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

From: Richard Zhu <richard.zhu@linaro.org>
To: Sascha Hauer <s.hauer@pengutronix.de>
Cc: linux-arm-kernel@lists.infradead.org, jgarzik@pobox.com,
	kernel@pengutronix.de, linux-ide@vger.kernel.org,
	avorontsov@ru.mvista.com, eric@eukrea.com, eric.miao@linaro.org
Subject: Re: [PATCH V7 1/5] AHCI Add the AHCI SATA feature on the MX53 platforms
Date: Wed, 21 Sep 2011 13:04:09 +0800	[thread overview]
Message-ID: <CAJNCFVJ4EGQQ2CcRsPK6OidbU2uBEDertn8R9BuqxYGSBmxbPg@mail.gmail.com> (raw)
In-Reply-To: <20110920203037.GE31404@pengutronix.de>

Hi Sascha:
Thanks for your comments.

Best Regard
Richard Zhu

On 21 September 2011 04:30, Sascha Hauer <s.hauer@pengutronix.de> wrote:
> On Wed, Aug 31, 2011 at 11:50:31AM +0800, Richard Zhu wrote:
>> Signed-off-by: Richard Zhu <richard.zhu@linaro.org>
>> Tested-By: Hector Oron Martinez <hector.oron@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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