Subject: Re: [RFC PATCH V3 11/17] ppc/pnv: Expand VF resources according to the number of total_pe

From: Wei Yang <[email-masked]>
Date: Mon, 23 Jun 2014 14:56:52 +0800

On Mon, Jun 23, 2014 at 04:07:07PM +1000, Gavin Shan wrote:
>On Tue, Jun 10, 2014 at 09:56:33AM +0800, Wei Yang wrote:
>>On PHB3, VF resources will be covered by M64 BAR to have better PE isolation.
>>Mostly the total_pe number is different from the total_VFs, which will lead to
>>a conflict between MMIO space and the PE number.
>>
>>This patch expands the VF resource size to reserve total_pe number of VFs'
>>resource, which prevents the conflict.
>>
>>Signed-off-by: Wei Yang <[email-masked]>
>>---
>> arch/powerpc/include/asm/machdep.h        |    6 +++
>> arch/powerpc/include/asm/pci-bridge.h     |    3 ++
>> arch/powerpc/kernel/pci-common.c          |   15 ++++++
>> arch/powerpc/platforms/powernv/pci-ioda.c |   83 +++++++++++++++++++++++++++++
>> 4 files changed, 107 insertions(+)
>>
>>diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h
>>index ad3025d..2f2e770 100644
>>--- a/arch/powerpc/include/asm/machdep.h
>>+++ b/arch/powerpc/include/asm/machdep.h
>>@@ -234,9 +234,15 @@ struct machdep_calls {
>>
>> 	/* Called after scan and before resource survey */
>> 	void (*pcibios_fixup_phb)(struct pci_controller *hose);
>>+#ifdef CONFIG_PCI_IOV
>>+	void (*pcibios_fixup_sriov)(struct pci_bus *bus);
>>+#endif /* CONFIG_PCI_IOV */
>>
>> 	/* Called during PCI resource reassignment */
>> 	resource_size_t (*pcibios_window_alignment)(struct pci_bus *, unsigned long type);
>>+#ifdef CONFIG_PCI_IOV
>>+	resource_size_t (*__pci_sriov_resource_size)(struct pci_dev *, int resno);
>
>	resource_size_t (*pcibios_sriov_resource_size)(struct pci_dev *, int resno);
>
>You probably can put all SRIOV related functions together:
>
>#ifdef CONFIG_PCI_IOV
>	func_a;
>	func_b;
>	 :
>#endif
>
>>+#endif /* CONFIG_PCI_IOV */
>>
>> 	/* Called to shutdown machine specific hardware not already controlled
>> 	 * by other drivers.
>>diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
>>index 4ca90a3..8c849d8 100644
>>--- a/arch/powerpc/include/asm/pci-bridge.h
>>+++ b/arch/powerpc/include/asm/pci-bridge.h
>>@@ -168,6 +168,9 @@ struct pci_dn {
>> #define IODA_INVALID_PE		(-1)
>> #ifdef CONFIG_PPC_POWERNV
>> 	int	pe_number;
>>+#ifdef CONFIG_PCI_IOV
>>+	u16     vfs;
>>+#endif /* CONFIG_PCI_IOV */
>> #endif
>> };
>>
>>diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
>>index c449a26..c4e2e92 100644
>>--- a/arch/powerpc/kernel/pci-common.c
>>+++ b/arch/powerpc/kernel/pci-common.c
>>@@ -120,6 +120,16 @@ resource_size_t pcibios_window_alignment(struct pci_bus *bus,
>> 	return 1;
>> }
>>
>>+#ifdef CONFIG_PCI_IOV
>>+resource_size_t pcibios_sriov_resource_size(struct pci_dev *pdev, int resno)
>>+{
>>+	if (ppc_md.__pci_sriov_resource_size)
>>+		return ppc_md.__pci_sriov_resource_size(pdev, resno);
>>+
>>+	return 0;
>>+}
>>+#endif /* CONFIG_PCI_IOV */
>>+
>> static resource_size_t pcibios_io_size(const struct pci_controller *hose)
>> {
>> #ifdef CONFIG_PPC64
>>@@ -1675,6 +1685,11 @@ void pcibios_scan_phb(struct pci_controller *hose)
>> 	if (ppc_md.pcibios_fixup_phb)
>> 		ppc_md.pcibios_fixup_phb(hose);
>>
>>+#ifdef CONFIG_PCI_IOV
>>+	if (ppc_md.pcibios_fixup_sriov)
>>+		ppc_md.pcibios_fixup_sriov(bus);
>
>One question I probably asked before: why we can't put the logic
>of ppc_md.pcibios_fixup_sriov() to ppc_md.pcibios_fixup_phb()?
>

Yep, you have asked before and I replied before too :-)

During EEH hotplug, if the PF are removed, the IOV BAR will be retrieved from
the device itself again. If I merge this fixup into
ppc_md.pcibios_fixup_phb(), this is not proper to be invoked at hotplug event.

Or fixup the phb during EEH hotplug is reasonable?

-- 
Richard Yang
Help you, Help me