| Message ID | 20241012113246.95634-1-dlemoal@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | Improve PCI memory mapping API | expand |
On Sat, Oct 12, 2024 at 08:32:40PM +0900, Damien Le Moal wrote: > This series introduces the new functions pci_epc_mem_map() and > pci_epc_mem_unmap() to improve handling of the PCI address mapping > alignment constraints of endpoint controllers in a controller > independent manner. > > The issue fixed is that the fixed alignment defined by the "align" field > of struct pci_epc_features is defined for inbound ATU entries (e.g. > BARs) and is a fixed value, whereas some controllers need a PCI address > alignment that depends on the PCI address itself. For instance, the > rk3399 SoC controller in endpoint mode uses the lower bits of the local > endpoint memory address as the lower bits for the PCI addresses for data > transfers. That is, when mapping local memory, one must take into > account the number of bits of the RC PCI address that change from the > start address of the mapping. > > To fix this, the new endpoint controller method .align_addr is > introduced and called from the new pci_epc_mem_map() function. This > method is optional and for controllers that do not define it, it is > assumed that the controller has no PCI address constraint. > > The functions pci_epc_mem_map() is a helper function which obtains > the mapping information, allocates endpoint controller memory according > to the mapping size obtained and maps the memory. pci_epc_mem_unmap() > unmaps and frees the endpoint memory. > > This series is organized as follows: > - Patch 1 introduces a small helper to clean up the epc core code > - Patch 2 improves pci_epc_mem_alloc_addr() > - Patch 3 introduce the new align_addr() endpoint controller method > and the epc functions pci_epc_mem_map() and pci_epc_mem_unmap(). > - Patch 4 documents these new functions. > - Patch 5 modifies the test endpoint function driver to use > pci_epc_mem_map() and pci_epc_mem_unmap() to illustrate the use of > these functions. > - Finally, patch 6 implements the RK3588 endpoint controller driver > .align_addr() operation to satisfy that controller PCI address > alignment constraint. > > This patch series was tested using the pci endpoint test driver (as-is > and a modified version removing memory allocation alignment on the host > side) as well as with a prototype NVMe endpoint function driver (where > data transfers use addresses that are never aligned to any specific > boundary). > Applied to pci/endpoint! - Mani > Changes from v5: > - Changed patch 3 to rename the new controller operation to align_addr > and change its interface. Patch 6 is changed accordingly. > > Changes from v4: > - Removed the patch adding the pci_epc_map_align() function. The former > .map_align controller operation is now introduced in patch 3 as > "get_mem_map()" and used directly in the new pci_epf_mem_map() > function. > - Modified the documentation patch 4 to reflect the previous change. > - Changed patch 6 title and modified it to rename map_align to > get_mem_map in accordance with the new patch 3. > - Added review tags > > Changes from v3: > - Addressed Niklas comments (improved patch 2 commit message, added > comments in the pci_epc_map_align() function in patch 3, typos and > improvements in patch 5, patch 7 commit message). > - Added review tags > > Changes from v2: > - Dropped all patches for the rockchip-ep. These patches will be sent > later as a separate series. > - Added patch 2 and 5 > - Added review tags to patch 1 > > Changes from v1: > - Changed pci_epc_check_func() to pci_epc_function_is_valid() in patch > 1. > - Removed patch "PCI: endpoint: Improve pci_epc_mem_alloc_addr()" > (former patch 2 of v1) > - Various typos cleanups all over. Also fixed some blank space > indentation. > - Added review tags > > Damien Le Moal (6): > PCI: endpoint: Introduce pci_epc_function_is_valid() > PCI: endpoint: Improve pci_epc_mem_alloc_addr() > PCI: endpoint: Introduce pci_epc_mem_map()/unmap() > PCI: endpoint: Update documentation > PCI: endpoint: test: Use pci_epc_mem_map/unmap() > PCI: dwc: endpoint: Implement the pci_epc_ops::align_addr() operation > > Documentation/PCI/endpoint/pci-endpoint.rst | 29 ++ > .../pci/controller/dwc/pcie-designware-ep.c | 15 + > drivers/pci/endpoint/functions/pci-epf-test.c | 372 +++++++++--------- > drivers/pci/endpoint/pci-epc-core.c | 182 ++++++--- > drivers/pci/endpoint/pci-epc-mem.c | 9 +- > include/linux/pci-epc.h | 38 ++ > 6 files changed, 415 insertions(+), 230 deletions(-) > > -- > 2.47.0 >
On 10/12/24 20:57, Manivannan Sadhasivam wrote: > On Sat, Oct 12, 2024 at 08:32:40PM +0900, Damien Le Moal wrote: >> This series introduces the new functions pci_epc_mem_map() and >> pci_epc_mem_unmap() to improve handling of the PCI address mapping >> alignment constraints of endpoint controllers in a controller >> independent manner. >> >> The issue fixed is that the fixed alignment defined by the "align" field >> of struct pci_epc_features is defined for inbound ATU entries (e.g. >> BARs) and is a fixed value, whereas some controllers need a PCI address >> alignment that depends on the PCI address itself. For instance, the >> rk3399 SoC controller in endpoint mode uses the lower bits of the local >> endpoint memory address as the lower bits for the PCI addresses for data >> transfers. That is, when mapping local memory, one must take into >> account the number of bits of the RC PCI address that change from the >> start address of the mapping. >> >> To fix this, the new endpoint controller method .align_addr is >> introduced and called from the new pci_epc_mem_map() function. This >> method is optional and for controllers that do not define it, it is >> assumed that the controller has no PCI address constraint. >> >> The functions pci_epc_mem_map() is a helper function which obtains >> the mapping information, allocates endpoint controller memory according >> to the mapping size obtained and maps the memory. pci_epc_mem_unmap() >> unmaps and frees the endpoint memory. >> >> This series is organized as follows: >> - Patch 1 introduces a small helper to clean up the epc core code >> - Patch 2 improves pci_epc_mem_alloc_addr() >> - Patch 3 introduce the new align_addr() endpoint controller method >> and the epc functions pci_epc_mem_map() and pci_epc_mem_unmap(). >> - Patch 4 documents these new functions. >> - Patch 5 modifies the test endpoint function driver to use >> pci_epc_mem_map() and pci_epc_mem_unmap() to illustrate the use of >> these functions. >> - Finally, patch 6 implements the RK3588 endpoint controller driver >> .align_addr() operation to satisfy that controller PCI address >> alignment constraint. >> >> This patch series was tested using the pci endpoint test driver (as-is >> and a modified version removing memory allocation alignment on the host >> side) as well as with a prototype NVMe endpoint function driver (where >> data transfers use addresses that are never aligned to any specific >> boundary). >> > > Applied to pci/endpoint! Awesome ! Thanks a lot !