| /* |
| * 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/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 |
| */ |
| static 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); |
| } |
| } |
| |
| 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 = { |
| .set_clock = sdhci_set_clock, |
| .get_max_clock = sdhci_pltfm_clk_get_max_clock, |
| .get_timeout_clock = sdhci_pltfm_clk_get_max_clock, |
| .platform_send_init_74_clocks = sdhci_bcm_kona_init_74_clocks, |
| .set_bus_width = sdhci_set_bus_width, |
| .reset = sdhci_reset, |
| .set_uhs_signaling = sdhci_set_uhs_signaling, |
| .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[] = { |
| { .compatible = "brcm,kona-sdhci"}, |
| { .compatible = "bcm,kona-sdhci"}, /* deprecated name */ |
| {} |
| }; |
| MODULE_DEVICE_TABLE(of, sdhci_bcm_kona_of_match); |
| |
| static int 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); |
| |
| ret = mmc_of_parse(host->mmc); |
| if (ret) |
| goto err_pltfm_free; |
| |
| if (!host->mmc->f_max) { |
| dev_err(&pdev->dev, "Missing max-freq for SDHCI cfg\n"); |
| ret = -ENXIO; |
| goto err_pltfm_free; |
| } |
| |
| /* Get and enable the core clock */ |
| pltfm_priv->clk = devm_clk_get(dev, NULL); |
| if (IS_ERR(pltfm_priv->clk)) { |
| dev_err(dev, "Failed to get core clock\n"); |
| ret = PTR_ERR(pltfm_priv->clk); |
| goto err_pltfm_free; |
| } |
| |
| if (clk_set_rate(pltfm_priv->clk, host->mmc->f_max) != 0) { |
| dev_err(dev, "Failed to set rate core clock\n"); |
| goto err_pltfm_free; |
| } |
| |
| if (clk_prepare_enable(pltfm_priv->clk) != 0) { |
| dev_err(dev, "Failed to enable core clock\n"); |
| goto err_pltfm_free; |
| } |
| |
| dev_dbg(dev, "non-removable=%c\n", |
| mmc_card_is_removable(host->mmc) ? 'N' : 'Y'); |
| 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 (!mmc_card_is_removable(host->mmc)) |
| 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_clk_disable; |
| |
| 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 (!mmc_card_is_removable(host->mmc)) { |
| 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_clk_disable: |
| clk_disable_unprepare(pltfm_priv->clk); |
| |
| err_pltfm_free: |
| sdhci_pltfm_free(pdev); |
| |
| dev_err(dev, "Probing of sdhci-pltfm failed: %d\n", ret); |
| return ret; |
| } |
| |
| static struct platform_driver sdhci_bcm_kona_driver = { |
| .driver = { |
| .name = "sdhci-kona", |
| .pm = SDHCI_PLTFM_PMOPS, |
| .of_match_table = sdhci_bcm_kona_of_match, |
| }, |
| .probe = sdhci_bcm_kona_probe, |
| .remove = sdhci_pltfm_unregister, |
| }; |
| module_platform_driver(sdhci_bcm_kona_driver); |
| |
| MODULE_DESCRIPTION("SDHCI driver for Broadcom Kona platform"); |
| MODULE_AUTHOR("Broadcom"); |
| MODULE_LICENSE("GPL v2"); |