From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wm0-f65.google.com ([74.125.82.65]:53002 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754166AbeCSOKY (ORCPT ); Mon, 19 Mar 2018 10:10:24 -0400 MIME-Version: 1.0 In-Reply-To: <5AAF838D.2030105@broadcom.com> References: <20180319014032.9394-1-alexey.roslyakov@gmail.com> <20180319014032.9394-3-alexey.roslyakov@gmail.com> <5AAF838D.2030105@broadcom.com> From: Alexey Roslyakov Date: Mon, 19 Mar 2018 21:10:21 +0700 Message-ID: (sfid-20180319_151048_184221_47892B55) Subject: Re: [PATCH net-next v2 2/2] dt: bindings: add new dt entries for brcmfmac To: Arend van Spriel Cc: Andrew Lunn , kvalo@codeaurora.org, robh+dt@kernel.org, mark.rutland@arm.com, franky.lin@broadcom.com, hante.meuleman@broadcom.com, chi-hsien.lin@cypress.com, wright.feng@cypress.com, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, brcm80211-dev-list.pdl@broadcom.com, brcm80211-dev-list@cypress.com Content-Type: text/plain; charset="UTF-8" Sender: linux-wireless-owner@vger.kernel.org List-ID: Hi Arend, I appreciate your response. In my opinion, it has nothing to do with SDIO host, because it defines "quirks" in the driver itself. If I get it right, you mean something like this: mmc3: mmc@1c12000 { ... broken-sg-support; sd-head-align = 4; sd-sgentry-align = 512; brcmf: wifi@1 { ... }; }; Where dt: bindings documentation for these entries should reside? In generic MMC bindings? Well, this is the very special case and mmc-linux maintainer will unlikely to accept these changes. Also, extra kernel code modification might be required. It could make quite trivial change much more complex. >Also I am not sure if the broken-sg-support is still needed. We added that for omap_hsmmc, but that has since changed to scatter-gather emulation so it might not be needed anymore. I've experienced the problem with rk3288 (dw-mmc host) and sdio settings like above solved it. Frankly, I haven't investigated any deeper which one of the settings helped in my case yet... I will try to get rid of broken-sg-support first and let you know if it does make any difference. All the best, Alex. On 19 March 2018 at 16:31, Arend van Spriel wrote: > On 3/19/2018 2:40 AM, Alexey Roslyakov wrote: >> >> In case if the host has higher align requirements for SG items, allow >> setting device-specific aligns for scatterlist items. >> >> Signed-off-by: Alexey Roslyakov >> --- >> Documentation/devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt | 5 >> +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git >> a/Documentation/devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt >> b/Documentation/devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt >> index 86602f264dce..187b8c1b52a7 100644 >> --- a/Documentation/devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt >> +++ b/Documentation/devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt >> @@ -17,6 +17,11 @@ Optional properties: >> When not specified the device will use in-band SDIO interrupts. >> - interrupt-names : name of the out-of-band interrupt, which must be >> set >> to "host-wake". >> + - brcm,broken-sg-support : boolean flag to indicate that the SDIO host >> + controller has higher align requirement than 32 bytes for each >> + scatterlist item. >> + - brcm,sd-head-align : alignment requirement for start of data buffer. >> + - brcm,sd-sgentry-align : length alignment requirement for each sg >> entry. > > > Hi Alexey, > > Thanks for the patch. However, the problem with these is that they are > characterizing the host controller and not the wireless device. So from > device tree perspective , which is to describe the hardware, these > properties should be SDIO host controller properties. Also I am not sure if > the broken-sg-support is still needed. We added that for omap_hsmmc, but > that has since changed to scatter-gather emulation so it might not be needed > anymore. > > Regards, > Arend -- With best regards, Alexey Roslyakov Email: alexey.roslyakov@gmail.com