powerpc/powernv: Introduce address translation services for Nvlink2
Nvlink2 supports address translation services (ATS) allowing devices
to request address translations from an mmu known as the nest MMU
which is setup to walk the CPU page tables.
To access this functionality certain firmware calls are required to
setup and manage hardware context tables in the nvlink processing unit
(NPU). The NPU also manages forwarding of TLB invalidates (known as
address translation shootdowns/ATSDs) to attached devices.
This patch exports several methods to allow device drivers to register
a process id (PASID/PID) in the hardware tables and to receive
notification of when a device should stop issuing address translation
requests (ATRs). It also adds a fault handler to allow device drivers
to demand fault pages in.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
[mpe: Fix up comment formatting, use flush_tlb_mm()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
index e1d3e55..4eab713 100644
--- a/arch/powerpc/platforms/powernv/pci.h
+++ b/arch/powerpc/platforms/powernv/pci.h
@@ -7,6 +7,9 @@
struct pci_dn;
+/* Maximum possible number of ATSD MMIO registers per NPU */
+#define NV_NMMU_ATSD_REGS 8
+
enum pnv_phb_type {
PNV_PHB_IODA1 = 0,
PNV_PHB_IODA2 = 1,
@@ -174,6 +177,16 @@ struct pnv_phb {
struct OpalIoP7IOCErrorData hub_diag;
} diag;
+ /* Nvlink2 data */
+ struct npu {
+ int index;
+ __be64 *mmio_atsd_regs[NV_NMMU_ATSD_REGS];
+ unsigned int mmio_atsd_count;
+
+ /* Bitmask for MMIO register usage */
+ unsigned long mmio_atsd_usage;
+ } npu;
+
#ifdef CONFIG_CXL_BASE
struct cxl_afu *cxl_afu;
#endif
@@ -236,7 +249,7 @@ extern long pnv_npu_set_window(struct pnv_ioda_pe *npe, int num,
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);
-
+extern int pnv_npu2_init(struct pnv_phb *phb);
/* cxl functions */
extern bool pnv_cxl_enable_device_hook(struct pci_dev *dev);