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Date:      Mon, 2 Oct 2017 01:10:35 -0400
From:      Farhan Khan <khanzf@gmail.com>
To:        Andriy Voskoboinyk <s3erios@gmail.com>
Cc:        freebsd-wireless@freebsd.org
Subject:   Re: Register Address Size Mismatch
Message-ID:  <9b0976c3-ad31-0558-a3f4-0177b91fb7e6@gmail.com>
In-Reply-To: <op.y7f2bgwfiew4ia@thinkpad-x220>
References:  <293228d3-c777-d928-8476-ee23ba487c72@gmail.com> <op.y7fd5mltiew4ia@thinkpad-x220> <3f760297-d8dd-a2e0-9fda-e09bff06b11c@gmail.com> <op.y7f2bgwfiew4ia@thinkpad-x220>

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Thank you! That is in the Linux driver here:
http://src.illumos.org/source/xref/linux-master/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/phy.c#_rtl8188e_config_rf_reg

As a matter of completion, is this information publicly available such
as in a chipset document or something you came across from reading the
driver code? I am currently essentially doing replay without fully
understanding how the device works.

On 10/01/2017 03:12 PM, Andriy Voskoboinyk wrote:
> Do you mean 0xFFE address? In vendor driver such 'addresses' are used
> for delay between writes (50 ms for RTL8812A).
> 
>> The issue is in the assignment, not the write/read part. rtwn_rf_prog
>> wants a * uint8_t list, whereas the register size from Linux is a
>> uint32_t (but can cleanly fit into a uint16_t and might just be the
>> default register size on Linux). How do I reconcile those two? I hope I
>> was clearer there.
>>
>> The first column are the Linux registers in question:
>> http://src.illumos.org/source/xref/linux-master/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/table.c#316
>>
>>
>> Thank you for your continued assistance.
>>
>> On 10/01/2017 06:30 AM, Andriy Voskoboinyk wrote:
>>> Hi,
>>>
>>> RF registers are using indirect addressing; you should use
>>> rtwn_rf_write() / rtwn_rf_read() instead.
>>>
>>>
>>>> I am working on porting over a Linux Realtek driver to FreeBSD. I ran
>>>> into a register-size issue.
>>>>
>>>> FreeBSD's PCI-write function is defined as follows:
>>>> rtwn_pci_write_4(struct rtwn_softc *sc, uint16_t addr)
>>>>
>>>> Notice that the second parameter is of type uint16_t.
>>>>
>>>> During initialization, the rtwn driver uses the rtwn_rf_prog structure
>>>> to write a pre-defined list of data to a pre-defined list of registers.
>>>> The structure to hold both lists is defined here:
>>>> http://src.illumos.org/source/xref/freebsd-head/sys/dev/rtwn/if_rtwnreg.h#150.
>>>>
>>>>
>>>> Notice how the second parameter 'reg' is a uint8_t.
>>>>
>>>> The rtwn_pci_write_4's addr is uint16_t, the rtwn_rf_prog's addr is a
>>>> uint8_t. How would I reconcile this type mismatch? Additionally, the
>>>> Linux version of this block of code has all register values as a
>>>> uint32_t. It is not a matter of a cast, because some values definitely
>>>> use more than 1 byte (ie 0xFFE).
>>>>
>>>> Suggestions on how to reconcile and resolve this issue?
>>>>
>>>> Thanks!
>>>> Farhan Khan
>>>> _______________________________________________
>>>> freebsd-wireless@freebsd.org mailing list
>>>> https://lists.freebsd.org/mailman/listinfo/freebsd-wireless
>>>> To unsubscribe, send any mail to
>>>> "freebsd-wireless-unsubscribe@freebsd.org"



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