diff options
Diffstat (limited to 'drivers/mmc/host/sdhci-iproc.c')
| -rw-r--r-- | drivers/mmc/host/sdhci-iproc.c | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-iproc.c b/drivers/mmc/host/sdhci-iproc.c new file mode 100644 index 000000000..f903ab96a --- /dev/null +++ b/drivers/mmc/host/sdhci-iproc.c @@ -0,0 +1,334 @@ +/* + * Copyright (C) 2014 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. + */ + +/* + * iProc SDHCI platform driver + */ + +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/mmc/host.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include "sdhci-pltfm.h" + +struct sdhci_iproc_data { + const struct sdhci_pltfm_data *pdata; + u32 caps; + u32 caps1; + u32 mmc_caps; +}; + +struct sdhci_iproc_host { + const struct sdhci_iproc_data *data; + u32 shadow_cmd; + u32 shadow_blk; + bool is_cmd_shadowed; + bool is_blk_shadowed; +}; + +#define REG_OFFSET_IN_BITS(reg) ((reg) << 3 & 0x18) + +static inline u32 sdhci_iproc_readl(struct sdhci_host *host, int reg) +{ + u32 val = readl(host->ioaddr + reg); + + pr_debug("%s: readl [0x%02x] 0x%08x\n", + mmc_hostname(host->mmc), reg, val); + return val; +} + +static u16 sdhci_iproc_readw(struct sdhci_host *host, int reg) +{ + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_iproc_host *iproc_host = sdhci_pltfm_priv(pltfm_host); + u32 val; + u16 word; + + if ((reg == SDHCI_TRANSFER_MODE) && iproc_host->is_cmd_shadowed) { + /* Get the saved transfer mode */ + val = iproc_host->shadow_cmd; + } else if ((reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) && + iproc_host->is_blk_shadowed) { + /* Get the saved block info */ + val = iproc_host->shadow_blk; + } else { + val = sdhci_iproc_readl(host, (reg & ~3)); + } + word = val >> REG_OFFSET_IN_BITS(reg) & 0xffff; + return word; +} + +static u8 sdhci_iproc_readb(struct sdhci_host *host, int reg) +{ + u32 val = sdhci_iproc_readl(host, (reg & ~3)); + u8 byte = val >> REG_OFFSET_IN_BITS(reg) & 0xff; + return byte; +} + +static inline void sdhci_iproc_writel(struct sdhci_host *host, u32 val, int reg) +{ + pr_debug("%s: writel [0x%02x] 0x%08x\n", + mmc_hostname(host->mmc), reg, val); + + writel(val, host->ioaddr + reg); + + if (host->clock <= 400000) { + /* Round up to micro-second four SD clock delay */ + if (host->clock) + udelay((4 * 1000000 + host->clock - 1) / host->clock); + else + udelay(10); + } +} + +/* + * The Arasan has a bugette whereby it may lose the content of successive + * writes to the same register that are within two SD-card clock cycles of + * each other (a clock domain crossing problem). The data + * register does not have this problem, which is just as well - otherwise we'd + * have to nobble the DMA engine too. + * + * This wouldn't be a problem with the code except that we can only write the + * controller with 32-bit writes. So two different 16-bit registers are + * written back to back creates the problem. + * + * In reality, this only happens when SDHCI_BLOCK_SIZE and SDHCI_BLOCK_COUNT + * are written followed by SDHCI_TRANSFER_MODE and SDHCI_COMMAND. + * The BLOCK_SIZE and BLOCK_COUNT are meaningless until a command issued so + * the work around can be further optimized. We can keep shadow values of + * BLOCK_SIZE, BLOCK_COUNT, and TRANSFER_MODE until a COMMAND is issued. + * Then, write the BLOCK_SIZE+BLOCK_COUNT in a single 32-bit write followed + * by the TRANSFER+COMMAND in another 32-bit write. + */ +static void sdhci_iproc_writew(struct sdhci_host *host, u16 val, int reg) +{ + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_iproc_host *iproc_host = sdhci_pltfm_priv(pltfm_host); + u32 word_shift = REG_OFFSET_IN_BITS(reg); + u32 mask = 0xffff << word_shift; + u32 oldval, newval; + + if (reg == SDHCI_COMMAND) { + /* Write the block now as we are issuing a command */ + if (iproc_host->is_blk_shadowed) { + sdhci_iproc_writel(host, iproc_host->shadow_blk, + SDHCI_BLOCK_SIZE); + iproc_host->is_blk_shadowed = false; + } + oldval = iproc_host->shadow_cmd; + iproc_host->is_cmd_shadowed = false; + } else if ((reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) && + iproc_host->is_blk_shadowed) { + /* Block size and count are stored in shadow reg */ + oldval = iproc_host->shadow_blk; + } else { + /* Read reg, all other registers are not shadowed */ + oldval = sdhci_iproc_readl(host, (reg & ~3)); + } + newval = (oldval & ~mask) | (val << word_shift); + + if (reg == SDHCI_TRANSFER_MODE) { + /* Save the transfer mode until the command is issued */ + iproc_host->shadow_cmd = newval; + iproc_host->is_cmd_shadowed = true; + } else if (reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) { + /* Save the block info until the command is issued */ + iproc_host->shadow_blk = newval; + iproc_host->is_blk_shadowed = true; + } else { + /* Command or other regular 32-bit write */ + sdhci_iproc_writel(host, newval, reg & ~3); + } +} + +static void sdhci_iproc_writeb(struct sdhci_host *host, u8 val, int reg) +{ + u32 oldval = sdhci_iproc_readl(host, (reg & ~3)); + u32 byte_shift = REG_OFFSET_IN_BITS(reg); + u32 mask = 0xff << byte_shift; + u32 newval = (oldval & ~mask) | (val << byte_shift); + + sdhci_iproc_writel(host, newval, reg & ~3); +} + +static const struct sdhci_ops sdhci_iproc_ops = { + .set_clock = sdhci_set_clock, + .get_max_clock = sdhci_pltfm_clk_get_max_clock, + .set_bus_width = sdhci_set_bus_width, + .reset = sdhci_reset, + .set_uhs_signaling = sdhci_set_uhs_signaling, +}; + +static const struct sdhci_ops sdhci_iproc_32only_ops = { + .read_l = sdhci_iproc_readl, + .read_w = sdhci_iproc_readw, + .read_b = sdhci_iproc_readb, + .write_l = sdhci_iproc_writel, + .write_w = sdhci_iproc_writew, + .write_b = sdhci_iproc_writeb, + .set_clock = sdhci_set_clock, + .get_max_clock = sdhci_pltfm_clk_get_max_clock, + .set_bus_width = sdhci_set_bus_width, + .reset = sdhci_reset, + .set_uhs_signaling = sdhci_set_uhs_signaling, +}; + +static const struct sdhci_pltfm_data sdhci_iproc_cygnus_pltfm_data = { + .quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK | + SDHCI_QUIRK_NO_HISPD_BIT, + .quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN | SDHCI_QUIRK2_HOST_OFF_CARD_ON, + .ops = &sdhci_iproc_32only_ops, +}; + +static const struct sdhci_iproc_data iproc_cygnus_data = { + .pdata = &sdhci_iproc_cygnus_pltfm_data, + .caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT) + & SDHCI_MAX_BLOCK_MASK) | + SDHCI_CAN_VDD_330 | + SDHCI_CAN_VDD_180 | + SDHCI_CAN_DO_SUSPEND | + SDHCI_CAN_DO_HISPD | + SDHCI_CAN_DO_ADMA2 | + SDHCI_CAN_DO_SDMA, + .caps1 = SDHCI_DRIVER_TYPE_C | + SDHCI_DRIVER_TYPE_D | + SDHCI_SUPPORT_DDR50, + .mmc_caps = MMC_CAP_1_8V_DDR, +}; + +static const struct sdhci_pltfm_data sdhci_iproc_pltfm_data = { + .quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK | + SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12 | + SDHCI_QUIRK_NO_HISPD_BIT, + .quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN, + .ops = &sdhci_iproc_ops, +}; + +static const struct sdhci_iproc_data iproc_data = { + .pdata = &sdhci_iproc_pltfm_data, + .caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT) + & SDHCI_MAX_BLOCK_MASK) | + SDHCI_CAN_VDD_330 | + SDHCI_CAN_VDD_180 | + SDHCI_CAN_DO_SUSPEND | + SDHCI_CAN_DO_HISPD | + SDHCI_CAN_DO_ADMA2 | + SDHCI_CAN_DO_SDMA, + .caps1 = SDHCI_DRIVER_TYPE_C | + SDHCI_DRIVER_TYPE_D | + SDHCI_SUPPORT_DDR50, +}; + +static const struct sdhci_pltfm_data sdhci_bcm2835_pltfm_data = { + .quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION | + SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK | + SDHCI_QUIRK_MISSING_CAPS | + SDHCI_QUIRK_NO_HISPD_BIT, + .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN, + .ops = &sdhci_iproc_32only_ops, +}; + +static const struct sdhci_iproc_data bcm2835_data = { + .pdata = &sdhci_bcm2835_pltfm_data, + .caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT) + & SDHCI_MAX_BLOCK_MASK) | + SDHCI_CAN_VDD_330 | + SDHCI_CAN_DO_HISPD, + .caps1 = SDHCI_DRIVER_TYPE_A | + SDHCI_DRIVER_TYPE_C, + .mmc_caps = 0x00000000, +}; + +static const struct of_device_id sdhci_iproc_of_match[] = { + { .compatible = "brcm,bcm2835-sdhci", .data = &bcm2835_data }, + { .compatible = "brcm,sdhci-iproc-cygnus", .data = &iproc_cygnus_data}, + { .compatible = "brcm,sdhci-iproc", .data = &iproc_data }, + { } +}; +MODULE_DEVICE_TABLE(of, sdhci_iproc_of_match); + +static int sdhci_iproc_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + const struct sdhci_iproc_data *iproc_data; + struct sdhci_host *host; + struct sdhci_iproc_host *iproc_host; + struct sdhci_pltfm_host *pltfm_host; + int ret; + + match = of_match_device(sdhci_iproc_of_match, &pdev->dev); + if (!match) + return -EINVAL; + iproc_data = match->data; + + host = sdhci_pltfm_init(pdev, iproc_data->pdata, sizeof(*iproc_host)); + if (IS_ERR(host)) + return PTR_ERR(host); + + pltfm_host = sdhci_priv(host); + iproc_host = sdhci_pltfm_priv(pltfm_host); + + iproc_host->data = iproc_data; + + ret = mmc_of_parse(host->mmc); + if (ret) + goto err; + + sdhci_get_of_property(pdev); + + host->mmc->caps |= iproc_host->data->mmc_caps; + + pltfm_host->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pltfm_host->clk)) { + ret = PTR_ERR(pltfm_host->clk); + goto err; + } + ret = clk_prepare_enable(pltfm_host->clk); + if (ret) { + dev_err(&pdev->dev, "failed to enable host clk\n"); + goto err; + } + + if (iproc_host->data->pdata->quirks & SDHCI_QUIRK_MISSING_CAPS) { + host->caps = iproc_host->data->caps; + host->caps1 = iproc_host->data->caps1; + } + + ret = sdhci_add_host(host); + if (ret) + goto err_clk; + + return 0; + +err_clk: + clk_disable_unprepare(pltfm_host->clk); +err: + sdhci_pltfm_free(pdev); + return ret; +} + +static struct platform_driver sdhci_iproc_driver = { + .driver = { + .name = "sdhci-iproc", + .of_match_table = sdhci_iproc_of_match, + .pm = &sdhci_pltfm_pmops, + }, + .probe = sdhci_iproc_probe, + .remove = sdhci_pltfm_unregister, +}; +module_platform_driver(sdhci_iproc_driver); + +MODULE_AUTHOR("Broadcom"); +MODULE_DESCRIPTION("IPROC SDHCI driver"); +MODULE_LICENSE("GPL v2"); |