Hi Stefan, On 17/09/2018 12:39, Stefan Wahren wrote: > Hi Phil, > > Am 17.09.2018 um 10:22 schrieb Phil Elwell: >> Both sides of the VCHIQ communications mechanism need to agree on the cache >> line size. Using an incorrect value can lead to data corruption, but having the >> two sides using different values is usually worse. >> >> In the absence of an obvious convenient run-time method to determine the >> correct value in the ARCH=arm world, the downstream Raspberry Pi trees used a >> Device Tree property, written by the firmware, to configure the kernel driver. >> This method was vetoed during the upstreaming process, so a fixed value of 32 >> was used instead, and some corruptions ensued. This is take 2 at arriving at >> the correct value. >> >> Add a new compatible string - "brcm,bcm2836-vchiq" - to indicate an SoC with >> a 64-byte cache line. Document the new string in the binding, and use it on >> the appropriate platforms. >> >> The final patch is a (seemingly cosmetic) correction of the Device Tree "reg" >> declaration for the device node, but it doubles as an indication to the >> Raspberry Pi firmware that the kernel driver is running a recent kernel driver >> that chooses the correct value. As such it would help if the DT patches are >> not merged before the driver patch. >> >> v3: Builds without errors, tested on multiple Raspberry Pi models. >> v2: Replaced ARM-specific logic used to determine cache line size with >> a new compatible string for BCM2836 and BCM2837. >> >> Phil Elwell (4): >> staging/vc04_services: Use correct cache line size >> dt-bindings: soc: Document "brcm,bcm2836-vchiq" >> ARM: dts: bcm283x: Correct vchiq compatible string >> ARM: dts: bcm283x: Correct mailbox register sizes > > since my pull requests are out, would it be okay to apply patch #1 for > 4.20 and the DT stuff for 4.21 (with the assumption Rob is okay with > these patches)? Patch 4 is the only one I'd like to be delayed, but delaying 2-4 is fine with me. Phil _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
