Re: [PATCH v3] can: sja1000: Optimise register accesses

[Alexander Gerasiov <gq@redlab-i.ru>]

Hello Nikita,

On Thu,  8 Sep 2016 11:06:13 +0300
Nikita Edward Baruzdin <nebaruzdin@gmail.com> wrote:

> Since PCI bus width is at least 32 bits, using ioread32()/iowrite32()
> instead of consecutive ioread8()/iowrite8() calls seems reasonable.
> 
> Thus, this patch introduces [read|write]_reg_rep() interface functions
> that are used to read/write CAN ID and payload data.
> 
>   * For plx_pci driver this interface is implemented as
>     plx_pci_[read|write]_reg_rep() that use ioread32()/iowrite32() for
>     register accesses as much as possible to improve driver
> performance.
> 
>   * For other drivers the default implementation,
>     sja1000_[read|write]_reg_rep(), is used for now. These functions
>     still access registers in a series of ioread8()/iowrite8() calls.

This looks OK for me. (I hope you didn't forget to run tests with this
variant. And with default implementation of rep functions too.)


It would be good if someone run tests with other plx_pci based adapters
(they should also work with 32 bit access via PCI, but who knows).
Tests with other sja1000 cards and on big-endian boxes are welcome too.



-- 
Best regards,
 Alexander Gerasiov

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