From 1348e3b71337ea8c30b485e6a9e9c6acfebbe809 Mon Sep 17 00:00:00 2001 From: Mikko Perttunen Date: Mon, 22 May 2023 15:36:45 +0300 Subject: [PATCH] UPSTREAM: arm64: tegra: Mark BPMP channels as no-memory-wc The Tegra SYSRAM contains regions access to which is restricted to certain hardware blocks on the system, and speculative accesses to those will cause issues. Patch 'misc: sram: Only map reserved areas in Tegra SYSRAM' attempted to resolve this by only mapping the regions specified in the device tree on the assumption that there are no such restricted areas within the 64K-aligned area of memory that contains the memory we wish to map. Turns out this assumption is wrong, as there are such areas above the 4K pages described in the device trees. As such, we need to use the bigger hammer that is no-memory-wc, which causes the memory to be mapped as Device memory to which speculative accesses are disallowed. As such, the previous patch in the series, 'firmware: tegra: bpmp: do only aligned access to IPC memory area', is required with this patch to make the BPMP driver only issue aligned memory accesses as those are also required with Device memory. Fixes: fec29bf04994 ("misc: sram: Only map reserved areas in Tegra SYSRAM") Signed-off-by: Mikko Perttunen Reviewed-by: Yousaf Kaukab Signed-off-by: Thierry Reding [mperttunen@nvidia.com: port to downstream dts] Signed-off-by: Mikko Perttunen Change-Id: I8a864a5a858077a1f1d2d45da706559637bc3a94 Reviewed-on: https://git-master.nvidia.com/r/c/device/hardware/nvidia/t23x-public-dts/+/2908381 Reviewed-by: svcacv Reviewed-by: Laxman Dewangan GVS: Gerrit_Virtual_Submit Tested-by: Bitan Biswas --- tegra234.dtsi | 1 + 1 file changed, 1 insertion(+) diff --git a/tegra234.dtsi b/tegra234.dtsi index e977606..480bae6 100644 --- a/tegra234.dtsi +++ b/tegra234.dtsi @@ -2963,6 +2963,7 @@ #address-cells = <1>; #size-cells = <1>; ranges = <0x0 0x0 0x40000000 0x80000>; + no-memory-wc; cpu_bpmp_tx: sram@70000 { reg = <0x70000 0x1000>;