have a workaround for
+ * SDHCI_SOFTWARE_RESET which would make bit SDHCI_HW_RESET_CARD can
+ * not be cleared.
+ */
+ val = readb_relaxed(host->ioaddr + SDHCI_SOFTWARE_RESET);
+ val &= ~SDHCI_HW_RESET_CARD;
+ writeb_relaxed(val, host->ioaddr + SDHCI_SOFTWARE_RESET);
+ /* wait for 10 us */
+ usleep_range(10, 20);
+
+ val |= SDHCI_HW_RESET_CARD;
+ writeb_relaxed(val, host->ioaddr + SDHCI_SOFTWARE_RESET);
+ usleep_range(300, 500);
+}
+
+static struct sdhci_ops sdhci_sprd_ops = {
+ .read_l = sdhci_sprd_readl,
+ .write_l = sdhci_sprd_writel,
+ .write_b = sdhci_sprd_writeb,
+ .set_clock = sdhci_sprd_set_clock,
+ .get_max_clock = sdhci_sprd_get_max_clock,
+ .get_min_clock = sdhci_sprd_get_min_clock,
+ .set_bus_width = sdhci_set_bus_width,
+ .reset = sdhci_reset,
+ .set_uhs_signaling = sdhci_sprd_set_uhs_signaling,
+ .hw_reset = sdhci_sprd_hw_reset,
+};
+
+static void sdhci_sprd_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct sdhci_host *host = mmc_priv(mmc);
+ struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
+
+ host->flags = sprd_host->flags;
+
+ /*
+ * From version 4.10 onward, ARGUMENT2 register is also as 32-bit
+ * block count register which doesn't support stuff bits of
+ * CMD23 argument on Spreadtrum's sd host controller.
+ */
+ if (host->version >= SDHCI_SPEC_410 &&
+ mrq->sbc && (mrq->sbc->arg & SDHCI_SPRD_ARG2_STUFF) &&
+ (host->flags & SDHCI_AUTO_CMD23))
+ host->flags &= ~SDHCI_AUTO_CMD23;
+
+ sdhci_request(mmc, mrq);
+}
+
+static const struct sdhci_pltfm_data sdhci_sprd_pdata = {
+ .quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK,
+ .quirks2 = SDHCI_QUIRK2_BROKEN_HS200 |
+ SDHCI_QUIRK2_USE_32BIT_BLK_CNT,
+ .ops = &sdhci_sprd_ops,
+};
+
+static int sdhci_sprd_probe(struct platform_device *pdev)
+{
+ struct sdhci_host *host;
+ struct sdhci_sprd_host *sprd_host;
+ struct clk *clk;
+ int ret = 0;
+
+ host = sdhci_pltfm_init(pdev, &sdhci_sprd_pdata, sizeof(*sprd_host));
+ if (IS_ERR(host))
+ return PTR_ERR(host);
+
+ host->dma_mask = DMA_BIT_MASK(64);
+ pdev->dev.dma_mask = &host->dma_mask;
+ host->mmc_host_ops.request = sdhci_sprd_request;
+
+ host->mmc->caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
+ MMC_CAP_ERASE | MMC_CAP_CMD23;
+ ret = mmc_of_parse(host->mmc);
+ if (ret)
+ goto pltfm_free;
+
+ sprd_host = TO_SPRD_HOST(host);
+
+ clk = devm_clk_get(&pdev->dev, "sdio");
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ goto pltfm_free;
+ }
+ sprd_host->clk_sdio = clk;
+ sprd_host->base_rate = clk_get_rate(sprd_host->clk_sdio);
+ if (!sprd_host->base_rate)
+ sprd_host->base_rate = SDHCI_SPRD_CLK_DEF_RATE;
+
+ clk = devm_clk_get(&pdev->dev, "enable");
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ goto pltfm_free;
+ }
+ sprd_host->clk_enable = clk;
+
+ ret = clk_prepare_enable(sprd_host->clk_sdio);
+ if (ret)
+ goto pltfm_free;
+
+ clk_prepare_enable(sprd_host->clk_enable);
+ if (ret)
+ goto clk_disable;
+
+ sdhci_sprd_init_config(host);
+ host->version = sdhci_readw(host, SDHCI_HOST_VERSION);
+ sprd_host->version = ((host->version & SDHCI_VENDOR_VER_MASK) >>
+ SDHCI_VENDOR_VER_SHIFT);
+
+ pm_runtime_get_noresume(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_suspend_ignore_children(&pdev->dev, 1);
+
+ sdhci_enable_v4_mode(host);
+
+ ret = sdhci_setup_host(host);
+ if (ret)
+ goto pm_runtime_disable;
+
+ sprd_host->flags = host->flags;
+
+ ret = __sdhci_add_host(host);
+ if (ret)
+ goto err_cleanup_host;
+
+ pm_runtime_mark_last_busy(&pdev->dev);
+ pm_runtime_put_autosuspend(&pdev->dev);
+
+ return 0;
+
+err_cleanup_host:
+ sdhci_cleanup_host(host);
+
+pm_runtime_disable:
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+
+ clk_disable_unprepare(sprd_host->clk_enable);
+
+clk_disable:
+ clk_disable_unprepare(sprd_host->clk_sdio);
+
+pltfm_free:
+ sdhci_pltfm_free(pdev);
+ return ret;
+}
+
+static int sdhci_sprd_remove(struct platform_device *pdev)
+{
+ struct sdhci_host *host = platform_get_drvdata(pdev);
+ struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
+ struct mmc_host *mmc = host->mmc;
+
+ mmc_remove_host(mmc);
+ clk_disable_unprepare(sprd_host->clk_sdio);
+ clk_disable_unprepare(sprd_host->clk_enable);
+
+ mmc_free_host(mmc);
+
+ return 0;
+}
+
+static const struct of_device_id sdhci_sprd_of_match[] = {
+ { .compatible = "sprd,sdhci-r11", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, sdhci_sprd_of_match);
+
+#ifdef CONFIG_PM
+static int sdhci_sprd_runtime_suspend(struct device *dev)
+{
+ struct sdhci_host *host = dev_get_drvdata(dev);
+ struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
+
+ sdhci_runtime_suspend_host(host);
+
+ clk_disable_unprepare(sprd_host->clk_sdio);
+ clk_disable_unprepare(sprd_host->clk_enable);
+
+ return 0;
+}
+
+static int sdhci_sprd_runtime_resume(struct device *dev)
+{
+ struct sdhci_host *host = dev_get_drvdata(dev);
+ struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
+ int ret;
+
+ ret = clk_prepare_enable(sprd_host->clk_enable);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(sprd_host->clk_sdio);
+ if (ret) {
+ clk_disable_unprepare(sprd_host->clk_enable);
+ return ret;
+ }
+
+ sdhci_runtime_resume_host(host);
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops sdhci_sprd_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(sdhci_sprd_runtime_suspend,
+ sdhci_sprd_runtime_resume, NULL)
+};
+
+static struct platform_driver sdhci_sprd_driver = {
+ .probe = sdhci_sprd_probe,
+ .remove = sdhci_sprd_remove,
+ .driver = {
+ .name = "sdhci_sprd_r11",
+ .of_match_table = of_match_ptr(sdhci_sprd_of_match),
+ .pm = &sdhci_sprd_pm_ops,
+ },
+};
+module_platform_driver(sdhci_sprd_driver);
+
+MODULE_DESCRIPTION("Spreadtrum sdio host controller r11 driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:sdhci-sprd-r11");
--
2.7.4