From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ilya Yanok Date: Thu, 28 Jun 2012 17:57:53 +0400 Subject: [U-Boot] [PATCH v4 3/6] mcx: Disable DCACHE since USB EHCI is enabled In-Reply-To: <201206280048.15039.marex@denx.de> References: <1340209283-3404-1-git-send-email-trini@ti.com> <1340230468-12811-4-git-send-email-trini@ti.com> <4FEB890D.3010801@emcraft.com> <201206280048.15039.marex@denx.de> Message-ID: <4FEC62E1.3030002@emcraft.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Dear Marek, 28.06.2012 02:48, Marek Vasut wrote: >> Sorry for missing this discussion. I think compile-time disabling of the >> cache is too brutal. >> ehci-hcd cache handling is broken anyway: doing unaligned >> flushes/invalidates is a bug, and we know for sure that upper layers >> don't care about alignment (and I bet ehci-hcd does this even for its >> internal buffers). So what's the point in all this cache handling in >> ehci-hcd? It's not going to work anyway and just produces problems. So I >> suggest to just disable all this stuff until generic code will be fixed. >> Alternatively we can do bounce-buffering inside driver. > We should rather introduce generic bounce buffer. But the upper layers are > getting fixed recently so we should be getting there. Really? Don't forget my old patch [1] then ;) Still I think we should rip off all the cache stuff from ehci-hcd until all patches for upper layers are included. Again, this stuff doesn't do proper things now anyway and USB won't work with dcache enabled. BTW, I think this was under #ifdef CONFIG_EHCI_DCACHE last time looked at it. Was this changed by your commit? I think that's the source of the problem this series tries to address: you've taken buggy code out of #ifdef ;) I think it's better to just put it back until upper layers won't be fixed. Regards, Ilya. [1] http://thread.gmane.org/gmane.comp.boot-loaders.u-boot/114235