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 [off-list ref] wrote:

Hi Sascha:
Thanks for your comments.

Best Regard
Richard Zhu

On 21 September 2011 04:30, Sascha Hauer [off-list ref] wrote:

quoted

On Wed, Aug 31, 2011 at 11:50:31AM +0800, Richard Zhu wrote:

quoted

Signed-off-by: Richard Zhu <redacted>
Tested-By: Hector Oron Martinez <redacted>
---
?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.

quoted

quoted

+
+/* 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.

quoted

quoted

+{
+ ? ? 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.

quoted

quoted

+ ? ? 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

--
Pengutronix e.K. ? ? ? ? ? ? ? ? ? ? ? ? ? | ? ? ? ? ? ? ? ? ? ? ? ? ? ? |
Industrial Linux Solutions ? ? ? ? ? ? ? ? | http://www.pengutronix.de/ ?|
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 ? ?|
Amtsgericht Hildesheim, HRA 2686 ? ? ? ? ? | Fax: ? +49-5121-206917-5555 |