mmc: bcm281xx SDHCI driver

Add SDHCI driver for the Broadcom 281xx SoCs.

Still missing:
 - power managemement

Signed-off-by: Christian Daudt <csd@broadcom.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Ball <cjb@laptop.org>

diff --git a/arch/arm/configs/bcm_defconfig b/arch/arm/configs/bcm_defconfig
index e3bf2d65618e3c05dfd0bc582756dc317ec36b8c..65edf6d47215b23fdad0ef259b7b69db709dd565 100644 (file)
--- a/arch/arm/configs/bcm_defconfig
+++ b/arch/arm/configs/bcm_defconfig
@@ -78,6 +78,13 @@ CONFIG_BACKLIGHT_LCD_SUPPORT=y
 CONFIG_LCD_CLASS_DEVICE=y
 CONFIG_BACKLIGHT_CLASS_DEVICE=y
 # CONFIG_USB_SUPPORT is not set
+CONFIG_MMC=y
+CONFIG_MMC_UNSAFE_RESUME=y
+CONFIG_MMC_BLOCK_MINORS=32
+CONFIG_MMC_TEST=y
+CONFIG_MMC_SDHCI=y
+CONFIG_MMC_SDHCI_PLTFM=y
+CONFIG_MMC_SDHCI_BCM_KONA=y
 CONFIG_NEW_LEDS=y
 CONFIG_LEDS_CLASS=y
 CONFIG_LEDS_TRIGGERS=y

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 1be228998c814c2199bffd30c434a9bf0b79ac42..8a4c066787d7ca3acd4d38cb6be87c4588e19a05 100644 (file)
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -249,6 +249,17 @@ config MMC_SDHCI_S3C_DMA
 
          YMMV.
 
+config MMC_SDHCI_BCM_KONA
+       tristate "SDHCI support on Broadcom KONA platform"
+       depends on ARCH_BCM
+       select MMC_SDHCI_PLTFM
+       help
+         This selects the Broadcom Kona Secure Digital Host Controller
+         Interface(SDHCI) support.
+         This is used in Broadcom mobile SoCs.
+
+         If you have a controller with this interface, say Y or M here.
+
 config MMC_SDHCI_BCM2835
        tristate "SDHCI platform support for the BCM2835 SD/MMC Controller"
        depends on ARCH_BCM2835

diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 67718c1b79ceae37cf4bec87075ff977b9d913c8..d422e2167e19cc99b5a258c23daa1c22a86b5fa1 100644 (file)
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -61,6 +61,7 @@ obj-$(CONFIG_MMC_SDHCI_DOVE)          += sdhci-dove.o
 obj-$(CONFIG_MMC_SDHCI_TEGRA)          += sdhci-tegra.o
 obj-$(CONFIG_MMC_SDHCI_OF_ESDHC)       += sdhci-of-esdhc.o
 obj-$(CONFIG_MMC_SDHCI_OF_HLWD)                += sdhci-of-hlwd.o
+obj-$(CONFIG_MMC_SDHCI_BCM_KONA)       += sdhci-bcm-kona.o
 obj-$(CONFIG_MMC_SDHCI_BCM2835)                += sdhci-bcm2835.o
 
 ifeq ($(CONFIG_CB710_DEBUG),y)

diff --git a/drivers/mmc/host/sdhci-bcm-kona.c b/drivers/mmc/host/sdhci-bcm-kona.c
new file mode 100644 (file)
index 0000000..87175f9
--- /dev/null
+++ b/drivers/mmc/host/sdhci-bcm-kona.c
@@ -0,0 +1,348 @@
+/*
+ * Copyright (C) 2013 Broadcom Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/highmem.h>
+#include <linux/platform_device.h>
+#include <linux/mmc/host.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/clk.h>
+#include <linux/regulator/consumer.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/version.h>
+#include <linux/mmc/slot-gpio.h>
+
+#include "sdhci-pltfm.h"
+#include "sdhci.h"
+
+#define SDHCI_SOFT_RESET                       0x01000000
+#define KONA_SDHOST_CORECTRL                   0x8000
+#define KONA_SDHOST_CD_PINCTRL                 0x00000008
+#define KONA_SDHOST_STOP_HCLK                  0x00000004
+#define KONA_SDHOST_RESET                      0x00000002
+#define KONA_SDHOST_EN                         0x00000001
+
+#define KONA_SDHOST_CORESTAT                   0x8004
+#define KONA_SDHOST_WP                         0x00000002
+#define KONA_SDHOST_CD_SW                      0x00000001
+
+#define KONA_SDHOST_COREIMR                    0x8008
+#define KONA_SDHOST_IP                         0x00000001
+
+#define KONA_SDHOST_COREISR                    0x800C
+#define KONA_SDHOST_COREIMSR                   0x8010
+#define KONA_SDHOST_COREDBG1                   0x8014
+#define KONA_SDHOST_COREGPO_MASK               0x8018
+
+#define SD_DETECT_GPIO_DEBOUNCE_128MS          128
+
+#define KONA_MMC_AUTOSUSPEND_DELAY             (50)
+
+struct sdhci_bcm_kona_dev {
+       struct mutex    write_lock; /* protect back to back writes */
+};
+
+
+static int sdhci_bcm_kona_sd_reset(struct sdhci_host *host)
+{
+       unsigned int val;
+       unsigned long timeout;
+
+       /* This timeout should be sufficent for core to reset */
+       timeout = jiffies + msecs_to_jiffies(100);
+
+       /* reset the host using the top level reset */
+       val = sdhci_readl(host, KONA_SDHOST_CORECTRL);
+       val |= KONA_SDHOST_RESET;
+       sdhci_writel(host, val, KONA_SDHOST_CORECTRL);
+
+       while (!(sdhci_readl(host, KONA_SDHOST_CORECTRL) & KONA_SDHOST_RESET)) {
+               if (time_is_before_jiffies(timeout)) {
+                       pr_err("Error: sd host is stuck in reset!!!\n");
+                       return -EFAULT;
+               }
+       }
+
+       /* bring the host out of reset */
+       val = sdhci_readl(host, KONA_SDHOST_CORECTRL);
+       val &= ~KONA_SDHOST_RESET;
+
+       /*
+        * Back-to-Back register write needs a delay of 1ms at bootup (min 10uS)
+        * Back-to-Back writes to same register needs delay when SD bus clock
+        * is very low w.r.t AHB clock, mainly during boot-time and during card
+        * insert-removal.
+        */
+       usleep_range(1000, 5000);
+       sdhci_writel(host, val, KONA_SDHOST_CORECTRL);
+
+       return 0;
+}
+
+static void sdhci_bcm_kona_sd_init(struct sdhci_host *host)
+{
+       unsigned int val;
+
+       /* enable the interrupt from the IP core */
+       val = sdhci_readl(host, KONA_SDHOST_COREIMR);
+       val |= KONA_SDHOST_IP;
+       sdhci_writel(host, val, KONA_SDHOST_COREIMR);
+
+       /* Enable the AHB clock gating module to the host */
+       val = sdhci_readl(host, KONA_SDHOST_CORECTRL);
+       val |= KONA_SDHOST_EN;
+
+       /*
+        * Back-to-Back register write needs a delay of 1ms at bootup (min 10uS)
+        * Back-to-Back writes to same register needs delay when SD bus clock
+        * is very low w.r.t AHB clock, mainly during boot-time and during card
+        * insert-removal.
+        */
+       usleep_range(1000, 5000);
+       sdhci_writel(host, val, KONA_SDHOST_CORECTRL);
+}
+
+/*
+ * Software emulation of the SD card insertion/removal. Set insert=1 for insert
+ * and insert=0 for removal. The card detection is done by GPIO. For Broadcom
+ * IP to function properly the bit 0 of CORESTAT register needs to be set/reset
+ * to generate the CD IRQ handled in sdhci.c which schedules card_tasklet.
+ */
+static int sdhci_bcm_kona_sd_card_emulate(struct sdhci_host *host, int insert)
+{
+       struct sdhci_pltfm_host *pltfm_priv = sdhci_priv(host);
+       struct sdhci_bcm_kona_dev *kona_dev = sdhci_pltfm_priv(pltfm_priv);
+       u32 val;
+
+       /*
+        * Back-to-Back register write needs a delay of min 10uS.
+        * Back-to-Back writes to same register needs delay when SD bus clock
+        * is very low w.r.t AHB clock, mainly during boot-time and during card
+        * insert-removal.
+        * We keep 20uS
+        */
+       mutex_lock(&kona_dev->write_lock);
+       udelay(20);
+       val = sdhci_readl(host, KONA_SDHOST_CORESTAT);
+
+       if (insert) {
+               int ret;
+
+               ret = mmc_gpio_get_ro(host->mmc);
+               if (ret >= 0)
+                       val = (val & ~KONA_SDHOST_WP) |
+                               ((ret) ? KONA_SDHOST_WP : 0);
+
+               val |= KONA_SDHOST_CD_SW;
+               sdhci_writel(host, val, KONA_SDHOST_CORESTAT);
+       } else {
+               val &= ~KONA_SDHOST_CD_SW;
+               sdhci_writel(host, val, KONA_SDHOST_CORESTAT);
+       }
+       mutex_unlock(&kona_dev->write_lock);
+
+       return 0;
+}
+
+/*
+ * SD card interrupt event callback
+ */
+void sdhci_bcm_kona_card_event(struct sdhci_host *host)
+{
+       if (mmc_gpio_get_cd(host->mmc) > 0) {
+               dev_dbg(mmc_dev(host->mmc),
+                       "card inserted\n");
+               sdhci_bcm_kona_sd_card_emulate(host, 1);
+       } else {
+               dev_dbg(mmc_dev(host->mmc),
+                       "card removed\n");
+               sdhci_bcm_kona_sd_card_emulate(host, 0);
+       }
+}
+
+/*
+ * Get the base clock. Use central clock source for now. Not sure if different
+ * clock speed to each dev is allowed
+ */
+static unsigned int sdhci_bcm_kona_get_max_clk(struct sdhci_host *host)
+{
+       struct sdhci_bcm_kona_dev *kona_dev;
+       struct sdhci_pltfm_host *pltfm_priv = sdhci_priv(host);
+       kona_dev = sdhci_pltfm_priv(pltfm_priv);
+
+       return host->mmc->f_max;
+}
+
+static unsigned int sdhci_bcm_kona_get_timeout_clock(struct sdhci_host *host)
+{
+       return sdhci_bcm_kona_get_max_clk(host);
+}
+
+static void sdhci_bcm_kona_init_74_clocks(struct sdhci_host *host,
+                               u8 power_mode)
+{
+       /*
+        *  JEDEC and SD spec specify supplying 74 continuous clocks to
+        * device after power up. With minimum bus (100KHz) that
+        * that translates to 740us
+        */
+       if (power_mode != MMC_POWER_OFF)
+               udelay(740);
+}
+
+static struct sdhci_ops sdhci_bcm_kona_ops = {
+       .get_max_clock = sdhci_bcm_kona_get_max_clk,
+       .get_timeout_clock = sdhci_bcm_kona_get_timeout_clock,
+       .platform_send_init_74_clocks = sdhci_bcm_kona_init_74_clocks,
+       .card_event = sdhci_bcm_kona_card_event,
+};
+
+static struct sdhci_pltfm_data sdhci_pltfm_data_kona = {
+       .ops    = &sdhci_bcm_kona_ops,
+       .quirks = SDHCI_QUIRK_NO_CARD_NO_RESET |
+               SDHCI_QUIRK_BROKEN_TIMEOUT_VAL | SDHCI_QUIRK_32BIT_DMA_ADDR |
+               SDHCI_QUIRK_32BIT_DMA_SIZE | SDHCI_QUIRK_32BIT_ADMA_SIZE |
+               SDHCI_QUIRK_FORCE_BLK_SZ_2048 |
+               SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
+};
+
+static const struct of_device_id sdhci_bcm_kona_of_match[] __initdata = {
+       { .compatible = "bcm,kona-sdhci"},
+       {}
+};
+MODULE_DEVICE_TABLE(of, sdhci_bcm_kona_of_match);
+
+static int __init sdhci_bcm_kona_probe(struct platform_device *pdev)
+{
+       struct sdhci_bcm_kona_dev *kona_dev = NULL;
+       struct sdhci_pltfm_host *pltfm_priv;
+       struct device *dev = &pdev->dev;
+       struct sdhci_host *host;
+       int ret;
+
+       ret = 0;
+
+       host = sdhci_pltfm_init(pdev, &sdhci_pltfm_data_kona,
+                       sizeof(*kona_dev));
+       if (IS_ERR(host))
+               return PTR_ERR(host);
+
+       dev_dbg(dev, "%s: inited. IOADDR=%p\n", __func__, host->ioaddr);
+
+       pltfm_priv = sdhci_priv(host);
+
+       kona_dev = sdhci_pltfm_priv(pltfm_priv);
+       mutex_init(&kona_dev->write_lock);
+
+       mmc_of_parse(host->mmc);
+
+       if (!host->mmc->f_max) {
+               dev_err(&pdev->dev, "Missing max-freq for SDHCI cfg\n");
+               ret = -ENXIO;
+               goto err_pltfm_free;
+       }
+
+       dev_dbg(dev, "non-removable=%c\n",
+               (host->mmc->caps & MMC_CAP_NONREMOVABLE) ? 'Y' : 'N');
+       dev_dbg(dev, "cd_gpio %c, wp_gpio %c\n",
+               (mmc_gpio_get_cd(host->mmc) != -ENOSYS) ? 'Y' : 'N',
+               (mmc_gpio_get_ro(host->mmc) != -ENOSYS) ? 'Y' : 'N');
+
+       if (host->mmc->caps | MMC_CAP_NONREMOVABLE)
+               host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
+
+       dev_dbg(dev, "is_8bit=%c\n",
+               (host->mmc->caps | MMC_CAP_8_BIT_DATA) ? 'Y' : 'N');
+
+       ret = sdhci_bcm_kona_sd_reset(host);
+       if (ret)
+               goto err_pltfm_free;
+
+       sdhci_bcm_kona_sd_init(host);
+
+       ret = sdhci_add_host(host);
+       if (ret) {
+               dev_err(dev, "Failed sdhci_add_host\n");
+               goto err_reset;
+       }
+
+       /* if device is eMMC, emulate card insert right here */
+       if (host->mmc->caps | MMC_CAP_NONREMOVABLE) {
+               ret = sdhci_bcm_kona_sd_card_emulate(host, 1);
+               if (ret) {
+                       dev_err(dev,
+                               "unable to emulate card insertion\n");
+                       goto err_remove_host;
+               }
+       }
+       /*
+        * Since the card detection GPIO interrupt is configured to be
+        * edge sensitive, check the initial GPIO value here, emulate
+        * only if the card is present
+        */
+       if (mmc_gpio_get_cd(host->mmc) > 0)
+               sdhci_bcm_kona_sd_card_emulate(host, 1);
+
+       dev_dbg(dev, "initialized properly\n");
+       return 0;
+
+err_remove_host:
+       sdhci_remove_host(host, 0);
+
+err_reset:
+       sdhci_bcm_kona_sd_reset(host);
+
+err_pltfm_free:
+       sdhci_pltfm_free(pdev);
+
+       dev_err(dev, "Probing of sdhci-pltfm failed: %d\n", ret);
+       return ret;
+}
+
+static int __exit sdhci_bcm_kona_remove(struct platform_device *pdev)
+{
+       struct sdhci_host *host = platform_get_drvdata(pdev);
+       int dead;
+       u32 scratch;
+
+       dead = 0;
+       scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
+       if (scratch == (u32)-1)
+               dead = 1;
+       sdhci_remove_host(host, dead);
+
+       sdhci_free_host(host);
+
+       return 0;
+}
+
+static struct platform_driver sdhci_bcm_kona_driver = {
+       .driver         = {
+               .name   = "sdhci-kona",
+               .owner  = THIS_MODULE,
+               .pm     = SDHCI_PLTFM_PMOPS,
+               .of_match_table = of_match_ptr(sdhci_bcm_kona_of_match),
+       },
+       .probe          = sdhci_bcm_kona_probe,
+       .remove         = __exit_p(sdhci_bcm_kona_remove),
+};
+module_platform_driver(sdhci_bcm_kona_driver);
+
+MODULE_DESCRIPTION("SDHCI driver for Broadcom Kona platform");
+MODULE_AUTHOR("Broadcom");
+MODULE_LICENSE("GPL v2");