On Fri, 6 Feb 2009 11:45:29 +0900
Isaku Yamahata <yamahata@xxxxxxxxxxxxx> wrote:
> On Thu, Feb 05, 2009 at 07:23:11PM +0900, Yuji Shimada wrote:
> > We can clean up the existing code in pass-through.c in the same
> > manner. I will submit the patch to clean up the code.
>
> Thank you for clean up.
> There are another logic duplications with mask operations.
> I suppose helper functions like the following will help
> to reduce the code more.
>
> thanks,
>
> static void __pt_read_{byte, word, long}(uint{8, 16, 32}_t *value,
> uint{8, 16, 32}_t dev_value,
> uint{8, 16, 32}_t emu_mask,
> uint{8, 16, 32}_t valid_mask)
> {
> uint{8, 16, 32}_t valid_emu_mask = emu_mask & valid_mask;
> *value = ((*value & ~valid_emu_mask) | (dev_data & valid_emu_mask));
> }
>
> static void __pt_write_cfg_{byte, word, long}(struct pt_reg_tbl *cfg_entry,
> uint{8, 16, 32}_t value
> uint{8, 16, 32}_t emu_mask,
> uint{8, 16, 32}_t ro_mask,
> uint{8, 16, 32}_t valid_mask)
> {
> uint{8, 16, 32}_t writable_mask = emu_mask & ~ro_mask & valid_mask;
> cfg_entry->data = ((value & writable_mask) |
> (cfg_entry->data & ~writable_mask));
> }
>
> static void __pt_write_{byte, word, long}(uint{8, 16, 32}_t *value,
> uint{8, 16, 32}_t dev_value,
> uint{8, 16, 32}_t emu_mask,
> uint{8, 16, 32}_t valid_mask)
> {
> uint{8, 16, 32}_t throughable_mask = ~emu_mask & valid_mask;
> *value = ((*value & throughable_mask) | (dev_value & ~throughable_mask));
> }
I realize the duplications with mask operations.
I have already introduced PT_MERGE_VALUE macro with the previous
patch. I'd like to create the new patch which cleanups them using
PT_MERGE_VALUE macro.
Is this acceptable?
These are examples.
Returned value to guest software on reading:
*value = PT_MERGE_VALUE(*value, dev_value, emu_mask & valid_mask);
Emulated value on writing.
cfg_entry->data = PT_MERGE_VALUE(value, cfg_entry->data,
emu_mask & ~ro_mask & valid_mask)
Written value to actual device on writing:
*value = PT_MERGE_VALUE(*value, dev_value, ~emu_mask & valid_mask);
Thanks,
--
Yuji Shimada
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