1 files changed, 148 insertions, 135 deletions

diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
index 7229acd9bb3a..0459e100b4e7 100644
--- a/arch/powerpc/platforms/powernv/npu-dma.c
+++ b/arch/powerpc/platforms/powernv/npu-dma.c
@@ -12,6 +12,7 @@
 #include <linux/export.h>
 #include <linux/pci.h>
 #include <linux/memblock.h>
+#include <linux/iommu.h>
 
 #include <asm/iommu.h>
 #include <asm/pnv-pci.h>
@@ -25,8 +26,6 @@
  * Other types of TCE cache invalidation are not functional in the
  * hardware.
  */
-#define TCE_KILL_INVAL_ALL PPC_BIT(0)
-
 static struct pci_dev *get_pci_dev(struct device_node *dn)
 {
 	return PCI_DN(dn)->pcidev;
@@ -138,22 +137,17 @@ static struct pnv_ioda_pe *get_gpu_pci_dev_and_pe(struct pnv_ioda_pe *npe,
 	struct pnv_ioda_pe *pe;
 	struct pci_dn *pdn;
 
-	if (npe->flags & PNV_IODA_PE_PEER) {
-		pe = npe->peers[0];
-		pdev = pe->pdev;
-	} else {
-		pdev = pnv_pci_get_gpu_dev(npe->pdev);
-		if (!pdev)
-			return NULL;
+	pdev = pnv_pci_get_gpu_dev(npe->pdev);
+	if (!pdev)
+		return NULL;
 
-		pdn = pci_get_pdn(pdev);
-		if (WARN_ON(!pdn || pdn->pe_number == IODA_INVALID_PE))
-			return NULL;
+	pdn = pci_get_pdn(pdev);
+	if (WARN_ON(!pdn || pdn->pe_number == IODA_INVALID_PE))
+		return NULL;
 
-		hose = pci_bus_to_host(pdev->bus);
-		phb = hose->private_data;
-		pe = &phb->ioda.pe_array[pdn->pe_number];
-	}
+	hose = pci_bus_to_host(pdev->bus);
+	phb = hose->private_data;
+	pe = &phb->ioda.pe_array[pdn->pe_number];
 
 	if (gpdev)
 		*gpdev = pdev;
@@ -161,92 +155,70 @@ static struct pnv_ioda_pe *get_gpu_pci_dev_and_pe(struct pnv_ioda_pe *npe,
 	return pe;
 }
 
-void pnv_npu_tce_invalidate_entire(struct pnv_ioda_pe *npe)
+long pnv_npu_set_window(struct pnv_ioda_pe *npe, int num,
+		struct iommu_table *tbl)
 {
 	struct pnv_phb *phb = npe->phb;
+	int64_t rc;
+	const unsigned long size = tbl->it_indirect_levels ?
+		tbl->it_level_size : tbl->it_size;
+	const __u64 start_addr = tbl->it_offset << tbl->it_page_shift;
+	const __u64 win_size = tbl->it_size << tbl->it_page_shift;
+
+	pe_info(npe, "Setting up window %llx..%llx pg=%lx\n",
+			start_addr, start_addr + win_size - 1,
+			IOMMU_PAGE_SIZE(tbl));
+
+	rc = opal_pci_map_pe_dma_window(phb->opal_id,
+			npe->pe_number,
+			npe->pe_number,
+			tbl->it_indirect_levels + 1,
+			__pa(tbl->it_base),
+			size << 3,
+			IOMMU_PAGE_SIZE(tbl));
+	if (rc) {
+		pe_err(npe, "Failed to configure TCE table, err %lld\n", rc);
+		return rc;
+	}
+	pnv_pci_ioda2_tce_invalidate_entire(phb, false);
 
-	if (WARN_ON(phb->type != PNV_PHB_NPU ||
-		    !phb->ioda.tce_inval_reg ||
-		    !(npe->flags & PNV_IODA_PE_DEV)))
-		return;
+	/* Add the table to the list so its TCE cache will get invalidated */
+	pnv_pci_link_table_and_group(phb->hose->node, num,
+			tbl, &npe->table_group);
 
-	mb(); /* Ensure previous TCE table stores are visible */
-	__raw_writeq(cpu_to_be64(TCE_KILL_INVAL_ALL),
-		phb->ioda.tce_inval_reg);
+	return 0;
 }
 
-void pnv_npu_tce_invalidate(struct pnv_ioda_pe *npe,
-				struct iommu_table *tbl,
-				unsigned long index,
-				unsigned long npages,
-				bool rm)
+long pnv_npu_unset_window(struct pnv_ioda_pe *npe, int num)
 {
 	struct pnv_phb *phb = npe->phb;
+	int64_t rc;
 
-	/* We can only invalidate the whole cache on NPU */
-	unsigned long val = TCE_KILL_INVAL_ALL;
-
-	if (WARN_ON(phb->type != PNV_PHB_NPU ||
-		    !phb->ioda.tce_inval_reg ||
-		    !(npe->flags & PNV_IODA_PE_DEV)))
-		return;
-
-	mb(); /* Ensure previous TCE table stores are visible */
-	if (rm)
-		__raw_rm_writeq(cpu_to_be64(val),
-		  (__be64 __iomem *) phb->ioda.tce_inval_reg_phys);
-	else
-		__raw_writeq(cpu_to_be64(val),
-			phb->ioda.tce_inval_reg);
-}
-
-void pnv_npu_init_dma_pe(struct pnv_ioda_pe *npe)
-{
-	struct pnv_ioda_pe *gpe;
-	struct pci_dev *gpdev;
-	int i, avail = -1;
-
-	if (!npe->pdev || !(npe->flags & PNV_IODA_PE_DEV))
-		return;
-
-	gpe = get_gpu_pci_dev_and_pe(npe, &gpdev);
-	if (!gpe)
-		return;
-
-	for (i = 0; i < PNV_IODA_MAX_PEER_PES; i++) {
-		/* Nothing to do if the PE is already connected. */
-		if (gpe->peers[i] == npe)
-			return;
+	pe_info(npe, "Removing DMA window\n");
 
-		if (!gpe->peers[i])
-			avail = i;
+	rc = opal_pci_map_pe_dma_window(phb->opal_id, npe->pe_number,
+			npe->pe_number,
+			0/* levels */, 0/* table address */,
+			0/* table size */, 0/* page size */);
+	if (rc) {
+		pe_err(npe, "Unmapping failed, ret = %lld\n", rc);
+		return rc;
 	}
+	pnv_pci_ioda2_tce_invalidate_entire(phb, false);
 
-	if (WARN_ON(avail < 0))
-		return;
-
-	gpe->peers[avail] = npe;
-	gpe->flags |= PNV_IODA_PE_PEER;
+	pnv_pci_unlink_table_and_group(npe->table_group.tables[num],
+			&npe->table_group);
 
-	/*
-	 * We assume that the NPU devices only have a single peer PE
-	 * (the GPU PCIe device PE).
-	 */
-	npe->peers[0] = gpe;
-	npe->flags |= PNV_IODA_PE_PEER;
+	return 0;
 }
 
 /*
- * For the NPU we want to point the TCE table at the same table as the
- * real PCI device.
+ * Enables 32 bit DMA on NPU.
  */
-static void pnv_npu_disable_bypass(struct pnv_ioda_pe *npe)
+static void pnv_npu_dma_set_32(struct pnv_ioda_pe *npe)
 {
-	struct pnv_phb *phb = npe->phb;
 	struct pci_dev *gpdev;
 	struct pnv_ioda_pe *gpe;
-	void *addr;
-	unsigned int size;
 	int64_t rc;
 
 	/*
@@ -260,14 +232,7 @@ static void pnv_npu_disable_bypass(struct pnv_ioda_pe *npe)
 	if (!gpe)
 		return;
 
-	addr = (void *)gpe->table_group.tables[0]->it_base;
-	size = gpe->table_group.tables[0]->it_size << 3;
-	rc = opal_pci_map_pe_dma_window(phb->opal_id, npe->pe_number,
-					npe->pe_number, 1, __pa(addr),
-					size, 0x1000);
-	if (rc != OPAL_SUCCESS)
-		pr_warn("%s: Error %lld setting DMA window on PHB#%d-PE#%d\n",
-			__func__, rc, phb->hose->global_number, npe->pe_number);
+	rc = pnv_npu_set_window(npe, 0, gpe->table_group.tables[0]);
 
 	/*
 	 * We don't initialise npu_pe->tce32_table as we always use
@@ -277,72 +242,120 @@ static void pnv_npu_disable_bypass(struct pnv_ioda_pe *npe)
 }
 
 /*
- * Enable/disable bypass mode on the NPU. The NPU only supports one
+ * Enables bypass mode on the NPU. The NPU only supports one
  * window per link, so bypass needs to be explicitly enabled or
  * disabled. Unlike for a PHB3 bypass and non-bypass modes can't be
  * active at the same time.
  */
-int pnv_npu_dma_set_bypass(struct pnv_ioda_pe *npe, bool enable)
+static int pnv_npu_dma_set_bypass(struct pnv_ioda_pe *npe)
 {
 	struct pnv_phb *phb = npe->phb;
 	int64_t rc = 0;
+	phys_addr_t top = memblock_end_of_DRAM();
 
 	if (phb->type != PNV_PHB_NPU || !npe->pdev)
 		return -EINVAL;
 
-	if (enable) {
-		/* Enable the bypass window */
-		phys_addr_t top = memblock_end_of_DRAM();
-
-		npe->tce_bypass_base = 0;
-		top = roundup_pow_of_two(top);
-		dev_info(&npe->pdev->dev, "Enabling bypass for PE %d\n",
-			 npe->pe_number);
-		rc = opal_pci_map_pe_dma_window_real(phb->opal_id,
-					npe->pe_number, npe->pe_number,
-					npe->tce_bypass_base, top);
-	} else {
-		/*
-		 * Disable the bypass window by replacing it with the
-		 * TCE32 window.
-		 */
-		pnv_npu_disable_bypass(npe);
-	}
+	rc = pnv_npu_unset_window(npe, 0);
+	if (rc != OPAL_SUCCESS)
+		return rc;
+
+	/* Enable the bypass window */
+
+	top = roundup_pow_of_two(top);
+	dev_info(&npe->pdev->dev, "Enabling bypass for PE %d\n",
+			npe->pe_number);
+	rc = opal_pci_map_pe_dma_window_real(phb->opal_id,
+			npe->pe_number, npe->pe_number,
+			0 /* bypass base */, top);
+
+	if (rc == OPAL_SUCCESS)
+		pnv_pci_ioda2_tce_invalidate_entire(phb, false);
 
 	return rc;
 }
 
-int pnv_npu_dma_set_mask(struct pci_dev *npdev, u64 dma_mask)
+void pnv_npu_try_dma_set_bypass(struct pci_dev *gpdev, bool bypass)
 {
-	struct pci_controller *hose = pci_bus_to_host(npdev->bus);
-	struct pnv_phb *phb = hose->private_data;
-	struct pci_dn *pdn = pci_get_pdn(npdev);
-	struct pnv_ioda_pe *npe, *gpe;
-	struct pci_dev *gpdev;
-	uint64_t top;
-	bool bypass = false;
+	int i;
+	struct pnv_phb *phb;
+	struct pci_dn *pdn;
+	struct pnv_ioda_pe *npe;
+	struct pci_dev *npdev;
 
-	if (WARN_ON(!pdn || pdn->pe_number == IODA_INVALID_PE))
-		return -ENXIO;
+	for (i = 0; ; ++i) {
+		npdev = pnv_pci_get_npu_dev(gpdev, i);
 
-	/* We only do bypass if it's enabled on the linked device */
-	npe = &phb->ioda.pe_array[pdn->pe_number];
-	gpe = get_gpu_pci_dev_and_pe(npe, &gpdev);
-	if (!gpe)
-		return -ENODEV;
+		if (!npdev)
+			break;
+
+		pdn = pci_get_pdn(npdev);
+		if (WARN_ON(!pdn || pdn->pe_number == IODA_INVALID_PE))
+			return;
+
+		phb = pci_bus_to_host(npdev->bus)->private_data;
+
+		/* We only do bypass if it's enabled on the linked device */
+		npe = &phb->ioda.pe_array[pdn->pe_number];
+
+		if (bypass) {
+			dev_info(&npdev->dev,
+					"Using 64-bit DMA iommu bypass\n");
+			pnv_npu_dma_set_bypass(npe);
+		} else {
+			dev_info(&npdev->dev, "Using 32-bit DMA via iommu\n");
+			pnv_npu_dma_set_32(npe);
+		}
+	}
+}
 
-	if (gpe->tce_bypass_enabled) {
-		top = gpe->tce_bypass_base + memblock_end_of_DRAM() - 1;
-		bypass = (dma_mask >= top);
+/* Switch ownership from platform code to external user (e.g. VFIO) */
+void pnv_npu_take_ownership(struct pnv_ioda_pe *npe)
+{
+	struct pnv_phb *phb = npe->phb;
+	int64_t rc;
+
+	/*
+	 * Note: NPU has just a single TVE in the hardware which means that
+	 * while used by the kernel, it can have either 32bit window or
+	 * DMA bypass but never both. So we deconfigure 32bit window only
+	 * if it was enabled at the moment of ownership change.
+	 */
+	if (npe->table_group.tables[0]) {
+		pnv_npu_unset_window(npe, 0);
+		return;
 	}
 
-	if (bypass)
-		dev_info(&npdev->dev, "Using 64-bit DMA iommu bypass\n");
-	else
-		dev_info(&npdev->dev, "Using 32-bit DMA via iommu\n");
+	/* Disable bypass */
+	rc = opal_pci_map_pe_dma_window_real(phb->opal_id,
+			npe->pe_number, npe->pe_number,
+			0 /* bypass base */, 0);
+	if (rc) {
+		pe_err(npe, "Failed to disable bypass, err %lld\n", rc);
+		return;
+	}
+	pnv_pci_ioda2_tce_invalidate_entire(npe->phb, false);
+}
 
-	pnv_npu_dma_set_bypass(npe, bypass);
-	*npdev->dev.dma_mask = dma_mask;
+struct pnv_ioda_pe *pnv_pci_npu_setup_iommu(struct pnv_ioda_pe *npe)
+{
+	struct pnv_phb *phb = npe->phb;
+	struct pci_bus *pbus = phb->hose->bus;
+	struct pci_dev *npdev, *gpdev = NULL, *gptmp;
+	struct pnv_ioda_pe *gpe = get_gpu_pci_dev_and_pe(npe, &gpdev);
 
-	return 0;
+	if (!gpe || !gpdev)
+		return NULL;
+
+	list_for_each_entry(npdev, &pbus->devices, bus_list) {
+		gptmp = pnv_pci_get_gpu_dev(npdev);
+
+		if (gptmp != gpdev)
+			continue;
+
+		pe_info(gpe, "Attached NPU %s\n", dev_name(&npdev->dev));
+		iommu_group_add_device(gpe->table_group.group, &npdev->dev);
+	}
+
+	return gpe;
 }