| Message ID | 20220126195043.28376-2-prabhakar.mahadev-lad.rj@bp.renesas.com (mailing list archive) |
|---|---|
| State | RFC |
| Delegated to: | Lorenzo Pieralisi |
| Headers | show |
| Series | PCIe EPF support for internal DMAC handling and driver update for R-Car PCIe EP to support DMAC | expand |
On Wed, Jan 26, 2022 at 07:50:39PM +0000, Lad Prabhakar wrote: > Add flag to indicate if PCIe EP supports internal DMAC and also add a > wrapper function which invokes dmac_transfer() callback which lands > in the PCIe EP driver. > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> > --- > drivers/pci/endpoint/pci-epf-core.c | 32 +++++++++++++++++++++++++++++ > include/linux/pci-epc.h | 8 ++++++++ > include/linux/pci-epf.h | 7 +++++++ > 3 files changed, 47 insertions(+) > > diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c > index 9ed556936f48..f70576d0d4b2 100644 > --- a/drivers/pci/endpoint/pci-epf-core.c > +++ b/drivers/pci/endpoint/pci-epf-core.c > @@ -239,6 +239,38 @@ void pci_epf_remove_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf) > } > EXPORT_SYMBOL_GPL(pci_epf_remove_vepf); > > +/** > + * pci_epf_internal_dmac_xfr() - transfer data between EPC and remote PCIe RC Transfer data between EP and host using internal DMA engine > + * @epf: the EPF device that performs the data transfer operation > + * @dma_dst: The destination address of the data transfer. It can be a physical > + * address given by pci_epc_mem_alloc_addr or DMA mapping APIs. > + * @dma_src: The source address of the data transfer. It can be a physical > + * address given by pci_epc_mem_alloc_addr or DMA mapping APIs. > + * @len: The size of the data transfer > + * > + * Invoke to transfer data between EPC and remote PCIe RC using internal dmac. > + */ > +int pci_epf_internal_dmac_xfr(struct pci_epf *epf, dma_addr_t dma_dst, > + dma_addr_t dma_src, size_t len, > + enum pci_epf_xfr_direction dir) How about "pci_epf_internal_dma_xfer"? I think DMAC is somewhat platform specific so we could just use DMA. And "xfer" is being used more commonly for "transfer". > +{ > + struct pci_epc *epc = epf->epc; > + int ret; > + > + if (IS_ERR_OR_NULL(epc) || IS_ERR_OR_NULL(epf)) > + return -EINVAL; > + > + if (!epc->ops->dmac_transfer) > + return -EINVAL; > + > + mutex_lock(&epf->lock); > + ret = epc->ops->dmac_transfer(epc, epf, dma_dst, dma_src, len, dir); internal_dma_xfer? It doesn't look perfect but I can't think of any other way to represent it as an internal dma callback. > + mutex_unlock(&epf->lock); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(pci_epf_internal_dmac_xfr); > + > /** > * pci_epf_free_space() - free the allocated PCI EPF register space > * @epf: the EPF device from whom to free the memory > diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h > index a48778e1a4ee..b55dacd09e1e 100644 > --- a/include/linux/pci-epc.h > +++ b/include/linux/pci-epc.h > @@ -58,6 +58,7 @@ pci_epc_interface_string(enum pci_epc_interface_type type) > * @map_msi_irq: ops to map physical address to MSI address and return MSI data > * @start: ops to start the PCI link > * @stop: ops to stop the PCI link > + * @dmac_transfer: ops to transfer data using internal DMAC > * @get_features: ops to get the features supported by the EPC > * @owner: the module owner containing the ops > */ > @@ -86,6 +87,9 @@ struct pci_epc_ops { > u32 *msi_addr_offset); > int (*start)(struct pci_epc *epc); > void (*stop)(struct pci_epc *epc); > + int (*dmac_transfer)(struct pci_epc *epc, struct pci_epf *epf, > + dma_addr_t dma_dst, dma_addr_t dma_src, > + size_t len, enum pci_epf_xfr_direction dir); > const struct pci_epc_features* (*get_features)(struct pci_epc *epc, > u8 func_no, u8 vfunc_no); > struct module *owner; > @@ -159,6 +163,8 @@ struct pci_epc { > * for initialization > * @msi_capable: indicate if the endpoint function has MSI capability > * @msix_capable: indicate if the endpoint function has MSI-X capability > + * @internal_dmac: indicate if the endpoint function has internal DMAC > + * @internal_dmac_mask: indicates the DMA mask to be applied for the device > * @reserved_bar: bitmap to indicate reserved BAR unavailable to function driver > * @bar_fixed_64bit: bitmap to indicate fixed 64bit BARs > * @bar_fixed_size: Array specifying the size supported by each BAR > @@ -169,6 +175,8 @@ struct pci_epc_features { > unsigned int core_init_notifier : 1; > unsigned int msi_capable : 1; > unsigned int msix_capable : 1; > + unsigned int internal_dmac : 1; > + u64 internal_dmac_mask; internal_dma? > u8 reserved_bar; > u8 bar_fixed_64bit; > u64 bar_fixed_size[PCI_STD_NUM_BARS]; > diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h > index 009a07147c61..78d661db085d 100644 > --- a/include/linux/pci-epf.h > +++ b/include/linux/pci-epf.h > @@ -32,6 +32,11 @@ enum pci_barno { > BAR_5, > }; > > +enum pci_epf_xfr_direction { > + PCIE_TO_INTERNAL, > + INTERNAL_TO_PCIE, I think we could just use "dma_data_direction" as we are anyway transferring data between host and device. Thanks, Mani > +}; > + > /** > * struct pci_epf_header - represents standard configuration header > * @vendorid: identifies device manufacturer > @@ -209,6 +214,8 @@ void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar, > enum pci_epc_interface_type type); > int pci_epf_bind(struct pci_epf *epf); > void pci_epf_unbind(struct pci_epf *epf); > +int pci_epf_internal_dmac_xfr(struct pci_epf *epf, dma_addr_t dma_dst, dma_addr_t dma_src, > + size_t len, enum pci_epf_xfr_direction dir); > struct config_group *pci_epf_type_add_cfs(struct pci_epf *epf, > struct config_group *group); > int pci_epf_add_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf); > -- > 2.25.1 >
diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c index 9ed556936f48..f70576d0d4b2 100644 --- a/drivers/pci/endpoint/pci-epf-core.c +++ b/drivers/pci/endpoint/pci-epf-core.c @@ -239,6 +239,38 @@ void pci_epf_remove_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf) } EXPORT_SYMBOL_GPL(pci_epf_remove_vepf); +/** + * pci_epf_internal_dmac_xfr() - transfer data between EPC and remote PCIe RC + * @epf: the EPF device that performs the data transfer operation + * @dma_dst: The destination address of the data transfer. It can be a physical + * address given by pci_epc_mem_alloc_addr or DMA mapping APIs. + * @dma_src: The source address of the data transfer. It can be a physical + * address given by pci_epc_mem_alloc_addr or DMA mapping APIs. + * @len: The size of the data transfer + * + * Invoke to transfer data between EPC and remote PCIe RC using internal dmac. + */ +int pci_epf_internal_dmac_xfr(struct pci_epf *epf, dma_addr_t dma_dst, + dma_addr_t dma_src, size_t len, + enum pci_epf_xfr_direction dir) +{ + struct pci_epc *epc = epf->epc; + int ret; + + if (IS_ERR_OR_NULL(epc) || IS_ERR_OR_NULL(epf)) + return -EINVAL; + + if (!epc->ops->dmac_transfer) + return -EINVAL; + + mutex_lock(&epf->lock); + ret = epc->ops->dmac_transfer(epc, epf, dma_dst, dma_src, len, dir); + mutex_unlock(&epf->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epf_internal_dmac_xfr); + /** * pci_epf_free_space() - free the allocated PCI EPF register space * @epf: the EPF device from whom to free the memory diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index a48778e1a4ee..b55dacd09e1e 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -58,6 +58,7 @@ pci_epc_interface_string(enum pci_epc_interface_type type) * @map_msi_irq: ops to map physical address to MSI address and return MSI data * @start: ops to start the PCI link * @stop: ops to stop the PCI link + * @dmac_transfer: ops to transfer data using internal DMAC * @get_features: ops to get the features supported by the EPC * @owner: the module owner containing the ops */ @@ -86,6 +87,9 @@ struct pci_epc_ops { u32 *msi_addr_offset); int (*start)(struct pci_epc *epc); void (*stop)(struct pci_epc *epc); + int (*dmac_transfer)(struct pci_epc *epc, struct pci_epf *epf, + dma_addr_t dma_dst, dma_addr_t dma_src, + size_t len, enum pci_epf_xfr_direction dir); const struct pci_epc_features* (*get_features)(struct pci_epc *epc, u8 func_no, u8 vfunc_no); struct module *owner; @@ -159,6 +163,8 @@ struct pci_epc { * for initialization * @msi_capable: indicate if the endpoint function has MSI capability * @msix_capable: indicate if the endpoint function has MSI-X capability + * @internal_dmac: indicate if the endpoint function has internal DMAC + * @internal_dmac_mask: indicates the DMA mask to be applied for the device * @reserved_bar: bitmap to indicate reserved BAR unavailable to function driver * @bar_fixed_64bit: bitmap to indicate fixed 64bit BARs * @bar_fixed_size: Array specifying the size supported by each BAR @@ -169,6 +175,8 @@ struct pci_epc_features { unsigned int core_init_notifier : 1; unsigned int msi_capable : 1; unsigned int msix_capable : 1; + unsigned int internal_dmac : 1; + u64 internal_dmac_mask; u8 reserved_bar; u8 bar_fixed_64bit; u64 bar_fixed_size[PCI_STD_NUM_BARS]; diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h index 009a07147c61..78d661db085d 100644 --- a/include/linux/pci-epf.h +++ b/include/linux/pci-epf.h @@ -32,6 +32,11 @@ enum pci_barno { BAR_5, }; +enum pci_epf_xfr_direction { + PCIE_TO_INTERNAL, + INTERNAL_TO_PCIE, +}; + /** * struct pci_epf_header - represents standard configuration header * @vendorid: identifies device manufacturer @@ -209,6 +214,8 @@ void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar, enum pci_epc_interface_type type); int pci_epf_bind(struct pci_epf *epf); void pci_epf_unbind(struct pci_epf *epf); +int pci_epf_internal_dmac_xfr(struct pci_epf *epf, dma_addr_t dma_dst, dma_addr_t dma_src, + size_t len, enum pci_epf_xfr_direction dir); struct config_group *pci_epf_type_add_cfs(struct pci_epf *epf, struct config_group *group); int pci_epf_add_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf);
Add flag to indicate if PCIe EP supports internal DMAC and also add a wrapper function which invokes dmac_transfer() callback which lands in the PCIe EP driver. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> --- drivers/pci/endpoint/pci-epf-core.c | 32 +++++++++++++++++++++++++++++ include/linux/pci-epc.h | 8 ++++++++ include/linux/pci-epf.h | 7 +++++++ 3 files changed, 47 insertions(+)