ethernet: ucc_geth: fix definition and size of ucc_geth_tx_global_pram
Table 8-53 in the QUICC Engine Reference manual shows definitions of fields up to a size of 192 bytes, not just 128. But in table 8-111, one does find the text Base Address of the Global Transmitter Parameter RAM Page. [...] The user needs to allocate 128 bytes for this page. The address must be aligned to the page size. I've checked both rev. 7 (11/2015) and rev. 9 (05/2018) of the manual; they both have this inconsistency (and the table numbers are the same). Adding a bit of debug printing, on my board the struct ucc_geth_tx_global_pram is allocated at offset 0x880, while the (opaque) ucc_geth_thread_data_tx gets allocated immediately afterwards, at 0x900. So whatever the engine writes into the thread data overlaps with the tail of the global tx pram (and devmem says that something does get written during a simple ping). I haven't observed any failure that could be attributed to this, but it seems to be the kind of thing that would be extremely hard to debug. So extend the struct definition so that we do allocate 192 bytes. Signed-off-by:Rasmus Villemoes <rasmus.villemoes@prevas.dk> Signed-off-by:
Jakub Kicinski <kuba@kernel.org>
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1385ae5c