[PATCH v7 17/50] powerpc/powernv: Avoid calculating DMA32 segments on PHB3

Gavin Shan gwshan at linux.vnet.ibm.com
Thu Nov 5 00:12:17 AEDT 2015


In pnv_ioda_setup_dma(), it's unnecessary to calculate the DMA32
segments for PEs on PHB3 as the whole available DMA32 space can
be assigned to one specific PE on PHB3.

This splits pnv_ioda_setup_dma() to pnv_pci_ioda1_setup_dma() and
pnv_pci_ioda2_setup_dma() in order to avoid calculating DMA32
segments for PEs on PHB3. No logical changes introduced.

Signed-off-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/pci-ioda.c | 41 ++++++++++++++++++-------------
 1 file changed, 24 insertions(+), 17 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 5a08e20..4c2e023 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -2383,7 +2383,7 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
 		pnv_ioda_setup_bus_dma(pe, pe->pbus);
 }
 
-static void pnv_ioda_setup_dma(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;
@@ -2428,26 +2428,30 @@ static void pnv_ioda_setup_dma(struct pnv_phb *phb)
 				segs = remaining;
 		}
 
-		/*
-		 * For IODA2 compliant PHB3, we needn't care about the weight.
-		 * The all available 32-bits DMA space will be assigned to
-		 * the specific PE.
-		 */
-		if (phb->type == PNV_PHB_IODA1) {
-			pe_info(pe, "DMA weight %d, assigned %d DMA32 segments\n",
-				pe->dma_weight, segs);
-			pnv_pci_ioda1_setup_dma_pe(phb, pe, base, segs);
-		} else {
-			pe_info(pe, "Assign DMA32 space\n");
-			segs = 0;
-			pnv_pci_ioda2_setup_dma_pe(phb, pe);
-		}
+		pe_info(pe, "DMA weight %d, assigned %d DMA32 segments\n",
+			pe->dma_weight, segs);
+		pnv_pci_ioda1_setup_dma_pe(phb, pe, base, segs);
 
 		remaining -= segs;
 		base += segs;
 	}
 }
 
+static void pnv_pci_ioda2_setup_dma(struct pnv_phb *phb)
+{
+	struct pnv_ioda_pe *pe;
+
+	pnv_pci_ioda_setup_opal_tce_kill(phb);
+
+	list_for_each_entry(pe, &phb->ioda.pe_dma_list, dma_link) {
+		if (!pe->dma_weight)
+			continue;
+
+		pe_info(pe, "Assign DMA32 space\n");
+		pnv_pci_ioda2_setup_dma_pe(phb, pe);
+	}
+}
+
 #ifdef CONFIG_PCI_MSI
 static void pnv_ioda2_msi_eoi(struct irq_data *d)
 {
@@ -2931,10 +2935,13 @@ static void pnv_pci_ioda_setup_DMA(void)
 	struct pnv_phb *phb;
 
 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
-		pnv_ioda_setup_dma(hose->private_data);
+		phb = hose->private_data;
+		if (phb->type == PNV_PHB_IODA1)
+			pnv_pci_ioda1_setup_dma(phb);
+		else
+			pnv_pci_ioda2_setup_dma(phb);
 
 		/* Mark the PHB initialization done */
-		phb = hose->private_data;
 		phb->initialized = 1;
 	}
 }
-- 
2.1.0



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