From: Marek Vasut Date: Sat, 17 Oct 2015 02:15:12 +0200 Subject: [U-Boot] [PATCHv2] arm: socfpga: enable data/inst prefetch and shared override in the L2 In-Reply-To: <1444922016-3501-1-git-send-email-dinguyen@opensource.altera.com> References: <1444922016-3501-1-git-send-email-dinguyen@opensource.altera.com> Message-ID: <201510170215.12369.marex@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Thursday, October 15, 2015 at 05:13:36 PM, dinguyen at opensource.altera.com wrote: > From: Dinh Nguyen > > Update the L2 AUX CTRL settings for the SoCFPGA. > > Enabling D and I prefetch bits helps improve SDRAM performance on the > platform. > > Also, we need to enable bit 22 of the L2. By not having bit 22 set in the > PL310 Auxiliary Control register (shared attribute override enable) has the > side effect of transforming Normal Shared Non-cacheable reads into > Cacheable no-allocate reads. > > Coherent DMA buffers in Linux always have a Cacheable alias via the > kernel linear mapping and the processor can speculatively load cache > lines into the PL310 controller. With bit 22 cleared, Non-cacheable > reads would unexpectedly hit such cache lines leading to buffer > corruption. > > Signed-off-by: Dinh Nguyen Applied, thanks! Best regards, Marek Vasut