Re: [PATCH v7 18/50] powerpc/powernv: Remove DMA32 PE list

Gavin Shan
2015-11-17T02:02:45Z

On Tue, Nov 17, 2015 at 12:54:04PM +1100, Alexey Kardashevskiy wrote:
>On 11/05/2015 12:12 AM, Gavin Shan wrote:
>>PEs are put into PHB DMA32 list (phb->ioda.pe_dma_list) according
>>to their DMA32 weight. The PEs on the list are iterated to setup
>>their TCE32 tables at system booting time. The list is used for
>>once and there is no good reason for it to survive.
>
>From the above I concluded that you need a list, just do not need to keep
>after the configuration is done but in fact you remove the list completely so
>just remove "to survive" (s/for it to survive/for keep having it/) :)
>

Thanks & will change it accordingly in next revision :)

>>
>>This moves the logic calculating DMA32 weight of PHB and PE to
>>pnv_pci_ioda1_setup_dma() to drop PHB's DMA32 list.
>>
>>Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
>>---
>> arch/powerpc/platforms/powernv/pci-ioda.c | 150 ++++++++++++++----------------
>> arch/powerpc/platforms/powernv/pci.h | 19 ----
>> 2 files changed, 68 insertions(+), 101 deletions(-)
>>
>>diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
>>index 4c2e023..20ebe6e 100644
>>--- a/arch/powerpc/platforms/powernv/pci-ioda.c
>>+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
>>@@ -891,44 +891,6 @@ out:
>> return 0;
>> }
>>
>>-static void pnv_ioda_link_pe_by_weight(struct pnv_phb *phb,
>>- struct pnv_ioda_pe *pe)
>>-{
>>- struct pnv_ioda_pe *lpe;
>>-
>>- list_for_each_entry(lpe, &phb->ioda.pe_dma_list, dma_link) {
>>- if (lpe->dma_weight < pe->dma_weight) {
>>- list_add_tail(&pe->dma_link, &lpe->dma_link);
>>- return;
>>- }
>>- }
>>- list_add_tail(&pe->dma_link, &phb->ioda.pe_dma_list);
>>-}
>>-
>>-static unsigned int pnv_ioda_dma_weight(struct pci_dev *dev)
>>-{
>>- /* This is quite simplistic. The "base" weight of a device
>>- * is 10. 0 means no DMA is to be accounted for it.
>>- */
>>-
>>- /* If it's a bridge, no DMA */
>>- if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL)
>>- return 0;
>>-
>>- /* Reduce the weight of slow USB controllers */
>>- if (dev->class == PCI_CLASS_SERIAL_USB_UHCI ||
>>- dev->class == PCI_CLASS_SERIAL_USB_OHCI ||
>>- dev->class == PCI_CLASS_SERIAL_USB_EHCI)
>>- return 3;
>>-
>>- /* Increase the weight of RAID (includes Obsidian) */
>>- if ((dev->class >> 8) == PCI_CLASS_STORAGE_RAID)
>>- return 15;
>>-
>>- /* Default */
>>- return 10;
>>-}
>>-
>> #ifdef CONFIG_PCI_IOV
>> static int pnv_pci_vf_resource_shift(struct pci_dev *dev, int offset)
>> {
>>@@ -1009,7 +971,6 @@ static void pnv_ioda_setup_same_PE(struct pci_bus *bus, struct pnv_ioda_pe *pe)
>> continue;
>> }
>> pdn->pe_number = pe->pe_number;
>>- pe->dma_weight += pnv_ioda_dma_weight(dev);
>> if ((pe->flags & PNV_IODA_PE_BUS_ALL) && dev->subordinate)
>> pnv_ioda_setup_same_PE(dev->subordinate, pe);
>> }
>>@@ -1046,10 +1007,8 @@ static void pnv_ioda_setup_bus_PE(struct pci_bus *bus, bool all)
>> pe->flags |= (all ? PNV_IODA_PE_BUS_ALL : PNV_IODA_PE_BUS);
>> pe->pbus = bus;
>> pe->pdev = NULL;
>>- pe->tce32_seg = -1;
>> pe->mve_number = -1;
>> pe->rid = bus->busn_res.start << 8;
>>- pe->dma_weight = 0;
>>
>> if (all)
>> pe_info(pe, "Secondary bus %d..%d associated with PE#%d\n",
>>@@ -1071,17 +1030,6 @@ static void pnv_ioda_setup_bus_PE(struct pci_bus *bus, bool all)
>>
>> /* Put PE to the list */
>> list_add_tail(&pe->list, &phb->ioda.pe_list);
>>-
>>- /* Account for one DMA PE if at least one DMA capable device exist
>>- * below the bridge
>>- */
>>- if (pe->dma_weight != 0) {
>>- phb->ioda.dma_weight += pe->dma_weight;
>>- phb->ioda.dma_pe_count++;
>>- }
>>-
>>- /* Link the PE */
>>- pnv_ioda_link_pe_by_weight(phb, pe);
>> }
>>
>> static void pnv_ioda_setup_PEs(struct pci_bus *bus)
>>@@ -1389,7 +1337,6 @@ static void pnv_ioda_setup_vf_PE(struct pci_dev *pdev, u16 num_vfs)
>> pe->flags = PNV_IODA_PE_VF;
>> pe->pbus = NULL;
>> pe->parent_dev = pdev;
>>- pe->tce32_seg = -1;
>> pe->mve_number = -1;
>> pe->rid = (pci_iov_virtfn_bus(pdev, vf_index) << 8) |
>> pci_iov_virtfn_devfn(pdev, vf_index);
>>@@ -1842,6 +1789,47 @@ static struct iommu_table_ops pnv_ioda2_iommu_ops = {
>> .free = pnv_ioda2_table_free,
>> };
>>
>>+static int pnv_pci_ioda_dev_dma_weight(struct pci_dev *dev, void *data)
>>+{
>>+ unsigned int *weight = (unsigned int *)data;
>>+
>>+ /* This is quite simplistic. The "base" weight of a device
>>+ * is 10. 0 means no DMA is to be accounted for it.
>>+ */
>>+
>>+ if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL)
>>+ return 0;
>>+
>>+ if (dev->class == PCI_CLASS_SERIAL_USB_UHCI ||
>>+ dev->class == PCI_CLASS_SERIAL_USB_OHCI ||
>>+ dev->class == PCI_CLASS_SERIAL_USB_EHCI)
>>+ *weight += 3;
>>+ else if ((dev->class >> 8) == PCI_CLASS_STORAGE_RAID)
>>+ *weight += 15;
>>+ else
>>+ *weight += 10;
>>+
>>+ return 0;
>>+}
>>+
>>+static unsigned int pnv_pci_ioda_pe_dma_weight(struct pnv_ioda_pe *pe)
>>+{
>>+ unsigned int weight = 0;
>>+
>>+ if ((pe->flags & PNV_IODA_PE_DEV) && pe->pdev) {
>>+ pnv_pci_ioda_dev_dma_weight(pe->pdev, &weight);
>>+ } else if ((pe->flags & PNV_IODA_PE_BUS) && pe->pbus) {
>>+ struct pci_dev *pdev;
>>+
>>+ list_for_each_entry(pdev, &pe->pbus->devices, bus_list)
>>+ pnv_pci_ioda_dev_dma_weight(pdev, &weight);
>>+ } else if ((pe->flags & PNV_IODA_PE_BUS_ALL) && pe->pbus) {
>>+ pci_walk_bus(pe->pbus, pnv_pci_ioda_dev_dma_weight, &weight);
>>+ }
>>+
>>+ return weight;
>>+}
>>+
>> static void pnv_pci_ioda1_setup_dma_pe(struct pnv_phb *phb,
>> struct pnv_ioda_pe *pe,
>> unsigned int base,
>>@@ -1858,17 +1846,12 @@ static void pnv_pci_ioda1_setup_dma_pe(struct pnv_phb *phb,
>> /* XXX FIXME: Provide 64-bit DMA facilities & non-4K TCE tables etc.. */
>> /* XXX FIXME: Allocate multi-level tables on PHB3 */
>>
>>- /* We shouldn't already have a 32-bit DMA associated */
>>- if (WARN_ON(pe->tce32_seg >= 0))
>>- return;
>>-
>> tbl = pnv_pci_table_alloc(phb->hose->node);
>> iommu_register_group(&pe->table_group, phb->hose->global_number,
>> pe->pe_number);
>> pnv_pci_link_table_and_group(phb->hose->node, 0, tbl, &pe->table_group);
>>
>> /* Grab a 32-bit TCE table */
>>- pe->tce32_seg = base;
>> pe_info(pe, " Setting up 32-bit TCE table at %08x..%08x\n",
>> base * PNV_IODA1_DMA32_SEGSIZE,
>> (base + segs) * PNV_IODA1_DMA32_SEGSIZE - 1);
>>@@ -1932,8 +1915,6 @@ static void pnv_pci_ioda1_setup_dma_pe(struct pnv_phb *phb,
>> return;
>> fail:
>> /* XXX Failure: Try to fallback to 64-bit only ? */
>>- if (pe->tce32_seg >= 0)
>>- pe->tce32_seg = -1;
>> if (tce_mem)
>> __free_pages(tce_mem, get_order(tce32_segsz * segs));
>> if (tbl) {
>>@@ -2344,10 +2325,6 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>> {
>> int64_t rc;
>>
>>- /* We shouldn't already have a 32-bit DMA associated */
>>- if (WARN_ON(pe->tce32_seg >= 0))
>>- return;
>>-
>> /* TVE #1 is selected by PCI address bit 59 */
>> pe->tce_bypass_base = 1ull << 59;
>>
>>@@ -2355,7 +2332,6 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>> pe->pe_number);
>>
>> /* The PE will reserve all possible 32-bits space */
>>- pe->tce32_seg = 0;
>> pe_info(pe, "Setting up 32-bit TCE table at 0..%08x\n",
>> phb->ioda.m32_pci_base);
>>
>>@@ -2371,11 +2347,8 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>> #endif
>>
>> rc = pnv_pci_ioda2_setup_default_config(pe);
>>- if (rc) {
>>- if (pe->tce32_seg >= 0)
>>- pe->tce32_seg = -1;
>>+ if (rc)
>> return;
>>- }
>>
>> if (pe->flags & PNV_IODA_PE_DEV)
>> iommu_add_device(&pe->pdev->dev);
>>@@ -2386,24 +2359,34 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>> static void pnv_pci_ioda1_setup_dma(struct pnv_phb *phb)
>> {
>> struct pci_controller *hose = phb->hose;
>>- unsigned int residual, remaining, segs, tw, base;
>>+ unsigned int weight, total_weight, dma_pe_count;
>>+ unsigned int residual, remaining, segs, base;
>> struct pnv_ioda_pe *pe;
>>
>>+ total_weight = 0;
>>+ dma_pe_count = 0;
>>+ list_for_each_entry(pe, &phb->ioda.pe_list, list) {
>>+ weight = pnv_pci_ioda_pe_dma_weight(pe);
>>+ if (weight > 0)
>>+ dma_pe_count++;
>>+
>>+ total_weight += weight;
>>+ }
>>+
>> /* If we have more PE# than segments available, hand out one
>> * per PE until we run out and let the rest fail. If not,
>> * then we assign at least one segment per PE, plus more based
>> * on the amount of devices under that PE
>> */
>>- if (phb->ioda.dma_pe_count > phb->ioda.tce32_count)
>>+ if (dma_pe_count > phb->ioda.tce32_count)
>> residual = 0;
>> else
>>- residual = phb->ioda.tce32_count -
>>- phb->ioda.dma_pe_count;
>>+ residual = phb->ioda.tce32_count - dma_pe_count;
>>
>> pr_info("PCI: Domain %04x has %ld available 32-bit DMA segments\n",
>> hose->global_number, phb->ioda.tce32_count);
>> pr_info("PCI: %d PE# for a total weight of %d\n",
>>- phb->ioda.dma_pe_count, phb->ioda.dma_weight);
>>+ dma_pe_count, total_weight);
>>
>> pnv_pci_ioda_setup_opal_tce_kill(phb);
>>
>>@@ -2412,24 +2395,26 @@ static void pnv_pci_ioda1_setup_dma(struct pnv_phb *phb)
>> * weight
>> */
>> remaining = phb->ioda.tce32_count;
>>- tw = phb->ioda.dma_weight;
>> base = 0;
>>- list_for_each_entry(pe, &phb->ioda.pe_dma_list, dma_link) {
>>- if (!pe->dma_weight)
>>+ list_for_each_entry(pe, &phb->ioda.pe_list, list) {
>>+ weight = pnv_pci_ioda_pe_dma_weight(pe);
>>+ if (!weight)
>> continue;
>>+
>
>
>Unrelated new line.
>

Will remove it in next revision.

Thanks,
Gavin