Re: [PATCH 06/17] coresight: tmc: Make ETR SG table circular

[Suzuki K Poulose]

On 20/10/17 18:11, Julien Thierry wrote:

> > +static int __maybe_unused
> > +tmc_etr_sg_table_rotate(struct etr_sg_table *etr_table, u64 base_offset)
> > +{
> > +ÂÂÂ u32 last_entry, first_entry;
> > +ÂÂÂ u64 last_offset;
> > +ÂÂÂ struct tmc_sg_table *sg_table = etr_table->sg_table;
> > +ÂÂÂ sgte_t *table_ptr = sg_table->table_vaddr;
> > +ÂÂÂ ssize_t buf_size = tmc_sg_table_buf_size(sg_table);
> > +
> > +ÂÂÂ /* Offset should always be SG PAGE_SIZE aligned */
> > +ÂÂÂ if (base_offset & (ETR_SG_PAGE_SIZE - 1)) {
> > +ÂÂÂÂÂÂÂ pr_debug("unaligned base offset %llx\n", base_offset);
> > +ÂÂÂÂÂÂÂ return -EINVAL;
> > +ÂÂÂ }
> > +ÂÂÂ /* Make sure the offset is within the range */
> > +ÂÂÂ if (base_offset < 0 || base_offset > buf_size) {
>
> base_offset is unsigned, so the left operand of the '||' is useless (would've expected the compiler to emit a warning for this).
>
> > +ÂÂÂÂÂÂÂ base_offset = (base_offset + buf_size) % buf_size;
> > +ÂÂÂÂÂÂÂ pr_debug("Resetting offset to %llx\n", base_offset);
> > +ÂÂÂ }
> > +ÂÂÂ first_entry = tmc_etr_sg_offset_to_table_index(base_offset);
> > +ÂÂÂ if (first_entry == etr_table->first_entry) {
> > +ÂÂÂÂÂÂÂ pr_debug("Head is already at %llx, skipping\n", base_offset);
> > +ÂÂÂÂÂÂÂ return 0;
> > +ÂÂÂ }
> > +
> > +ÂÂÂ /* Last entry should be the previous one to the new "base" */
> > +ÂÂÂ last_offset = ((base_offset - ETR_SG_PAGE_SIZE) + buf_size) % buf_size;
> > +ÂÂÂ last_entry = tmc_etr_sg_offset_to_table_index(last_offset);
> > +
> > +ÂÂÂ /* Reset the current Last page to Normal and new Last page to NORMAL */
>
> Current Last page to NORMAL and new Last page to LAST?

Thanks again, will fix them

Cheers
Suzuki