From ff1c0b6a795bce744527bc10c8268127ed818b42 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Tue, 15 Dec 2015 13:57:16 +0530 Subject: [PATCH] ARC: [plat-sim] unbork non default CONFIG_LINUX_LINK_BASE HIGHMEM support bumped the default memory size for nsim platform to 1G. Thus total memory ended at the very edge of start of peripherals address space. With linux link base shifted, memory started bleeding into peripheral space which caused early boot bad_page spew ! Fixes: 29e332261d2 ("ARC: mm: HIGHMEM: populate high memory from DT") Reported-by: Anton Kolesov Signed-off-by: Vineet Gupta --- arch/arc/Kconfig | 1 + arch/arc/boot/dts/nsim_hs.dts | 3 ++- arch/arc/mm/init.c | 4 +++- 3 files changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 2c2ac3f3ff80..6312f607932f 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -445,6 +445,7 @@ config LINUX_LINK_BASE However some customers have peripherals mapped at this addr, so Linux needs to be scooted a bit. If you don't know what the above means, leave this setting alone. + This needs to match memory start address specified in Device Tree config HIGHMEM bool "High Memory Support" diff --git a/arch/arc/boot/dts/nsim_hs.dts b/arch/arc/boot/dts/nsim_hs.dts index b0eb0e7fe21d..fc81879bc1f5 100644 --- a/arch/arc/boot/dts/nsim_hs.dts +++ b/arch/arc/boot/dts/nsim_hs.dts @@ -17,7 +17,8 @@ memory { device_type = "memory"; - reg = <0x0 0x80000000 0x0 0x40000000 /* 1 GB low mem */ + /* CONFIG_LINUX_LINK_BASE needs to match low mem start */ + reg = <0x0 0x80000000 0x0 0x20000000 /* 512 MB low mem */ 0x1 0x00000000 0x0 0x40000000>; /* 1 GB highmem */ }; diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c index a9305b5a2cd4..7d2c4fbf4f22 100644 --- a/arch/arc/mm/init.c +++ b/arch/arc/mm/init.c @@ -51,7 +51,9 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size) int in_use = 0; if (!low_mem_sz) { - BUG_ON(base != low_mem_start); + if (base != low_mem_start) + panic("CONFIG_LINUX_LINK_BASE != DT memory { }"); + low_mem_sz = size; in_use = 1; } else { -- 2.20.1