In venus_boot(), we pass a pointer to a phys_addr_t
into dmam_alloc_coherent, which the compiler warns about:
platform/qcom/venus/firmware.c: In function 'venus_boot':
platform/qcom/venus/firmware.c:63:49: error: passing argument 3 of
'dmam_alloc_coherent' from incompatible pointer type
[-Werror=incompatible-pointer-types]
The returned DMA address is later passed on to a function that
takes a phys_addr_t, so it's clearly wrong to use the DMA
mapping interface here: the memory may be uncached, or the
address may be completely wrong if there is an IOMMU connected
to the device.
My interpretation is that using dmam_alloc_coherent() had two
purposes:
a) get a chunk of consecutive memory that may be larger than
the limit for kmalloc()
b) use the devres infrastructure to simplify the unwinding
in the error case.
I think ideally we'd use a devres-based version of
alloc_pages_exact() here, but since that doesn't exist,
let's use devm_get_free_pages() instead. This wastes a little
memory as the size gets rounded up to a power of two, but
is otherwise harmless. If we want to save memory here, calling
devm_free_pages() to release the memory once it is no longer
needed is probably better anyway.
Fixes: af2c3834c8ca ("[media] media: venus: adding core part and helper
functions")
Signed-off-by: Arnd Bergmann <a...@arndb.de>
---
The same problem exists in the drm driver, as of commit 7c65817e6d38
("drm/msm: gpu: Enable zap shader for A5XX"), and I submitted the
same patch for that already.
---
drivers/media/platform/qcom/venus/firmware.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/media/platform/qcom/venus/firmware.c
b/drivers/media/platform/qcom/venus/firmware.c
index 1b1a4f355918..76edb9f60311 100644
--- a/drivers/media/platform/qcom/venus/firmware.c
+++ b/drivers/media/platform/qcom/venus/firmware.c
@@ -60,11 +60,13 @@ int venus_boot(struct device *parent, struct device
*fw_dev, const char *fwname)
mem_size = VENUS_FW_MEM_SIZE;
- mem_va = dmam_alloc_coherent(fw_dev, mem_size, &mem_phys, GFP_KERNEL);
+ mem_va = (void *)devm_get_free_pages(parent, GFP_KERNEL,
+ get_order(mem_size));
if (!mem_va) {
ret = -ENOMEM;
goto err_unreg_device;
}
+ mem_phys = virt_to_phys(mem_va);
ret = request_firmware(&mdt, fwname, fw_dev);
if (ret < 0)
--
2.9.0
