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authorVineet Gupta <vgupta@synopsys.com>2016-12-19 11:38:38 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-01-09 08:07:48 +0100
commit429a533a3d9ac849b4c9c3ceed14aa4282301748 (patch)
tree0937dd85638126e9a0cf33829dd4b6110bf7be08 /arch/arc
parentdbb67e1d585d81a720fa75cee767e49dc4a50164 (diff)
ARC: mm: arc700: Don't assume 2 colours for aliasing VIPT dcache
commit 08fe007968b2b45e831daf74899f79a54d73f773 upstream. An ARC700 customer reported linux boot crashes when upgrading to bigger L1 dcache (64K from 32K). Turns out they had an aliasing VIPT config and current code only assumed 2 colours, while theirs had 4. So default to 4 colours and complain if there are fewer. Ideally this needs to be a Kconfig option, but heck that's too much of hassle for a single user. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arc')
-rw-r--r--arch/arc/include/asm/cacheflush.h6
-rw-r--r--arch/arc/mm/cache.c13
2 files changed, 13 insertions, 6 deletions
diff --git a/arch/arc/include/asm/cacheflush.h b/arch/arc/include/asm/cacheflush.h
index fbe3587c4f36..56aeb5efe604 100644
--- a/arch/arc/include/asm/cacheflush.h
+++ b/arch/arc/include/asm/cacheflush.h
@@ -85,6 +85,10 @@ void flush_anon_page(struct vm_area_struct *vma,
*/
#define PG_dc_clean PG_arch_1
+#define CACHE_COLORS_NUM 4
+#define CACHE_COLORS_MSK (CACHE_COLORS_NUM - 1)
+#define CACHE_COLOR(addr) (((unsigned long)(addr) >> (PAGE_SHIFT)) & CACHE_COLORS_MSK)
+
/*
* Simple wrapper over config option
* Bootup code ensures that hardware matches kernel configuration
@@ -94,8 +98,6 @@ static inline int cache_is_vipt_aliasing(void)
return IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING);
}
-#define CACHE_COLOR(addr) (((unsigned long)(addr) >> (PAGE_SHIFT)) & 1)
-
/*
* checks if two addresses (after page aligning) index into same cache set
*/
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index aaf1e2d1d900..d81b6d7e11e7 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -960,11 +960,16 @@ void arc_cache_init(void)
/* check for D-Cache aliasing on ARCompact: ARCv2 has PIPT */
if (is_isa_arcompact()) {
int handled = IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING);
-
- if (dc->alias && !handled)
- panic("Enable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
- else if (!dc->alias && handled)
+ int num_colors = dc->sz_k/dc->assoc/TO_KB(PAGE_SIZE);
+
+ if (dc->alias) {
+ if (!handled)
+ panic("Enable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
+ if (CACHE_COLORS_NUM != num_colors)
+ panic("CACHE_COLORS_NUM not optimized for config\n");
+ } else if (!dc->alias && handled) {
panic("Disable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
+ }
}
}