Subject: Re: [PATCH V2 5/6] powerpc/powernv: boundary the total vf bar size instead of the individual one

From: Wei Yang <[email-masked]>
Date: Thu, 6 Aug 2015 22:03:04 +0800

On Thu, Aug 06, 2015 at 03:28:51PM +1000, Gavin Shan wrote:
>On Wed, Aug 05, 2015 at 09:25:02AM +0800, Wei Yang wrote:
>>Each VF could have 6 BARs at most. When the total BAR size exceeds the
>>gate, after expanding it will also exhaust the M64 Window.
>>
>>This patch limits the boundary by checking the total VF BAR size instead of
>>the individual BAR.
>>
>>Signed-off-by: Wei Yang <[email-masked]>
>
>Ok. I didn't look at this when giving comments to last patch. It turns
>you have the change in this patch. Please merge it with the previous
>patch.
>

Hmm... I prefer to have them in two patches. One focus on the calculation of
gate and the other focus on checking the total VF BAR size. This would help
record the change.

>>---
>> arch/powerpc/platforms/powernv/pci-ioda.c |   13 +++++++------
>> 1 file changed, 7 insertions(+), 6 deletions(-)
>>
>>diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
>>index 31dcedc..4042303 100644
>>--- a/arch/powerpc/platforms/powernv/pci-ioda.c
>>+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
>>@@ -2702,7 +2702,7 @@ static void pnv_pci_ioda_fixup_iov_resources(struct pci_dev *pdev)
>> 	struct pnv_phb *phb;
>> 	struct resource *res;
>> 	int i;
>>-	resource_size_t size, gate;
>>+	resource_size_t size, gate, total_vf_bar_sz;
>> 	struct pci_dn *pdn;
>> 	int mul, total_vfs;
>>
>>@@ -2729,6 +2729,7 @@ static void pnv_pci_ioda_fixup_iov_resources(struct pci_dev *pdev)
>> 	 * Window and limit the system flexibility.
>> 	 */
>> 	gate = phb->ioda.m64_segsize >> 1;
>>+	total_vf_bar_sz = 0;
>>
>> 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
>> 		res = &pdev->resource[i + PCI_IOV_RESOURCES];
>>@@ -2741,13 +2742,13 @@ static void pnv_pci_ioda_fixup_iov_resources(struct pci_dev *pdev)
>> 			return;
>> 		}
>>
>>-		size = pci_iov_resource_size(pdev, i + PCI_IOV_RESOURCES);
>>+		total_vf_bar_sz += pci_iov_resource_size(pdev,
>>+				i + PCI_IOV_RESOURCES);
>>
>> 		/* bigger than or equal to gate */
>>-		if (size >= gate) {
>>-			dev_info(&pdev->dev, "PowerNV: VF BAR%d: %pR IOV size "
>>-				"is bigger than %lld, roundup power2\n",
>>-				 i, res, gate);
>>+		if (total_vf_bar_sz >= gate) {
>>+			dev_info(&pdev->dev, "PowerNV: VF BAR Total IOV size "
>>+				"is bigger than %lld, roundup power2\n", gate);
>> 			mul = roundup_pow_of_two(total_vfs);
>> 			pdn->m64_single_mode = true;
>> 			break;
>>-- 
>>1.7.9.5
>>

-- 
Richard Yang
Help you, Help me