[PATCH v2] net/axgbe: use PCI root complex device to distinguish AMD hardware

[Namburu, Chandu-babu]

[Public]

Hi David Marchand,

I have submitted v2 patch with your suggestion in git log. Please review changes.

Regards,
Chandu

-----Original Message-----
From: Namburu, Chandu-babu <chandu at amd.com> 
Sent: Thursday, December 2, 2021 9:41 PM
To: dev at dpdk.org; david.marchand at redhat.com
Cc: Sebastian, Selwin <Selwin.Sebastian at amd.com>; Arsalan_Awan at mentor.com; ferruh.yigit at intel.com; Namburu, Chandu-babu <chandu at amd.com>; stable at dpdk.org
Subject: [PATCH v2] net/axgbe: use PCI root complex device to distinguish AMD hardware

"bus/pci: optimize bus scan" broke axgbe on V1000/R1000.
RV root complex pci device does not have any kernel driver assigned so it is removed from pci scan list which is used in
"net/axgbe: add a HW quirk for register definitions".

Get root complex device id directly from pci sysfs instead of pci scan list.

Fixes: 991e0b1dbc4a (net/axgbe: add a HW quirk for register definitions)
Cc: stable at dpdk.org

Signed-off-by: Chandubabu Namburu <chandu at amd.com>
---
 drivers/net/axgbe/axgbe_ethdev.c | 39 ++++++++++++++++----------------
 1 file changed, 20 insertions(+), 19 deletions(-)

diff --git a/drivers/net/axgbe/axgbe_ethdev.c b/drivers/net/axgbe/axgbe_ethdev.c
index 7d40c18a86..7b8d94ca3c 100644
--- a/drivers/net/axgbe/axgbe_ethdev.c
+++ b/drivers/net/axgbe/axgbe_ethdev.c
@@ -10,6 +10,8 @@
 #include "axgbe_regs.h"
 #include "rte_time.h"
 
+#include "eal_filesystem.h"
+
 static int eth_axgbe_dev_init(struct rte_eth_dev *eth_dev);  static int  axgbe_dev_configure(struct rte_eth_dev *dev);  static int  axgbe_dev_start(struct rte_eth_dev *dev); @@ -2117,28 +2119,27 @@ static void axgbe_default_config(struct axgbe_port *pdata)
 	pdata->power_down = 0;
 }
 
-static int
-pci_device_cmp(const struct rte_device *dev, const void *_pci_id)
+/*
+ * Return PCI root complex device id on success else 0  */ static 
+uint16_t
+get_pci_rc_devid(void)
 {
-	const struct rte_pci_device *pdev = RTE_DEV_TO_PCI_CONST(dev);
-	const struct rte_pci_id *pcid = _pci_id;
+	char pci_sysfs[PATH_MAX];
+	const struct rte_pci_addr pci_rc_addr = {0, 0, 0, 0};
+	unsigned long device_id;
 
-	if (pdev->id.vendor_id == AMD_PCI_VENDOR_ID &&
-			pdev->id.device_id == pcid->device_id)
-		return 0;
-	return 1;
-}
+	snprintf(pci_sysfs, sizeof(pci_sysfs), "%s/" PCI_PRI_FMT "/device",
+		 rte_pci_get_sysfs_path(), pci_rc_addr.domain,
+		 pci_rc_addr.bus, pci_rc_addr.devid, pci_rc_addr.function);
 
-static bool
-pci_search_device(int device_id)
-{
-	struct rte_bus *pci_bus;
-	struct rte_pci_id dev_id;
+	/* get device id */
+	if (eal_parse_sysfs_value(pci_sysfs, &device_id) < 0) {
+		PMD_INIT_LOG(ERR, "Error in reading PCI sysfs\n");
+		return 0;
+	}
 
-	dev_id.device_id = device_id;
-	pci_bus = rte_bus_find_by_name("pci");
-	return (pci_bus != NULL) &&
-		(pci_bus->find_device(NULL, pci_device_cmp, &dev_id) != NULL);
+	return (uint16_t)device_id;
 }
 
 /*
@@ -2180,7 +2181,7 @@ eth_axgbe_dev_init(struct rte_eth_dev *eth_dev)
 	/*
 	 * Use root complex device ID to differentiate RV AXGBE vs SNOWY AXGBE
 	 */
-	if (pci_search_device(AMD_PCI_RV_ROOT_COMPLEX_ID)) {
+	if ((get_pci_rc_devid()) == AMD_PCI_RV_ROOT_COMPLEX_ID) {
 		pdata->xpcs_window_def_reg = PCS_V2_RV_WINDOW_DEF;
 		pdata->xpcs_window_sel_reg = PCS_V2_RV_WINDOW_SELECT;
 	} else {
--
2.25.1