2014-11-10 05:30:30

by Robert Richter

[permalink] [raw]
Subject: [PATCH] AHCI: Add generic MSI-X interrupt support to SATA PCI driver

From: Sunil Goutham <[email protected]>

This patch adds generic support for MSI-X interrupts to the SATA PCI
driver. Only single interrupt support is implemented. Thus, per-port
interrupts can not yet be enabled.

The driver now checks the device for the existence of MSI-X and tries
to enable the interrupt. Otherwise, if a device is not MSI-X capable,
the initialization is skipped and MSI or intx interrupts are
configured.

This patch also enables AHCI for Cavium Thunder SoCs that uses MSI-X.

Signed-off-by: Sunil Goutham <[email protected]>
Signed-off-by: Robert Richter <[email protected]>
---
arch/arm64/Kconfig | 1 +
drivers/ata/ahci.c | 40 +++++++++++++++++++++++++++++++++++++++-
2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index ac9afde76dea..55970474d3ae 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -145,6 +145,7 @@ config ARCH_THUNDER
bool "Cavium Inc. Thunder SoC Family"
help
This enables support for Cavium's Thunder Family of SoCs.
+ select SATA_AHCI

config ARCH_VEXPRESS
bool "ARMv8 software model (Versatile Express)"
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 5f039f191067..8e43ccb72c95 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -52,6 +52,7 @@

enum {
AHCI_PCI_BAR_STA2X11 = 0,
+ AHCI_PCI_BAR_CAVIUM = 0,
AHCI_PCI_BAR_ENMOTUS = 2,
AHCI_PCI_BAR_STANDARD = 5,
};
@@ -483,6 +484,9 @@ static const struct pci_device_id ahci_pci_tbl[] = {
/* Enmotus */
{ PCI_DEVICE(0x1c44, 0x8000), board_ahci },

+ /* Cavium */
+ { PCI_DEVICE(0x177d, 0xa01c), .driver_data = board_ahci },
+
/* Generic, PCI class code for AHCI */
{ PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff, board_ahci },
@@ -1188,11 +1192,43 @@ static inline void ahci_gtf_filter_workaround(struct ata_host *host)
{}
#endif

+static int ahci_init_msix(struct pci_dev *pdev, unsigned int n_ports,
+ struct ahci_host_priv *hpriv)
+{
+ int rc, nvec;
+ struct msix_entry entry = {};
+
+ /* check if msix is supported */
+ nvec = pci_msix_vec_count(pdev);
+ if (nvec <= 0)
+ return 0;
+
+ /* per-port msix interrupts are not supported */
+ if (n_ports > 1 && nvec >= n_ports)
+ return -ENOSYS;
+
+ /* only enable the first entry (entry.entry = 0) */
+ rc = pci_enable_msix_exact(pdev, &entry, 1);
+ if (rc < 0)
+ return rc;
+
+ pdev->irq = entry.vector;
+
+ return 1;
+}
+
static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
struct ahci_host_priv *hpriv)
{
int rc, nvec;

+ nvec = ahci_init_msix(pdev, n_ports, hpriv);
+ if (nvec > 0)
+ return nvec;
+
+ if (nvec && nvec != -ENOSYS)
+ dev_err(&pdev->dev, "failed to enable MSI-X: %d", nvec);
+
if (hpriv->flags & AHCI_HFLAG_NO_MSI)
goto intx;

@@ -1271,11 +1307,13 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
dev_info(&pdev->dev,
"PDC42819 can only drive SATA devices with this driver\n");

- /* Both Connext and Enmotus devices use non-standard BARs */
+ /* Some devices use non-standard BARs */
if (pdev->vendor == PCI_VENDOR_ID_STMICRO && pdev->device == 0xCC06)
ahci_pci_bar = AHCI_PCI_BAR_STA2X11;
else if (pdev->vendor == 0x1c44 && pdev->device == 0x8000)
ahci_pci_bar = AHCI_PCI_BAR_ENMOTUS;
+ else if (pdev->vendor == 0x177d && pdev->device == 0xa01c)
+ ahci_pci_bar = AHCI_PCI_BAR_CAVIUM;

/*
* The JMicron chip 361/363 contains one SATA controller and one
--
2.1.3


2014-11-10 14:52:00

by Jiang Liu

[permalink] [raw]
Subject: Re: [PATCH] AHCI: Add generic MSI-X interrupt support to SATA PCI driver

On 2014/11/10 13:30, Robert Richter wrote:
> From: Sunil Goutham <[email protected]>
>
> This patch adds generic support for MSI-X interrupts to the SATA PCI
> driver. Only single interrupt support is implemented. Thus, per-port
> interrupts can not yet be enabled.
>
> The driver now checks the device for the existence of MSI-X and tries
> to enable the interrupt. Otherwise, if a device is not MSI-X capable,
> the initialization is skipped and MSI or intx interrupts are
> configured.
>
> This patch also enables AHCI for Cavium Thunder SoCs that uses MSI-X.
>
> Signed-off-by: Sunil Goutham <[email protected]>
> Signed-off-by: Robert Richter <[email protected]>
> ---
> arch/arm64/Kconfig | 1 +
> drivers/ata/ahci.c | 40 +++++++++++++++++++++++++++++++++++++++-
> 2 files changed, 40 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index ac9afde76dea..55970474d3ae 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -145,6 +145,7 @@ config ARCH_THUNDER
> bool "Cavium Inc. Thunder SoC Family"
> help
> This enables support for Cavium's Thunder Family of SoCs.
> + select SATA_AHCI
>
> config ARCH_VEXPRESS
> bool "ARMv8 software model (Versatile Express)"
> diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
> index 5f039f191067..8e43ccb72c95 100644
> --- a/drivers/ata/ahci.c
> +++ b/drivers/ata/ahci.c
> @@ -52,6 +52,7 @@
>
> enum {
> AHCI_PCI_BAR_STA2X11 = 0,
> + AHCI_PCI_BAR_CAVIUM = 0,
> AHCI_PCI_BAR_ENMOTUS = 2,
> AHCI_PCI_BAR_STANDARD = 5,
> };
> @@ -483,6 +484,9 @@ static const struct pci_device_id ahci_pci_tbl[] = {
> /* Enmotus */
> { PCI_DEVICE(0x1c44, 0x8000), board_ahci },
>
> + /* Cavium */
> + { PCI_DEVICE(0x177d, 0xa01c), .driver_data = board_ahci },
> +
> /* Generic, PCI class code for AHCI */
> { PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
> PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff, board_ahci },
> @@ -1188,11 +1192,43 @@ static inline void ahci_gtf_filter_workaround(struct ata_host *host)
> {}
> #endif
>
> +static int ahci_init_msix(struct pci_dev *pdev, unsigned int n_ports,
> + struct ahci_host_priv *hpriv)
> +{
> + int rc, nvec;
> + struct msix_entry entry = {};
> +
> + /* check if msix is supported */
> + nvec = pci_msix_vec_count(pdev);
> + if (nvec <= 0)
> + return 0;
> +
> + /* per-port msix interrupts are not supported */
> + if (n_ports > 1 && nvec >= n_ports)
> + return -ENOSYS;
> +
> + /* only enable the first entry (entry.entry = 0) */
> + rc = pci_enable_msix_exact(pdev, &entry, 1);
> + if (rc < 0)
> + return rc;
> +
> + pdev->irq = entry.vector;
Hi Robert,
You can't overwrite pci_dev->irq for MSI-X, it's no way to
recover original irq for INTx after unbinding ahci driver. Instead,
you may access msi_desc->irq when requesting irq.
Regards!
Gerry
> +
> + return 1;
> +}
> +
> static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
> struct ahci_host_priv *hpriv)
> {
> int rc, nvec;
>
> + nvec = ahci_init_msix(pdev, n_ports, hpriv);
> + if (nvec > 0)
> + return nvec;
> +
> + if (nvec && nvec != -ENOSYS)
> + dev_err(&pdev->dev, "failed to enable MSI-X: %d", nvec);
> +
> if (hpriv->flags & AHCI_HFLAG_NO_MSI)
> goto intx;
>
> @@ -1271,11 +1307,13 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
> dev_info(&pdev->dev,
> "PDC42819 can only drive SATA devices with this driver\n");
>
> - /* Both Connext and Enmotus devices use non-standard BARs */
> + /* Some devices use non-standard BARs */
> if (pdev->vendor == PCI_VENDOR_ID_STMICRO && pdev->device == 0xCC06)
> ahci_pci_bar = AHCI_PCI_BAR_STA2X11;
> else if (pdev->vendor == 0x1c44 && pdev->device == 0x8000)
> ahci_pci_bar = AHCI_PCI_BAR_ENMOTUS;
> + else if (pdev->vendor == 0x177d && pdev->device == 0xa01c)
> + ahci_pci_bar = AHCI_PCI_BAR_CAVIUM;
>
> /*
> * The JMicron chip 361/363 contains one SATA controller and one
>

2014-11-10 20:55:26

by Robert Richter

[permalink] [raw]
Subject: Re: [PATCH] AHCI: Add generic MSI-X interrupt support to SATA PCI driver

On 10.11.14 22:51:44, Jiang Liu wrote:
> On 2014/11/10 13:30, Robert Richter wrote:
> > From: Sunil Goutham <[email protected]>

> > + /* only enable the first entry (entry.entry = 0) */
> > + rc = pci_enable_msix_exact(pdev, &entry, 1);
> > + if (rc < 0)
> > + return rc;
> > +
> > + pdev->irq = entry.vector;

> You can't overwrite pci_dev->irq for MSI-X, it's no way to
> recover original irq for INTx after unbinding ahci driver. Instead,
> you may access msi_desc->irq when requesting irq.

Right, I have a version now that determines the irq vector from
pdev->msi_list.

-Robert