accel/qaic: Allocate an exact number of MSIs

Devices use 1 MSI vector for the MHI controller and as many vectors as
the DMA bridge channels on the device. During the probing of the
device, the driver allocates 32 MSI vectors, which is usually more
than what is needed for AIC100 devices, which is wasting resources.

Allocate only the needed number of MSI vectors per device.

Signed-off-by: Youssef Samir <quic_yabdulra@quicinc.com>
Reviewed-by: Troy Hanson <quic_thanson@quicinc.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250117170943.2643280-4-quic_jhugo@quicinc.com

diff --git a/drivers/accel/qaic/qaic_drv.c b/drivers/accel/qaic/qaic_drv.c
index 81819b9ef8d4fd148d1e85a1ad57d987a5cc199f..6e9bed17b3f14f6d9232f0de595eec388eaba68e 100644 (file)
--- a/drivers/accel/qaic/qaic_drv.c
+++ b/drivers/accel/qaic/qaic_drv.c
@@ -465,12 +465,13 @@ static int init_pci(struct qaic_device *qdev, struct pci_dev *pdev)
 
 static int init_msi(struct qaic_device *qdev, struct pci_dev *pdev)
 {
+       int irq_count = qdev->num_dbc + 1;
        int mhi_irq;
        int ret;
        int i;
 
        /* Managed release since we use pcim_enable_device */
-       ret = pci_alloc_irq_vectors(pdev, 32, 32, PCI_IRQ_MSI);
+       ret = pci_alloc_irq_vectors(pdev, irq_count, irq_count, PCI_IRQ_MSI);
        if (ret == -ENOSPC) {
                ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
                if (ret < 0)
@@ -485,7 +486,8 @@ static int init_msi(struct qaic_device *qdev, struct pci_dev *pdev)
                 * interrupted, it shouldn't race with itself.
                 */
                qdev->single_msi = true;
-               pci_info(pdev, "Allocating 32 MSIs failed, operating in 1 MSI mode. Performance may be impacted.\n");
+               pci_info(pdev, "Allocating %d MSIs failed, operating in 1 MSI mode. Performance may be impacted.\n",
+                        irq_count);
        } else if (ret < 0) {
                return ret;
        }