On Sun, Nov 20, 2022 Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> wrote:
>
> Some SoCs may only support 1 RC with a few MSIs support that the total numver of MSIs is
> less than MAX_MSI_IRQS_PER_CTRL. In this case, num_ctrls will be zero which fails setting
> up MSI support. Fix it by rounding up num_ctrls to at least one.
Hi Shawn Lin,
If you find only a single case (1RC with a few MSIs), please set it as one
if the divided value is zero.
For example,
num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
if (num_ctrls < 1)
num_ctrls = 1
Best regards,
Jingoo Han
>
> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
> ---
>
> drivers/pci/controller/dwc/pcie-designware-host.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index 39f3b37..2cba2a8 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -61,7 +61,7 @@ irqreturn_t dw_handle_msi_irq(struct dw_pcie_rp *pp)
> irqreturn_t ret = IRQ_NONE;
> struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
>
> - num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
> + num_ctrls = DIV_ROUND_UP(pp->num_vectors, MAX_MSI_IRQS_PER_CTRL);
>
> for (i = 0; i < num_ctrls; i++) {
> status = dw_pcie_readl_dbi(pci, PCIE_MSI_INTR0_STATUS +
> @@ -342,7 +342,7 @@ static int dw_pcie_msi_host_init(struct dw_pcie_rp *pp)
>
> if (!pp->num_vectors)
> pp->num_vectors = MSI_DEF_NUM_VECTORS;
> - num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
> + num_ctrls = DIV_ROUND_UP(pp->num_vectors, MAX_MSI_IRQS_PER_CTRL);
>
> if (!pp->msi_irq[0]) {
> pp->msi_irq[0] = platform_get_irq_byname_optional(pdev, "msi");
> @@ -706,7 +706,7 @@ int dw_pcie_setup_rc(struct dw_pcie_rp *pp)
> dw_pcie_setup(pci);
>
> if (pp->has_msi_ctrl) {
> - num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
> + num_ctrls = DIV_ROUND_UP(pp->num_vectors, MAX_MSI_IRQS_PER_CTRL);
>
> /* Initialize IRQ Status array */
> for (ctrl = 0; ctrl < num_ctrls; ctrl++) {
> --
> 2.7.4
>
