diff options
-rw-r--r-- | MAINTAINERS | 7 | ||||
-rw-r--r-- | drivers/mmc/host/Kconfig | 25 | ||||
-rw-r--r-- | drivers/mmc/host/Makefile | 1 | ||||
-rw-r--r-- | drivers/mmc/host/sdhci-s3c.c | 425 |
4 files changed, 458 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index dc226e7..ba7ee2b 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5094,6 +5094,13 @@ L: sdhci-devel@lists.ossman.eu S: Maintained F: drivers/mmc/host/sdhci.* +SECURE DIGITAL HOST CONTROLLER INTERFACE (SDHCI) SAMSUNG DRIVER +P: Ben Dooks +M: ben-linux@fluff.org +L: sdhci-devel@lists.ossman.eu +S: Maintained +F: drivers/mmc/host/sdhci-s3c.c + SECURITY SUBSYSTEM P: James Morris M: jmorris@namei.org diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig index 40111a6..7609922 100644 --- a/drivers/mmc/host/Kconfig +++ b/drivers/mmc/host/Kconfig @@ -94,6 +94,31 @@ config MMC_SDHCI_PLTFM If unsure, say N. +config MMC_SDHCI_S3C + tristate "SDHCI support on Samsung S3C SoC" + depends on MMC_SDHCI && (PLAT_S3C24XX || PLAT_S3C64XX) + help + This selects the Secure Digital Host Controller Interface (SDHCI) + often referrered to as the HSMMC block in some of the Samsung S3C + range of SoC. + + Note, due to the problems with DMA, the DMA support is only + available with CONFIG_EXPERIMENTAL is selected. + + If you have a controller with this interface, say Y or M here. + + If unsure, say N. + +config MMC_SDHCI_S3C_DMA + bool "DMA support on S3C SDHCI" + depends on MMC_SDHCI_S3C && EXPERIMENTAL + help + Enable DMA support on the Samsung S3C SDHCI glue. The DMA + has proved to be problematic if the controller encounters + certain errors, and thus should be treated with care. + + YMMV. + config MMC_OMAP tristate "TI OMAP Multimedia Card Interface support" depends on ARCH_OMAP diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile index 79da397..e637f2f 100644 --- a/drivers/mmc/host/Makefile +++ b/drivers/mmc/host/Makefile @@ -15,6 +15,7 @@ obj-$(CONFIG_MMC_SDHCI_PCI) += sdhci-pci.o obj-$(CONFIG_MMC_RICOH_MMC) += ricoh_mmc.o obj-$(CONFIG_MMC_SDHCI_OF) += sdhci-of.o obj-$(CONFIG_MMC_SDHCI_PLTFM) += sdhci-pltfm.o +obj-$(CONFIG_MMC_SDHCI_S3C) += sdhci-s3c.o obj-$(CONFIG_MMC_WBSD) += wbsd.o obj-$(CONFIG_MMC_AU1X) += au1xmmc.o obj-$(CONFIG_MMC_OMAP) += omap.o diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c new file mode 100644 index 0000000..19246fe --- /dev/null +++ b/drivers/mmc/host/sdhci-s3c.c @@ -0,0 +1,425 @@ +/* linux/drivers/mmc/host/sdhci-s3c.c + * + * Copyright 2008 Openmoko Inc. + * Copyright 2008 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * http://armlinux.simtec.co.uk/ + * + * SDHCI (HSMMC) support for Samsung SoC + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/io.h> + +#include <linux/mmc/host.h> + +#include <plat/sdhci.h> +#include <plat/regs-sdhci.h> + +#include "sdhci.h" + +#define MAX_BUS_CLK (4) + +/** + * struct sdhci_s3c - S3C SDHCI instance + * @host: The SDHCI host created + * @pdev: The platform device we where created from. + * @ioarea: The resource created when we claimed the IO area. + * @pdata: The platform data for this controller. + * @cur_clk: The index of the current bus clock. + * @clk_io: The clock for the internal bus interface. + * @clk_bus: The clocks that are available for the SD/MMC bus clock. + */ +struct sdhci_s3c { + struct sdhci_host *host; + struct platform_device *pdev; + struct resource *ioarea; + struct s3c_sdhci_platdata *pdata; + unsigned int cur_clk; + + struct clk *clk_io; + struct clk *clk_bus[MAX_BUS_CLK]; +}; + +static inline struct sdhci_s3c *to_s3c(struct sdhci_host *host) +{ + return sdhci_priv(host); +} + +/** + * get_curclk - convert ctrl2 register to clock source number + * @ctrl2: Control2 register value. + */ +static u32 get_curclk(u32 ctrl2) +{ + ctrl2 &= S3C_SDHCI_CTRL2_SELBASECLK_MASK; + ctrl2 >>= S3C_SDHCI_CTRL2_SELBASECLK_SHIFT; + + return ctrl2; +} + +static void sdhci_s3c_check_sclk(struct sdhci_host *host) +{ + struct sdhci_s3c *ourhost = to_s3c(host); + u32 tmp = readl(host->ioaddr + S3C_SDHCI_CONTROL2); + + if (get_curclk(tmp) != ourhost->cur_clk) { + dev_dbg(&ourhost->pdev->dev, "restored ctrl2 clock setting\n"); + + tmp &= ~S3C_SDHCI_CTRL2_SELBASECLK_MASK; + tmp |= ourhost->cur_clk << S3C_SDHCI_CTRL2_SELBASECLK_SHIFT; + writel(tmp, host->ioaddr + 0x80); + } +} + +/** + * sdhci_s3c_get_max_clk - callback to get maximum clock frequency. + * @host: The SDHCI host instance. + * + * Callback to return the maximum clock rate acheivable by the controller. +*/ +static unsigned int sdhci_s3c_get_max_clk(struct sdhci_host *host) +{ + struct sdhci_s3c *ourhost = to_s3c(host); + struct clk *busclk; + unsigned int rate, max; + int clk; + + /* note, a reset will reset the clock source */ + + sdhci_s3c_check_sclk(host); + + for (max = 0, clk = 0; clk < MAX_BUS_CLK; clk++) { + busclk = ourhost->clk_bus[clk]; + if (!busclk) + continue; + + rate = clk_get_rate(busclk); + if (rate > max) + max = rate; + } + + return max; +} + +static unsigned int sdhci_s3c_get_timeout_clk(struct sdhci_host *host) +{ + return sdhci_s3c_get_max_clk(host) / 1000000; +} + +/** + * sdhci_s3c_consider_clock - consider one the bus clocks for current setting + * @ourhost: Our SDHCI instance. + * @src: The source clock index. + * @wanted: The clock frequency wanted. + */ +static unsigned int sdhci_s3c_consider_clock(struct sdhci_s3c *ourhost, + unsigned int src, + unsigned int wanted) +{ + unsigned long rate; + struct clk *clksrc = ourhost->clk_bus[src]; + int div; + + if (!clksrc) + return UINT_MAX; + + rate = clk_get_rate(clksrc); + + for (div = 1; div < 256; div *= 2) { + if ((rate / div) <= wanted) + break; + } + + dev_dbg(&ourhost->pdev->dev, "clk %d: rate %ld, want %d, got %ld\n", + src, rate, wanted, rate / div); + + return (wanted - (rate / div)); +} + +/** + * sdhci_s3c_set_clock - callback on clock change + * @host: The SDHCI host being changed + * @clock: The clock rate being requested. + * + * When the card's clock is going to be changed, look at the new frequency + * and find the best clock source to go with it. +*/ +static void sdhci_s3c_set_clock(struct sdhci_host *host, unsigned int clock) +{ + struct sdhci_s3c *ourhost = to_s3c(host); + unsigned int best = UINT_MAX; + unsigned int delta; + int best_src = 0; + int src; + u32 ctrl; + + /* don't bother if the clock is going off. */ + if (clock == 0) + return; + + for (src = 0; src < MAX_BUS_CLK; src++) { + delta = sdhci_s3c_consider_clock(ourhost, src, clock); + if (delta < best) { + best = delta; + best_src = src; + } + } + + dev_dbg(&ourhost->pdev->dev, + "selected source %d, clock %d, delta %d\n", + best_src, clock, best); + + /* select the new clock source */ + + if (ourhost->cur_clk != best_src) { + struct clk *clk = ourhost->clk_bus[best_src]; + + /* turn clock off to card before changing clock source */ + writew(0, host->ioaddr + SDHCI_CLOCK_CONTROL); + + ourhost->cur_clk = best_src; + host->max_clk = clk_get_rate(clk); + host->timeout_clk = sdhci_s3c_get_timeout_clk(host); + + ctrl = readl(host->ioaddr + S3C_SDHCI_CONTROL2); + ctrl &= ~S3C_SDHCI_CTRL2_SELBASECLK_MASK; + ctrl |= best_src << S3C_SDHCI_CTRL2_SELBASECLK_SHIFT; + writel(ctrl, host->ioaddr + S3C_SDHCI_CONTROL2); + } + + /* reconfigure the hardware for new clock rate */ + + { + struct mmc_ios ios; + + ios.clock = clock; + + if (ourhost->pdata->cfg_card) + (ourhost->pdata->cfg_card)(ourhost->pdev, host->ioaddr, + &ios, NULL); + } +} + +static struct sdhci_ops sdhci_s3c_ops = { + .get_max_clock = sdhci_s3c_get_max_clk, + .get_timeout_clock = sdhci_s3c_get_timeout_clk, + .set_clock = sdhci_s3c_set_clock, +}; + +static int __devinit sdhci_s3c_probe(struct platform_device *pdev) +{ + struct s3c_sdhci_platdata *pdata = pdev->dev.platform_data; + struct device *dev = &pdev->dev; + struct sdhci_host *host; + struct sdhci_s3c *sc; + struct resource *res; + int ret, irq, ptr, clks; + + if (!pdata) { + dev_err(dev, "no device data specified\n"); + return -ENOENT; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(dev, "no irq specified\n"); + return irq; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(dev, "no memory specified\n"); + return -ENOENT; + } + + host = sdhci_alloc_host(dev, sizeof(struct sdhci_s3c)); + if (IS_ERR(host)) { + dev_err(dev, "sdhci_alloc_host() failed\n"); + return PTR_ERR(host); + } + + sc = sdhci_priv(host); + + sc->host = host; + sc->pdev = pdev; + sc->pdata = pdata; + + platform_set_drvdata(pdev, host); + + sc->clk_io = clk_get(dev, "hsmmc"); + if (IS_ERR(sc->clk_io)) { + dev_err(dev, "failed to get io clock\n"); + ret = PTR_ERR(sc->clk_io); + goto err_io_clk; + } + + /* enable the local io clock and keep it running for the moment. */ + clk_enable(sc->clk_io); + + for (clks = 0, ptr = 0; ptr < MAX_BUS_CLK; ptr++) { + struct clk *clk; + char *name = pdata->clocks[ptr]; + + if (name == NULL) + continue; + + clk = clk_get(dev, name); + if (IS_ERR(clk)) { + dev_err(dev, "failed to get clock %s\n", name); + continue; + } + + clks++; + sc->clk_bus[ptr] = clk; + clk_enable(clk); + + dev_info(dev, "clock source %d: %s (%ld Hz)\n", + ptr, name, clk_get_rate(clk)); + } + + if (clks == 0) { + dev_err(dev, "failed to find any bus clocks\n"); + ret = -ENOENT; + goto err_no_busclks; + } + + sc->ioarea = request_mem_region(res->start, resource_size(res), + mmc_hostname(host->mmc)); + if (!sc->ioarea) { + dev_err(dev, "failed to reserve register area\n"); + ret = -ENXIO; + goto err_req_regs; + } + + host->ioaddr = ioremap_nocache(res->start, resource_size(res)); + if (!host->ioaddr) { + dev_err(dev, "failed to map registers\n"); + ret = -ENXIO; + goto err_req_regs; + } + + /* Ensure we have minimal gpio selected CMD/CLK/Detect */ + if (pdata->cfg_gpio) + pdata->cfg_gpio(pdev, pdata->max_width); + + host->hw_name = "samsung-hsmmc"; + host->ops = &sdhci_s3c_ops; + host->quirks = 0; + host->irq = irq; + + /* Setup quirks for the controller */ + + /* Currently with ADMA enabled we are getting some length + * interrupts that are not being dealt with, do disable + * ADMA until this is sorted out. */ + host->quirks |= SDHCI_QUIRK_BROKEN_ADMA; + host->quirks |= SDHCI_QUIRK_32BIT_ADMA_SIZE; + +#ifndef CONFIG_MMC_SDHCI_S3C_DMA + + /* we currently see overruns on errors, so disable the SDMA + * support as well. */ + host->quirks |= SDHCI_QUIRK_BROKEN_DMA; + +#endif /* CONFIG_MMC_SDHCI_S3C_DMA */ + + /* It seems we do not get an DATA transfer complete on non-busy + * transfers, not sure if this is a problem with this specific + * SDHCI block, or a missing configuration that needs to be set. */ + host->quirks |= SDHCI_QUIRK_NO_BUSY_IRQ; + + host->quirks |= (SDHCI_QUIRK_32BIT_DMA_ADDR | + SDHCI_QUIRK_32BIT_DMA_SIZE); + + ret = sdhci_add_host(host); + if (ret) { + dev_err(dev, "sdhci_add_host() failed\n"); + goto err_add_host; + } + + return 0; + + err_add_host: + release_resource(sc->ioarea); + kfree(sc->ioarea); + + err_req_regs: + for (ptr = 0; ptr < MAX_BUS_CLK; ptr++) { + clk_disable(sc->clk_bus[ptr]); + clk_put(sc->clk_bus[ptr]); + } + + err_no_busclks: + clk_disable(sc->clk_io); + clk_put(sc->clk_io); + + err_io_clk: + sdhci_free_host(host); + + return ret; +} + +static int __devexit sdhci_s3c_remove(struct platform_device *pdev) +{ + return 0; +} + +#ifdef CONFIG_PM + +static int sdhci_s3c_suspend(struct platform_device *dev, pm_message_t pm) +{ + struct sdhci_host *host = platform_get_drvdata(dev); + + sdhci_suspend_host(host, pm); + return 0; +} + +static int sdhci_s3c_resume(struct platform_device *dev) +{ + struct sdhci_host *host = platform_get_drvdata(dev); + + sdhci_resume_host(host); + return 0; +} + +#else +#define sdhci_s3c_suspend NULL +#define sdhci_s3c_resume NULL +#endif + +static struct platform_driver sdhci_s3c_driver = { + .probe = sdhci_s3c_probe, + .remove = __devexit_p(sdhci_s3c_remove), + .suspend = sdhci_s3c_suspend, + .resume = sdhci_s3c_resume, + .driver = { + .owner = THIS_MODULE, + .name = "s3c-sdhci", + }, +}; + +static int __init sdhci_s3c_init(void) +{ + return platform_driver_register(&sdhci_s3c_driver); +} + +static void __exit sdhci_s3c_exit(void) +{ + platform_driver_unregister(&sdhci_s3c_driver); +} + +module_init(sdhci_s3c_init); +module_exit(sdhci_s3c_exit); + +MODULE_DESCRIPTION("Samsung SDHCI (HSMMC) glue"); +MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:s3c-sdhci"); |