diff mbox series

[v2,2/4] cxl/pci: Define a common function get_cxl_devstate()

Message ID 20241001005234.61409-3-Smita.KoralahalliChannabasappa@amd.com
State New
Headers show
Series acpi/ghes, cper, cxl: Trace FW-First CXL Protocol Errors | expand

Commit Message

Smita Koralahalli Oct. 1, 2024, 12:52 a.m. UTC
Refactor computation of cxlds to a common function get_cxl_devstate().

The above function could then be reused in both FW-First Component and
Protocol error reporting and handling.

Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
---
v2:
	Refactor before adding trace support.
	get_cxl_dev() -> get_cxl_devstate().
	Cleaned up get_cxl_devstate().
---
 drivers/cxl/pci.c | 32 +++++++++++++++++++-------------
 1 file changed, 19 insertions(+), 13 deletions(-)

Comments

Dan Williams Oct. 2, 2024, 11:04 p.m. UTC | #1
Smita Koralahalli wrote:
> Refactor computation of cxlds to a common function get_cxl_devstate().
> 
> The above function could then be reused in both FW-First Component and
> Protocol error reporting and handling.

Ira caught the bug in the cleanup conversion, but I am otherwise not
convinced there would be much reuse for a helper like this given any
endpoint-flagged protocol errors would reuse the common
cxl_handle_cper_event(), unless I am missing something?
Smita Koralahalli Oct. 3, 2024, 6:44 p.m. UTC | #2
On 10/2/2024 4:04 PM, Dan Williams wrote:
> Smita Koralahalli wrote:
>> Refactor computation of cxlds to a common function get_cxl_devstate().
>>
>> The above function could then be reused in both FW-First Component and
>> Protocol error reporting and handling.
> 
> Ira caught the bug in the cleanup conversion, but I am otherwise not
> convinced there would be much reuse for a helper like this given any
> endpoint-flagged protocol errors would reuse the common
> cxl_handle_cper_event(), unless I am missing something?
> 

Yeah, the only intent was to not redo the BDF decoding at two places. I 
don't see a problem in calling cxl_handle_prot_err() inside 
cxl_handle_cper_event() as Ira suggested in 4/4.

However, I think all of this would fall off if we isolate protocol 
errors from cxl_cper_fifo and handle them separately.

Thanks
Smita
diff mbox series

Patch

diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index 37164174b5fb..915102f5113f 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -1021,32 +1021,38 @@  static struct pci_driver cxl_pci_driver = {
 	},
 };
 
+static struct cxl_dev_state *get_cxl_devstate(u16 segment, u8 bus,
+					      u8 device, u8 function)
+{
+	unsigned int devfn = PCI_DEVFN(device, function);
+	struct pci_dev *pdev __free(pci_dev_put) =
+		pci_get_domain_bus_and_slot(segment, bus, devfn);
+
+	if (!pdev)
+		return NULL;
+
+	guard(device)(&pdev->dev);
+	if (pdev->driver != &cxl_pci_driver)
+		return NULL;
+
+	return pci_get_drvdata(pdev);
+}
+
 #define CXL_EVENT_HDR_FLAGS_REC_SEVERITY GENMASK(1, 0)
 static void cxl_handle_cper_event(enum cxl_event_type ev_type,
 				  struct cxl_cper_event_rec *rec)
 {
 	struct cper_cxl_event_devid *device_id = &rec->hdr.device_id;
-	struct pci_dev *pdev __free(pci_dev_put) = NULL;
 	enum cxl_event_log_type log_type;
 	struct cxl_dev_state *cxlds;
-	unsigned int devfn;
 	u32 hdr_flags;
 
 	pr_debug("CPER event %d for device %u:%u:%u.%u\n", ev_type,
 		 device_id->segment_num, device_id->bus_num,
 		 device_id->device_num, device_id->func_num);
 
-	devfn = PCI_DEVFN(device_id->device_num, device_id->func_num);
-	pdev = pci_get_domain_bus_and_slot(device_id->segment_num,
-					   device_id->bus_num, devfn);
-	if (!pdev)
-		return;
-
-	guard(device)(&pdev->dev);
-	if (pdev->driver != &cxl_pci_driver)
-		return;
-
-	cxlds = pci_get_drvdata(pdev);
+	cxlds = get_cxl_devstate(device_id->segment_num, device_id->bus_num,
+				 device_id->device_num, device_id->func_num);
 	if (!cxlds)
 		return;