Le 22/09/2020 à 11:04, nico.vince@xxxxxxxxx a écrit :
From: Nicolas VINCENT <nicolas.vincent@xxxxxxxxxxx>
the i2c_ram structure is missing the sdmatmp field mentionned in
datasheet for MPC8272 at paragraph 36.5. With this field missing, the
hardware would write past the allocated memory done through
cpm_muram_alloc for the i2c_ram structure and land in memory allocated
for the buffers descriptors corrupting the cbd_bufaddr field. Since this
field is only set during setup(), the first i2c transaction would work
and the following would send data read from an arbitrary memory
location.
Signed-off-by: Nicolas VINCENT <nicolas.vincent@xxxxxxxxxxx>
---
drivers/i2c/busses/i2c-cpm.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/i2c/busses/i2c-cpm.c b/drivers/i2c/busses/i2c-cpm.c
index 1213e1932ccb..c5700addbf65 100644
--- a/drivers/i2c/busses/i2c-cpm.c
+++ b/drivers/i2c/busses/i2c-cpm.c
@@ -64,7 +64,8 @@ struct i2c_ram {
uint txtmp; /* Internal */
char res1[4]; /* Reserved */
ushort rpbase; /* Relocation pointer */
- char res2[2]; /* Reserved */
+ char res2[6]; /* Reserved */
+ uint sdmatmp; /* Internal */
On CPM1, I2C param RAM has size 0x30 (offset 0x1c80-0x1caf)
Your change overlaps the miscellaneous area that contains CP Microcode
Revision Number, ref MPC885 Reference Manual §18.7.3
};
#define I2COM_START 0x80
Christophe
