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Date:      Sun, 1 Oct 2017 14:51:04 -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:  <3f760297-d8dd-a2e0-9fda-e09bff06b11c@gmail.com>
In-Reply-To: <op.y7fd5mltiew4ia@thinkpad-x220>
References:  <293228d3-c777-d928-8476-ee23ba487c72@gmail.com> <op.y7fd5mltiew4ia@thinkpad-x220>

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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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