diff mbox series

PCI: dwc: Round up num_ctrls if num_vectors is less than MAX_MSI_IRQS_PER_CTRL

Message ID 1669014996-177686-1-git-send-email-shawn.lin@rock-chips.com (mailing list archive)
State Superseded
Headers show
Series PCI: dwc: Round up num_ctrls if num_vectors is less than MAX_MSI_IRQS_PER_CTRL | expand

Commit Message

Shawn Lin Nov. 21, 2022, 7:16 a.m. UTC
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.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
---

 drivers/pci/controller/dwc/pcie-designware-host.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Han Jingoo Nov. 21, 2022, 11:54 p.m. UTC | #1
On Sun, Nov 20, 2022 Shawn Lin <shawn.lin@rock-chips.com> 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@rock-chips.com>
> ---
>
>  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
>
Shawn Lin Nov. 22, 2022, 1:16 a.m. UTC | #2
On 2022/11/22 7:54, Han Jingoo wrote:
> On Sun, Nov 20, 2022 Shawn Lin <shawn.lin@rock-chips.com> 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.
> 

Yes we have one such platform. Will set it to one as your comment.

Thanks.

> 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@rock-chips.com>
>> ---
>>
>>   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
>>
diff mbox series

Patch

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++) {