[PATCH 8/9] esdhc-4 esdhc: fsl esdhc driver based on platform sdhci api
Zhu Richard-R65037
r65037 at freescale.com
Tue Sep 7 05:32:32 EDT 2010
Hi Wolfram:
See my comments below. Marked by [<Zhu Richard-r65037>]
Best Regards,
Richard Zhu
Freescale Semiconductor
Tel: +86-021-28937189
Email:Hong-Xing.Zhu at freescale.com
-----Original Message-----
From: Wolfram Sang [mailto:w.sang at pengutronix.de]
Sent: Monday, 6 September, 2010 18:47
To: Zhu Richard-R65037
Cc: linux-mmc at vger.kernel.org; kernel at pengutronix.de;
linux-arm-kernel at lists.infradead.org
Subject: Re: [PATCH 8/9] esdhc-4 esdhc: fsl esdhc driver based on
platform sdhci api
On Wed, Sep 01, 2010 at 05:48:53PM +0800, Richard Zhu wrote:
> Based on SDHCI platform API, PIO and simple internal DMA are enabled.
>
> Signed-off-by: Richard Zhu <r65037 at freescale.com>
> ---
> drivers/mmc/host/Kconfig | 12 +
> drivers/mmc/host/Makefile | 1 +
> drivers/mmc/host/sdhci-fsl.c | 481
> ++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 494 insertions(+), 0 deletions(-) create mode
> 100644 drivers/mmc/host/sdhci-fsl.c
>
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig index
> 283190b..2b67e11 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -167,6 +167,18 @@ config MMC_SDHCI_S3C_DMA
>
> YMMV.
>
> +config MMC_SDHCI_FSL
> + tristate "Freescale i.MX platform eSDHCI support"
> + depends on ARCH_MX5 && MMC_SDHCI
> + select MMC_SDHCI_IO_ACCESSORS
> + help
> + This selects the Freescale i.MX Enhanced Secure Card Host
> + Controller Interface.
> + If you have a i.MX platform with a Multimedia Card slot,
> + say Y or M here.
> +
> + If unsure, say N.
> +
> 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 840bcb5..649656c 100644
> --- a/drivers/mmc/host/Makefile
> +++ b/drivers/mmc/host/Makefile
> @@ -13,6 +13,7 @@ obj-$(CONFIG_MMC_MXC) += mxcmmc.o
> obj-$(CONFIG_MMC_SDHCI) += sdhci.o
> obj-$(CONFIG_MMC_SDHCI_PCI) += sdhci-pci.o
> obj-$(CONFIG_MMC_SDHCI_S3C) += sdhci-s3c.o
> +obj-$(CONFIG_MMC_SDHCI_FSL) += sdhci-fsl.o
> obj-$(CONFIG_MMC_SDHCI_SPEAR) += sdhci-spear.o
> obj-$(CONFIG_MMC_WBSD) += wbsd.o
> obj-$(CONFIG_MMC_AU1X) += au1xmmc.o
> diff --git a/drivers/mmc/host/sdhci-fsl.c
> b/drivers/mmc/host/sdhci-fsl.c new file mode 100644 index
> 0000000..fa57ec4
> --- /dev/null
> +++ b/drivers/mmc/host/sdhci-fsl.c
> @@ -0,0 +1,481 @@
> +/*
> + * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights
Reserved.
> + */
> +
> +/*
> + * sdhci-fsl.c Support for SDHCI platform devices
> + *
> + * 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.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
> + */
> +
> +/* Supports:
> + * SDHCI fsl devices
> + *
> + * Inspired by sdhci-pci.c, by Pierre Ossman */
> +
> +#include <linux/delay.h>
> +#include <linux/highmem.h>
> +#include <linux/platform_device.h>
> +#include <linux/clk.h>
> +#include <linux/regulator/consumer.h> #include <linux/io.h> #include
> +<linux/irq.h> #include <linux/mmc/host.h>
> +
> +#include <mach/mmc.h>
> +
> +#include "sdhci.h"
> +
> +#define DRIVER_NAME "imx-sdhci"
> +
> +enum {
> + /* Vendor specified registors */
> + FSL_SDHCI_WML = 0x44,
> + FSL_SDHCI_WML_16_WORDS = 0x08100810,
> + FSL_SDHCI_WML_32_WORDS = 0x08200820,
> + FSL_SDHCI_WML_64_WORDS = 0x08400840,
> + FSL_SDHCI_WML_128_WORDS = 0x08800880,
> +
> + /* Non-standard clock control registor */
> + FSL_SDHCI_CLOCK_MASK = 0xFFFF,
> + FSL_SDHCI_CLOCK_SD_EN = 0x00000008,
> + FSL_SDHCI_CLOCK_HLK_EN = 0x00000002,
> +
> + /* Non-standard host control registor */
> + FSL_SDHCI_CTRL_8BITBUS = 0x00000004,
> +};
> +
>
+/**********************************************************************
*******\
> + *
*
> + * SDHCI core callbacks
*
> + *
*
> +\********************************************************************
> +*********/
> +
> +struct sdhci_fsl_host {
> + struct sdhci_host *host;
> + struct platform_device *pdev; /*! Platform dev */
> + struct imxmmc_platform_data *pdata; /*! private data */
> + struct clk *clk_input; /*! Clock */
> + struct regulator *regulator_mmc; /*! Regulator */
> +};
> +
> +static u32 sdhci_fsl_readl(struct sdhci_host *host, int reg) {
> + return readl(host->ioaddr + reg);
> +}
> +
> +static u16 sdhci_fsl_readw(struct sdhci_host *host, int reg) {
> + u32 val;
> + u16 rc;
> +
> + if (reg % 4 == 3) {
> + printk(KERN_ERR "Invalid reg address!\n");
> + return 0;
> + }
> +
> + val = readl(host->ioaddr + (reg / 4) * 4);
> + rc = (val >> (reg % 4) * 8) & 0xFFFF;
> +
> + return rc;
> +}
> +
> +static u8 sdhci_fsl_readb(struct sdhci_host *host, int reg) {
> + u32 val;
> + u8 rc;
> +
> + val = readl(host->ioaddr + (reg / 4) * 4);
> + rc = (val >> (reg % 4) * 8) & 0xFF;
> +
> + return rc;
> +}
> +
> +static void sdhci_fsl_writel(struct sdhci_host *host, u32 val, int
> +reg) {
> + writel(val, host->ioaddr + reg);
> +}
> +
> +static void sdhci_fsl_writew(struct sdhci_host *host, u16 val, int
> +reg) {
> + u32 io_val;
> +
> + if (reg % 4 == 3) {
> + printk(KERN_ERR "Invalid reg address!\n");
> + return;
> + }
> +
> + io_val = readl(host->ioaddr + (reg / 4) * 4);
> + io_val &= ~(0xFFFF << ((reg % 4) * 8));
> + io_val |= val << ((reg % 4) * 8);
> +
> + writel(io_val, host->ioaddr + (reg / 4) * 4); }
> +
> +static void sdhci_fsl_writeb(struct sdhci_host *host, u8 val, int
> +reg) {
> + u32 io_val;
> +
> + io_val = readl(host->ioaddr + (reg / 4) * 4);
> + io_val &= ~(0xFF << ((reg % 4) * 8));
> + io_val |= val << ((reg % 4) * 8);
> +
> + writel(io_val, host->ioaddr + (reg / 4) * 4); }
> +
> +static unsigned int sdhci_fsl_get_max_clock(struct sdhci_host *host)
> +{
> + struct sdhci_fsl_host *fsl_host = sdhci_priv(host);
> +
> + return fsl_host->pdata->max_clk;
> +}
> +
> +static unsigned int sdhci_fsl_get_min_clock(struct sdhci_host *host)
> +{
> + struct sdhci_fsl_host *fsl_host = sdhci_priv(host);
> +
> + return fsl_host->pdata->min_clk;
> +}
> +
> +static unsigned int sdhci_fsl_get_timeout_clock(struct sdhci_host
> +*host) {
> + return sdhci_fsl_get_max_clock(host) / 1000000; }
> +
> +static unsigned int sdhci_fsl_get_ro(struct sdhci_host *host) {
> + struct sdhci_fsl_host *fsl_host = sdhci_priv(host);
> +
> + return fsl_host->pdata->wp_status(host->mmc->parent);
> +}
Is there really no way to route the WP-GPIO to the SD_WP pin of the
controller (sigh)? Still, I'd think we can be more abstract by using the
gpiolib and just pass the gpio number in the platform-data?
[<Zhu Richard-r65037>] Up to now, refer to the limitations of the HW
design on the different boards, the WP-GPIO mechanism is used.
About the more abstract method by passing the GPIO number in the
platform-data.
Do you means that just pass the GPIO number in the sdhci_pltfm_data
defined in sdhci_pltfm_data.h file?
I don't think we can do that, because the WP-GPIO pins maybe different
refer to different boards.
The definition of the private platform_data should be related to the
definite HW board, otherwise the abstract sdhci platform driver layer.
> +
> +static void sdhci_fsl_set_clock(struct sdhci_host *host, unsigned int
> +clock) {
> + /*This variable holds the value of clock divider, prescaler */
> + int div = 0, prescaler = 1;
> + int clk_rate = 0;
> + u32 clk;
> + unsigned long timeout;
> + struct sdhci_fsl_host *fsl_host = sdhci_priv(host);
> +
> + if (clock == 0) {
> + host->clock = 0;
> + clk = readl(host->ioaddr + SDHCI_CLOCK_CONTROL);
> + writel(clk & (~FSL_SDHCI_CLOCK_HLK_EN),
> + host->ioaddr + SDHCI_CLOCK_CONTROL);
> + return;
> + }
> +
> + clk_rate = clk_get_rate(fsl_host->clk_input);
> + clk = readl(host->ioaddr + SDHCI_CLOCK_CONTROL) &
~FSL_SDHCI_CLOCK_MASK;
> + /* precaler can't be set to zero in CLK_CTL reg */
> + clk |= (prescaler << 8);
> + writel(clk, host->ioaddr + SDHCI_CLOCK_CONTROL);
> +
> + if (clock == sdhci_fsl_get_min_clock(host))
> + prescaler = 0x10;
> +
> + while (prescaler <= 0x80) {
> + for (div = 0; div <= 0xF; div++) {
> + int x;
> + if (prescaler != 0)
> + x = (clk_rate / (div + 1)) / (prescaler
* 2);
> + else
> + x = clk_rate / (div + 1);
> +
> + dev_dbg(&fsl_host->pdev->dev, "x=%d, clock=%d
%d\n",
> + x, clock, div);
> + if (x <= clock)
> + break;
> + }
> + if (div < 0x10)
> + break;
> +
> + prescaler <<= 1;
> + }
> + dev_dbg(&fsl_host->pdev->dev, "prescaler = 0x%x, divider =
0x%x\n",
> + prescaler, div);
> + clk |= (prescaler << 8) | (div << 4);
> +
> + /* Configure the clock control register */
> + clk |= readl(host->ioaddr + SDHCI_CLOCK_CONTROL)
> + & (~FSL_SDHCI_CLOCK_MASK);
> + clk |= FSL_SDHCI_CLOCK_HLK_EN;
> + writel(clk, host->ioaddr + SDHCI_CLOCK_CONTROL);
> +
> + /* Wait max 10 ms */
> + timeout = 5000;
> + while (timeout > 0) {
> + timeout--;
> + udelay(20);
> + }
> + writel(clk | FSL_SDHCI_CLOCK_SD_EN, host->ioaddr +
> +SDHCI_CLOCK_CONTROL);
> +
> + host->clock = (clk_rate / (div + 1)) / (prescaler * 2); }
Do you know if there is an improvement over the set_clock-routine in
sdhic-of-esdhc.c?
[<Zhu Richard-r65037>] Accepted.
> +
> +static void sdhci_fsl_set_power(struct sdhci_host *host, unsigned int
> +power) {
> + struct sdhci_fsl_host *fsl_host = sdhci_priv(host);
> + int voltage = 0;
> +
> + /* There is no sdhci standard PWR CTL REG in fsl esdhci */
> + if (host->pwr == power)
> + return;
> +
> + if (fsl_host->regulator_mmc) {
> + if (power == (unsigned short)-1) {
> + regulator_disable(fsl_host->regulator_mmc);
> + dev_dbg(&fsl_host->pdev->dev, "mmc power
off\n");
> + } else {
> + if (power == 7)
> + voltage = 1800000;
> + else if (power >= 8)
> + voltage = 2000000 + (power - 8) *
100000;
> + regulator_set_voltage(fsl_host->regulator_mmc,
> + voltage, voltage);
> +
> + if (regulator_enable(fsl_host->regulator_mmc) ==
0) {
> + dev_dbg(&fsl_host->pdev->dev, "mmc power
on\n");
> + msleep(1);
> + }
> + }
> + }
> +
> + host->pwr = power;
> +}
The host-structure has a regulator, too. We should use that. Note that
my boards don't have such a regulator, so I can't test here.
[<Zhu Richard-r65037>] Accepted.
> +
> +static void sdhci_fsl_set_bus(struct sdhci_host *host, unsigned int
> +bus_width) {
> + u32 ctrl;
> +
> + ctrl = readl(host->ioaddr + SDHCI_HOST_CONTROL);
> +
> + if (bus_width == MMC_BUS_WIDTH_4) {
> + ctrl &= ~FSL_SDHCI_CTRL_8BITBUS;
> + ctrl |= SDHCI_CTRL_4BITBUS;
> + } else if (bus_width == MMC_BUS_WIDTH_8) {
> + ctrl &= ~SDHCI_CTRL_4BITBUS;
> + ctrl |= FSL_SDHCI_CTRL_8BITBUS;
> + } else if (bus_width == MMC_BUS_WIDTH_1) {
> + ctrl &= ~SDHCI_CTRL_4BITBUS;
> + ctrl &= ~FSL_SDHCI_CTRL_8BITBUS;
> + }
I'd be careful with the 8Bit-mode for now. We need some to deal with it
correctly in sdhci.c first.
[<Zhu Richard-r65037>] Are there some problems in the 8bits bus_width in
sdhci.c file?
I find that the sdhci.c had been support the 8bits bus_width.
> +
> + writel(ctrl, host->ioaddr + SDHCI_HOST_CONTROL); }
> +
> +static u16 sdhci_fsl_make_blksz(u16 blk_sz) {
> + return blk_sz &= 0x1FFF;
> +}
> +
> +static int esdhci_fsl_enable_dma(struct sdhci_host *host) {
> + u32 ctrl;
> +
> + ctrl = readl(host->ioaddr + SDHCI_HOST_CONTROL);
> + ctrl &= ~(SDHCI_CTRL_DMA_MASK << 5);
> + if ((host->flags & SDHCI_REQ_USE_DMA) &&
> + (host->flags & SDHCI_USE_ADMA))
> + ctrl |= (SDHCI_CTRL_ADMA32 << 8);
> + else if (host->flags & SDHCI_REQ_USE_DMA)
> + ctrl |= (SDHCI_CTRL_SDMA << 8);
> +
> + writel(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);
> +
> + if (host->flags & SDHCI_REQ_USE_DMA)
> + writel(FSL_SDHCI_WML_64_WORDS,
> + host->ioaddr + FSL_SDHCI_WML);
> + else
> + writel(FSL_SDHCI_WML_128_WORDS,
> + host->ioaddr + FSL_SDHCI_WML);
> + return 0;
> +}
> +
> +static const struct sdhci_ops sdhci_fsl_ops = {
> + .read_l = sdhci_fsl_readl,
> + .read_w = sdhci_fsl_readw,
> + .read_b = sdhci_fsl_readb,
> + .write_l = sdhci_fsl_writel,
> + .write_w = sdhci_fsl_writew,
> + .write_b = sdhci_fsl_writeb,
> + .set_clock = sdhci_fsl_set_clock,
> + .set_power = sdhci_fsl_set_power,
> + .set_bus = sdhci_fsl_set_bus,
> + .enable_dma = esdhci_fsl_enable_dma,
> + .get_max_clock = sdhci_fsl_get_max_clock,
> + .get_min_clock = sdhci_fsl_get_min_clock,
> + .get_timeout_clock = sdhci_fsl_get_timeout_clock,
> + .get_ro = sdhci_fsl_get_ro,
> + .make_blksz = sdhci_fsl_make_blksz,
> +};
> +
>
+/**********************************************************************
*******\
> + *
*
> + * Device probing/removal
*
> + *
*
> +\********************************************************************
> +*********/
> +
> +static int __devinit sdhci_fsl_probe(struct platform_device *pdev) {
> + struct sdhci_host *host;
> + struct resource *iomem;
> + struct sdhci_fsl_host *fsl_host;
> + int ret;
> + struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
> +
> + BUG_ON(pdev == NULL);
> +
> + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!iomem) {
> + ret = -ENOMEM;
> + goto err;
> + }
> +
> + host = sdhci_alloc_host(&pdev->dev, sizeof(struct
sdhci_fsl_host));
> +
> + if (IS_ERR(host)) {
> + ret = PTR_ERR(host);
> + goto err;
> + }
> +
> + fsl_host = sdhci_priv(host);
> +
> + fsl_host->host = host;
> + fsl_host->pdev = pdev;
> + fsl_host->pdata = pdata;
> +
> + /* Get clk supply for eSDHC */
> + fsl_host->clk_input = clk_get(&pdev->dev, "esdhc_clk");
> + if (IS_ERR(fsl_host->clk_input)) {
> + ret = PTR_ERR(fsl_host->clk_input);
> + printk(KERN_ERR "IMX MMC can't get clock.\n");
> + goto err_request_clk;
> + }
> + clk_enable(fsl_host->clk_input);
> +
> + dev_dbg(&pdev->dev, "SDHC:%d clock:%lu\n",
> + pdev->id, clk_get_rate(fsl_host->clk_input));
> +
> + host->hw_name = "sdhci-fsl";
> + host->ops = &sdhci_fsl_ops;
> + host->irq = platform_get_irq(pdev, 0);
> +
> + host->quirks = SDHCI_QUIRK_BROKEN_ADMA
Why did you add all the DMA-stuff and mark it as broken then?
Is there a problem with the engine?
[<Zhu Richard-r65037>] The ADMA is broken, and I still can't find the
root cause.
I would enable the ADMA feature later.
Up to now, the Simple DMA and PIO mode are enabled.
> + | SDHCI_QUIRK_32BIT_DMA_ADDR
> + | SDHCI_QUIRK_32BIT_ADMA_SIZE
> + | SDHCI_QUIRK_BROKEN_TIMEOUT_VAL
> + | SDHCI_QUIRK_NO_BUSY_IRQ
> + | SDHCI_QUIRK_BROKEN_CARD_DETECTION
> + | SDHCI_QUIRK_NONSTANDARD_CLOCK
> + | SDHCI_QUIRK_RESTORE_IRQS_AFTER_RESET
> + | SDHCI_QUIRK_32BIT_CMD_TRANS_COMBINATION
> + | SDHCI_QUIRK_NONSTANDARD_HOST_CTL;
> + if (!request_mem_region(iomem->start, resource_size(iomem),
> + mmc_hostname(host->mmc))) {
> + dev_err(&pdev->dev, "cannot request region\n");
> + ret = -EBUSY;
> + goto err_request_mem;
> + }
> +
> + host->ioaddr = ioremap(iomem->start, resource_size(iomem));
> + if (!host->ioaddr) {
> + dev_err(&pdev->dev, "failed to remap registers\n");
> + ret = -ENOMEM;
> + goto err_remap;
> + }
> +
> + ret = sdhci_add_host(host);
> + if (ret)
> + goto err_add_host;
> +
> + platform_set_drvdata(pdev, host);
> +
> + return 0;
> +
> +err_add_host:
> + iounmap(host->ioaddr);
> +err_remap:
> + release_mem_region(iomem->start, resource_size(iomem));
> +err_request_mem:
> + if (fsl_host->clk_input) {
> + clk_disable(fsl_host->clk_input);
> + clk_put(fsl_host->clk_input);
> + }
> +err_request_clk:
> + if (fsl_host->regulator_mmc) {
> + regulator_disable(fsl_host->regulator_mmc);
> + regulator_put(fsl_host->regulator_mmc);
> + }
> + sdhci_free_host(host);
> +err:
> + printk(KERN_ERR"Probing of sdhci-pltfm failed: %d\n", ret);
> + return ret;
> +}
> +
> +static int __devexit sdhci_fsl_remove(struct platform_device *pdev) {
> + struct sdhci_host *host = platform_get_drvdata(pdev);
> + struct resource *iomem = platform_get_resource(pdev,
IORESOURCE_MEM, 0);
> + int dead;
> + u32 scratch;
> +
> + dead = 0;
> + scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
> + if (scratch == (u32)-1)
> + dead = 1;
> +
> + sdhci_remove_host(host, dead);
> + iounmap(host->ioaddr);
> + release_mem_region(iomem->start, resource_size(iomem));
> + sdhci_free_host(host);
> + platform_set_drvdata(pdev, NULL);
> +
> + return 0;
> +}
> +
> +static struct platform_driver sdhci_fsl_driver = {
> + .driver = {
> + .name = DRIVER_NAME,
> + .owner = THIS_MODULE,
> + },
> + .probe = sdhci_fsl_probe,
> + .remove = __devexit_p(sdhci_fsl_remove),
> +};
> +
>
+/**********************************************************************
*******\
> + *
*
> + * Driver init/exit
*
> + *
*
> +\********************************************************************
> +*********/
> +
> +static int __init sdhci_fsl_init(void) {
> + return platform_driver_register(&sdhci_fsl_driver);
> +}
> +
> +static void __exit sdhci_fsl_exit(void) {
> + platform_driver_unregister(&sdhci_fsl_driver);
> +}
> +
> +module_init(sdhci_fsl_init);
> +module_exit(sdhci_fsl_exit);
> +
> +MODULE_DESCRIPTION("IMX Secure Digital Host Controller Interface
> +driver"); MODULE_AUTHOR("Freescale Semiconductor, Inc.");
> +MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:sdhci-fsl");
> --
> 1.7.0
>
>
--
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