Commit 1b66601d authored by Kang Yang's avatar Kang Yang Committed by Kalle Valo
Browse files

wifi: ath12k: get msi_data again after request_irq is called 



The reservation mode of interrupts in kernel assigns a dummy vector
when the interrupt is allocated and assigns a real vector when the
request_irq is called. The reservation mode helps to ease vector
pressure when devices with a large amount of queues/interrupts are
initialized, but only a minimal subset of those queues/interrupts
is actually used.

So on reservation mode, the msi_data may change after request_irq is
called, then it will lead to spurious interrupt. But when VT-d in
BIOS is enabled and ath12k can get 32 MSI vectors, ath12k always get
the same msi_data before and after request_irq.

So in case of one MSI vector, ath12k need read msi_data again after
request_irq is called, and then the correct msi_data is programmed
into WCN7850 hardware components.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0-03427-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.15378.4

Signed-off-by: default avatarKang Yang <quic_kangyang@quicinc.com>
Acked-by: default avatarJeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: default avatarKalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20231121021304.12966-2-quic_kangyang@quicinc.com
parent 8cc18a70

drivers/net/wireless/ath/ath12k/pci.c

+30 −0
Original line number Diff line number Diff line
@@ -708,6 +708,25 @@ static void ath12k_pci_msi_free(struct ath12k_pci *ab_pci) 
	pci_free_irq_vectors(ab_pci->pdev);

}



static int ath12k_pci_config_msi_data(struct ath12k_pci *ab_pci)

{

	struct msi_desc *msi_desc;



	msi_desc = irq_get_msi_desc(ab_pci->pdev->irq);

	if (!msi_desc) {

		ath12k_err(ab_pci->ab, "msi_desc is NULL!\n");

		pci_free_irq_vectors(ab_pci->pdev);

		return -EINVAL;

	}



	ab_pci->msi_ep_base_data = msi_desc->msg.data;



	ath12k_dbg(ab_pci->ab, ATH12K_DBG_PCI, "pci after request_irq msi_ep_base_data %d\n",

		   ab_pci->msi_ep_base_data);



	return 0;

}



static int ath12k_pci_claim(struct ath12k_pci *ab_pci, struct pci_dev *pdev)

{

	struct ath12k_base *ab = ab_pci->ab;
@@ -1286,6 +1305,17 @@ static int ath12k_pci_probe(struct pci_dev *pdev, 
		goto err_ce_free;

	}



	/* kernel may allocate a dummy vector before request_irq and

	 * then allocate a real vector when request_irq is called.

	 * So get msi_data here again to avoid spurious interrupt

	 * as msi_data will configured to srngs.

	 */

	ret = ath12k_pci_config_msi_data(ab_pci);

	if (ret) {

		ath12k_err(ab, "failed to config msi_data: %d\n", ret);

		goto err_free_irq;

	}



	ret = ath12k_core_init(ab);

	if (ret) {

		ath12k_err(ab, "failed to init core: %d\n", ret);