From: Robert Richter <rrichter@xxxxxxxxxx>
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.
v2:
* determine irq vector from pci_dev->msi_list
Based on a patch from Sunil Goutham <sgoutham@xxxxxxxxxx>.
Signed-off-by: Robert Richter <rrichter@xxxxxxxxxx>
---
arch/arm64/Kconfig | 1 +
drivers/ata/ahci.c | 79 ++++++++++++++++++++++++++++++++++++++++++++++++++----
2 files changed, 75 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index b1f9a20a3677..2d95bbc0557e 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -157,6 +157,7 @@ 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 49f1e6890587..36c88f6d8490 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -42,6 +42,7 @@
#include <linux/device.h>
#include <linux/dmi.h>
#include <linux/gfp.h>
+#include <linux/msi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_cmnd.h>
#include <linux/libata.h>
@@ -52,6 +53,7 @@
enum {
AHCI_PCI_BAR_STA2X11 = 0,
+ AHCI_PCI_BAR_CAVIUM = 0,
AHCI_PCI_BAR_ENMOTUS = 2,
AHCI_PCI_BAR_STANDARD = 5,
};
@@ -500,6 +502,9 @@ 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 },
@@ -1202,11 +1207,41 @@ static inline void ahci_gtf_filter_workaround(struct ata_host *host)
{}
#endif
-static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
- struct ahci_host_priv *hpriv)
+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;
+
+ 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;
@@ -1250,6 +1285,35 @@ static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
return 0;
}
+static struct msi_desc *msix_get_desc(struct pci_dev *dev, u16 entry)
+{
+ struct msi_desc *desc;
+
+ list_for_each_entry(desc, &dev->msi_list, list) {
+ if (desc->msi_attrib.entry_nr == entry)
+ return desc;
+ }
+
+ return NULL;
+}
+
+static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
+ struct ahci_host_priv *hpriv)
+{
+ struct msi_desc *desc;
+
+ __ahci_init_interrupts(pdev, n_ports, hpriv);
+
+ if (!pdev->msix_enabled)
+ return pdev->irq;
+
+ desc = msix_get_desc(pdev, 0); /* first entry */
+ if (!desc)
+ return -ENODEV;
+
+ return desc->irq;
+}
+
static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
{
unsigned int board_id = ent->driver_data;
@@ -1260,6 +1324,7 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
struct ata_host *host;
int n_ports, i, rc;
int ahci_pci_bar = AHCI_PCI_BAR_STANDARD;
+ int irq;
VPRINTK("ENTER\n");
@@ -1285,11 +1350,13 @@ 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
@@ -1411,7 +1478,9 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
*/
n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));
- ahci_init_interrupts(pdev, n_ports, hpriv);
+ irq = ahci_init_interrupts(pdev, n_ports, hpriv);
+ if (irq < 0)
+ return irq;
host = ata_host_alloc_pinfo(&pdev->dev, ppi, n_ports);
if (!host)
@@ -1463,7 +1532,7 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
pci_set_master(pdev);
- return ahci_host_activate(host, pdev->irq, &ahci_sht);
+ return ahci_host_activate(host, irq, &ahci_sht);
}
module_pci_driver(ahci_pci_driver);
--
2.1.1
--
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