TWxSoftware/twx-linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

drivers: meson: sm: correct meson_sm_* API retval handling

Browse Source 
1. Following the ARM SMC32 calling convention, the return value
from secure monitor is a 32-bit signed integer. This patch changes
the type of the return value of the function meson_sm_call().

2. Now, when meson_sm_call() returns a 32-bit signed integer, we need
to ensure that this value is not negative. It is important to check
that the return value is not negative in both the meson_sm_call_read()
and meson_sm_call_write() functions.

3. Add a comment explaining why it is necessary to check if the SMC
return value is equal to 0 in the function meson_sm_call_read().
It is not obvious when reading this code.

Signed-off-by: Alexey Romanov <avromanov@salutedevices.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20230830140850.17130-1-avromanov@salutedevices.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
This commit is contained in:
Alexey Romanov
2023-08-30 17:08:50 +03:00
committed by Neil Armstrong
parent 0bb80ecc33
commit 0d423c4a78
2 changed files with 14 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files
include/linux/firmware/meson/meson_sm.h
+1 -1
View File
@@ -19,7 +19,7 @@ enum {
struct meson_sm_firmware;
int meson_sm_call(struct meson_sm_firmware *fw, unsigned int cmd_index,
u32 *ret, u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4);
s32 *ret, u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4);
int meson_sm_call_write(struct meson_sm_firmware *fw, void *buffer,
unsigned int b_size, unsigned int cmd_index, u32 arg0,
u32 arg1, u32 arg2, u32 arg3, u32 arg4);