| Message ID | 20241011120115.89756-4-dlemoal@kernel.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Improve PCI memory mapping API | expand |
On Fri, Oct 11, 2024 at 09:01:12PM +0900, Damien Le Moal wrote: > Some endpoint controllers have requirements on the alignment of the > controller physical memory address that must be used to map a RC PCI > address region. For instance, the endpoint controller of the RK3399 SoC > uses at most the lower 20 bits of a physical memory address region as > the lower bits of a RC PCI address region. For mapping a PCI address > region of size bytes starting from pci_addr, the exact number of > address bits used is the number of address bits changing in the address > range [pci_addr..pci_addr + size - 1]. For this example, this creates > the following constraints: > 1) The offset into the controller physical memory allocated for a > mapping depends on the mapping size *and* the starting PCI address > for the mapping. > 2) A mapping size cannot exceed the controller windows size (1MB) minus > the offset needed into the allocated physical memory, which can end > up being a smaller size than the desired mapping size. > > Handling these constraints independently of the controller being used > in an endpoint function driver is not possible with the current EPC > API as only the ->align field in struct pci_epc_features is provided > but used for BAR (inbound ATU mappings) mapping only. A new API is > needed for function drivers to discover mapping constraints and handle > non-static requirements based on the RC PCI address range to access. > > Introduce endpoint controller operation ->get_mem_map() to allow > the EPC core functions to obtain the size and the offset into a > controller address region that must be allocated and mapped to access > a RC PCI address region. The size of the mapping provided by the > get_mem_map() operation can then be used as the size argument for the > function pci_epc_mem_alloc_addr() and the offset into the allocated > controller memory provided can be used to correctly handle data > transfers. For endpoint controllers that have PCI address alignment > constraints, get_mem_map() may indicate upon return an effective PCI > address region size that is smaller (but not 0) than the requested PCI > address region size. > > The controller ->get_mem_map() operation is optional: controllers that > do not have any alignment constraints for mapping RC PCI address regions > do not need to implement this operation. For such controllers, it is > always assumed that the mapping size is equal to the requested size of > the PCI region and that the mapping offset is 0. > > The function pci_epc_mem_map() is introduced to use this new controller > operation (if it is defined) to handle controller memory allocation and > mapping to a RC PCI address region in endpoint function drivers. > > This function first uses the ->get_mem_map() controller operation to > determine the controller memory address size (and offset into) needed > for mapping an RC PCI address region. The result of this function > operation is used to allocate a controller physical memory region using > pci_epc_mem_alloc_addr() and then to map that memory to the RC PCI > address space with pci_epc_map_addr(). > > Since ->get_mem_map() () may indicate that not all of a RC PCI > address region can be mapped, pci_epc_mem_map() may only partially map > the RC PCI address region specified. It is the responsibility of the > caller (an endpoint function driver) to handle such smaller mapping > by repeatedly using pci_epc_mem_map() over the desried PCI address > range. > > The counterpart of pci_epc_mem_map() to unmap and free the controller > memory address region is pci_epc_mem_unmap(). > > Both functions as well as the ->get_mem_map() controller operation > operate using the new struct pci_epc_map data structure. This new > structure represents a mapping PCI address, mapping effective size, the > size and offset into the controller memory needed for the mapping as > well as the physical and virtual CPU addresses of the mapping (phys_base > and virt_base fields). For convenience, the physical and virtual CPU > addresses within that mapping to access the target RC PCI address region > are also provided (phys_addr and virt_addr fields). > > Endpoint function drivers can use struct pci_epc_map to access the > mapped RC PCI address region using the ->virt_addr and ->pci_size > fields. > > Co-developed-by: Rick Wertenbroek <rick.wertenbroek@gmail.com> > Signed-off-by: Rick Wertenbroek <rick.wertenbroek@gmail.com> > Signed-off-by: Damien Le Moal <dlemoal@kernel.org> > --- > drivers/pci/endpoint/pci-epc-core.c | 126 ++++++++++++++++++++++++++++ > include/linux/pci-epc.h | 39 +++++++++ > 2 files changed, 165 insertions(+) > > diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c > index b854f1bab26f..b6bf6d9f9f85 100644 > --- a/drivers/pci/endpoint/pci-epc-core.c > +++ b/drivers/pci/endpoint/pci-epc-core.c > @@ -466,6 +466,132 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > } > EXPORT_SYMBOL_GPL(pci_epc_map_addr); > > +/* > + * Determine the actual PCI address range that should be mapped to access > + * @pci_size from @pci_addr. This is done using the controller get_mem_map > + * operation if that operation is defined. Otherwise, simply assume that the > + * controller has no mapping alignment constraint and return the requested range > + * as-is. > + */ > +static int pci_epc_get_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > + u64 pci_addr, size_t pci_size, > + struct pci_epc_map *map) > +{ > + int ret; > + > + /* > + * Initialize and remember the PCI address region to be mapped. The > + * controller ->get_mem_map() operation may change the map->pci_size to a > + * smaller value. > + */ > + memset(map, 0, sizeof(*map)); > + map->pci_addr = pci_addr; > + map->pci_size = pci_size; > + > + if (!epc->ops->get_mem_map) { > + /* > + * Assume that the EP controller has no alignment constraint, > + * that is, that the PCI address to map and the size of the > + * controller memory needed for the mapping are the same as > + * specified by the caller. > + */ > + map->map_pci_addr = pci_addr; > + map->map_size = pci_size; > + map->map_ofst = 0; > + return 0; > + } > + > + mutex_lock(&epc->lock); > + ret = epc->ops->get_mem_map(epc, func_no, vfunc_no, map); > + mutex_unlock(&epc->lock); > + > + return ret; > +} > + > +/** > + * pci_epc_mem_map() - allocate and map a PCI address to a CPU address > + * @epc: the EPC device on which the CPU address is to be allocated and mapped > + * @func_no: the physical endpoint function number in the EPC device > + * @vfunc_no: the virtual endpoint function number in the physical function > + * @pci_addr: PCI address to which the CPU address should be mapped > + * @pci_size: the number of bytes to map starting from @pci_addr > + * @map: where to return the mapping information > + * > + * Allocate a controller memory address region and map it to a RC PCI address > + * region, taking into account the controller physical address mapping > + * constraints using pci_epc_get_mem_map(). > + * The effective size of the PCI address range mapped from @pci_addr is > + * indicated by @map->pci_size. This size may be less than the requested > + * @pci_size. The local virtual CPU address for the mapping is indicated by > + * @map->virt_addr (@map->phys_addr indicates the physical address). > + * The size and CPU address of the controller memory allocated and mapped are > + * respectively indicated by @map->map_size and @map->virt_base (and > + * @map->phys_base). > + * > + * Returns 0 on success and a negative error code in case of error. > + */ > +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > + u64 pci_addr, size_t pci_size, struct pci_epc_map *map) > +{ > + int ret; > + > + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) > + return -EINVAL; > + > + if (!pci_size || !map) > + return -EINVAL; > + > + ret = pci_epc_get_mem_map(epc, func_no, vfunc_no, > + pci_addr, pci_size, map); > + if (ret) > + return ret; > + > + map->virt_base = pci_epc_mem_alloc_addr(epc, &map->phys_base, > + map->map_size); > + if (!map->virt_base) > + return -ENOMEM; > + > + map->phys_addr = map->phys_base + map->map_ofst; > + map->virt_addr = map->virt_base + map->map_ofst; > + > + ret = pci_epc_map_addr(epc, func_no, vfunc_no, map->phys_base, > + map->map_pci_addr, map->map_size); > + if (ret) { > + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, > + map->map_size); > + map->virt_base = 0; As reported by the kernel test robot on both v3 and v4, this should be: map->virt_base = NULL; otherwise you introduce a new sparse warning. > + return ret; > + } > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(pci_epc_mem_map); > + > +/** > + * pci_epc_mem_unmap() - unmap and free a CPU address region > + * @epc: the EPC device on which the CPU address is allocated and mapped > + * @func_no: the physical endpoint function number in the EPC device > + * @vfunc_no: the virtual endpoint function number in the physical function > + * @map: the mapping information > + * > + * Unmap and free a CPU address region that was allocated and mapped with > + * pci_epc_mem_map(). > + */ > +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > + struct pci_epc_map *map) > +{ > + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) > + return; > + > + if (!map || !map->virt_base) > + return; > + > + pci_epc_unmap_addr(epc, func_no, vfunc_no, map->phys_base); > + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, > + map->map_size); > +} > +EXPORT_SYMBOL_GPL(pci_epc_mem_unmap); > + > /** > * pci_epc_clear_bar() - reset the BAR > * @epc: the EPC device for which the BAR has to be cleared > diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h > index 42ef06136bd1..b5f5c1eb54c5 100644 > --- a/include/linux/pci-epc.h > +++ b/include/linux/pci-epc.h > @@ -32,11 +32,44 @@ pci_epc_interface_string(enum pci_epc_interface_type type) > } > } > > +/** > + * struct pci_epc_map - information about EPC memory for mapping a RC PCI > + * address range > + * @pci_addr: start address of the RC PCI address range to map > + * @pci_size: size of the RC PCI address range mapped from @pci_addr > + * @map_pci_addr: RC PCI address used as the first address mapped (may be lower > + * than @pci_addr) > + * @map_size: size of the controller memory needed for mapping the RC PCI address > + * range @pci_addr..@pci_addr+@pci_size > + * @map_ofst: offset into the mapped controller memory to access @pci_addr > + * @phys_base: base physical address of the allocated EPC memory for mapping the > + * RC PCI address range > + * @phys_addr: physical address at which @pci_addr is mapped > + * @virt_base: base virtual address of the allocated EPC memory for mapping the > + * RC PCI address range > + * @virt_addr: virtual address at which @pci_addr is mapped > + */ > +struct pci_epc_map { > + phys_addr_t pci_addr; > + size_t pci_size; > + > + phys_addr_t map_pci_addr; > + size_t map_size; > + phys_addr_t map_ofst; > + > + phys_addr_t phys_base; > + phys_addr_t phys_addr; > + void __iomem *virt_base; > + void __iomem *virt_addr; > +}; > + > /** > * struct pci_epc_ops - set of function pointers for performing EPC operations > * @write_header: ops to populate configuration space header > * @set_bar: ops to configure the BAR > * @clear_bar: ops to reset the BAR > + * @get_mem_map: operation to get the size and offset into a controller memory > + * window needed to map an RC PCI address region > * @map_addr: ops to map CPU address to PCI address > * @unmap_addr: ops to unmap CPU address and PCI address > * @set_msi: ops to set the requested number of MSI interrupts in the MSI > @@ -61,6 +94,8 @@ struct pci_epc_ops { > struct pci_epf_bar *epf_bar); > void (*clear_bar)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > struct pci_epf_bar *epf_bar); > + int (*get_mem_map)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > + struct pci_epc_map *map); > int (*map_addr)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > phys_addr_t addr, u64 pci_addr, size_t size); > void (*unmap_addr)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > @@ -278,6 +313,10 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, > phys_addr_t *phys_addr, size_t size); > void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr, > void __iomem *virt_addr, size_t size); > +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > + u64 pci_addr, size_t pci_size, struct pci_epc_map *map); > +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > + struct pci_epc_map *map); > > #else > static inline void pci_epc_init_notify(struct pci_epc *epc) > -- > 2.47.0 >
On 10/11/24 21:07, Niklas Cassel wrote: >> +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, >> + u64 pci_addr, size_t pci_size, struct pci_epc_map *map) >> +{ >> + int ret; >> + >> + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) >> + return -EINVAL; >> + >> + if (!pci_size || !map) >> + return -EINVAL; >> + >> + ret = pci_epc_get_mem_map(epc, func_no, vfunc_no, >> + pci_addr, pci_size, map); >> + if (ret) >> + return ret; >> + >> + map->virt_base = pci_epc_mem_alloc_addr(epc, &map->phys_base, >> + map->map_size); >> + if (!map->virt_base) >> + return -ENOMEM; >> + >> + map->phys_addr = map->phys_base + map->map_ofst; >> + map->virt_addr = map->virt_base + map->map_ofst; >> + >> + ret = pci_epc_map_addr(epc, func_no, vfunc_no, map->phys_base, >> + map->map_pci_addr, map->map_size); >> + if (ret) { >> + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, >> + map->map_size); >> + map->virt_base = 0; > > As reported by the kernel test robot on both v3 and v4, this should be: > map->virt_base = NULL; > otherwise you introduce a new sparse warning. Oops. Missed that... OK, sending v6 with this removed as that is not necessary anyway. > > >> + return ret; >> + } >> + >> + return 0; >> +} >> +EXPORT_SYMBOL_GPL(pci_epc_mem_map); >> + >> +/** >> + * pci_epc_mem_unmap() - unmap and free a CPU address region >> + * @epc: the EPC device on which the CPU address is allocated and mapped >> + * @func_no: the physical endpoint function number in the EPC device >> + * @vfunc_no: the virtual endpoint function number in the physical function >> + * @map: the mapping information >> + * >> + * Unmap and free a CPU address region that was allocated and mapped with >> + * pci_epc_mem_map(). >> + */ >> +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, >> + struct pci_epc_map *map) >> +{ >> + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) >> + return; >> + >> + if (!map || !map->virt_base) >> + return; >> + >> + pci_epc_unmap_addr(epc, func_no, vfunc_no, map->phys_base); >> + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, >> + map->map_size); >> +} >> +EXPORT_SYMBOL_GPL(pci_epc_mem_unmap); >> + >> /** >> * pci_epc_clear_bar() - reset the BAR >> * @epc: the EPC device for which the BAR has to be cleared >> diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h >> index 42ef06136bd1..b5f5c1eb54c5 100644 >> --- a/include/linux/pci-epc.h >> +++ b/include/linux/pci-epc.h >> @@ -32,11 +32,44 @@ pci_epc_interface_string(enum pci_epc_interface_type type) >> } >> } >> >> +/** >> + * struct pci_epc_map - information about EPC memory for mapping a RC PCI >> + * address range >> + * @pci_addr: start address of the RC PCI address range to map >> + * @pci_size: size of the RC PCI address range mapped from @pci_addr >> + * @map_pci_addr: RC PCI address used as the first address mapped (may be lower >> + * than @pci_addr) >> + * @map_size: size of the controller memory needed for mapping the RC PCI address >> + * range @pci_addr..@pci_addr+@pci_size >> + * @map_ofst: offset into the mapped controller memory to access @pci_addr >> + * @phys_base: base physical address of the allocated EPC memory for mapping the >> + * RC PCI address range >> + * @phys_addr: physical address at which @pci_addr is mapped >> + * @virt_base: base virtual address of the allocated EPC memory for mapping the >> + * RC PCI address range >> + * @virt_addr: virtual address at which @pci_addr is mapped >> + */ >> +struct pci_epc_map { >> + phys_addr_t pci_addr; >> + size_t pci_size; >> + >> + phys_addr_t map_pci_addr; >> + size_t map_size; >> + phys_addr_t map_ofst; >> + >> + phys_addr_t phys_base; >> + phys_addr_t phys_addr; >> + void __iomem *virt_base; >> + void __iomem *virt_addr; >> +}; >> + >> /** >> * struct pci_epc_ops - set of function pointers for performing EPC operations >> * @write_header: ops to populate configuration space header >> * @set_bar: ops to configure the BAR >> * @clear_bar: ops to reset the BAR >> + * @get_mem_map: operation to get the size and offset into a controller memory >> + * window needed to map an RC PCI address region >> * @map_addr: ops to map CPU address to PCI address >> * @unmap_addr: ops to unmap CPU address and PCI address >> * @set_msi: ops to set the requested number of MSI interrupts in the MSI >> @@ -61,6 +94,8 @@ struct pci_epc_ops { >> struct pci_epf_bar *epf_bar); >> void (*clear_bar)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, >> struct pci_epf_bar *epf_bar); >> + int (*get_mem_map)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, >> + struct pci_epc_map *map); >> int (*map_addr)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, >> phys_addr_t addr, u64 pci_addr, size_t size); >> void (*unmap_addr)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, >> @@ -278,6 +313,10 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, >> phys_addr_t *phys_addr, size_t size); >> void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr, >> void __iomem *virt_addr, size_t size); >> +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, >> + u64 pci_addr, size_t pci_size, struct pci_epc_map *map); >> +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, >> + struct pci_epc_map *map); >> >> #else >> static inline void pci_epc_init_notify(struct pci_epc *epc) >> -- >> 2.47.0 >>
On Fri, Oct 11, 2024 at 02:07:07PM +0200, Niklas Cassel wrote: > On Fri, Oct 11, 2024 at 09:01:12PM +0900, Damien Le Moal wrote: (snip) > > +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > > + u64 pci_addr, size_t pci_size, struct pci_epc_map *map) > > +{ > > + int ret; > > + > > + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) > > + return -EINVAL; > > + > > + if (!pci_size || !map) > > + return -EINVAL; > > + > > + ret = pci_epc_get_mem_map(epc, func_no, vfunc_no, > > + pci_addr, pci_size, map); > > + if (ret) > > + return ret; > > + > > + map->virt_base = pci_epc_mem_alloc_addr(epc, &map->phys_base, > > + map->map_size); > > + if (!map->virt_base) > > + return -ENOMEM; > > + > > + map->phys_addr = map->phys_base + map->map_ofst; > > + map->virt_addr = map->virt_base + map->map_ofst; > > + > > + ret = pci_epc_map_addr(epc, func_no, vfunc_no, map->phys_base, > > + map->map_pci_addr, map->map_size); > > + if (ret) { > > + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, > > + map->map_size); > > + map->virt_base = 0; > > As reported by the kernel test robot on both v3 and v4, this should be: > map->virt_base = NULL; > otherwise you introduce a new sparse warning. With that nit fixed: Reviewed-by: Niklas Cassel <cassel@kernel.org>
On Fri, Oct 11, 2024 at 09:21:29PM +0900, Damien Le Moal wrote: > On 10/11/24 21:07, Niklas Cassel wrote: > >> +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > >> + u64 pci_addr, size_t pci_size, struct pci_epc_map *map) > >> +{ > >> + int ret; > >> + > >> + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) > >> + return -EINVAL; > >> + > >> + if (!pci_size || !map) > >> + return -EINVAL; > >> + > >> + ret = pci_epc_get_mem_map(epc, func_no, vfunc_no, > >> + pci_addr, pci_size, map); > >> + if (ret) > >> + return ret; > >> + > >> + map->virt_base = pci_epc_mem_alloc_addr(epc, &map->phys_base, > >> + map->map_size); > >> + if (!map->virt_base) > >> + return -ENOMEM; > >> + > >> + map->phys_addr = map->phys_base + map->map_ofst; > >> + map->virt_addr = map->virt_base + map->map_ofst; > >> + > >> + ret = pci_epc_map_addr(epc, func_no, vfunc_no, map->phys_base, > >> + map->map_pci_addr, map->map_size); > >> + if (ret) { > >> + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, > >> + map->map_size); > >> + map->virt_base = 0; > > > > As reported by the kernel test robot on both v3 and v4, this should be: > > map->virt_base = NULL; > > otherwise you introduce a new sparse warning. > > Oops. Missed that... OK, sending v6 with this removed as that is not necessary > anyway. > Please incorporate this in v6. - Mani
diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index b854f1bab26f..b6bf6d9f9f85 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -466,6 +466,132 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no, } EXPORT_SYMBOL_GPL(pci_epc_map_addr); +/* + * Determine the actual PCI address range that should be mapped to access + * @pci_size from @pci_addr. This is done using the controller get_mem_map + * operation if that operation is defined. Otherwise, simply assume that the + * controller has no mapping alignment constraint and return the requested range + * as-is. + */ +static int pci_epc_get_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + u64 pci_addr, size_t pci_size, + struct pci_epc_map *map) +{ + int ret; + + /* + * Initialize and remember the PCI address region to be mapped. The + * controller ->get_mem_map() operation may change the map->pci_size to a + * smaller value. + */ + memset(map, 0, sizeof(*map)); + map->pci_addr = pci_addr; + map->pci_size = pci_size; + + if (!epc->ops->get_mem_map) { + /* + * Assume that the EP controller has no alignment constraint, + * that is, that the PCI address to map and the size of the + * controller memory needed for the mapping are the same as + * specified by the caller. + */ + map->map_pci_addr = pci_addr; + map->map_size = pci_size; + map->map_ofst = 0; + return 0; + } + + mutex_lock(&epc->lock); + ret = epc->ops->get_mem_map(epc, func_no, vfunc_no, map); + mutex_unlock(&epc->lock); + + return ret; +} + +/** + * pci_epc_mem_map() - allocate and map a PCI address to a CPU address + * @epc: the EPC device on which the CPU address is to be allocated and mapped + * @func_no: the physical endpoint function number in the EPC device + * @vfunc_no: the virtual endpoint function number in the physical function + * @pci_addr: PCI address to which the CPU address should be mapped + * @pci_size: the number of bytes to map starting from @pci_addr + * @map: where to return the mapping information + * + * Allocate a controller memory address region and map it to a RC PCI address + * region, taking into account the controller physical address mapping + * constraints using pci_epc_get_mem_map(). + * The effective size of the PCI address range mapped from @pci_addr is + * indicated by @map->pci_size. This size may be less than the requested + * @pci_size. The local virtual CPU address for the mapping is indicated by + * @map->virt_addr (@map->phys_addr indicates the physical address). + * The size and CPU address of the controller memory allocated and mapped are + * respectively indicated by @map->map_size and @map->virt_base (and + * @map->phys_base). + * + * Returns 0 on success and a negative error code in case of error. + */ +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + u64 pci_addr, size_t pci_size, struct pci_epc_map *map) +{ + int ret; + + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) + return -EINVAL; + + if (!pci_size || !map) + return -EINVAL; + + ret = pci_epc_get_mem_map(epc, func_no, vfunc_no, + pci_addr, pci_size, map); + if (ret) + return ret; + + map->virt_base = pci_epc_mem_alloc_addr(epc, &map->phys_base, + map->map_size); + if (!map->virt_base) + return -ENOMEM; + + map->phys_addr = map->phys_base + map->map_ofst; + map->virt_addr = map->virt_base + map->map_ofst; + + ret = pci_epc_map_addr(epc, func_no, vfunc_no, map->phys_base, + map->map_pci_addr, map->map_size); + if (ret) { + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, + map->map_size); + map->virt_base = 0; + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(pci_epc_mem_map); + +/** + * pci_epc_mem_unmap() - unmap and free a CPU address region + * @epc: the EPC device on which the CPU address is allocated and mapped + * @func_no: the physical endpoint function number in the EPC device + * @vfunc_no: the virtual endpoint function number in the physical function + * @map: the mapping information + * + * Unmap and free a CPU address region that was allocated and mapped with + * pci_epc_mem_map(). + */ +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + struct pci_epc_map *map) +{ + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) + return; + + if (!map || !map->virt_base) + return; + + pci_epc_unmap_addr(epc, func_no, vfunc_no, map->phys_base); + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, + map->map_size); +} +EXPORT_SYMBOL_GPL(pci_epc_mem_unmap); + /** * pci_epc_clear_bar() - reset the BAR * @epc: the EPC device for which the BAR has to be cleared diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index 42ef06136bd1..b5f5c1eb54c5 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -32,11 +32,44 @@ pci_epc_interface_string(enum pci_epc_interface_type type) } } +/** + * struct pci_epc_map - information about EPC memory for mapping a RC PCI + * address range + * @pci_addr: start address of the RC PCI address range to map + * @pci_size: size of the RC PCI address range mapped from @pci_addr + * @map_pci_addr: RC PCI address used as the first address mapped (may be lower + * than @pci_addr) + * @map_size: size of the controller memory needed for mapping the RC PCI address + * range @pci_addr..@pci_addr+@pci_size + * @map_ofst: offset into the mapped controller memory to access @pci_addr + * @phys_base: base physical address of the allocated EPC memory for mapping the + * RC PCI address range + * @phys_addr: physical address at which @pci_addr is mapped + * @virt_base: base virtual address of the allocated EPC memory for mapping the + * RC PCI address range + * @virt_addr: virtual address at which @pci_addr is mapped + */ +struct pci_epc_map { + phys_addr_t pci_addr; + size_t pci_size; + + phys_addr_t map_pci_addr; + size_t map_size; + phys_addr_t map_ofst; + + phys_addr_t phys_base; + phys_addr_t phys_addr; + void __iomem *virt_base; + void __iomem *virt_addr; +}; + /** * struct pci_epc_ops - set of function pointers for performing EPC operations * @write_header: ops to populate configuration space header * @set_bar: ops to configure the BAR * @clear_bar: ops to reset the BAR + * @get_mem_map: operation to get the size and offset into a controller memory + * window needed to map an RC PCI address region * @map_addr: ops to map CPU address to PCI address * @unmap_addr: ops to unmap CPU address and PCI address * @set_msi: ops to set the requested number of MSI interrupts in the MSI @@ -61,6 +94,8 @@ struct pci_epc_ops { struct pci_epf_bar *epf_bar); void (*clear_bar)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, struct pci_epf_bar *epf_bar); + int (*get_mem_map)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + struct pci_epc_map *map); int (*map_addr)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, phys_addr_t addr, u64 pci_addr, size_t size); void (*unmap_addr)(struct pci_epc *epc, u8 func_no, u8 vfunc_no, @@ -278,6 +313,10 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, phys_addr_t *phys_addr, size_t size); void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr, void __iomem *virt_addr, size_t size); +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + u64 pci_addr, size_t pci_size, struct pci_epc_map *map); +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + struct pci_epc_map *map); #else static inline void pci_epc_init_notify(struct pci_epc *epc)