[PATCH kernel v7 04/20] powerpc/powernv: Move npu struct from pnv_phb to pci_controller

Alexey Kardashevskiy
2018-12-20T08:23:34Z

The powernv PCI code stores NPU data in the pnv_phb struct. The latter
is referenced by pci_controller::private_data. We are going to have NPU2
support in the pseries platform as well but it does not store any
private_data in in the pci_controller struct; and even if it did,
it would be a different data structure.

This makes npu a pointer and stores it one level higher in
the pci_controller struct.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
Changes:
v5:
* removed !npu checks as this is out of scope of this patch
* added WARN_ON_ONCE in WARN_ON_ONCE(pnv_npu2_init(phb))

v4:
* changed subj from "powerpc/powernv: Detach npu struct from pnv_phb"
* got rid of global list of npus - store them now in pci_controller
* got rid of npdev_to_npu() helper
---
arch/powerpc/include/asm/pci-bridge.h | 1 +
arch/powerpc/platforms/powernv/pci.h | 16 -----
arch/powerpc/platforms/powernv/npu-dma.c | 74 +++++++++++++++++------
arch/powerpc/platforms/powernv/pci-ioda.c | 2 +-
4 files changed, 58 insertions(+), 35 deletions(-)

diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
index 94d4490..aee4fcc 100644
--- a/arch/powerpc/include/asm/pci-bridge.h
+++ b/arch/powerpc/include/asm/pci-bridge.h
@@ -129,6 +129,7 @@ struct pci_controller {
#endif /* CONFIG_PPC64 */

void *private_data;
+ struct npu *npu;
};

/* These are used for config access before all the PCI probing
diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
index 2131373..f2d50974 100644
--- a/arch/powerpc/platforms/powernv/pci.h
+++ b/arch/powerpc/platforms/powernv/pci.h
@@ -8,9 +8,6 @@

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,
@@ -176,19 +173,6 @@ struct pnv_phb {
unsigned int diag_data_size;
u8 *diag_data;

- /* 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;
-
- /* Do we need to explicitly flush the nest mmu? */
- bool nmmu_flush;
- } npu;
-
int p2p_target_count;
};

diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
index 91d488f..5e66439 100644
--- a/arch/powerpc/platforms/powernv/npu-dma.c
+++ b/arch/powerpc/platforms/powernv/npu-dma.c
@@ -327,6 +327,25 @@ struct pnv_ioda_pe *pnv_pci_npu_setup_iommu(struct pnv_ioda_pe *npe)
return gpe;
}

+/*
+ * NPU2 ATS
+ */
+/* Maximum possible number of ATSD MMIO registers per NPU */
+#define NV_NMMU_ATSD_REGS 8
+
+/* An NPU descriptor, valid for POWER9 only */
+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;
+
+ /* Do we need to explicitly flush the nest mmu? */
+ bool nmmu_flush;
+};
+
/* Maximum number of nvlinks per npu */
#define NV_MAX_LINKS 6

@@ -478,7 +497,6 @@ static void acquire_atsd_reg(struct npu_context *npu_context,
int i, j;
struct npu *npu;
struct pci_dev *npdev;
- struct pnv_phb *nphb;

for (i = 0; i <= max_npu2_index; i++) {
mmio_atsd_reg[i].reg = -1;
@@ -493,8 +511,7 @@ static void acquire_atsd_reg(struct npu_context *npu_context,
if (!npdev)
continue;

- nphb = pci_bus_to_host(npdev->bus)->private_data;
- npu = &nphb->npu;
+ npu = pci_bus_to_host(npdev->bus)->npu;
mmio_atsd_reg[i].npu = npu;
mmio_atsd_reg[i].reg = get_mmio_atsd_reg(npu);
while (mmio_atsd_reg[i].reg < 0) {
@@ -662,6 +679,7 @@ struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
struct pnv_phb *nphb;
struct npu *npu;
struct npu_context *npu_context;
+ struct pci_controller *hose;

/*
* At present we don't support GPUs connected to multiple NPUs and I'm
@@ -689,8 +707,9 @@ struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
return ERR_PTR(-EINVAL);
}

- nphb = pci_bus_to_host(npdev->bus)->private_data;
- npu = &nphb->npu;
+ hose = pci_bus_to_host(npdev->bus);
+ nphb = hose->private_data;
+ npu = hose->npu;

/*
* Setup the NPU context table for a particular GPU. These need to be
@@ -764,7 +783,7 @@ struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
*/
WRITE_ONCE(npu_context->npdev[npu->index][nvlink_index], npdev);

- if (!nphb->npu.nmmu_flush) {
+ if (!npu->nmmu_flush) {
/*
* If we're not explicitly flushing ourselves we need to mark
* the thread for global flushes
@@ -802,6 +821,7 @@ void pnv_npu2_destroy_context(struct npu_context *npu_context,
struct pci_dev *npdev = pnv_pci_get_npu_dev(gpdev, 0);
struct device_node *nvlink_dn;
u32 nvlink_index;
+ struct pci_controller *hose;

if (WARN_ON(!npdev))
return;
@@ -809,8 +829,9 @@ void pnv_npu2_destroy_context(struct npu_context *npu_context,
if (!firmware_has_feature(FW_FEATURE_OPAL))
return;

- nphb = pci_bus_to_host(npdev->bus)->private_data;
- npu = &nphb->npu;
+ hose = pci_bus_to_host(npdev->bus);
+ nphb = hose->private_data;
+ npu = hose->npu;
nvlink_dn = of_parse_phandle(npdev->dev.of_node, "ibm,nvlink", 0);
if (WARN_ON(of_property_read_u32(nvlink_dn, "ibm,npu-link-index",
&nvlink_index)))
@@ -888,9 +909,15 @@ int pnv_npu2_init(struct pnv_phb *phb)
struct pci_dev *gpdev;
static int npu_index;
uint64_t rc = 0;
+ struct pci_controller *hose = phb->hose;
+ struct npu *npu;
+ int ret;

- phb->npu.nmmu_flush =
- of_property_read_bool(phb->hose->dn, "ibm,nmmu-flush");
+ npu = kzalloc(sizeof(*npu), GFP_KERNEL);
+ if (!npu)
+ return -ENOMEM;
+
+ npu->nmmu_flush = of_property_read_bool(hose->dn, "ibm,nmmu-flush");
for_each_child_of_node(phb->hose->dn, dn) {
gpdev = pnv_pci_get_gpu_dev(get_pci_dev(dn));
if (gpdev) {
@@ -904,18 +931,29 @@ int pnv_npu2_init(struct pnv_phb *phb)
}
}

- for (i = 0; !of_property_read_u64_index(phb->hose->dn, "ibm,mmio-atsd",
+ for (i = 0; !of_property_read_u64_index(hose->dn, "ibm,mmio-atsd",
i, &mmio_atsd); i++)
- phb->npu.mmio_atsd_regs[i] = ioremap(mmio_atsd, 32);
+ npu->mmio_atsd_regs[i] = ioremap(mmio_atsd, 32);

- pr_info("NPU%lld: Found %d MMIO ATSD registers", phb->opal_id, i);
- phb->npu.mmio_atsd_count = i;
- phb->npu.mmio_atsd_usage = 0;
+ pr_info("NPU%d: Found %d MMIO ATSD registers", hose->global_number, i);
+ npu->mmio_atsd_count = i;
+ npu->mmio_atsd_usage = 0;
npu_index++;
- if (WARN_ON(npu_index >= NV_MAX_NPUS))
- return -ENOSPC;
+ if (WARN_ON(npu_index >= NV_MAX_NPUS)) {
+ ret = -ENOSPC;
+ goto fail_exit;
+ }
max_npu2_index = npu_index;
- phb->npu.index = npu_index;
+ npu->index = npu_index;
+ hose->npu = npu;

return 0;
+
+fail_exit:
+ for (i = 0; i < npu->mmio_atsd_count; ++i)
+ iounmap(npu->mmio_atsd_regs[i]);
+
+ kfree(npu);
+
+ return ret;
}
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 29c6837..8528fb9 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1283,7 +1283,7 @@ static void pnv_pci_ioda_setup_PEs(void)
pnv_ioda_reserve_pe(phb, 0);
pnv_ioda_setup_npu_PEs(hose->bus);
if (phb->model == PNV_PHB_MODEL_NPU2)
- pnv_npu2_init(phb);
+ WARN_ON_ONCE(pnv_npu2_init(phb));
}
if (phb->type == PNV_PHB_NPU_OCAPI) {
bus = hose->bus;
--
2.17.1