[PATCH kernel v4 14/19] powerpc/powernv/npu: Convert NPU IOMMU helpers to iommu_table_group_ops

[Alexey Kardashevskiy <aik@ozlabs.ru>]

At the moment NPU IOMMU is manipulated directly from the IODA2 PCI
PE code; PCI PE acts as a master to NPU PE. Soon we will have compound
IOMMU groups with several PEs from several different PHB (such as
interconnected GPUs and NPUs) so there will be no single master but
a one big IOMMU group.

This makes a first step and converts an NPU PE with a set of extern
function to a table group.

This should cause no behavioral change. Note that
pnv_npu_release_ownership() has never been implemented.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
---
 arch/powerpc/platforms/powernv/pci.h      |  5 ----
 arch/powerpc/platforms/powernv/npu-dma.c  | 34 ++++++++++++++++++-----
 arch/powerpc/platforms/powernv/pci-ioda.c | 10 +++++--
 3 files changed, 34 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
index ddb4f02..cf9f748 100644
--- a/arch/powerpc/platforms/powernv/pci.h
+++ b/arch/powerpc/platforms/powernv/pci.h
@@ -216,11 +216,6 @@ extern void pe_level_printk(const struct pnv_ioda_pe *pe, const char *level,
 extern void pnv_npu_try_dma_set_bypass(struct pci_dev *gpdev, bool bypass);
 extern void pnv_pci_ioda2_tce_invalidate_entire(struct pnv_phb *phb, bool rm);
 extern struct pnv_ioda_pe *pnv_pci_npu_setup_iommu(struct pnv_ioda_pe *npe);
-extern long pnv_npu_set_window(struct pnv_ioda_pe *npe, int num,
-		struct iommu_table *tbl);
-extern long pnv_npu_unset_window(struct pnv_ioda_pe *npe, int num);
-extern void pnv_npu_take_ownership(struct pnv_ioda_pe *npe);
-extern void pnv_npu_release_ownership(struct pnv_ioda_pe *npe);
 
 /* pci-ioda-tce.c */
 #define POWERNV_IOMMU_DEFAULT_LEVELS	1
diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
index 26063fb..dc629ee 100644
--- a/arch/powerpc/platforms/powernv/npu-dma.c
+++ b/arch/powerpc/platforms/powernv/npu-dma.c
@@ -121,9 +121,14 @@ static struct pnv_ioda_pe *get_gpu_pci_dev_and_pe(struct pnv_ioda_pe *npe,
 	return pe;
 }
 
-long pnv_npu_set_window(struct pnv_ioda_pe *npe, int num,
+static long pnv_npu_unset_window(struct iommu_table_group *table_group,
+		int num);
+
+static long pnv_npu_set_window(struct iommu_table_group *table_group, int num,
 		struct iommu_table *tbl)
 {
+	struct pnv_ioda_pe *npe = container_of(table_group, struct pnv_ioda_pe,
+			table_group);
 	struct pnv_phb *phb = npe->phb;
 	int64_t rc;
 	const unsigned long size = tbl->it_indirect_levels ?
@@ -134,7 +139,7 @@ long pnv_npu_set_window(struct pnv_ioda_pe *npe, int num,
 
 	/* NPU has just one TVE so if there is another table, remove it first */
 	if (npe->table_group.tables[num2])
-		pnv_npu_unset_window(npe, num2);
+		pnv_npu_unset_window(&npe->table_group, num2);
 
 	pe_info(npe, "Setting up window %llx..%llx pg=%lx\n",
 			start_addr, start_addr + win_size - 1,
@@ -160,8 +165,10 @@ long pnv_npu_set_window(struct pnv_ioda_pe *npe, int num,
 	return 0;
 }
 
-long pnv_npu_unset_window(struct pnv_ioda_pe *npe, int num)
+static long pnv_npu_unset_window(struct iommu_table_group *table_group, int num)
 {
+	struct pnv_ioda_pe *npe = container_of(table_group, struct pnv_ioda_pe,
+			table_group);
 	struct pnv_phb *phb = npe->phb;
 	int64_t rc;
 
@@ -206,7 +213,8 @@ static void pnv_npu_dma_set_32(struct pnv_ioda_pe *npe)
 	if (!gpe)
 		return;
 
-	rc = pnv_npu_set_window(npe, 0, gpe->table_group.tables[0]);
+	rc = pnv_npu_set_window(&npe->table_group, 0,
+			gpe->table_group.tables[0]);
 
 	/*
 	 * NVLink devices use the same TCE table configuration as
@@ -231,7 +239,7 @@ static int pnv_npu_dma_set_bypass(struct pnv_ioda_pe *npe)
 	if (phb->type != PNV_PHB_NPU_NVLINK || !npe->pdev)
 		return -EINVAL;
 
-	rc = pnv_npu_unset_window(npe, 0);
+	rc = pnv_npu_unset_window(&npe->table_group, 0);
 	if (rc != OPAL_SUCCESS)
 		return rc;
 
@@ -284,9 +292,12 @@ void pnv_npu_try_dma_set_bypass(struct pci_dev *gpdev, bool bypass)
 	}
 }
 
+#ifdef CONFIG_IOMMU_API
 /* Switch ownership from platform code to external user (e.g. VFIO) */
-void pnv_npu_take_ownership(struct pnv_ioda_pe *npe)
+static void pnv_npu_take_ownership(struct iommu_table_group *table_group)
 {
+	struct pnv_ioda_pe *npe = container_of(table_group, struct pnv_ioda_pe,
+			table_group);
 	struct pnv_phb *phb = npe->phb;
 	int64_t rc;
 
@@ -297,7 +308,7 @@ void pnv_npu_take_ownership(struct pnv_ioda_pe *npe)
 	 * if it was enabled at the moment of ownership change.
 	 */
 	if (npe->table_group.tables[0]) {
-		pnv_npu_unset_window(npe, 0);
+		pnv_npu_unset_window(&npe->table_group, 0);
 		return;
 	}
 
@@ -312,6 +323,12 @@ void pnv_npu_take_ownership(struct pnv_ioda_pe *npe)
 	pnv_pci_ioda2_tce_invalidate_entire(npe->phb, false);
 }
 
+static struct iommu_table_group_ops pnv_pci_npu_ops = {
+	.set_window = pnv_npu_set_window,
+	.unset_window = pnv_npu_unset_window,
+	.take_ownership = pnv_npu_take_ownership,
+};
+
 struct pnv_ioda_pe *pnv_pci_npu_setup_iommu(struct pnv_ioda_pe *npe)
 {
 	struct pnv_phb *phb = npe->phb;
@@ -322,6 +339,8 @@ struct pnv_ioda_pe *pnv_pci_npu_setup_iommu(struct pnv_ioda_pe *npe)
 	if (!gpe || !gpdev)
 		return NULL;
 
+	npe->table_group.ops = &pnv_pci_npu_ops;
+
 	list_for_each_entry(npdev, &pbus->devices, bus_list) {
 		gptmp = pnv_pci_get_gpu_dev(npdev);
 
@@ -334,6 +353,7 @@ struct pnv_ioda_pe *pnv_pci_npu_setup_iommu(struct pnv_ioda_pe *npe)
 
 	return gpe;
 }
+#endif /* !CONFIG_IOMMU_API */
 
 /*
  * NPU2 ATS
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 07f0751..c9e7bcb 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -2669,12 +2669,13 @@ static struct pnv_ioda_pe *gpe_table_group_to_npe(
 static long pnv_pci_ioda2_npu_set_window(struct iommu_table_group *table_group,
 		int num, struct iommu_table *tbl)
 {
+	struct pnv_ioda_pe *npe = gpe_table_group_to_npe(table_group);
 	long ret = pnv_pci_ioda2_set_window(table_group, num, tbl);
 
 	if (ret)
 		return ret;
 
-	ret = pnv_npu_set_window(gpe_table_group_to_npe(table_group), num, tbl);
+	ret = npe->table_group.ops->set_window(&npe->table_group, num, tbl);
 	if (ret)
 		pnv_pci_ioda2_unset_window(table_group, num);
 
@@ -2685,17 +2686,20 @@ static long pnv_pci_ioda2_npu_unset_window(
 		struct iommu_table_group *table_group,
 		int num)
 {
+	struct pnv_ioda_pe *npe = gpe_table_group_to_npe(table_group);
 	long ret = pnv_pci_ioda2_unset_window(table_group, num);
 
 	if (ret)
 		return ret;
 
-	return pnv_npu_unset_window(gpe_table_group_to_npe(table_group), num);
+	return npe->table_group.ops->unset_window(&npe->table_group, num);
 }
 
 static void pnv_ioda2_npu_take_ownership(struct iommu_table_group *table_group)
 {
-	pnv_npu_take_ownership(gpe_table_group_to_npe(table_group));
+	struct pnv_ioda_pe *npe = gpe_table_group_to_npe(table_group);
+
+	npe->table_group.ops->take_ownership(&npe->table_group);
 	pnv_ioda2_take_ownership(table_group);
 }
 
-- 
2.17.1