[v16,7/9] PCI/DPC: Export DPC error recovery functions

Commit Message

Kuppuswamy Sathyanarayanan Feb. 28, 2020, 12:59 a.m. UTC

From: Kuppuswamy Sathyanarayanan <[e-mail]>

This is a preparatory patch for adding EDR support.

As per the Downstream Port Containment Related Enhancements ECN to the
PCI Firmware Specification r3.2, sec 4.5.1, table 4-6, If DPC is
controlled by firmware, firmware is responsible for initializing
Downstream Port Containment Extended Capability Structures per firmware
policy. Further, the OS is permitted to read or write DPC Control and
Status registers of a port while processing an Error Disconnect Recover
notification from firmware on that port.

To add EDR support we need to re-use DPC error handling functions. So
add necessary interfaces.

Signed-off-by: Kuppuswamy Sathyanarayanan <[e-mail]>
---
 drivers/pci/pci.h      |  2 ++
 drivers/pci/pcie/dpc.c | 12 +++++++++---
 2 files changed, 11 insertions(+), 3 deletions(-)

Comments

Christoph Hellwig March 5, 2020, 4:37 p.m. UTC | #1

Please fix your subject.  Nothing is being exported in this patch.

Kuppuswamy Sathyanarayanan March 5, 2020, 5:42 p.m. UTC | #2

Hi,

On 3/5/20 8:37 AM, Christoph Hellwig wrote:
> Please fix your subject.  Nothing is being exported in this patch.
I will do it. I meant it as its being used outside dpc..

Bjorn Helgaas March 5, 2020, 6:59 p.m. UTC | #3

On Thu, Mar 05, 2020 at 09:42:21AM -0800, Kuppuswamy Sathyanarayanan wrote:
> Hi,
> 
> On 3/5/20 8:37 AM, Christoph Hellwig wrote:
> > Please fix your subject.  Nothing is being exported in this patch.
> I will do it. I meant it as its being used outside dpc..

I'll update this.  I have some other tweaks so I'll post an updated
series soon.

Kuppuswamy Sathyanarayanan March 5, 2020, 7:22 p.m. UTC | #4

Hi Bjorn,

On 3/5/20 10:59 AM, Bjorn Helgaas wrote:
> On Thu, Mar 05, 2020 at 09:42:21AM -0800, Kuppuswamy Sathyanarayanan wrote:
>> Hi,
>>
>> On 3/5/20 8:37 AM, Christoph Hellwig wrote:
>>> Please fix your subject.  Nothing is being exported in this patch.
>> I will do it. I meant it as its being used outside dpc..
> I'll update this.  I have some other tweaks so I'll post an updated
> series soon.
In case if you haven't noticed, I have posted v17 version of it. please 
apply
your changes on top of it.

Patch

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index c239e6dd2542..a475192c553a 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -449,6 +449,8 @@  void aer_print_error(struct pci_dev *dev, struct aer_err_info *info);
 void pci_save_dpc_state(struct pci_dev *dev);
 void pci_restore_dpc_state(struct pci_dev *dev);
 void pci_dpc_init(struct pci_dev *pdev);
+void dpc_process_error(struct pci_dev *pdev);
+pci_ers_result_t dpc_reset_link(struct pci_dev *pdev);
 #else
 static inline void pci_save_dpc_state(struct pci_dev *dev) {}
 static inline void pci_restore_dpc_state(struct pci_dev *dev) {}
diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
index 57e7f94b98cf..e0a5b5f9547f 100644
--- a/drivers/pci/pcie/dpc.c
+++ b/drivers/pci/pcie/dpc.c
@@ -89,7 +89,7 @@  static int dpc_wait_rp_inactive(struct pci_dev *pdev)
 	return 0;
 }
 
-static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev)
+pci_ers_result_t dpc_reset_link(struct pci_dev *pdev)
 {
 	u16 cap;
 
@@ -193,9 +193,8 @@  static int dpc_get_aer_uncorrect_severity(struct pci_dev *dev,
 	return 1;
 }
 
-static irqreturn_t dpc_handler(int irq, void *context)
+void dpc_process_error(struct pci_dev *pdev)
 {
-	struct pci_dev *pdev = context;
 	u16 cap = pdev->dpc_cap, status, source, reason, ext_reason;
 	struct aer_err_info info;
 
@@ -225,6 +224,13 @@  static irqreturn_t dpc_handler(int irq, void *context)
 		pci_cleanup_aer_uncorrect_error_status(pdev);
 		pci_aer_clear_fatal_status(pdev);
 	}
+}
+
+static irqreturn_t dpc_handler(int irq, void *context)
+{
+	struct pci_dev *pdev = context;
+
+	dpc_process_error(pdev);
 
 	/* We configure DPC so it only triggers on ERR_FATAL */
 	pcie_do_recovery(pdev, pci_channel_io_frozen, dpc_reset_link);