[PATCH v4 0/2] ata: ahci_xgene: Add support for 2nd HW version of APM X-Gene SoC AHCI SATA Host controller driver.

[PATCH v4 0/2] ata: ahci_xgene: Add support for 2nd HW version of APM X-Gene SoC AHCI SATA Host controller driver.

[Suman Tripathi]

V2 change:
 * Drop the MIDR based implementation.

V3 change:
 * Implement the support for HOST_IRQ_STAT as edge trigger latch.

V4 change:
 * Implement seperate irq handler for level and edge trigger latch.

Signed-off-by: Suman Tripathi <stripathi@apm.com>
---

Suman Tripathi (2):
  libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch.
  ata: ahci_xgene: Add AHCI Support for 2nd HW version of APM X-Gene SoC
    AHCI SATA     Host controller.

 drivers/ata/ahci.h       |  2 ++
 drivers/ata/ahci_xgene.c | 90 ++++++++++++++++++++++++++++++++++++----------
 drivers/ata/libahci.c    | 93 ++++++++++++++++++++++++++++++++++++------------
 3 files changed, 145 insertions(+), 40 deletions(-)

--
1.8.2.1

[PATCH v4 1/2] libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch.

[Suman Tripathi]

This patch adds the support to handle HOST_IRQ_STAT as edge trigger
latch.

Signed-off-by: Suman Tripathi <stripathi@apm.com>
---
 drivers/ata/ahci.h    |  2 ++
 drivers/ata/libahci.c | 93 +++++++++++++++++++++++++++++++++++++++------------
 2 files changed, 73 insertions(+), 22 deletions(-)

diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 71262e0..2df2237 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -238,6 +238,8 @@ enum {
 	AHCI_HFLAG_MULTI_MSI		= (1 << 16), /* multiple PCI MSIs */
 	AHCI_HFLAG_NO_DEVSLP		= (1 << 17), /* no device sleep */
 	AHCI_HFLAG_NO_FBS		= (1 << 18), /* no FBS */
+	AHCI_HFLAG_EDGE_TRIG_IRQ	= (1 << 19), /* HOST_IRQ_STAT behaves as
+							Edge Triggered */

 	/* ap->flags bits */

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 61a9c07..6f1a603 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -1826,27 +1826,9 @@ static irqreturn_t ahci_multi_irqs_intr(int irq, void *dev_instance)
 	return IRQ_WAKE_THREAD;
 }

-static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
+static u32 ahci_handle_port_intr(struct ata_host *host, u32 irq_masked)
 {
-	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;
@@ -1864,10 +1846,36 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
 				dev_warn(host->dev,
 					 "interrupt on disabled port %u\n", i);
 		}
-
 		handled = 1;
 	}

+	return handled;
+}
+
+static irqreturn_t ahci_level_trig_intr(int irq, void *dev_instance)
+{
+	struct ata_host *host = dev_instance;
+	struct ahci_host_priv *hpriv;
+	unsigned int rc = 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);
+
+	rc = ahci_handle_port_intr(host, irq_masked);
+
 	/* 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
@@ -1877,13 +1885,51 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
 	 * 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(rc);
+}
+
+static irqreturn_t ahci_edge_trig_intr(int irq, void *dev_instance)
+{
+	struct ata_host *host = dev_instance;
+	struct ahci_host_priv *hpriv;
+	unsigned int rc = 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);
+
+	/*
+	 * HOST_IRQ_STAT behaves as edge triggered latch meaning that
+	 * it should be cleared before all the port events are cleared;
+	 */
 	writel(irq_stat, mmio + HOST_IRQ_STAT);

+	rc = ahci_handle_port_intr(host, irq_masked);
+
 	spin_unlock(&host->lock);

 	VPRINTK("EXIT\n");

-	return IRQ_RETVAL(handled);
+	return IRQ_RETVAL(rc);
 }

 unsigned int ahci_qc_issue(struct ata_queued_cmd *qc)
@@ -2486,8 +2532,11 @@ int ahci_host_activate(struct ata_host *host, int irq,

 	if (hpriv->flags & AHCI_HFLAG_MULTI_MSI)
 		rc = ahci_host_activate_multi_irqs(host, irq, sht);
+	else if (hpriv->flags & AHCI_HFLAG_EDGE_TRIG_IRQ)
+		rc = ata_host_activate(host, irq, ahci_edge_trig_intr,
+				       IRQF_SHARED, sht);
 	else
-		rc = ata_host_activate(host, irq, ahci_single_irq_intr,
+		rc = ata_host_activate(host, irq, ahci_level_trig_intr,
 				       IRQF_SHARED, sht);
 	return rc;
 }
--
1.8.2.1

[PATCH v4 2/2] ata: ahci_xgene: Add AHCI Support for 2nd HW version of APM X-Gene SoC AHCI SATA Host controller.

[Suman Tripathi]

This patch enables full AHCI feature support for APM X-Gene SoC SATA
host controller. The following errata's are removed:

1. 2a0bdff6b95 ("ahci-xgene: fix the dma state machine lockup for the
                 IDENTIFY DEVICE PIO mode command")
2. 09c32aaa368 ("ahci_xgene: Fix the dma state machine lockup for the
                 ATA_CMD_SMART PIO mode command")
3. 1540035da71 ("ahci_xgene: Implement the xgene_ahci_poll_reg_val to
                 support PMP")
4. a3a84bc7c88 ("ahci_xgene: Implement the workaround to support PMP
                 enumeration and discovery")
5. 1102407bb71 ("ahci_xgene: Fix the DMA state machine lockup for the
                 ATA_CMD_PACKET PIO mode command")
6. 72f79f9e35b ("ahci_xgene: Removing NCQ support from the APM X-Gene
		SoC AHCI SATA Host Controller driver")

In addition, enable PMP support for APM X-Gene SoC and enable FBS
support for second generation APM X-Gene SoC.

Signed-off-by: Suman Tripathi <stripathi@apm.com>
---
 drivers/ata/ahci_xgene.c | 90 ++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 72 insertions(+), 18 deletions(-)

diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c
index 2b78510..2ced663 100644
--- a/drivers/ata/ahci_xgene.c
+++ b/drivers/ata/ahci_xgene.c
@@ -27,6 +27,7 @@
 #include <linux/platform_device.h>
 #include <linux/ahci_platform.h>
 #include <linux/of_address.h>
+#include <linux/of_device.h>
 #include <linux/of_irq.h>
 #include <linux/phy/phy.h>
 #include "ahci.h"
@@ -84,6 +85,11 @@
 /* Max retry for link down */
 #define MAX_LINK_DOWN_RETRY 3

+enum xgene_ahci_version {
+	XGENE_AHCI_V1 = 1,
+	XGENE_AHCI_V2,
+};
+
 struct xgene_ahci_context {
 	struct ahci_host_priv *hpriv;
 	struct device *dev;
@@ -547,9 +553,6 @@ static struct ata_port_operations xgene_ahci_ops = {
 	.host_stop = xgene_ahci_host_stop,
 	.hardreset = xgene_ahci_hardreset,
 	.read_id = xgene_ahci_read_id,
-	.qc_issue = xgene_ahci_qc_issue,
-	.softreset = xgene_ahci_softreset,
-	.pmp_softreset = xgene_ahci_pmp_softreset
 };

 static const struct ata_port_info xgene_ahci_port_info = {
@@ -629,12 +632,30 @@ static struct scsi_host_template ahci_platform_sht = {
 	AHCI_SHT(DRV_NAME),
 };

+#ifdef CONFIG_ACPI
+static const struct acpi_device_id xgene_ahci_acpi_match[] = {
+	{ "APMC0D0D", XGENE_AHCI_V1},
+	{ "APMC0D32", XGENE_AHCI_V2},
+	{},
+};
+MODULE_DEVICE_TABLE(acpi, xgene_ahci_acpi_match);
+#endif
+
+static const struct of_device_id xgene_ahci_of_match[] = {
+	{.compatible = "apm,xgene-ahci", .data = (void *) XGENE_AHCI_V1},
+	{.compatible = "apm,xgene-ahci-v2", .data = (void *) XGENE_AHCI_V2},
+	{},
+};
+MODULE_DEVICE_TABLE(of, xgene_ahci_of_match);
+
 static int xgene_ahci_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct ahci_host_priv *hpriv;
 	struct xgene_ahci_context *ctx;
 	struct resource *res;
+	const struct of_device_id *of_devid;
+	enum xgene_ahci_version version = XGENE_AHCI_V1;
 	int rc;

 	hpriv = ahci_platform_get_resources(pdev);
@@ -677,6 +698,37 @@ static int xgene_ahci_probe(struct platform_device *pdev)
 		ctx->csr_mux = csr;
 	}

+	of_devid = of_match_device(xgene_ahci_of_match, dev);
+	if (of_devid) {
+		if (of_devid->data)
+			version = (enum xgene_ahci_version) of_devid->data;
+	}
+#ifdef CONFIG_ACPI
+	else {
+		const struct acpi_device_id *acpi_id;
+		struct acpi_device_info *info;
+		acpi_status status;
+
+		acpi_id = acpi_match_device(xgene_ahci_acpi_match, &pdev->dev);
+		if (!acpi_id) {
+			dev_warn(&pdev->dev, "No node entry in ACPI table. Assume version1\n");
+			version = XGENE_AHCI_V1;
+		}
+
+		if (acpi_id->driver_data) {
+			version = (enum xgene_ahci_version) acpi_id->driver_data;
+			status = acpi_get_object_info(ACPI_HANDLE(&pdev->dev), &info);
+			if (ACPI_FAILURE(status)) {
+				dev_warn(&pdev->dev, "%s: Error reading device info. Assume version1\n",
+					__func__);
+				version = XGENE_AHCI_V1;
+			}
+			if (info->valid & ACPI_VALID_CID)
+				version = XGENE_AHCI_V2;
+		}
+	}
+#endif
+
 	dev_dbg(dev, "VAddr 0x%p Mmio VAddr 0x%p\n", ctx->csr_core,
 		hpriv->mmio);

@@ -704,7 +756,23 @@ static int xgene_ahci_probe(struct platform_device *pdev)
 	/* Configure the host controller */
 	xgene_ahci_hw_init(hpriv);
 skip_clk_phy:
-	hpriv->flags = AHCI_HFLAG_NO_PMP | AHCI_HFLAG_NO_NCQ;
+
+	switch (version) {
+	case XGENE_AHCI_V1:
+		hpriv->flags = AHCI_HFLAG_NO_NCQ;
+		/*
+		 * Override the callbacks for storm ERRATA
+		 */
+		xgene_ahci_ops.qc_issue = xgene_ahci_qc_issue;
+		xgene_ahci_ops.softreset = xgene_ahci_softreset;
+		xgene_ahci_ops.pmp_softreset = xgene_ahci_pmp_softreset;
+		break;
+	case XGENE_AHCI_V2:
+		hpriv->flags |= AHCI_HFLAG_YES_FBS | AHCI_HFLAG_EDGE_TRIG_IRQ;
+		break;
+	default:
+		break;
+	}

 	rc = ahci_platform_init_host(pdev, hpriv, &xgene_ahci_port_info,
 				     &ahci_platform_sht);
@@ -719,20 +787,6 @@ disable_resources:
 	return rc;
 }

-#ifdef CONFIG_ACPI
-static const struct acpi_device_id xgene_ahci_acpi_match[] = {
-	{ "APMC0D0D", },
-	{ }
-};
-MODULE_DEVICE_TABLE(acpi, xgene_ahci_acpi_match);
-#endif
-
-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 = {
 	.probe = xgene_ahci_probe,
 	.remove = ata_platform_remove_one,
--
1.8.2.1

Re: [PATCH v4 1/2] libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch.

[Tejun Heo]

Hello, Suman.

Looks pretty.  Some nitpicks.

On Tue, May 05, 2015 at 08:43:41PM +0530, Suman Tripathi wrote:
> diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
> index 71262e0..2df2237 100644
> --- a/drivers/ata/ahci.h
> +++ b/drivers/ata/ahci.h
> @@ -238,6 +238,8 @@ enum {
>  	AHCI_HFLAG_MULTI_MSI		= (1 << 16), /* multiple PCI MSIs */
>  	AHCI_HFLAG_NO_DEVSLP		= (1 << 17), /* no device sleep */
>  	AHCI_HFLAG_NO_FBS		= (1 << 18), /* no FBS */
> +	AHCI_HFLAG_EDGE_TRIG_IRQ	= (1 << 19), /* HOST_IRQ_STAT behaves as
> +							Edge Triggered */

Let's just name it ahci_HFLAG_EDGE_IRQ.

> +static irqreturn_t ahci_level_trig_intr(int irq, void *dev_instance)

ahci_single_level_irq_intr()

> +{
...
> @@ -1877,13 +1885,51 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
>  	 * Also, use the unmasked value to clear interrupt as spurious
>  	 * pending event on a dummy port might cause screaming IRQ.
>  	 */
> +

Extra newline which wasn't there before.

> +	writel(irq_stat, mmio + HOST_IRQ_STAT);
> +
> +	spin_unlock(&host->lock);
> +
> +	VPRINTK("EXIT\n");
> +
> +	return IRQ_RETVAL(rc);
> +}
> +
> +static irqreturn_t ahci_edge_trig_intr(int irq, void *dev_instance)

ahci_single_edge_irq_intr()

And let's please separate refactoring of intr routine and addition of
edge irq handling into two patches.

Thanks.

-- 
tejun

[PATCH v4 1/2] libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch.

[Tejun Heo]

Hello, Suman.

Looks pretty.  Some nitpicks.

On Tue, May 05, 2015 at 08:43:41PM +0530, Suman Tripathi wrote:
> diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
> index 71262e0..2df2237 100644
> --- a/drivers/ata/ahci.h
> +++ b/drivers/ata/ahci.h
> @@ -238,6 +238,8 @@ enum {
>  	AHCI_HFLAG_MULTI_MSI		= (1 << 16), /* multiple PCI MSIs */
>  	AHCI_HFLAG_NO_DEVSLP		= (1 << 17), /* no device sleep */
>  	AHCI_HFLAG_NO_FBS		= (1 << 18), /* no FBS */
> +	AHCI_HFLAG_EDGE_TRIG_IRQ	= (1 << 19), /* HOST_IRQ_STAT behaves as
> +							Edge Triggered */

Let's just name it ahci_HFLAG_EDGE_IRQ.

> +static irqreturn_t ahci_level_trig_intr(int irq, void *dev_instance)

ahci_single_level_irq_intr()

> +{
...
> @@ -1877,13 +1885,51 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
>  	 * Also, use the unmasked value to clear interrupt as spurious
>  	 * pending event on a dummy port might cause screaming IRQ.
>  	 */
> +

Extra newline which wasn't there before.

> +	writel(irq_stat, mmio + HOST_IRQ_STAT);
> +
> +	spin_unlock(&host->lock);
> +
> +	VPRINTK("EXIT\n");
> +
> +	return IRQ_RETVAL(rc);
> +}
> +
> +static irqreturn_t ahci_edge_trig_intr(int irq, void *dev_instance)

ahci_single_edge_irq_intr()

And let's please separate refactoring of intr routine and addition of
edge irq handling into two patches.

Thanks.

-- 
tejun

Re: [PATCH v4 1/2] libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch.

[Suman Tripathi]

Hi Tejun,

On Tue, May 5, 2015 at 10:34 PM, Tejun Heo <tj@kernel.org> wrote:
> Hello, Suman.
>
> Looks pretty.  Some nitpicks.
>
> On Tue, May 05, 2015 at 08:43:41PM +0530, Suman Tripathi wrote:
>> diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
>> index 71262e0..2df2237 100644
>> --- a/drivers/ata/ahci.h
>> +++ b/drivers/ata/ahci.h
>> @@ -238,6 +238,8 @@ enum {
>>       AHCI_HFLAG_MULTI_MSI            = (1 << 16), /* multiple PCI MSIs */
>>       AHCI_HFLAG_NO_DEVSLP            = (1 << 17), /* no device sleep */
>>       AHCI_HFLAG_NO_FBS               = (1 << 18), /* no FBS */
>> +     AHCI_HFLAG_EDGE_TRIG_IRQ        = (1 << 19), /* HOST_IRQ_STAT behaves as
>> +                                                     Edge Triggered */
>
> Let's just name it ahci_HFLAG_EDGE_IRQ.

Sure

>
>> +static irqreturn_t ahci_level_trig_intr(int irq, void *dev_instance)
>
> ahci_single_level_irq_intr()
>
>> +{
> ...
>> @@ -1877,13 +1885,51 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
>>        * Also, use the unmasked value to clear interrupt as spurious
>>        * pending event on a dummy port might cause screaming IRQ.
>>        */
>> +
>
> Extra newline which wasn't there before.

sorry . Happened mistakenly

>
>> +     writel(irq_stat, mmio + HOST_IRQ_STAT);
>> +
>> +     spin_unlock(&host->lock);
>> +
>> +     VPRINTK("EXIT\n");
>> +
>> +     return IRQ_RETVAL(rc);
>> +}
>> +
>> +static irqreturn_t ahci_edge_trig_intr(int irq, void *dev_instance)
>
> ahci_single_edge_irq_intr()

Sure.

>
> And let's please separate refactoring of intr routine and addition of
> edge irq handling into two patches.

Okay


>
> Thanks.
>
> --
> tejun



-- 
Thanks,
with regards,
Suman Tripathi

[PATCH v4 1/2] libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch.

[Suman Tripathi]

Hi Tejun,

On Tue, May 5, 2015 at 10:34 PM, Tejun Heo <tj@kernel.org> wrote:
> Hello, Suman.
>
> Looks pretty.  Some nitpicks.
>
> On Tue, May 05, 2015 at 08:43:41PM +0530, Suman Tripathi wrote:
>> diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
>> index 71262e0..2df2237 100644
>> --- a/drivers/ata/ahci.h
>> +++ b/drivers/ata/ahci.h
>> @@ -238,6 +238,8 @@ enum {
>>       AHCI_HFLAG_MULTI_MSI            = (1 << 16), /* multiple PCI MSIs */
>>       AHCI_HFLAG_NO_DEVSLP            = (1 << 17), /* no device sleep */
>>       AHCI_HFLAG_NO_FBS               = (1 << 18), /* no FBS */
>> +     AHCI_HFLAG_EDGE_TRIG_IRQ        = (1 << 19), /* HOST_IRQ_STAT behaves as
>> +                                                     Edge Triggered */
>
> Let's just name it ahci_HFLAG_EDGE_IRQ.

Sure

>
>> +static irqreturn_t ahci_level_trig_intr(int irq, void *dev_instance)
>
> ahci_single_level_irq_intr()
>
>> +{
> ...
>> @@ -1877,13 +1885,51 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance)
>>        * Also, use the unmasked value to clear interrupt as spurious
>>        * pending event on a dummy port might cause screaming IRQ.
>>        */
>> +
>
> Extra newline which wasn't there before.

sorry . Happened mistakenly

>
>> +     writel(irq_stat, mmio + HOST_IRQ_STAT);
>> +
>> +     spin_unlock(&host->lock);
>> +
>> +     VPRINTK("EXIT\n");
>> +
>> +     return IRQ_RETVAL(rc);
>> +}
>> +
>> +static irqreturn_t ahci_edge_trig_intr(int irq, void *dev_instance)
>
> ahci_single_edge_irq_intr()

Sure.

>
> And let's please separate refactoring of intr routine and addition of
> edge irq handling into two patches.

Okay


>
> Thanks.
>
> --
> tejun



-- 
Thanks,
with regards,
Suman Tripathi