[PATCH v10 1/7] remoteproc: core: Introduce rproc_pa_to_va helper

Arnaud Pouliquen
2024-10-07T13:36:49Z

When a resource table is loaded by an external entity such as U-boot or
OP-TEE, we do not necessarily 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 | 46 ++++++++++++++++++++++++++++
include/linux/remoteproc.h | 1 +
2 files changed, 47 insertions(+)

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index f276956f2c5c..ace11ea17097 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -230,6 +230,52 @@ 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
+ *
+ * This function is a helper function similar to rproc_da_to_va() but it deals with physical
+ * addresses instead of device addresses.
+ *
+ * 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;
+
+ 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;
+ }
+
+ 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
diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index b4795698d8c2..8fd0d7f63c8e 100644
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -690,6 +690,7 @@ 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);
--
2.25.1