diff mbox

[v3,3/4] ata: Add APM X-Gene SoC SATA host controller driver

Message ID 1384465153-29902-4-git-send-email-lho@apm.com
State Not Applicable
Delegated to: David Miller
Headers show

Commit Message

Loc Ho Nov. 14, 2013, 9:39 p.m. UTC
ata: Add APM X-Gene SoC SATA host controller driver

This patch adds support for the APM X-Gene SoC SATA host controller driver.

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Tuan Phan <tphan@apm.com>
Signed-off-by: Suman Tripathi <stripathi@apm.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Olof Johansson <olof@lixom.net>
---
 drivers/ata/Kconfig      |    8 +
 drivers/ata/Makefile     |    1 +
 drivers/ata/sata_xgene.c | 1271 ++++++++++++++++++++++++++++++++++++++++++++++
 drivers/ata/sata_xgene.h |   96 ++++
 4 files changed, 1376 insertions(+), 0 deletions(-)
 create mode 100644 drivers/ata/sata_xgene.c
 create mode 100644 drivers/ata/sata_xgene.h

Comments

Arnd Bergmann Nov. 15, 2013, 1:48 p.m. UTC | #1
On Thursday 14 November 2013, Loc Ho wrote:
>  
> +config SATA_XGENE
> +	tristate "APM X-Gene 6.0Gbps SATA host controller support"
> +	depends on SATA_AHCI_PLATFORM
> +	default y if ARM64
> +	select SATA_XGENE_PHY

I don't think the "default y" is appropriate here, since there are going to
be lots of ARM64 platforms in the long run that don't have this. Also,
there is a trend towards using CONFIG_COMPILE_TEST to limit the
visibility.

I'd suggest something like

config SATA_XGENE
	tristate "APM X-Gene 6.0Gbps SATA host controller support"
	depends on ARM64 || COMPILE_TEST
	...

> +/* Enable for dumping CSR read/write access */
> +#undef XGENE_DBG_CSR

This should be removed now as well, along with the debug macro you already removed.

> +
> +/* Temporary function until the PHY parameter API */
> +extern void xgene_ahci_phy_set_pq(struct phy *phy, int chan, int data);
> +extern void xgene_ahci_phy_set_spd(struct phy *phy, int chan, int gen);

Ah, that should have been mentioned in the changeset text. Do you think you
can remove these for the final version?

> +static void xgene_rd(void *addr, u32 *val)
> +{
> +	*val = readl(addr);
> +#if defined(XGENE_DBG_CSR)
> +	printk(KERN_DEBUG "SATAPHY CSR RD: 0x%p value: 0x%08x\n", addr, *val);
> +#endif
> +}

The interface you are looking for is pr_debug() or dev_dbg(), which get
built-in only if the DEBUG macro is set.

In a lot of cases, it's actually best to remove debug output like this from
the driver once you have it working  -- whoever is debugging problems in 
the driver next might need completely different debugging information or
can add them back easily if needed.

It's your choice if you want to use pr_debug() or remove that output
entirely. If you remove it, best remove the helper functions entirely
and use readl/writel directly.

> +/* Flush the IOB to ensure all SATA controller writes completed before
> +   servicing the completed command. */
> +static int xgene_ahci_iob_flush(struct xgene_ahci_context *ctx)
> +{
> +	if (ctx->ahbc_io_base == NULL) {
> +		void *ahbc_base;
> +		u32 val;
> +
> +		/* The AHBC address is fixed in X-Gene */
> +		ahbc_base = devm_ioremap(ctx->dev, 0x1F2A0000, 0x80000);
> +		if (!ahbc_base) {
> +			dev_err(ctx->dev, "can't map AHBC resource\n");
> +			return -ENODEV;
> +		}

I had an important comment about the misuse of hardcoded I/O addresses
here. Please never just post a new version with the same issue. In general,
your options are:

* rewrite the code in a more appropriate way
* reply to the comment, arguing why you think your code is correct
* ask for clarification if you don't know how to improve the code
* mark the code as TODO and mention in the patch description why you
  are still working on this and that the current version should not
  be seen as final.

If you don't do any of these, reviewers will get annoyed because you
are wasting their time.
> +
> +static int xgene_ahci_get_u32_param(struct platform_device *pdev,
> +				    const char *of_name, char *acpi_name,
> +				    u32 *param)
> +{
> +#ifdef CONFIG_ACPI
> +	if (efi_enabled(EFI_BOOT)) {
> +		unsigned long long value;
> +		acpi_status status;
> +		if (acpi_name == NULL)
> +			return -ENODEV;
> +		status = acpi_evaluate_integer(ACPI_HANDLE(&pdev->dev),
> +					       acpi_name, NULL, &value);
> +		if (ACPI_FAILURE(status))
> +			return -ENODEV;
> +		*param = value;
> +		return 0;
> +	}
> +#endif

There are more previous comments that you have not addressed yet.

> diff --git a/drivers/ata/sata_xgene.h b/drivers/ata/sata_xgene.h
> new file mode 100644
> index 0000000..51e73f6
> --- /dev/null
> +++ b/drivers/ata/sata_xgene.h

This file should probably just be folded into the driver, since it contains no
interfaces between  modules, just internal definitions.

	Arnd
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Loc Ho Nov. 16, 2013, 6:36 a.m. UTC | #2
Hi,

>> +config SATA_XGENE
>> +     tristate "APM X-Gene 6.0Gbps SATA host controller support"
>> +     depends on SATA_AHCI_PLATFORM
>> +     default y if ARM64
>> +     select SATA_XGENE_PHY
>
> I don't think the "default y" is appropriate here, since there are going to
> be lots of ARM64 platforms in the long run that don't have this. Also,
> there is a trend towards using CONFIG_COMPILE_TEST to limit the
> visibility.
>
> I'd suggest something like
>
> config SATA_XGENE
>         tristate "APM X-Gene 6.0Gbps SATA host controller support"
>         depends on ARM64 || COMPILE_TEST
>         ...
>
[Loc Ho]
Okay. How about this?

 depends on ARM64 || COMPILE_TEST
 select SATA_XGENE_PHY && SATA_AHCI_PLATFORM

>> +/* Enable for dumping CSR read/write access */
>> +#undef XGENE_DBG_CSR
>
> This should be removed now as well, along with the debug macro you already removed.
[Loc Ho]
This is very useful if one running into problem - one can enable all
CSR dump. I would like to keep this around for the time being.

>
>> +
>> +/* Temporary function until the PHY parameter API */
>> +extern void xgene_ahci_phy_set_pq(struct phy *phy, int chan, int data);
>> +extern void xgene_ahci_phy_set_spd(struct phy *phy, int chan, int gen);
>
> Ah, that should have been mentioned in the changeset text. Do you think you
> can remove these for the final version?
[Loc Ho]
Yes... Krishon, can you provide an patch that allows me to accommodate
this? Or should I come up one? I will trying to get rip of the first
one. But I will need the function to set the PHY speed - for
Gen2/Gen1. Let's plan on add these function:

a. int (*set_speed)(int gen_speed) where gen_speed is either AUTO,
GEN1, GEN2, or GEN3.
b. Change the PHY init function to take an optional parameter. This
would help my first function in case I can get rip of it.

>
>> +static void xgene_rd(void *addr, u32 *val)
>> +{
>> +     *val = readl(addr);
>> +#if defined(XGENE_DBG_CSR)
>> +     printk(KERN_DEBUG "SATAPHY CSR RD: 0x%p value: 0x%08x\n", addr, *val);
>> +#endif
>> +}
>
> The interface you are looking for is pr_debug() or dev_dbg(), which get
> built-in only if the DEBUG macro is set.
>
> In a lot of cases, it's actually best to remove debug output like this from
> the driver once you have it working  -- whoever is debugging problems in
> the driver next might need completely different debugging information or
> can add them back easily if needed.
>
> It's your choice if you want to use pr_debug() or remove that output
> entirely. If you remove it, best remove the helper functions entirely
> and use readl/writel directly.
[Loc Ho]
I would like to keep this function for now until this driver actual
being used in production. I will use pr_debug.

>
>> +/* Flush the IOB to ensure all SATA controller writes completed before
>> +   servicing the completed command. */
>> +static int xgene_ahci_iob_flush(struct xgene_ahci_context *ctx)
>> +{
>> +     if (ctx->ahbc_io_base == NULL) {
>> +             void *ahbc_base;
>> +             u32 val;
>> +
>> +             /* The AHBC address is fixed in X-Gene */
>> +             ahbc_base = devm_ioremap(ctx->dev, 0x1F2A0000, 0x80000);
>> +             if (!ahbc_base) {
>> +                     dev_err(ctx->dev, "can't map AHBC resource\n");
>> +                     return -ENODEV;
>> +             }
>
> I had an important comment about the misuse of hardcoded I/O addresses
> here. Please never just post a new version with the same issue. In general,
> your options are:
>
> * rewrite the code in a more appropriate way
> * reply to the comment, arguing why you think your code is correct
> * ask for clarification if you don't know how to improve the code
> * mark the code as TODO and mention in the patch description why you
>   are still working on this and that the current version should not
>   be seen as final.
>
> If you don't do any of these, reviewers will get annoyed because you
> are wasting their time.
[Loc Ho]
Sorry about this one. I will add this to the DTS. If this resource
isn't available, then it will be nop.

>> +
>> +static int xgene_ahci_get_u32_param(struct platform_device *pdev,
>> +                                 const char *of_name, char *acpi_name,
>> +                                 u32 *param)
>> +{
>> +#ifdef CONFIG_ACPI
>> +     if (efi_enabled(EFI_BOOT)) {
>> +             unsigned long long value;
>> +             acpi_status status;
>> +             if (acpi_name == NULL)
>> +                     return -ENODEV;
>> +             status = acpi_evaluate_integer(ACPI_HANDLE(&pdev->dev),
>> +                                            acpi_name, NULL, &value);
>> +             if (ACPI_FAILURE(status))
>> +                     return -ENODEV;
>> +             *param = value;
>> +             return 0;
>> +     }
>> +#endif
>
> There are more previous comments that you have not addressed yet.
[Loc Ho]
Original, I didn't want to get rip of this as ACPI isn't available in
the 3.12 kernel yet. I will get rip of this as I don't need the ID any
more. Also, I will also get rip of the clock interface. Don't need
this as it is handled directly by the driver. This will address for DT
as well as ACPI.

>
>> diff --git a/drivers/ata/sata_xgene.h b/drivers/ata/sata_xgene.h
>> new file mode 100644
>> index 0000000..51e73f6
>> --- /dev/null
>> +++ b/drivers/ata/sata_xgene.h
>
> This file should probably just be folded into the driver, since it contains no
> interfaces between  modules, just internal definitions.
[Loc Ho]
I can get rip this header file now. But in the future I may need to
add this back as I intended this driver to also support running from
our co-processor (ARMv7 32-bit). For that, I will need anothe file and
other function that will need knowledge of the context structure and
etc.

-Loc
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Loc Ho Nov. 19, 2013, 9:22 p.m. UTC | #3
Hi Kishon,

>>> +
>>> +/* Temporary function until the PHY parameter API */
>>> +extern void xgene_ahci_phy_set_pq(struct phy *phy, int chan, int data);
>>> +extern void xgene_ahci_phy_set_spd(struct phy *phy, int chan, int gen);
>>
>> Ah, that should have been mentioned in the changeset text. Do you think you
>> can remove these for the final version?
> [Loc Ho]
> Yes... Krishon, can you provide an patch that allows me to accommodate
> this? Or should I come up one? I will trying to get rip of the first
> one. But I will need the function to set the PHY speed - for
> Gen2/Gen1. Let's plan on add these function:
>
> a. int (*set_speed)(int gen_speed) where gen_speed is either AUTO,
> GEN1, GEN2, or GEN3.
> b. Change the PHY init function to take an optional parameter. This
> would help my first function in case I can get rip of it.
>
[Loc Ho]
I will provide this patch as part of my next version to include an
function as follow:

int set_speed(struct *phy, int lane, u64 speed);

where lane indicates the lane of the PHY and speed is the PHY speed in hertz.

-Loc
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Arnd Bergmann Nov. 21, 2013, 1:20 p.m. UTC | #4
On Saturday 16 November 2013, Loc Ho wrote:


> >
> > config SATA_XGENE
> >         tristate "APM X-Gene 6.0Gbps SATA host controller support"
> >         depends on ARM64 || COMPILE_TEST
> >         ...
> >
> [Loc Ho]
> Okay. How about this?
> 
>  depends on ARM64 || COMPILE_TEST
>  select SATA_XGENE_PHY && SATA_AHCI_PLATFORM

I think you already found the mistake withis and corrected this in v4.

> > The interface you are looking for is pr_debug() or dev_dbg(), which get
> > built-in only if the DEBUG macro is set.
> >
> > In a lot of cases, it's actually best to remove debug output like this from
> > the driver once you have it working  -- whoever is debugging problems in
> > the driver next might need completely different debugging information or
> > can add them back easily if needed.
> >
> > It's your choice if you want to use pr_debug() or remove that output
> > entirely. If you remove it, best remove the helper functions entirely
> > and use readl/writel directly.
> [Loc Ho]
> I would like to keep this function for now until this driver actual
> being used in production. I will use pr_debug.

Ok.

> >> diff --git a/drivers/ata/sata_xgene.h b/drivers/ata/sata_xgene.h
> >> new file mode 100644
> >> index 0000000..51e73f6
> >> --- /dev/null
> >> +++ b/drivers/ata/sata_xgene.h
> >
> > This file should probably just be folded into the driver, since it contains no
> > interfaces between  modules, just internal definitions.
> [Loc Ho]
> I can get rip this header file now. But in the future I may need to
> add this back as I intended this driver to also support running from
> our co-processor (ARMv7 32-bit). For that, I will need anothe file and
> other function that will need knowledge of the context structure and
> etc.

Hmm, is the code for that coprocessor compiled from the kernel source?
If not, it shouldn't really make a difference as it won't live in a shared
code repository.

	Arnd
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Loc Ho Nov. 21, 2013, 7:01 p.m. UTC | #5
Hi,

>> >> diff --git a/drivers/ata/sata_xgene.h b/drivers/ata/sata_xgene.h
>> >> new file mode 100644
>> >> index 0000000..51e73f6
>> >> --- /dev/null
>> >> +++ b/drivers/ata/sata_xgene.h
>> >
>> > This file should probably just be folded into the driver, since it contains no
>> > interfaces between  modules, just internal definitions.
>> [Loc Ho]
>> I can get rip this header file now. But in the future I may need to
>> add this back as I intended this driver to also support running from
>> our co-processor (ARMv7 32-bit). For that, I will need anothe file and
>> other function that will need knowledge of the context structure and
>> etc.
>
> Hmm, is the code for that coprocessor compiled from the kernel source?
> If not, it shouldn't really make a difference as it won't live in a shared
> code repository.
>
[Loc Ho]
The co-processors are just ARM based core and the same kernel can be
build to support it. Let's not worry about this yet.

-Loc
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Kishon Vijay Abraham I Nov. 26, 2013, 10:11 a.m. UTC | #6
Hi,

On Wednesday 20 November 2013 02:52 AM, Loc Ho wrote:
> Hi Kishon,
> 
>>>> +
>>>> +/* Temporary function until the PHY parameter API */
>>>> +extern void xgene_ahci_phy_set_pq(struct phy *phy, int chan, int data);
>>>> +extern void xgene_ahci_phy_set_spd(struct phy *phy, int chan, int gen);
>>>
>>> Ah, that should have been mentioned in the changeset text. Do you think you
>>> can remove these for the final version?
>> [Loc Ho]
>> Yes... Krishon, can you provide an patch that allows me to accommodate
>> this? Or should I come up one? I will trying to get rip of the first
>> one. But I will need the function to set the PHY speed - for
>> Gen2/Gen1. Let's plan on add these function:
>>
>> a. int (*set_speed)(int gen_speed) where gen_speed is either AUTO,
>> GEN1, GEN2, or GEN3.
>> b. Change the PHY init function to take an optional parameter. This
>> would help my first function in case I can get rip of it.
>>
> [Loc Ho]
> I will provide this patch as part of my next version to include an
> function as follow:

sure..
> 
> int set_speed(struct *phy, int lane, u64 speed);

it should be phy_set_speed.
> 
> where lane indicates the lane of the PHY and speed is the PHY speed in hertz.

Does lane here means the number of lanes? Is the lane also obtained after the
training sequence?

Thanks
Kishon
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Loc Ho Nov. 26, 2013, 4:41 p.m. UTC | #7
Hi,

>> int set_speed(struct *phy, int lane, u64 speed);
>
> it should be phy_set_speed.
[Loc Ho]
But your other functions don't repeat the prefix "phy"?

>>
>> where lane indicates the lane of the PHY and speed is the PHY speed in hertz.
>
> Does lane here means the number of lanes? Is the lane also obtained after the
> training sequence?
[Loc Ho]
Lane here is the lane with you are changing the speed. If there are
two lanes, then 0 parameter would change lane 0. 1 would change lane
1.

-Loc
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Kishon Vijay Abraham I Nov. 27, 2013, 5:52 a.m. UTC | #8
On Tuesday 26 November 2013 10:11 PM, Loc Ho wrote:
> Hi,
> 
>>> int set_speed(struct *phy, int lane, u64 speed);
>>
>> it should be phy_set_speed.
> [Loc Ho]
> But your other functions don't repeat the prefix "phy"?

refer include/linux/phy/phy.h..

int phy_init(struct phy *phy);
int phy_exit(struct phy *phy);
int phy_power_on(struct phy *phy);
int phy_power_off(struct phy *phy);

??

> 
>>>
>>> where lane indicates the lane of the PHY and speed is the PHY speed in hertz.
>>
>> Does lane here means the number of lanes? Is the lane also obtained after the
>> training sequence?
> [Loc Ho]
> Lane here is the lane with you are changing the speed. If there are
> two lanes, then 0 parameter would change lane 0. 1 would change lane
> 1.

can different lanes operate at different speed at the same time?

Thanks
Kishon
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Loc Ho Nov. 27, 2013, 5:58 a.m. UTC | #9
Hi,

>>>> int set_speed(struct *phy, int lane, u64 speed);
>>>
>>> it should be phy_set_speed.
>> [Loc Ho]
>> But your other functions don't repeat the prefix "phy"?
>
> refer include/linux/phy/phy.h..
>
> int phy_init(struct phy *phy);
> int phy_exit(struct phy *phy);
> int phy_power_on(struct phy *phy);
> int phy_power_off(struct phy *phy);
[Loc Ho]
For the top level function, it is phy_set_speed. For the operation
function pointer, it is set_speed.

>>>>
>>>> where lane indicates the lane of the PHY and speed is the PHY speed in hertz.
>>>
>>> Does lane here means the number of lanes? Is the lane also obtained after the
>>> training sequence?
>> [Loc Ho]
>> Lane here is the lane with you are changing the speed. If there are
>> two lanes, then 0 parameter would change lane 0. 1 would change lane
>> 1.
>
> can different lanes operate at different speed at the same time?
>
[Loc Ho]
Yes. Each lane is suppose to be independent of each other.

-Loc
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diff mbox

Patch

diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index d467e06..60da4a2 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -112,6 +112,14 @@  config SATA_XGENE_PHY
 	help
 	  This option enables support for APM X-Gene SoC SATA PHY.
 
+config SATA_XGENE
+	tristate "APM X-Gene 6.0Gbps SATA host controller support"
+	depends on SATA_AHCI_PLATFORM
+	default y if ARM64
+	select SATA_XGENE_PHY
+	help
+	  This option enables support for APM X-Gene SoC SATA host controller.
+
 config SATA_FSL
 	tristate "Freescale 3.0Gbps SATA support"
 	depends on FSL_SOC
diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
index be53890..f141566 100644
--- a/drivers/ata/Makefile
+++ b/drivers/ata/Makefile
@@ -12,6 +12,7 @@  obj-$(CONFIG_SATA_DWC)		+= sata_dwc_460ex.o
 obj-$(CONFIG_SATA_HIGHBANK)	+= sata_highbank.o libahci.o
 obj-$(CONFIG_AHCI_IMX)		+= ahci_imx.o
 obj-$(CONFIG_SATA_XGENE_PHY)	+= sata_xgene_phy.o
+obj-$(CONFIG_SATA_XGENE)	+= sata_xgene.o
 
 # SFF w/ custom DMA
 obj-$(CONFIG_PDC_ADMA)		+= pdc_adma.o
diff --git a/drivers/ata/sata_xgene.c b/drivers/ata/sata_xgene.c
new file mode 100644
index 0000000..88bcc34
--- /dev/null
+++ b/drivers/ata/sata_xgene.c
@@ -0,0 +1,1271 @@ 
+/*
+ * AppliedMicro X-Gene SoC SATA Driver
+ *
+ * Copyright (c) 2013, Applied Micro Circuits Corporation
+ * Author: Loc Ho <lho@apm.com>
+ *         Tuan Phan <tphan@apm.com>
+ *         Suman Tripathi <stripathi@apm.com>
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/acpi.h>
+#include <linux/efi.h>
+#include <linux/phy/phy.h>
+#include "sata_xgene.h"
+
+/* Enable for dumping CSR read/write access */
+#undef XGENE_DBG_CSR
+
+/* Max # of disk per a controller */
+#define MAX_AHCI_CHN_PERCTR		2
+
+#define SATA_DIAG_OFFSET		0x0000D000
+#define SATA_GLB_OFFSET			0x0000D850
+#define SATA_SHIM_OFFSET		0x0000E000
+#define SATA_MASTER_OFFSET		0x0000F000
+#define SATA_PORT0_OFFSET		0x00000100
+#define SATA_PORT1_OFFSET		0x00000180
+
+/* SATA host controller CSR */
+#define SLVRDERRATTRIBUTES_ADDR		0x00000000
+#define SLVWRERRATTRIBUTES_ADDR		0x00000004
+#define MSTRDERRATTRIBUTES_ADDR		0x00000008
+#define MSTWRERRATTRIBUTES_ADDR		0x0000000c
+#define BUSCTLREG_ADDR			0x00000014
+#define  MSTAWAUX_COHERENT_BYPASS_SET(dst, src) \
+		(((dst) & ~0x00000002) | (((u32)(src)<<1) & 0x00000002))
+#define  MSTARAUX_COHERENT_BYPASS_SET(dst, src) \
+		(((dst) & ~0x00000001) | (((u32)(src)) & 0x00000001))
+#define IOFMSTRWAUX_ADDR		0x00000018
+#define INTSTATUSMASK_ADDR		0x0000002c
+#define ERRINTSTATUS_ADDR		0x00000030
+#define ERRINTSTATUSMASK_ADDR		0x00000034
+
+/* SATA host AHCI CSR */
+#define PORTCFG_ADDR			0x000000a4
+#define  PORTADDR_SET(dst, src) \
+		(((dst) & ~0x0000003f) | (((u32)(src)) & 0x0000003f))
+#define PORTPHY1CFG_ADDR		0x000000a8
+#define PORTPHY1CFG_FRCPHYRDY_SET(dst, src) \
+		(((dst) & ~0x00100000) | (((u32)(src) << 0x14) & 0x00100000))
+#define PORTPHY2CFG_ADDR		0x000000ac
+#define PORTPHY3CFG_ADDR		0x000000b0
+#define PORTPHY4CFG_ADDR		0x000000b4
+#define PORTPHY5CFG_ADDR		0x000000b8
+#define SCTL0_ADDR			0x0000012C
+#define PORTPHY5CFG_RTCHG_SET(dst, src) \
+		(((dst) & ~0xfff00000) | (((u32)(src) << 0x14) & 0xfff00000))
+#define PORTAXICFG_EN_CONTEXT_SET(dst, src) \
+		(((dst) & ~0x01000000) | (((u32)(src) << 0x18) & 0x01000000))
+#define PORTAXICFG_ADDR			0x000000bc
+#define PORTAXICFG_OUTTRANS_SET(dst, src) \
+		(((dst) & ~0x00f00000) | (((u32)(src) << 0x14) & 0x00f00000))
+
+/* SATA host controller slave CSR */
+#define INT_SLV_TMOMASK_ADDR		0x00000010
+
+/* SATA global diagnostic CSR */
+#define REGSPEC_CFG_MEM_RAM_SHUTDOWN_ADDR	0x00000070
+#define REGSPEC_BLOCK_MEM_RDY_ADDR		0x00000074
+
+/* AHBC IOB flush CSR */
+#define CFG_AMA_MODE_ADDR		0x0000e014
+#define  CFG_RD2WR_EN			0x00000002
+
+#define MAX_RETRY_COUNT			3
+#define SATA_RESET_MEM_RAM_TO		100000
+
+/* Temporary function until the PHY parameter API */
+extern void xgene_ahci_phy_set_pq(struct phy *phy, int chan, int data);
+extern void xgene_ahci_phy_set_spd(struct phy *phy, int chan, int gen);
+
+static void xgene_rd(void *addr, u32 *val)
+{
+	*val = readl(addr);
+#if defined(XGENE_DBG_CSR)
+	printk(KERN_DEBUG "SATAPHY CSR RD: 0x%p value: 0x%08x\n", addr, *val);
+#endif
+}
+
+static void xgene_wr(void *addr, u32 val)
+{
+	writel(val, addr);
+#if defined(XGENE_DBG_CSR)
+	printk(KERN_DEBUG "SATAPHY CSR WR: 0x%p value: 0x%08x\n", addr, val);
+#endif
+}
+
+static void xgene_wr_flush(void *addr, u32 val)
+{
+	writel(val, addr);
+#if defined(XGENE_DBG_CSR)
+	printk(KERN_DEBUG "SATAPHY CSR WR: 0x%p value: 0x%08x\n", addr, val);
+#endif
+	val = readl(addr);
+}
+
+static int xgene_ahci_get_channel(struct ata_host *host, struct ata_port *port)
+{
+	int i;
+	for (i = 0; i < host->n_ports; i++)
+		if (host->ports[i] == port)
+			return i;
+	return -1;
+}
+
+int xgene_ahci_init_memram(struct xgene_ahci_context *ctx)
+{
+	void *diagcsr = ctx->csr_base + SATA_DIAG_OFFSET;
+	int timeout;
+	u32 val;
+
+	xgene_rd(diagcsr + REGSPEC_CFG_MEM_RAM_SHUTDOWN_ADDR, &val);
+	if (val == 0) {
+		dev_dbg(ctx->dev, "already clear memory shutdown\n");
+		return 0;
+	}
+	dev_dbg(ctx->dev, "clear controller %d memory shutdown\n", ctx->cid);
+	/* SATA controller memory in shutdown. Remove from shutdown. */
+	xgene_wr_flush(diagcsr + REGSPEC_CFG_MEM_RAM_SHUTDOWN_ADDR, 0x00);
+	timeout = SATA_RESET_MEM_RAM_TO;
+	do {
+		xgene_rd(diagcsr + REGSPEC_BLOCK_MEM_RDY_ADDR, &val);
+		if (val != 0xFFFFFFFF)
+			udelay(1);
+	} while (val != 0xFFFFFFFF && timeout-- > 0);
+	if (timeout <= 0) {
+		dev_err(ctx->dev, "failed to remove memory from shutdown\n");
+		return -ENODEV;
+	}
+	return 0;
+}
+
+/*
+ * Custom Query ID command
+ *
+ * Due to HW errata, we must stop and re-start the port state machine after
+ * read ID command.
+ */
+static unsigned int xgene_ahci_read_id(struct ata_device *dev,
+				       struct ata_taskfile *tf, u16 *id)
+{
+	u32 err_mask;
+	struct ata_port *ap = dev->link->ap;
+	void *port_mmio = ahci_port_base(ap);
+	u32 data32;
+
+	err_mask = ata_do_dev_read_id(dev, tf, id);
+	if (err_mask)
+		return err_mask;
+
+	/* Mask reserved area. Bit78 spec of Link Power Management
+	 * bit15-8: reserved
+	 * bit7: NCQ autosence
+	 * bit6: Software settings preservation supported
+	 * bit5: reserved
+	 * bit4: In-order sata delivery supported
+	 * bit3: DIPM requests supported
+	 * bit2: DMA Setup FIS Auto-Activate optimization supported
+	 * bit1: DMA Setup FIX non-Zero buffer offsets supported
+	 * bit0: Reserved
+	 *
+	 * Clear reserved bit (DEVSLP bit) as we don't support DEVSLP
+	 */
+	id[78] &= 0x00FF;
+
+	/* Restart the port if requred due to HW errata */
+	data32 = readl(port_mmio + PORT_CMD_ISSUE);
+	if (data32 == 0x00000000) {
+		writel(PORT_CMD_FIS_RX, port_mmio + PORT_CMD);
+		readl(port_mmio + PORT_CMD);	/* flush */
+		writel(PORT_CMD_FIS_RX | PORT_CMD_START, port_mmio + PORT_CMD);
+		readl(port_mmio + PORT_CMD);	/* flush */
+	}
+	return 0;
+}
+
+static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	struct ahci_port_priv *pp = ap->private_data;
+
+	/* Keep track of the currently active link.  It will be used
+	 * in completion path to determine whether NCQ phase is in
+	 * progress.
+	 */
+	pp->active_link = qc->dev->link;
+
+	if (qc->tf.protocol == ATA_PROT_NCQ)
+		writel(1 << qc->tag, port_mmio + PORT_SCR_ACT);
+
+	if (pp->fbs_enabled && pp->fbs_last_dev != qc->dev->link->pmp) {
+		u32 fbs = readl(port_mmio + PORT_FBS);
+		fbs &= ~(PORT_FBS_DEV_MASK | PORT_FBS_DEC);
+		fbs |= qc->dev->link->pmp << PORT_FBS_DEV_OFFSET;
+		writel(fbs, port_mmio + PORT_FBS);
+		pp->fbs_last_dev = qc->dev->link->pmp;
+	}
+
+	writel(1 << qc->tag, port_mmio + PORT_CMD_ISSUE);
+
+	ahci_sw_activity(qc->dev->link);
+
+	/* For query ID command, restart the port if requred due to HW errata.
+	   This is needed when PMP is attached. */
+	if (qc->dev->link->pmp && qc->tf.command == ATA_CMD_ID_ATA &&
+	    readl(port_mmio + PORT_CMD_ISSUE) == 0x0) {
+		writel(PORT_CMD_FIS_RX, port_mmio + PORT_CMD);
+		readl(port_mmio + PORT_CMD);	/* flush */
+		writel(PORT_CMD_FIS_RX | PORT_CMD_START, port_mmio + PORT_CMD);
+		readl(port_mmio + PORT_CMD);	/* flush */
+	}
+
+	return 0;
+}
+
+static void xgene_ahci_enable_phy(struct xgene_ahci_context *ctx,
+				  int channel, int enable)
+{
+	void *mmio = ctx->mmio_base;
+	u32 val;
+
+	xgene_rd(mmio + PORTCFG_ADDR, &val);
+	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
+	xgene_wr_flush(mmio + PORTCFG_ADDR, val);
+	xgene_rd(mmio + PORTPHY1CFG_ADDR, &val);
+	val = PORTPHY1CFG_FRCPHYRDY_SET(val, enable);
+	xgene_wr(mmio + PORTPHY1CFG_ADDR, val);
+}
+
+static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel)
+{
+	void *mmio = ctx->mmio_base;
+	u32 val;
+
+	dev_dbg(ctx->dev, "SATA%d.%d port configure mmio 0x%p channel %d\n",
+		ctx->cid, channel, mmio, channel);
+	xgene_rd(mmio + PORTCFG_ADDR, &val);
+	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
+	xgene_wr_flush(mmio + PORTCFG_ADDR, val);
+	/* Disable fix rate */
+	xgene_wr_flush(mmio + PORTPHY1CFG_ADDR, 0x0001fffe);
+	xgene_wr_flush(mmio + PORTPHY2CFG_ADDR, 0x5018461c);
+	xgene_wr_flush(mmio + PORTPHY3CFG_ADDR, 0x1c081907);
+	xgene_wr_flush(mmio + PORTPHY4CFG_ADDR, 0x1c080815);
+	xgene_rd(mmio + PORTPHY5CFG_ADDR, &val);
+	/* Window negotiation 0x800 to 0x400 */
+	val = PORTPHY5CFG_RTCHG_SET(val, 0x300);
+	xgene_wr_flush(mmio + PORTPHY5CFG_ADDR, val);
+	xgene_rd(mmio + PORTAXICFG_ADDR, &val);
+	val = PORTAXICFG_EN_CONTEXT_SET(val, 0x1); /* enable context mgmt */
+	val = PORTAXICFG_OUTTRANS_SET(val, 0xe); /* Outstanding */
+	xgene_wr_flush(mmio + PORTAXICFG_ADDR, val);
+}
+
+/* Restart the PHY in case of disparity error for Gen2/Gen1 disk only */
+static int xgene_ahci_phy_restart(struct ata_link *link)
+{
+	struct ata_port *port = link->ap;
+	struct ata_host *host = port->host;
+	struct xgene_ahci_context *ctx = host->private_data;
+	int channel;
+
+	channel = xgene_ahci_get_channel(host, port);
+	if (channel < 0 || channel >= MAX_AHCI_CHN_PERCTR)
+		return -EINVAL;
+	xgene_ahci_enable_phy(ctx, channel, 1);
+	xgene_ahci_enable_phy(ctx, channel, 0);
+	return 0;
+}
+
+static int xgene_ahci_do_hardreset(struct ata_link *link, int chan,
+				   unsigned long deadline, bool *online)
+{
+	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
+	struct ata_port *ap = link->ap;
+	struct xgene_ahci_context *ctx = ap->host->private_data;
+	struct ahci_port_priv *pp = ap->private_data;
+	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	struct ata_taskfile tf;
+	int link_retry = 0;
+	int retry = 0;
+	int rc;
+	u32 val;
+
+hardreset_retry:
+	/* clear D2H reception area to properly wait for D2H FIS */
+	ata_tf_init(link->device, &tf);
+	tf.command = 0x80;
+	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
+	xgene_ahci_phy_set_pq(ctx->phy, chan, 1);
+	rc = sata_link_hardreset(link, timing, deadline, online,
+				 ahci_check_ready);
+	xgene_ahci_phy_set_pq(ctx->phy, chan, 0);
+	/* clear all errors */
+	xgene_rd(port_mmio + PORT_SCR_ERR, &val);
+	xgene_wr(port_mmio + PORT_SCR_ERR, val);
+
+	/* Check to ensure that the disk comes up in match speed */
+	if (*online) {
+		u32 sstatus;
+		sata_scr_read(link, SCR_STATUS, &sstatus);
+		if (!retry) {
+			if (((sstatus >> 4) & 0xf) == 2) {
+				/* For Gen2 and first time, let's check again
+				 * with Gen2 serdes to ensure actual Gen2 disk.
+				 */
+				xgene_ahci_phy_set_spd(ctx->phy, chan, 2);
+				xgene_ahci_phy_restart(link);
+				++retry;
+				goto hardreset_retry;
+			} else if (((sstatus >> 4) & 0xf) == 1) {
+				/* For Gen1 and first time, let's check again
+				 * with Gen1 serdes to ensure actual Gen1 disk.
+				 */
+				xgene_ahci_phy_set_spd(ctx->phy, chan, 1);
+				xgene_ahci_phy_restart(link);
+				++retry;
+				goto hardreset_retry;
+			}
+		}
+	} else if (link_retry < 4) {
+		link_retry++;
+		goto hardreset_retry;
+	}
+	ata_link_dbg(link, "SATA%d.%d post-hardrest PORT_CMD 0x%08X\n",
+		     ctx->cid, chan, readl(port_mmio + PORT_CMD));
+
+	return rc;
+}
+
+static int xgene_ahci_hardreset(struct ata_link *link, unsigned int *class,
+				unsigned long deadline)
+{
+	struct ata_port *ap = link->ap;
+	struct xgene_ahci_context *ctx = ap->host->private_data;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	bool online;
+	int chan;
+	int rc;
+	int portcmd_saved;
+	u32 portclb_saved;
+	u32 portclbhi_saved;
+	u32 portrxfis_saved;
+	u32 portrxfishi_saved;
+
+	chan = xgene_ahci_get_channel(ap->host, ap);
+	if (chan >= MAX_AHCI_CHN_PERCTR) {
+		*class = ATA_DEV_NONE;
+		return 0;
+	}
+	ata_link_dbg(link, "SATA%d.%d APM hardreset\n", ctx->cid, chan);
+
+	/* As hardreset reset these CSR, let save it to restore later */
+	portcmd_saved = readl(port_mmio + PORT_CMD);
+	portclb_saved = readl(port_mmio + PORT_LST_ADDR);
+	portclbhi_saved = readl(port_mmio + PORT_LST_ADDR_HI);
+	portrxfis_saved = readl(port_mmio + PORT_FIS_ADDR);
+	portrxfishi_saved = readl(port_mmio + PORT_FIS_ADDR_HI);
+	ata_link_dbg(link, "SATA%d.%d PORT_CMD 0x%08X\n", ctx->cid, chan,
+		     portcmd_saved);
+
+	ahci_stop_engine(ap);
+
+#if 0
+hardreset_retry:
+	/* clear D2H reception area to properly wait for D2H FIS */
+	ata_tf_init(link->device, &tf);
+	tf.command = 0x80;
+	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
+	xgene_ahci_phy_set_pq(ctx->phy, channel, 1);
+	rc = sata_link_hardreset(link, timing, deadline, &online,
+				 ahci_check_ready);
+	xgene_ahci_phy_set_pq(ctx->phy, channel, 0);
+	/* clear all errors */
+	xgene_rd(port_mmio + PORT_SCR_ERR, &val);
+	xgene_wr(port_mmio + PORT_SCR_ERR, val);
+
+	/* Check to ensure that the disk comes up in match speed */
+	if (online) {
+		sata_scr_read(link, SCR_STATUS, &sstatus);
+		if (!retry) {
+			if (((sstatus >> 4) & 0xf) == 2) {
+				/* For Gen2 and first time, let's check again
+				 * with Gen2 serdes to ensure actual Gen2 disk.
+				 */
+				xgene_ahci_phy_set_spd(ctx->phy, channel, 2);
+				xgene_ahci_phy_restart(link);
+				++retry;
+				goto hardreset_retry;
+			} else if (((sstatus >> 4) & 0xf) == 1) {
+				/* For Gen1 and first time, let's check again
+				 * with Gen1 serdes to ensure actual Gen1 disk.
+				 */
+				xgene_ahci_phy_set_spd(ctx->phy, channel, 1);
+				xgene_ahci_phy_restart(link);
+				++retry;
+				goto hardreset_retry;
+			}
+		}
+	} else if (link_retry < 4) {
+		link_retry++;
+		goto hardreset_retry;
+	}
+	ata_link_dbg(link, "SATA%d.%d post-hardrest PORT_CMD 0x%08X\n",
+		     ctx->cid, channel, readl(port_mmio + PORT_CMD));
+#else
+	rc = xgene_ahci_do_hardreset(link, chan, deadline, &online);
+#endif
+
+	/* As controller hardreset clear them, let restore them */
+	writel(portcmd_saved, port_mmio + PORT_CMD);
+	writel(portclb_saved, port_mmio + PORT_LST_ADDR);
+	writel(portclbhi_saved, port_mmio + PORT_LST_ADDR_HI);
+	writel(portrxfis_saved, port_mmio + PORT_FIS_ADDR);
+	writel(portrxfishi_saved, port_mmio + PORT_FIS_ADDR_HI);
+	ata_link_dbg(link, "SATA%d.%d restore PORT_CMD 0x%08X\n",
+		     ctx->cid, chan, readl(port_mmio + PORT_CMD));
+
+	ahci_start_engine(ap);
+
+	if (online)
+		*class = ahci_dev_classify(ap);
+
+	ata_link_dbg(link, "SATA%d.%d APM hardreset EXIT class %u\n",
+		     ctx->cid, chan, *class);
+	return 0;
+}
+
+/* Flush the IOB to ensure all SATA controller writes completed before
+   servicing the completed command. */
+static int xgene_ahci_iob_flush(struct xgene_ahci_context *ctx)
+{
+	if (ctx->ahbc_io_base == NULL) {
+		void *ahbc_base;
+		u32 val;
+
+		/* The AHBC address is fixed in X-Gene */
+		ahbc_base = devm_ioremap(ctx->dev, 0x1F2A0000, 0x80000);
+		if (!ahbc_base) {
+			dev_err(ctx->dev, "can't map AHBC resource\n");
+			return -ENODEV;
+		}
+		/* The read to flush addres is fixed in X-Gene */
+		ctx->ahbc_io_base = devm_ioremap(ctx->dev, 0x1C000200, 0x100);
+		if (!ctx->ahbc_io_base) {
+			devm_iounmap(ctx->dev, ahbc_base);
+			dev_err(ctx->dev, "can't map AHBC IO resource\n");
+			return -ENODEV;
+		}
+		/* Enable IOB flush feature */
+		val = readl(ahbc_base + CFG_AMA_MODE_ADDR);
+		val |= CFG_RD2WR_EN;
+		writel(val, ahbc_base + CFG_AMA_MODE_ADDR);
+		devm_iounmap(ctx->dev, ahbc_base);
+	}
+	readl(ctx->ahbc_io_base);
+	return 0;
+}
+
+static unsigned int xgene_ahci_fill_sg(struct ata_queued_cmd *qc, void *cmd_tbl)
+{
+	struct scatterlist *sg;
+	struct ahci_sg *ahci_sg = cmd_tbl + AHCI_CMD_TBL_HDR_SZ;
+	unsigned int si;
+
+	/*
+	 * Next, the S/G list.
+	 */
+	for_each_sg(qc->sg, sg, qc->n_elem, si) {
+		dma_addr_t addr = sg_dma_address(sg);
+		u64 dma_addr = xgene_ahci_to_axi(addr);
+		u32 sg_len = sg_dma_len(sg);
+		ahci_sg[si].addr = cpu_to_le32(dma_addr & 0xffffffff);
+		ahci_sg[si].addr_hi = cpu_to_le32((dma_addr >> 16) >> 16);
+		ahci_sg[si].flags_size = cpu_to_le32(sg_len - 1);
+		xgene_ahci_dflush((void *) __va(addr), sg_len);
+	}
+	return si;
+}
+
+static void xgene_ahci_qc_prep(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	struct ahci_port_priv *pp = ap->private_data;
+	int is_atapi = ata_is_atapi(qc->tf.protocol);
+	void *cmd_tbl;
+	u32 opts;
+	const u32 cmd_fis_len = 5;	/* five dwords */
+	unsigned int n_elem;
+	void *port_mmio = ahci_port_base(ap);
+	u32 fbs;
+
+	/*
+	 * Fill in command table information.  First, the header,
+	 * a SATA Register - Host to Device command FIS.
+	 */
+	cmd_tbl = pp->cmd_tbl + qc->tag * AHCI_CMD_TBL_SZ;
+
+	/* Due to hardware errata for port multipier CBS mode, enable DEV
+	   field of PxFBS in order to clear the PxCI */
+	if (qc->dev->link->pmp) {
+		fbs = readl(port_mmio + 0x40);
+		if ((fbs >> 8) & 0x0000000f) {
+			fbs &= 0xfffff0ff;
+			fbs |= qc->dev->link->pmp << 8;
+			writel(fbs, port_mmio + 0x40);
+		}
+	}
+
+	ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, cmd_tbl);
+	if (is_atapi) {
+		memset(cmd_tbl + AHCI_CMD_TBL_CDB, 0, 32);
+		memcpy(cmd_tbl + AHCI_CMD_TBL_CDB, qc->cdb, qc->dev->cdb_len);
+	}
+	n_elem = 0;
+	if (qc->flags & ATA_QCFLAG_DMAMAP)
+		n_elem = xgene_ahci_fill_sg(qc, cmd_tbl);
+
+	/*
+	 * Fill in command slot information.
+	 */
+	opts = cmd_fis_len | n_elem << 16 | (qc->dev->link->pmp << 12);
+	if (qc->tf.flags & ATA_TFLAG_WRITE)
+		opts |= AHCI_CMD_WRITE;
+	if (is_atapi)
+		opts |= AHCI_CMD_ATAPI | AHCI_CMD_PREFETCH;
+
+	xgene_ahci_fill_cmd_slot(pp, qc->tag, opts);
+}
+
+/* Due to HW BUG we are limited to single FIS receive area for FBS
+ * so limiting the FBS FIS area from 16 to 0
+ */
+static bool xgene_ahci_qc_fill_rtf(struct ata_queued_cmd *qc)
+{
+	struct ahci_port_priv *pp = qc->ap->private_data;
+	u8 *rx_fis = pp->rx_fis;
+
+	/*
+	 * After a successful execution of an ATA PIO data-in command,
+	 * the device doesn't send D2H Reg FIS to update the TF and
+	 * the host should take TF and E_Status from the preceding PIO
+	 * Setup FIS.
+	 */
+	if (qc->tf.protocol == ATA_PROT_PIO && qc->dma_dir == DMA_FROM_DEVICE &&
+	    !(qc->flags & ATA_QCFLAG_FAILED)) {
+		ata_tf_from_fis(rx_fis + RX_FIS_PIO_SETUP, &qc->result_tf);
+		qc->result_tf.command = (rx_fis + RX_FIS_PIO_SETUP)[15];
+	} else
+		ata_tf_from_fis(rx_fis + RX_FIS_D2H_REG, &qc->result_tf);
+
+	return true;
+}
+
+static int xgene_ahci_do_softreset(struct ata_link *link,
+				   unsigned int *class, int pmp,
+				   unsigned long deadline,
+				   int (*check_ready) (struct ata_link *link))
+{
+	struct ata_port *ap = link->ap;
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+	const char *reason = NULL;
+	unsigned long now, msecs;
+	struct ata_taskfile tf;
+	int rc;
+
+	ata_link_dbg(link, "ENTER\n");
+
+	/* prepare for SRST (AHCI-1.1 10.4.1) */
+	rc = ahci_kick_engine(ap);
+	if (rc && rc != -EOPNOTSUPP)
+		ata_link_warn(link, "failed to reset engine (errno=%d)\n", rc);
+
+	ata_tf_init(link->device, &tf);
+	/* issue the first D2H Register FIS */
+	msecs = 0;
+	now = jiffies;
+	if (time_after(deadline, now))
+		msecs = jiffies_to_msecs(deadline - now);
+
+	tf.ctl |= ATA_SRST;
+	/* Must call X-Gene version in case it needs to flush the cache for
+	   MSLIM as well as AXI address translation */
+	if (xgene_ahci_exec_polled_cmd(ap, pmp, &tf, 0,
+				       AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY,
+				       msecs)) {
+		rc = -EIO;
+		reason = "1st FIS failed";
+		goto fail;
+	}
+
+	/* spec says at least 5us, but be generous and sleep for 1ms */
+	ata_msleep(ap, 1);
+
+	/* issue the second D2H Register FIS */
+	tf.ctl &= ~ATA_SRST;
+	/* HW need AHCI_CMD_RESET and AHCI_CMD_CLR_BUSY */
+	xgene_ahci_exec_polled_cmd(ap, pmp, &tf, 0,
+				   AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY, msecs);
+	/* wait for link to become ready */
+	rc = ata_wait_after_reset(link, deadline, check_ready);
+	if (rc == -EBUSY && hpriv->flags & AHCI_HFLAG_SRST_TOUT_IS_OFFLINE) {
+		/*
+		 * Workaround for cases where link online status can't
+		 * be trusted.  Treat device readiness timeout as link
+		 * offline.
+		 */
+		ata_link_info(link, "device not ready, treating as offline\n");
+		*class = ATA_DEV_NONE;
+	} else if (rc) {
+		/* link occupied, -ENODEV too is an error */
+		reason = "device not ready";
+		goto fail;
+	} else {
+		*class = ahci_dev_classify(ap);
+	}
+
+	ata_link_dbg(link, "EXIT, class=%u\n", *class);
+	return 0;
+
+fail:
+	ata_link_err(link, "softreset failed (%s)\n", reason);
+	return rc;
+}
+
+static int xgene_ahci_softreset(struct ata_link *link, unsigned int *class,
+				unsigned long deadline)
+{
+	int pmp = sata_srst_pmp(link);
+	return xgene_ahci_do_softreset(link, class, pmp, deadline,
+				       ahci_check_ready);
+}
+
+static struct ata_port_operations xgene_ahci_ops = {
+	.inherits = &ahci_ops,
+	.hardreset = xgene_ahci_hardreset,
+	.read_id = xgene_ahci_read_id,
+	.qc_prep = xgene_ahci_qc_prep,
+	.qc_issue = xgene_ahci_qc_issue,
+	.softreset = xgene_ahci_softreset,
+	.pmp_softreset = xgene_ahci_softreset,
+	.qc_fill_rtf = xgene_ahci_qc_fill_rtf,
+};
+
+static const struct ata_port_info xgene_ahci_port_info[] = {
+	{
+	 .flags = AHCI_FLAG_COMMON,
+	 .pio_mask = ATA_PIO4,
+	 .udma_mask = ATA_UDMA6,
+	 .port_ops = &xgene_ahci_ops,
+	 },
+};
+
+static struct scsi_host_template xgene_ahci_sht = {
+	AHCI_SHT("XGene-ahci"),
+};
+
+static void xgene_ahci_port_intr(struct ata_port *ap)
+{
+	void __iomem *port_mmio = ahci_port_base(ap);
+	struct ata_eh_info *ehi = &ap->link.eh_info;
+	struct ahci_port_priv *pp = ap->private_data;
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+	int resetting = !!(ap->pflags & ATA_PFLAG_RESETTING);
+	u32 status, qc_active = 0;
+	int rc;
+
+	status = readl(port_mmio + PORT_IRQ_STAT);
+	writel(status, port_mmio + PORT_IRQ_STAT);
+
+	/* ignore BAD_PMP while resetting */
+	if (unlikely(resetting))
+		status &= ~PORT_IRQ_BAD_PMP;
+
+	/* if LPM is enabled, PHYRDY doesn't mean anything */
+	if (ap->link.lpm_policy > ATA_LPM_MAX_POWER) {
+		status &= ~PORT_IRQ_PHYRDY;
+		ahci_scr_write(&ap->link, SCR_ERROR, SERR_PHYRDY_CHG);
+	}
+
+	if (unlikely(status & PORT_IRQ_ERROR)) {
+		ahci_error_intr(ap, status);
+		return;
+	}
+
+	if (status & PORT_IRQ_SDB_FIS) {
+		/* If SNotification is available, leave notification
+		 * handling to sata_async_notification().  If not,
+		 * emulate it by snooping SDB FIS RX area.
+		 *
+		 * Snooping FIS RX area is probably cheaper than
+		 * poking SNotification but some constrollers which
+		 * implement SNotification, ICH9 for example, don't
+		 * store AN SDB FIS into receive area.
+		 */
+		if (hpriv->cap & HOST_CAP_SNTF)
+			sata_async_notification(ap);
+		else {
+			/* If the 'N' bit in word 0 of the FIS is set,
+			 * we just received asynchronous notification.
+			 * Tell libata about it.
+			 *
+			 * Lack of SNotification should not appear in
+			 * ahci 1.2, so the workaround is unnecessary
+			 * when FBS is enabled.
+			 */
+			if (pp->fbs_enabled)
+				WARN_ON_ONCE(1);
+			else {
+				const __le32 *f = pp->rx_fis + RX_FIS_SDB;
+				u32 f0 = le32_to_cpu(f[0]);
+				if (f0 & (1 << 15))
+					sata_async_notification(ap);
+			}
+		}
+	}
+
+	/* pp->active_link is not reliable once FBS is enabled, both
+	 * PORT_SCR_ACT and PORT_CMD_ISSUE should be checked because
+	 * NCQ and non-NCQ commands may be in flight at the same time.
+	 */
+	if (pp->fbs_enabled) {
+		if (ap->qc_active) {
+			qc_active = readl(port_mmio + PORT_SCR_ACT);
+			qc_active |= readl(port_mmio + PORT_CMD_ISSUE);
+		}
+	} else {
+		/* pp->active_link is valid iff any command is in flight */
+		if (ap->qc_active && pp->active_link->sactive)
+			qc_active = readl(port_mmio + PORT_SCR_ACT);
+		else
+			qc_active = readl(port_mmio + PORT_CMD_ISSUE);
+	}
+
+	/* Flush the IOB before servicing interrupt to ensure all data
+	   written by the controller appears in DDR */
+	xgene_ahci_iob_flush((struct xgene_ahci_context *) hpriv);
+
+	rc = ata_qc_complete_multiple(ap, qc_active);
+
+	/* while resetting, invalid completions are expected */
+	if (unlikely(rc < 0 && !resetting)) {
+		ehi->err_mask |= AC_ERR_HSM;
+		ehi->action |= ATA_EH_RESET;
+		ata_port_freeze(ap);
+	}
+}
+
+static irqreturn_t xgene_ahci_interrupt(int irq, void *dev_instance)
+{
+	struct ata_host *host = dev_instance;
+	struct ahci_host_priv *hpriv;
+	unsigned int i, handled = 0;
+	void __iomem *mmio;
+	u32 irq_stat, irq_masked;
+
+	VPRINTK("ENTER\n");
+
+	hpriv = host->private_data;
+	mmio = hpriv->mmio;
+
+	/* sigh.  0xffffffff is a valid return from h/w */
+	irq_stat = readl(mmio + HOST_IRQ_STAT);
+	if (!irq_stat)
+		return IRQ_NONE;
+
+	irq_masked = irq_stat & hpriv->port_map;
+
+	spin_lock(&host->lock);
+
+	for (i = 0; i < host->n_ports; i++) {
+		struct ata_port *ap;
+
+		if (!(irq_masked & (1 << i)))
+			continue;
+
+		ap = host->ports[i];
+		if (ap) {
+			xgene_ahci_port_intr(ap);
+			VPRINTK("port %u\n", i);
+		} else {
+			VPRINTK("port %u (no irq)\n", i);
+			if (ata_ratelimit())
+				dev_warn(host->dev,
+					 "interrupt on disabled port %u\n", i);
+		}
+
+		handled = 1;
+	}
+
+	/* HOST_IRQ_STAT behaves as level triggered latch meaning that
+	 * it should be cleared after all the port events are cleared;
+	 * otherwise, it will raise a spurious interrupt after each
+	 * valid one.  Please read section 10.6.2 of ahci 1.1 for more
+	 * information.
+	 *
+	 * Also, use the unmasked value to clear interrupt as spurious
+	 * pending event on a dummy port might cause screaming IRQ.
+	 */
+	writel(irq_stat, mmio + HOST_IRQ_STAT);
+
+	spin_unlock(&host->lock);
+
+	VPRINTK("EXIT\n");
+
+	return IRQ_RETVAL(handled);
+}
+
+static int xgene_ahci_hw_init(struct xgene_ahci_context *hpriv)
+{
+	int i;
+	int rc;
+	u32 val;
+
+	/* Remove IP RAM out of shutdown */
+	xgene_ahci_init_memram(hpriv);
+
+	for (i = 0; i < MAX_AHCI_CHN_PERCTR; i++)
+		xgene_ahci_set_phy_cfg(hpriv, i);
+
+	/* Map in the IOB register */
+	rc = xgene_ahci_iob_flush(hpriv);
+
+	/* Now enable top level interrupt. Otherwise, port interrupt will
+	   not work. */
+	/* AXI disable Mask */
+	xgene_wr_flush(hpriv->mmio_base + HOST_IRQ_STAT, 0xffffffff);
+	xgene_wr(hpriv->csr_base + INTSTATUSMASK_ADDR, 0);
+	xgene_rd(hpriv->csr_base + INTSTATUSMASK_ADDR, &val);
+	dev_dbg(hpriv->dev,
+		"SATA%d top level interrupt mask 0x%X value 0x%08X\n",
+		hpriv->cid, INTSTATUSMASK_ADDR, val);
+	xgene_wr_flush(hpriv->csr_base + ERRINTSTATUSMASK_ADDR, 0x0);
+	xgene_wr_flush(hpriv->csr_base + SATA_SHIM_OFFSET +
+			       INT_SLV_TMOMASK_ADDR, 0x0);
+	/* Enable AXI Interrupt */
+	xgene_wr(hpriv->csr_base + SLVRDERRATTRIBUTES_ADDR, 0xffffffff);
+	xgene_wr(hpriv->csr_base + SLVWRERRATTRIBUTES_ADDR, 0xffffffff);
+	xgene_wr(hpriv->csr_base + MSTRDERRATTRIBUTES_ADDR, 0xffffffff);
+	xgene_wr(hpriv->csr_base + MSTWRERRATTRIBUTES_ADDR, 0xffffffff);
+
+	/* Enable coherency unless explicit disabled */
+	xgene_rd(hpriv->csr_base + BUSCTLREG_ADDR, &val);
+	val = MSTAWAUX_COHERENT_BYPASS_SET(val, 0);
+	val = MSTARAUX_COHERENT_BYPASS_SET(val, 0);
+	xgene_wr(hpriv->csr_base + BUSCTLREG_ADDR, val);
+
+	xgene_rd(hpriv->csr_base + IOFMSTRWAUX_ADDR, &val);
+	val |= (1 << 3);	/* Enable read coherency */
+	val |= (1 << 9);	/* Enable write coherency */
+	xgene_wr_flush(hpriv->csr_base + IOFMSTRWAUX_ADDR, val);
+	xgene_rd(hpriv->csr_base + IOFMSTRWAUX_ADDR, &val);
+	dev_dbg(hpriv->dev,
+		"SATA%d coherency 0x%X value 0x%08X\n",
+		hpriv->cid, IOFMSTRWAUX_ADDR, val);
+
+	return rc;
+}
+
+static int xgene_ahci_get_u32_param(struct platform_device *pdev,
+				    const char *of_name, char *acpi_name,
+				    u32 *param)
+{
+#ifdef CONFIG_ACPI
+	if (efi_enabled(EFI_BOOT)) {
+		unsigned long long value;
+		acpi_status status;
+		if (acpi_name == NULL)
+			return -ENODEV;
+		status = acpi_evaluate_integer(ACPI_HANDLE(&pdev->dev),
+					       acpi_name, NULL, &value);
+		if (ACPI_FAILURE(status))
+			return -ENODEV;
+		*param = value;
+		return 0;
+	}
+#endif
+	if (of_name == NULL)
+		return -ENODEV;
+	return of_property_read_u32(pdev->dev.of_node, of_name, param);
+}
+
+static int xgene_ahci_get_str_param(struct platform_device *pdev,
+				    const char *of_name, char *acpi_name,
+				    char *buf, int len)
+{
+	int rc;
+	const char *param;
+#ifdef CONFIG_ACPI
+	if (efi_enabled(EFI_BOOT)) {
+		acpi_status status;
+		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+		union acpi_object *acpi_obj;
+
+		if (acpi_name == NULL)
+			return -ENODEV;
+		status = acpi_evaluate_object(ACPI_HANDLE(&pdev->dev),
+					      acpi_name, NULL, &buffer);
+		if (ACPI_FAILURE(status))
+			return -ENODEV;
+		acpi_obj = buffer.pointer;
+		if (acpi_obj->type != ACPI_TYPE_STRING) {
+			buf[0] = '\0';
+			kfree(buffer.pointer);
+			return -ENODEV;
+		}
+		if (acpi_obj->string.length < len) {
+			strncpy(buf, acpi_obj->string.pointer,
+				acpi_obj->string.length);
+			buf[acpi_obj->string.length] = '\0';
+		} else {
+			strncpy(buf, acpi_obj->string.pointer, len);
+			buf[len - 1] = '\0';
+		}
+		kfree(buffer.pointer);
+		return 0;
+	}
+#endif
+	if (of_name == NULL) {
+		buf[0] = '\0';
+		return 0;
+	}
+	rc = of_property_read_string(pdev->dev.of_node, of_name, &param);
+	if (rc == 0) {
+		strncpy(buf, param, len);
+		buf[len - 1] = '\0';
+	} else {
+		buf[0] = '\0';
+	}
+	return rc;
+}
+
+static int xgene_ahci_probe(struct platform_device *pdev)
+{
+	struct xgene_ahci_context *hpriv;
+	struct ata_port_info pi = xgene_ahci_port_info[0];
+	const struct ata_port_info *ppi[] = { &pi, NULL };
+	struct ata_host *host;
+	struct resource *res;
+	char res_name[30];
+	int n_ports;
+	int rc = 0;
+	int i;
+
+	/* When both ACPi and DTS are enabled, custom ACPI built-in ACPI
+	   table, and booting via DTS, we need to skip the probe of the
+	   built-in ACPI table probe. */
+	if (!efi_enabled(EFI_BOOT) && pdev->dev.of_node == NULL)
+		return -ENODEV;
+
+	/* Check if the entry is disabled for OF only */
+	if (!efi_enabled(EFI_BOOT) &&
+	    !of_device_is_available(pdev->dev.of_node))
+		return -ENODEV;
+#if defined(CONFIG_ACPI)
+	if (efi_enabled(EFI_BOOT)) {
+		struct acpi_device *device;
+
+		if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &device))
+			return -ENODEV;
+
+		if (acpi_bus_get_status(device) || !device->status.present)
+			return -ENODEV;
+	}
+#endif
+
+	hpriv = devm_kzalloc(&pdev->dev, sizeof(*hpriv), GFP_KERNEL);
+	if (!hpriv) {
+		dev_err(&pdev->dev, "can't allocate host context\n");
+		return -ENOMEM;
+	}
+	hpriv->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "no AHCI resource address\n");
+		goto error;
+	}
+	hpriv->mmio_phys = res->start;
+	hpriv->mmio_base = devm_ioremap(&pdev->dev, res->start,
+					resource_size(res));
+	if (!hpriv->mmio_base) {
+		dev_err(&pdev->dev, "can't map MMIO resource\n");
+		rc = -ENOMEM;
+		goto error;
+	}
+	hpriv->hpriv.mmio = hpriv->mmio_base;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!res) {
+		dev_err(&pdev->dev, "no Serdes resource address\n");
+		goto error;
+	}
+	hpriv->csr_phys = res->start;
+	hpriv->csr_base = devm_ioremap(&pdev->dev, res->start,
+				       resource_size(res));
+	if (!hpriv->csr_base) {
+		dev_err(&pdev->dev, "can't map Serdes CSR resource\n");
+		rc = -ENOMEM;
+		goto error;
+	}
+
+	rc = xgene_ahci_get_u32_param(pdev, "id", "ID00", &hpriv->cid);
+	if (rc != 0) {
+		dev_err(&pdev->dev, "no controller ID resource\n");
+		goto error;
+	}
+
+	rc = xgene_ahci_get_str_param(pdev, NULL, "CLNM", res_name,
+				      sizeof(res_name));
+	if (rc) {
+		dev_err(&pdev->dev, "no clock name resource\n");
+		goto error;
+	}
+	hpriv->hpriv.clk = clk_get(&pdev->dev,
+				   res_name[0] == '\0' ? NULL : res_name);
+	if (!IS_ERR(hpriv->hpriv.clk)) {
+		rc = clk_prepare_enable(hpriv->hpriv.clk);
+		if (rc) {
+			dev_err(&pdev->dev, "clock prepare enable failed\n");
+			goto error;
+		}
+	} else {
+		dev_warn(&pdev->dev, "no clock\n");
+	}
+
+	dev_dbg(&pdev->dev,
+		"SATA%d PHY PAddr 0x%016LX VAddr 0x%p Mmio PAddr 0x%016LX VAddr 0x%p\n",
+		hpriv->cid, hpriv->csr_phys, hpriv->csr_base, hpriv->mmio_phys,
+		hpriv->mmio_base);
+
+	hpriv->irq = platform_get_irq(pdev, 0);
+	if (hpriv->irq <= 0) {
+		dev_err(&pdev->dev, "no IRQ resource\n");
+		rc = -ENODEV;
+		goto error;
+	}
+
+	/* Configure the PHY */
+	sprintf(res_name, "sataphy%d", hpriv->cid);
+	hpriv->phy = devm_phy_get(&pdev->dev, res_name);
+	if (!hpriv->phy) {
+		dev_err(&pdev->dev, "SATA%d no PHY available\n", hpriv->cid);
+		goto error;
+	}
+
+	rc = phy_init(hpriv->phy);
+	if (rc) {
+		dev_err(&pdev->dev, "SATA%d PHY initialize failed %d\n",
+			hpriv->cid, rc);
+		goto error;
+	}
+
+	/* Configure the host controller */
+	xgene_ahci_hw_init(hpriv);
+
+	/* Setup AHCI host priv structure */
+	ahci_save_initial_config(&pdev->dev, &hpriv->hpriv, 0, 0);
+
+	/* prepare host */
+	if (hpriv->hpriv.cap & HOST_CAP_NCQ)
+		pi.flags |= ATA_FLAG_NCQ;
+	if (hpriv->hpriv.cap & HOST_CAP_PMP) {
+		pi.flags |= ATA_FLAG_PMP;
+		if (hpriv->hpriv.cap & HOST_CAP_FBS)
+			hpriv->hpriv.flags |= AHCI_HFLAG_YES_FBS;
+	}
+	ahci_set_em_messages(&hpriv->hpriv, &pi);
+
+	/* CAP.NP sometimes indicate the index of the last enabled
+	 * port, at other times, that of the last possible port, so
+	 * determining the maximum port number requires looking at
+	 * both CAP.NP and port_map.
+	 */
+	n_ports = max(ahci_nr_ports(hpriv->hpriv.cap),
+		      fls(hpriv->hpriv.port_map));
+
+	host = ata_host_alloc_pinfo(&pdev->dev, ppi, n_ports);
+	if (!host) {
+		dev_err(&pdev->dev, "can not allocate host pinfo\n");
+		rc = -ENOMEM;
+		goto error;
+	}
+
+	host->private_data = hpriv;
+
+	if (!(hpriv->hpriv.cap & HOST_CAP_SSS) || ahci_ignore_sss)
+		host->flags |= ATA_HOST_PARALLEL_SCAN;
+	else
+		dev_warn(&pdev->dev,
+			 "ahci: SSS flag set, parallel bus scan disabled\n");
+
+	if (pi.flags & ATA_FLAG_EM)
+		ahci_reset_em(host);
+
+	for (i = 0; i < host->n_ports; i++) {
+		struct ata_port *ap = host->ports[i];
+
+		ata_port_desc(ap, "mmio 0x%llX", hpriv->mmio_phys);
+		ata_port_desc(ap, "port 0x%x", 0x100 + ap->port_no * 0x80);
+
+		/* set enclosure management message type */
+		if (ap->flags & ATA_FLAG_EM)
+			ap->em_message_type = hpriv->hpriv.em_msg_type;
+
+		/* disabled/not-implemented port */
+		if (!(hpriv->hpriv.port_map & (1 << i)))
+			ap->ops = &ata_dummy_port_ops;
+	}
+
+	rc = ahci_reset_controller(host);
+	if (rc)
+		goto error;
+
+	ahci_init_controller(host);
+	ahci_print_info(host, "XGene-AHCI\n");
+
+	/* Setup DMA mask */
+	dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
+	dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
+
+	rc = ata_host_activate(host, hpriv->irq, xgene_ahci_interrupt,
+			       IRQF_SHARED, &xgene_ahci_sht);
+	if (rc)
+		goto error;
+
+	dev_dbg(&pdev->dev, "SATA%d PHY initialized\n", hpriv->cid);
+	return 0;
+
+error:
+	devm_kfree(&pdev->dev, hpriv);
+	return rc;
+}
+
+static int xgene_ahci_remove(struct platform_device *pdev)
+{
+	struct ata_host *host = dev_get_drvdata(&pdev->dev);
+	struct xgene_ahci_context *hpriv = host->private_data;
+
+	dev_dbg(&pdev->dev, "SATA%d remove\n", hpriv->cid);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int xgene_ahci_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct ata_host *host = dev_get_drvdata(&pdev->dev);
+	struct xgene_ahci_context *hpriv = host->private_data;
+	void __iomem *mmio = hpriv->mmio_base;
+	u32 ctl;
+	int rc;
+
+	dev_dbg(&pdev->dev, "SATA%d suspend\n", hpriv->cid);
+
+	/*
+	 * AHCI spec rev1.1 section 8.3.3:
+	 * Software must disable interrupts prior to requesting a
+	 * transition of the HBA to D3 state.
+	 */
+	ctl = readl(mmio + HOST_CTL);
+	ctl &= ~HOST_IRQ_EN;
+	writel(ctl, mmio + HOST_CTL);
+	readl(mmio + HOST_CTL);	/* flush */
+
+	rc = ata_host_suspend(host, state);
+	if (rc)
+		return rc;
+
+	if (!IS_ERR(hpriv->hpriv.clk))
+		clk_disable_unprepare(hpriv->hpriv.clk);
+	return 0;
+}
+
+static int xgene_ahci_resume(struct platform_device *pdev)
+{
+	struct ata_host *host = dev_get_drvdata(&pdev->dev);
+	struct xgene_ahci_context *hpriv = host->private_data;
+	int rc;
+
+	dev_dbg(&pdev->dev, "SATA%d resume\n", hpriv->cid);
+
+	if (!IS_ERR(hpriv->hpriv.clk)) {
+		rc = clk_prepare_enable(hpriv->hpriv.clk);
+		if (rc) {
+			dev_err(&pdev->dev, "clock prepare enable failed\n");
+			return rc;
+		}
+	}
+
+	if (pdev->dev.power.power_state.event == PM_EVENT_SUSPEND) {
+		rc = ahci_reset_controller(host);
+		if (rc)
+			goto disable_unprepare_clk;
+
+		ahci_init_controller(host);
+	}
+
+	ata_host_resume(host);
+	return 0;
+
+disable_unprepare_clk:
+	if (!IS_ERR(hpriv->hpriv.clk))
+		clk_disable_unprepare(hpriv->hpriv.clk);
+
+	return rc;
+}
+#endif
+
+static const struct acpi_device_id xgene_ahci_acpi_match[] = {
+	{"APMC0D00", 0},
+	{},
+};
+
+MODULE_DEVICE_TABLE(acpi, xgene_ahci_acpi_match);
+
+static const struct of_device_id xgene_ahci_of_match[] = {
+	{.compatible = "apm,xgene-ahci",},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, xgene_ahci_of_match);
+
+static struct platform_driver xgene_ahci_driver = {
+	.driver = {
+		   .name = "xgene-ahci",
+		   .owner = THIS_MODULE,
+		   .of_match_table = xgene_ahci_of_match,
+		   .acpi_match_table = ACPI_PTR(xgene_ahci_acpi_match),
+		   },
+	.probe = xgene_ahci_probe,
+	.remove = xgene_ahci_remove,
+#ifdef CONFIG_PM
+	.suspend = xgene_ahci_suspend,
+	.resume = xgene_ahci_resume,
+#endif
+};
+
+module_platform_driver(xgene_ahci_driver);
+
+MODULE_DESCRIPTION("APM X-Gene AHCI SATA driver");
+MODULE_AUTHOR("Loc Ho <lho@apm.com>");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("0.3");
diff --git a/drivers/ata/sata_xgene.h b/drivers/ata/sata_xgene.h
new file mode 100644
index 0000000..51e73f6
--- /dev/null
+++ b/drivers/ata/sata_xgene.h
@@ -0,0 +1,96 @@ 
+/*
+ * AppliedMicro X-Gene SATA PHY driver
+ *
+ * Copyright (c) 2013, Applied Micro Circuits Corporation
+ * Author: Loc Ho <lho@apm.com>
+ *         Tuan Phan <tphan@apm.com>
+ *         Suman Tripathi <stripathi@apm.com>
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __SATA_XGENE_H__
+#define __SATA_XGENE_H__
+
+#include "ahci.h"	/* for ahci_host_priv */
+
+/* Default tuning parameters */
+#define XGENE_SERDES_VAL_NOT_SET	~0x0
+#define CTLE_EQ				0x9
+#define PQ_REG				0x8
+#define CTLE_EQ_A2			0x2
+#define PQ_REG_A2			0xa
+#define SPD_SEL				0x5
+
+/*
+ * Configure Reference clock (clock type):
+ *  External differential 0
+ *  Internal differential 1
+ *  Internal single ended 2
+ */
+#define SATA_CLK_EXT_DIFF		0
+#define SATA_CLK_INT_DIFF		1
+#define SATA_CLK_INT_SING		2
+
+struct xgene_ahci_context {
+	struct ahci_host_priv  hpriv;
+	struct device *dev;
+	u32 cid;		/* Controller ID */
+	int irq;		/* IRQ */
+	void *csr_base;		/* CSR base address of IP */
+	u64 csr_phys;		/* Physical address of CSR base address */
+	void *mmio_base;	/* AHCI I/O base address */
+	u64 mmio_phys;		/* Physical address of MMIO base address */
+	void *ahbc_io_base;	/* Used for IOB flushing */
+
+	struct phy *phy;
+
+#if 0
+	void *pcie_base;	/* Shared Serdes CSR in PCIe 4/5 domain */
+	/* Override Serdes parameters */
+	u32 ctrl_eq_A1; /* Serdes Reg 1 RX/TX ctrl_eq value for A1 */
+	u32 ctrl_eq;	/* Serdes Reg 1 RX/TX ctrl_eq value */
+	u32 pq_A1;	/* Serdes Reg 125 pq value for A1 */
+	u32 pq;		/* Serdes Reg 125 pq value */
+	u32 pq_sign;	/* Serdes Reg 125 pq sign */
+	u32 loopback_buf_en_A1; /* Serdes Reg 4 Tx loopback buf enable for A1 */
+	u32 loopback_buf_en;	/* Serdes Reg 4 Tx loopback buf enable */
+	u32 loopback_ena_ctle_A1; /* Serdes Reg 7 loopback enable ctrl for A1 */
+	u32 loopback_ena_ctle;	/* Serdes Reg 7 loopback enable ctrl */
+	u32 spd_sel_cdr_A1;	/* Serdes Reg 61 spd sel cdr value for A1*/
+	u32 spd_sel_cdr;	/* Serdes Reg 61 spd sel cdr value */
+	u32 use_gen_avg;	/* Use generate average value */
+
+	u32 coherent;		/* Coherent IO */
+#endif
+};
+
+void xgene_ahci_in32(void *addr, u32 *val);
+void xgene_ahci_out32(void *addr, u32 val);
+void xgene_ahci_out32_flush(void *addr, u32 val);
+void xgene_ahci_delayus(unsigned long us);
+void xgene_ahci_delayms(unsigned long ms);
+int xgene_ahci_is_A1(void);
+
+void xgene_ahci_serdes_force_gen(struct xgene_ahci_context *ctx, int channel,
+	int gen);
+void xgene_ahci_serdes_set_pq(struct xgene_ahci_context *ctx, int channel,
+	int data);
+int xgene_ahci_port_start(struct ata_port *ap);
+int xgene_ahci_port_resume(struct ata_port *ap);
+#define xgene_ahci_fill_cmd_slot	ahci_fill_cmd_slot
+#define xgene_ahci_exec_polled_cmd	ahci_exec_polled_cmd
+#define xgene_ahci_to_axi(x)		(x)
+#define xgene_ahci_dflush(x, ...)
+
+#endif /* __SATA_XGENE_H__ */