When a resource table is loaded by an external entity such as U-boot or OP-TEE, we do not necessary get the device address(da) but the physical address(pa). This helper performs similar translation than the rproc_da_to_va() but based on a physical address.
Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@foss.st.com --- drivers/remoteproc/remoteproc_core.c | 74 +++++++++++++++++++++++++++- include/linux/remoteproc.h | 3 ++ 2 files changed, 75 insertions(+), 2 deletions(-)
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index f276956f2c5c..3fdec0336fd6 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -230,6 +230,77 @@ void *rproc_da_to_va(struct rproc *rproc, u64 da, size_t len, bool *is_iomem) } EXPORT_SYMBOL(rproc_da_to_va);
+/** + * rproc_pa_to_va() - lookup the kernel virtual address for a physical address of a remoteproc + * memory + * + * @rproc: handle of a remote processor + * @pa: remoteproc physical address + * @len: length of the memory region @pa is pointing to + * @is_iomem: optional pointer filled in to indicate if @da is iomapped memory + * + * Some remote processors will ask us to allocate them physically contiguous + * memory regions (which we call "carveouts"), and map them to specific + * device addresses (which are hardcoded in the firmware). They may also have + * dedicated memory regions internal to the processors, and use them either + * exclusively or alongside carveouts. + * + * They may then ask us to copy objects into specific addresses (e.g. + * code/data sections) or expose us certain symbols in other device address + * (e.g. their trace buffer). + * + * This function is a helper function with which we can go over the allocated + * carveouts and translate specific physical addresses to kernel virtual addresses + * so we can access the referenced memory. This function also allows to perform + * translations on the internal remoteproc memory regions through a platform + * implementation specific pa_to_va ops, if present. + * + * Note: phys_to_virt(iommu_iova_to_phys(rproc->domain, da)) will work too, + * but only on kernel direct mapped RAM memory. Instead, we're just using + * here the output of the DMA API for the carveouts, which should be more + * correct. + * + * Return: a valid kernel address on success or NULL on failure + */ +void *rproc_pa_to_va(struct rproc *rproc, phys_addr_t pa, size_t len, bool *is_iomem) +{ + struct rproc_mem_entry *carveout; + void *ptr = NULL; + + if (rproc->ops->da_to_va) { + ptr = rproc->ops->pa_to_va(rproc, pa, len); + if (ptr) + goto out; + } + + list_for_each_entry(carveout, &rproc->carveouts, node) { + int offset = pa - carveout->dma; + + /* Verify that carveout is allocated */ + if (!carveout->va) + continue; + + /* try next carveout if da is too small */ + if (offset < 0) + continue; + + /* try next carveout if da is too large */ + if (offset + len > carveout->len) + continue; + + ptr = carveout->va + offset; + + if (is_iomem) + *is_iomem = carveout->is_iomem; + + break; + } + +out: + return ptr; +} +EXPORT_SYMBOL(rproc_pa_to_va); + /** * rproc_find_carveout_by_name() - lookup the carveout region by a name * @rproc: handle of a remote processor @@ -724,8 +795,7 @@ static int rproc_alloc_carveout(struct rproc *rproc, * firmware was compiled with. * * In this case, we must use the IOMMU API directly and map - * the memory to the device address as expected by the remote - * processor. + * the memory to the device address as etable * * Obviously such remote processor devices should not be configured * to use the iommu-based DMA API: we expect 'dma' to contain the diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h index b4795698d8c2..28aa62a3b505 100644 --- a/include/linux/remoteproc.h +++ b/include/linux/remoteproc.h @@ -367,6 +367,7 @@ enum rsc_handling_status { * @detach: detach from a device, leaving it powered up * @kick: kick a virtqueue (virtqueue id given as a parameter) * @da_to_va: optional platform hook to perform address translations + * @pa_to_va: optional platform hook to perform address translations * @parse_fw: parse firmware to extract information (e.g. resource table) * @handle_rsc: optional platform hook to handle vendor resources. Should return * RSC_HANDLED if resource was handled, RSC_IGNORED if not handled @@ -391,6 +392,7 @@ struct rproc_ops { int (*detach)(struct rproc *rproc); void (*kick)(struct rproc *rproc, int vqid); void * (*da_to_va)(struct rproc *rproc, u64 da, size_t len, bool *is_iomem); + void * (*pa_to_va)(struct rproc *rproc, phys_addr_t da, size_t len); int (*parse_fw)(struct rproc *rproc, const struct firmware *fw); int (*handle_rsc)(struct rproc *rproc, u32 rsc_type, void *rsc, int offset, int avail); @@ -690,6 +692,7 @@ int rproc_detach(struct rproc *rproc); int rproc_set_firmware(struct rproc *rproc, const char *fw_name); void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type); void *rproc_da_to_va(struct rproc *rproc, u64 da, size_t len, bool *is_iomem); +void *rproc_pa_to_va(struct rproc *rproc, phys_addr_t pa, size_t len, bool *is_iomem);
/* from remoteproc_coredump.c */ void rproc_coredump_cleanup(struct rproc *rproc);