[PATCH V7 1/5] AHCI Add the AHCI SATA feature on the MX53 platforms

Richard Zhu richard.zhu at linaro.org
Wed Sep 21 03:05:44 EDT 2011


Hi Sascha:
One proposal about how to convert the ahci driver to devicetree in future.
ahci driver system can make a reference to the evolution of the sdhc driver.

* separate the ahci to ahci common codes, ahci-pci driver and
ahci-platform driver.
* create kinds of ahci vendor's own ahci platform driver refer to the
sdhci-xxx driver solutions.
* then we can convert the ahci driver to devicetree smoothly.

It's a long term evolution.

Hi Jeff:
Do you have any suggestions or advices about it?

Best Regard
Richard Zhu

On 21 September 2011 13:04, Richard Zhu <richard.zhu at linaro.org> wrote:
> Hi Sascha:
> Thanks for your comments.
>
> Best Regard
> Richard Zhu
>
> On 21 September 2011 04:30, Sascha Hauer <s.hauer at pengutronix.de> wrote:
>> On Wed, Aug 31, 2011 at 11:50:31AM +0800, Richard Zhu wrote:
>>> Signed-off-by: Richard Zhu <richard.zhu at linaro.org>
>>> Tested-By: Hector Oron Martinez <hector.oron at gmail.com>
>>> ---
>>>  arch/arm/mach-mx5/clock-mx51-mx53.c             |   19 ++++
>>>  arch/arm/mach-mx5/devices-imx53.h               |    4 +
>>>  arch/arm/plat-mxc/Makefile                      |    1 +
>>>  arch/arm/plat-mxc/ahci_sata.c                   |  104 +++++++++++++++++++++++
>>>  arch/arm/plat-mxc/devices/Kconfig               |    4 +
>>>  arch/arm/plat-mxc/devices/Makefile              |    1 +
>>>  arch/arm/plat-mxc/devices/platform-ahci-imx.c   |   66 ++++++++++++++
>>>  arch/arm/plat-mxc/include/mach/ahci_sata.h      |   33 +++++++
>>>  arch/arm/plat-mxc/include/mach/devices-common.h |   10 ++
>>>  9 files changed, 242 insertions(+), 0 deletions(-)
>>>  create mode 100644 arch/arm/plat-mxc/ahci_sata.c
>>>  create mode 100644 arch/arm/plat-mxc/devices/platform-ahci-imx.c
>>>  create mode 100644 arch/arm/plat-mxc/include/mach/ahci_sata.h
>>>
>>> diff --git a/arch/arm/mach-mx5/clock-mx51-mx53.c b/arch/arm/mach-mx5/clock-mx51-mx53.c
>>> index 7f20308..e1fadaf 100644
>>> --- a/arch/arm/mach-mx5/clock-mx51-mx53.c
>>> +++ b/arch/arm/mach-mx5/clock-mx51-mx53.c
>>> @@ -1397,6 +1397,22 @@ static struct clk esdhc4_mx53_clk = {
>>>       .secondary = &esdhc4_ipg_clk,
>>>  };
>>>
>>> diff --git a/arch/arm/plat-mxc/ahci_sata.c b/arch/arm/plat-mxc/ahci_sata.c
>>> new file mode 100644
>>> index 0000000..4f54816
>>> --- /dev/null
>>> +++ b/arch/arm/plat-mxc/ahci_sata.c
>>> @@ -0,0 +1,104 @@
>>> +/*
>>> + * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
>>> + */
>>> +
>>> +/*
>>> + * 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; either version 2 of the License, or
>>> + * (at your option) any later version.
>>> +
>>> + * 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.,
>>> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
>>> + */
>>> +
>>> +#include <linux/io.h>
>>> +#include <linux/clk.h>
>>> +#include <linux/err.h>
>>> +#include <linux/device.h>
>>> +#include <mach/ahci_sata.h>
>>> +
>>> +static struct clk *sata_clk, *sata_ref_clk;
>>
>> These variables make the driver single instance only.
> [Richard Zhu] In order to handle the clock enable/disable stuff, these
> two variables are mandatory required.
> Otherwise, new two struct clk members had to be added into
> ahci_platform_data struct. Then the clks can
> be transferred by the platform data.
> The current is preferred, refer to the second choice.
>>
>>> +
>>> +/* AHCI module Initialization, if return 0, initialization is successful. */
>>> +int sata_init(struct device *dev, void __iomem *addr)
>>
>> A global function with such a generic name is not a good idea.
>> Also I wonder how we want to convert this to devicetree when we
>> implement this as a platform specific hook. It should be done in the
>> driver.
>>
> [Richard Zhu] The name of these two func can be changed.
> But I don't have a good idea to move out these two platform specific
> hooks (->init, ->exit).
>
> Refer to you comments, do you means that the ->init and ->exit should
> be done in ahci_platform.c driver?
> Different platform may have the different ->init and ->exit funcs to
> handle it's own initialization and exit.
> It would be a problem that handle all kinds of init in one driver
> without the hooks.
>
>>> +{
>>> +     u32 tmpdata;
>>> +     int ret = 0;
>>> +     struct clk *clk;
>>> +
>>> +     sata_clk = clk_get(dev, "ahci");
>>> +     if (IS_ERR(sata_clk)) {
>>> +             dev_err(dev, "no sata clock.\n");
>>> +             return PTR_ERR(sata_clk);
>>> +     }
>>> +     ret = clk_enable(sata_clk);
>>> +     if (ret) {
>>> +             dev_err(dev, "can't enable sata clock.\n");
>>> +             goto put_sata_clk;
>>> +     }
>>> +
>>> +     /* FSL IMX AHCI SATA uses the internal usb phy1 clk on loco */
>>
>> So this function is loco specific or is the comment wrong?
> [Richard Zhu] Comments wrong, they're common codes and should't be
> specified by the exact
>  board, would be changed later.
>>
>>> +     sata_ref_clk = clk_get(dev, "ahci_phy");
>>> +     if (IS_ERR(sata_ref_clk)) {
>>> +             dev_err(dev, "no sata ref clock.\n");
>>> +             ret = PTR_ERR(sata_ref_clk);
>>> +             goto release_sata_clk;
>>> +     }
>>> +     ret = clk_enable(sata_ref_clk);
>>> +     if (ret) {
>>> +             dev_err(dev, "can't enable sata ref clock.\n");
>>> +             goto put_sata_ref_clk;
>>> +     }
>>> +
>>> +     /* Get the AHB clock rate, and configure the TIMER1MS reg later */
>>> +     clk = clk_get(dev, "ahci_dma");
>>> +     if (IS_ERR(clk)) {
>>> +             dev_err(dev, "no dma clock.\n");
>>> +             ret = PTR_ERR(clk);
>>> +             goto release_sata_ref_clk;
>>> +     }
>>> +     tmpdata = clk_get_rate(clk) / 1000;
>>> +     clk_put(clk);
>>> +
>>> +     writel(tmpdata, addr + HOST_TIMER1MS);
>>> +
>>> +     tmpdata = readl(addr + HOST_CAP);
>>> +     if (!(tmpdata & HOST_CAP_SSS)) {
>>> +             tmpdata |= HOST_CAP_SSS;
>>> +             writel(tmpdata, addr + HOST_CAP);
>>> +     }
>>> +
>>> +     if (!(readl(addr + HOST_PORTS_IMPL) & 0x1))
>>> +             writel((readl(addr + HOST_PORTS_IMPL) | 0x1),
>>> +                     addr + HOST_PORTS_IMPL);
>>> +
>>> +     return 0;
>>> +
>>> +release_sata_ref_clk:
>>> +     clk_disable(sata_ref_clk);
>>> +put_sata_ref_clk:
>>> +     clk_put(sata_ref_clk);
>>> +release_sata_clk:
>>> +     clk_disable(sata_clk);
>>> +put_sata_clk:
>>> +     clk_put(sata_clk);
>>> +
>>> +     return ret;
>>> +}
>>> +
>>> +void sata_exit(struct device *dev)
>>> +{
>>> +     clk_disable(sata_ref_clk);
>>> +     clk_put(sata_ref_clk);
>>> +
>>> +     clk_disable(sata_clk);
>>> +     clk_put(sata_clk);
>>> +
>>> +}
>>> diff --git a/arch/arm/plat-mxc/devices/Kconfig b/arch/arm/plat-mxc/devices/Kconfig
>>> index bd294ad..f63887b 100644
>>> --- a/arch/arm/plat-mxc/devices/Kconfig
>>> +++ b/arch/arm/plat-mxc/devices/Kconfig
>>> @@ -76,3 +76,7 @@ config IMX_HAVE_PLATFORM_SDHCI_ESDHC_IMX
>>>
>>>  config IMX_HAVE_PLATFORM_SPI_IMX
>>>       bool
>>> +
>>> +config IMX_HAVE_PLATFORM_AHCI
>>> +     bool
>>> +     default y if ARCH_MX53
>>> diff --git a/arch/arm/plat-mxc/devices/Makefile b/arch/arm/plat-mxc/devices/Makefile
>>> index b41bf97..e858ad9 100644
>>> --- a/arch/arm/plat-mxc/devices/Makefile
>>> +++ b/arch/arm/plat-mxc/devices/Makefile
>>> @@ -25,3 +25,4 @@ obj-$(CONFIG_IMX_HAVE_PLATFORM_MXC_RTC) += platform-mxc_rtc.o
>>>  obj-$(CONFIG_IMX_HAVE_PLATFORM_MXC_W1) += platform-mxc_w1.o
>>>  obj-$(CONFIG_IMX_HAVE_PLATFORM_SDHCI_ESDHC_IMX) += platform-sdhci-esdhc-imx.o
>>>  obj-$(CONFIG_IMX_HAVE_PLATFORM_SPI_IMX) +=  platform-spi_imx.o
>>> +obj-$(CONFIG_IMX_HAVE_PLATFORM_AHCI) +=  platform-ahci-imx.o
>>> diff --git a/arch/arm/plat-mxc/devices/platform-ahci-imx.c b/arch/arm/plat-mxc/devices/platform-ahci-imx.c
>>> new file mode 100644
>>> index 0000000..9e1b460
>>> --- /dev/null
>>> +++ b/arch/arm/plat-mxc/devices/platform-ahci-imx.c
>>> @@ -0,0 +1,66 @@
>>> +/*
>>> + * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
>>> + */
>>> +
>>> +/*
>>> + * 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; either version 2 of the License, or
>>> + * (at your option) any later version.
>>> +
>>> + * 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.,
>>> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
>>> + */
>>> +
>>> +#include <linux/dma-mapping.h>
>>> +#include <asm/sizes.h>
>>> +#include <mach/hardware.h>
>>> +#include <mach/devices-common.h>
>>> +#include <mach/ahci_sata.h>
>>> +
>>> +#define imx_ahci_imx_data_entry_single(soc, _devid)          \
>>> +     {                                                               \
>>> +             .devid = _devid,                                        \
>>> +             .iobase = soc ## _SATA_BASE_ADDR,                       \
>>> +             .irq = soc ## _INT_SATA,                                \
>>> +     }
>>> +
>>> +#ifdef CONFIG_SOC_IMX53
>>> +const struct imx_ahci_imx_data imx53_ahci_imx_data __initconst =
>>> +     imx_ahci_imx_data_entry_single(MX53, "imx53-ahci");
>>> +#endif
>>> +
>>> +static struct ahci_platform_data default_sata_pdata = {
>>> +     .init = sata_init,
>>> +     .exit = sata_exit,
>>> +};
>>> +
>>> +struct platform_device *__init imx_add_ahci_imx(
>>> +             const struct imx_ahci_imx_data *data,
>>> +             const struct ahci_platform_data *pdata)
>>> +{
>>> +     struct resource res[] = {
>>> +             {
>>> +                     .start = data->iobase,
>>> +                     .end = data->iobase + SZ_4K - 1,
>>> +                     .flags = IORESOURCE_MEM,
>>> +             }, {
>>> +                     .start = data->irq,
>>> +                     .end = data->irq,
>>> +                     .flags = IORESOURCE_IRQ,
>>> +             },
>>> +     };
>>> +
>>> +     if (pdata == NULL)
>>> +             pdata = &default_sata_pdata;
>>> +
>>> +     return imx_add_platform_device_dmamask(data->devid, 0,
>>> +                     res, ARRAY_SIZE(res),
>>> +                     pdata, sizeof(*pdata),  DMA_BIT_MASK(32));
>>> +}
>>> diff --git a/arch/arm/plat-mxc/include/mach/ahci_sata.h b/arch/arm/plat-mxc/include/mach/ahci_sata.h
>>> new file mode 100644
>>> index 0000000..ba297e1
>>> --- /dev/null
>>> +++ b/arch/arm/plat-mxc/include/mach/ahci_sata.h
>>> @@ -0,0 +1,33 @@
>>> +/*
>>> + * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
>>> + */
>>> +
>>> +/*
>>> + * 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; either version 2 of the License, or
>>> + * (at your option) any later version.
>>> +
>>> + * 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.,
>>> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
>>> + */
>>> +
>>> +#ifndef __PLAT_MXC_AHCI_SATA_H__
>>> +#define __PLAT_MXC_AHCI_SATA_H__
>>> +
>>> +enum {
>>> +     HOST_CAP = 0x00,
>>> +     HOST_CAP_SSS = (1 << 27), /* Staggered Spin-up */
>>> +     HOST_PORTS_IMPL = 0x0c,
>>> +     HOST_TIMER1MS = 0xe0, /* Timer 1-ms */
>>> +};
>>> +
>>> +extern int sata_init(struct device *dev, void __iomem *addr);
>>> +extern void sata_exit(struct device *dev);
>>> +#endif /* __PLAT_MXC_AHCI_SATA_H__ */
>>> diff --git a/arch/arm/plat-mxc/include/mach/devices-common.h b/arch/arm/plat-mxc/include/mach/devices-common.h
>>> index 524538a..f04e063 100644
>>> --- a/arch/arm/plat-mxc/include/mach/devices-common.h
>>> +++ b/arch/arm/plat-mxc/include/mach/devices-common.h
>>> @@ -301,3 +301,13 @@ struct platform_device *__init imx_add_spi_imx(
>>>  struct platform_device *imx_add_imx_dma(void);
>>>  struct platform_device *imx_add_imx_sdma(char *name,
>>>       resource_size_t iobase, int irq, struct sdma_platform_data *pdata);
>>> +
>>> +#include <linux/ahci_platform.h>
>>> +struct imx_ahci_imx_data {
>>> +     const char *devid;
>>> +     resource_size_t iobase;
>>> +     resource_size_t irq;
>>> +};
>>> +struct platform_device *__init imx_add_ahci_imx(
>>> +             const struct imx_ahci_imx_data *data,
>>> +             const struct ahci_platform_data *pdata);
>>> --
>>> 1.7.1
>>>
>>>
>>>
>>
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