Re: [PATCH v2 1/2] PCI: One more parameter to pci_set_pcie_reset_state()

[Gavin Shan <gwshan@linux.vnet.ibm.com>]

On Wed, Mar 11, 2015 at 03:59:00PM +1100, Gavin Shan wrote:
>The patch adds one more parameter ("probe") to pci_set_pcie_reset_state(),
>which allows to check if one particular PCI device can be resetted by the
>function. The function will be reused to support PCI device specific methods
>maintained in pci_dev_reset_methods[] in subsequent patch.
>
>Cc: Brian King <brking@us.ibm.com>
>Cc: Frank Haverkamp <haver@linux.vnet.ibm.com>
>Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
>---

The patch depdends on: https://patchwork.ozlabs.org/patch/438598/ which
should be applied prior this one.

Thanks,
Gavin

> arch/powerpc/kernel/eeh.c       | 14 ++++++++++----
> drivers/misc/genwqe/card_base.c |  9 +++++++--
> drivers/pci/pci.c               | 15 +++++++++------
> drivers/scsi/ipr.c              |  5 +++--
> include/linux/pci.h             |  5 +++--
> 5 files changed, 32 insertions(+), 16 deletions(-)
>
>diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
>index 19a897c..60a0f15ce 100644
>--- a/arch/powerpc/kernel/eeh.c
>+++ b/arch/powerpc/kernel/eeh.c
>@@ -720,11 +720,14 @@ static void *eeh_restore_dev_state(void *data, void *userdata)
>  * pcibios_set_pcie_slot_reset - Set PCI-E reset state
>  * @dev: pci device struct
>  * @state: reset state to enter
>+ * @probe: check if the device can take the reset
>  *
>  * Return value:
>  * 	0 if success
>  */
>-int pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
>+int pcibios_set_pcie_reset_state(struct pci_dev *dev,
>+				 enum pcie_reset_state state,
>+				 int probe)
> {
> 	struct eeh_dev *edev = pci_dev_to_eeh_dev(dev);
> 	struct eeh_pe *pe = eeh_dev_to_pe(edev);
>@@ -732,9 +735,12 @@ int pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state stat
> 	if (!pe) {
> 		pr_err("%s: No PE found on PCI device %s\n",
> 			__func__, pci_name(dev));
>-		return -EINVAL;
>+		return -ENOTTY;
> 	}
>
>+	if (probe)
>+		return 0;
>+
> 	switch (state) {
> 	case pcie_deassert_reset:
> 		eeh_ops->reset(pe, EEH_RESET_DEACTIVATE);
>@@ -756,8 +762,8 @@ int pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state stat
> 		break;
> 	default:
> 		eeh_pe_state_clear(pe, EEH_PE_CFG_BLOCKED);
>-		return -EINVAL;
>-	};
>+		return -ENOTTY;
>+	}
>
> 	return 0;
> }
>diff --git a/drivers/misc/genwqe/card_base.c b/drivers/misc/genwqe/card_base.c
>index 4cf8f82..4871f69 100644
>--- a/drivers/misc/genwqe/card_base.c
>+++ b/drivers/misc/genwqe/card_base.c
>@@ -782,17 +782,22 @@ static int genwqe_pci_fundamental_reset(struct pci_dev *pci_dev)
> {
> 	int rc;
>
>+	/* Probe if the device can take the reset */
>+	rc = pci_set_pcie_reset_state(pci_dev, pcie_warm_reset, 1);
>+	if (rc)
>+		return rc;
>+
> 	/*
> 	 * lock pci config space access from userspace,
> 	 * save state and issue PCIe fundamental reset
> 	 */
> 	pci_cfg_access_lock(pci_dev);
> 	pci_save_state(pci_dev);
>-	rc = pci_set_pcie_reset_state(pci_dev, pcie_warm_reset);
>+	rc = pci_set_pcie_reset_state(pci_dev, pcie_warm_reset, 0);
> 	if (!rc) {
> 		/* keep PCIe reset asserted for 250ms */
> 		msleep(250);
>-		pci_set_pcie_reset_state(pci_dev, pcie_deassert_reset);
>+		pci_set_pcie_reset_state(pci_dev, pcie_deassert_reset, 0);
> 		/* Wait for 2s to reload flash and train the link */
> 		msleep(2000);
> 	}
>diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
>index 81f06e8..8581a5f 100644
>--- a/drivers/pci/pci.c
>+++ b/drivers/pci/pci.c
>@@ -1558,28 +1558,31 @@ EXPORT_SYMBOL(pci_disable_device);
>  * pcibios_set_pcie_reset_state - set reset state for device dev
>  * @dev: the PCIe device reset
>  * @state: Reset state to enter into
>- *
>+ * @probe: Check if the device can take the reset
>  *
>  * Sets the PCIe reset state for the device. This is the default
>  * implementation. Architecture implementations can override this.
>  */
> int __weak pcibios_set_pcie_reset_state(struct pci_dev *dev,
>-					enum pcie_reset_state state)
>+					enum pcie_reset_state state,
>+					int probe)
> {
>-	return -EINVAL;
>+	return -ENOTTY;
> }
>
> /**
>  * pci_set_pcie_reset_state - set reset state for device dev
>  * @dev: the PCIe device reset
>  * @state: Reset state to enter into
>- *
>+ * @probe: Check if the device can take the reset
>  *
>  * Sets the PCI reset state for the device.
>  */
>-int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
>+int pci_set_pcie_reset_state(struct pci_dev *dev,
>+			     enum pcie_reset_state state,
>+			     int probe)
> {
>-	return pcibios_set_pcie_reset_state(dev, state);
>+	return pcibios_set_pcie_reset_state(dev, state, probe);
> }
> EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
>
>diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
>index 9219953..89026f4 100644
>--- a/drivers/scsi/ipr.c
>+++ b/drivers/scsi/ipr.c
>@@ -8317,7 +8317,8 @@ static int ipr_reset_start_bist(struct ipr_cmnd *ipr_cmd)
> static int ipr_reset_slot_reset_done(struct ipr_cmnd *ipr_cmd)
> {
> 	ENTER;
>-	pci_set_pcie_reset_state(ipr_cmd->ioa_cfg->pdev, pcie_deassert_reset);
>+	pci_set_pcie_reset_state(ipr_cmd->ioa_cfg->pdev,
>+				 pcie_deassert_reset, 0);
> 	ipr_cmd->job_step = ipr_reset_bist_done;
> 	ipr_reset_start_timer(ipr_cmd, IPR_WAIT_FOR_BIST_TIMEOUT);
> 	LEAVE;
>@@ -8339,7 +8340,7 @@ static int ipr_reset_slot_reset(struct ipr_cmnd *ipr_cmd)
> 	struct pci_dev *pdev = ioa_cfg->pdev;
>
> 	ENTER;
>-	pci_set_pcie_reset_state(pdev, pcie_warm_reset);
>+	pci_set_pcie_reset_state(pdev, pcie_warm_reset, 0);
> 	ipr_cmd->job_step = ipr_reset_slot_reset_done;
> 	ipr_reset_start_timer(ipr_cmd, IPR_PCI_RESET_TIMEOUT);
> 	LEAVE;
>diff --git a/include/linux/pci.h b/include/linux/pci.h
>index 211e9da..c15ca2f 100644
>--- a/include/linux/pci.h
>+++ b/include/linux/pci.h
>@@ -960,7 +960,8 @@ extern unsigned int pcibios_max_latency;
> void pci_set_master(struct pci_dev *dev);
> void pci_clear_master(struct pci_dev *dev);
>
>-int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state);
>+int pci_set_pcie_reset_state(struct pci_dev *dev,
>+			     enum pcie_reset_state state, int probe);
> int pci_set_cacheline_size(struct pci_dev *dev);
> #define HAVE_PCI_SET_MWI
> int __must_check pci_set_mwi(struct pci_dev *dev);
>@@ -1647,7 +1648,7 @@ extern unsigned long pci_hotplug_mem_size;
> void pcibios_disable_device(struct pci_dev *dev);
> void pcibios_set_master(struct pci_dev *dev);
> int pcibios_set_pcie_reset_state(struct pci_dev *dev,
>-				 enum pcie_reset_state state);
>+				 enum pcie_reset_state state, int probe);
> int pcibios_add_device(struct pci_dev *dev);
> void pcibios_release_device(struct pci_dev *dev);
> void pcibios_penalize_isa_irq(int irq, int active);
>-- 
>1.8.3.2
>