[PATCH kernel 5/5] powerpc/powernv/npu: Add helper to map GPU to LPAR

[Alexey Kardashevskiy <aik@xxxxxxxxx>]

In order to make ATS work and translate addresses for arbitrary
LPID and PID, we need to program an NPU with these.

This implements a helper to assign a GPU to LPAR and program the NPU
with a wildcard for PID. The helper also takes MSR (only DR/HV/PR/SF bits
are allowed) to program them into NPU2 for ATS checkout requests.

Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx>
---
 arch/powerpc/include/asm/pci.h           |  2 ++
 arch/powerpc/platforms/powernv/npu-dma.c | 38 ++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+)

diff --git a/arch/powerpc/include/asm/pci.h b/arch/powerpc/include/asm/pci.h
index f196df6..c3c9728 100644
--- a/arch/powerpc/include/asm/pci.h
+++ b/arch/powerpc/include/asm/pci.h
@@ -131,5 +131,7 @@ extern struct pci_dev *pnv_pci_get_gpu_dev(struct pci_dev *npdev);
 extern struct pci_dev *pnv_pci_get_npu_dev(struct pci_dev *gpdev, int index);
 extern void pnv_npu2_devices_init(void);
 extern int pnv_npu2_init(struct pci_controller *hose);
+extern int pnv_npu2_map_lpar_dev(struct pci_controller *hose,
+		struct pci_dev *gpdev, unsigned int lparid, unsigned long msr);
 
 #endif /* __ASM_POWERPC_PCI_H */
diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
index 677f30a..1dde753 100644
--- a/arch/powerpc/platforms/powernv/npu-dma.c
+++ b/arch/powerpc/platforms/powernv/npu-dma.c
@@ -1047,3 +1047,41 @@ void pnv_npu2_map_lpar_phb(struct pnv_phb *nphb, unsigned long msr)
 		dev_err(&gpdev->dev, "Failed to init context: %d\n", ret);
 	}
 }
+
+int pnv_npu2_map_lpar_dev(struct pci_controller *hose, struct pci_dev *gpdev,
+		unsigned int lparid, unsigned long msr)
+{
+	int ret;
+	struct pnv_phb *nphb = hose->private_data;
+
+	dev_dbg(&gpdev->dev, "Map LPAR opalid=%llu lparid=%u\n",
+			nphb->opal_id, lparid);
+	/*
+	 * Currently we only support radix and non-zero LPCR only makes sense
+	 * for hash tables so skiboot expects the LPCR parameter to be a zero.
+	 */
+	ret = opal_npu_map_lpar(nphb->opal_id,
+			PCI_DEVID(gpdev->bus->number, gpdev->devfn), lparid,
+			0 /* LPCR bits */);
+	if (ret) {
+		dev_err(&gpdev->dev, "Error %d mapping device to LPAR\n", ret);
+		return ret;
+	}
+
+	dev_dbg(&gpdev->dev, "destroy context opalid=%llu msr=%lx\n",
+			nphb->opal_id, msr);
+	ret = opal_npu_destroy_context(nphb->opal_id, 0/*__unused*/,
+			PCI_DEVID(gpdev->bus->number, gpdev->devfn));
+	if (ret)
+		dev_err(&gpdev->dev, "Failed to destroy context: %d\n", ret);
+
+	dev_dbg(&gpdev->dev, "init context opalid=%llu msr=%lx\n",
+			nphb->opal_id, msr);
+	ret = opal_npu_init_context(nphb->opal_id, 0/*__unused*/, msr,
+			PCI_DEVID(gpdev->bus->number, gpdev->devfn));
+	if (ret)
+		dev_err(&gpdev->dev, "Failed to init context: %d\n", ret);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(pnv_npu2_map_lpar_dev);
-- 
2.11.0