From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oleksij Rempel Date: Fri, 19 Dec 2014 16:14:06 +0100 Subject: [ath9k-devel] AR9271 Clock rate In-Reply-To: <54943FDD.5090401@rempel-privat.de> References: <5494273A.4090901@rempel-privat.de> <54943FDD.5090401@rempel-privat.de> Message-ID: <549440BE.2010006@rempel-privat.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ath9k-devel@lists.ath9k.org Am 19.12.2014 um 16:10 schrieb Oleksij Rempel: > Am 19.12.2014 um 14:53 schrieb Adrian Nicolau: >> I understand this, and neither was I expecting that the REG_WRITE would >> overwrite the common->clockrate value. My question can be rephrased: Why >> are there two different clock rate values defined for AR9271: one of 117 >> MHz which is written in the registry, and the other of 44 MHz which is >> set in the ath9k_hw_set_clockrate function? There is no checking done in >> this function for AR_SREV_9271 like the one made for AR_SREV_9287 [1] >> which sets the clock at 117MHz as well. >> >> [1] https://github.com/torvalds/linux/blob/master/drivers/net/wireless/ath/ath9k/hw.c#L46 > > Ach... ok. you right. > > pll related changes from the host are ignored: > https://github.com/olerem/open-ath9k-htc-firmware/blob/master/target_firmware/wlan/if_ath.c#L1456 Note about this FW... not all functions do what they actually should do, so always check the source. >> Thank you, >> Adrian >> >> On Fri, Dec 19, 2014 at 3:25 PM, Oleksij Rempel > > wrote: >> >> Am 19.12.2014 um 10:21 schrieb Adrian Nicolau: >> > Hello, >> > >> > I am using a TL-WN722N for a Wi-Fi ToF project; the SOC is AR9271 >> and I >> > obtained the ath9k_htc source code via backports version 3.17.1-1. For >> > ToF measurements, the higher the clock rate of the SOC, the >> better, and >> > I know that AR9271 has a 117 MHz one. >> > Reading through the code, in file ath/ath9k/hw.c, function >> > ath9k_hw_set_clockrate [1] there is no entry for AS_SREV_9271, leaving >> > the clockrate to be 44MHz in the common structure and throughout >> execution. >> > The 117MHz setting is done later in the code by writing to a >> registry [2]. >> > >> > I am wondering why the writing to the registry is not reflected in the >> > common structure as well. >> > >> > [1] >> https://github.com/torvalds/linux/blob/master/drivers/net/wireless/ath/ath9k/hw.c#L39 >> > [2] >> https://github.com/torvalds/linux/blob/master/drivers/net/wireless/ath/ath9k/hw.c#L864 >> >> Because you are writing to wrong offset. >> >> REG_WRITE will do it to a memory region mapped to mac core for this SoC. >> -- >> Regards, >> Oleksij >> > > > > > _______________________________________________ > ath9k-devel mailing list > ath9k-devel at lists.ath9k.org > https://lists.ath9k.org/mailman/listinfo/ath9k-devel > -- Regards, Oleksij -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 213 bytes Desc: OpenPGP digital signature Url : http://lists.ath9k.org/pipermail/ath9k-devel/attachments/20141219/44539c46/attachment.pgp