[PATCH AUTOSEL 4.19 52/73] ARM: 8815/1: V7M: align v7m_dma_inv_range() with v7 counterpart

From: Sasha Levin
Date: Wed Dec 12 2018 - 23:47:15 EST


From: Vladimir Murzin <vladimir.murzin@xxxxxxx>

[ Upstream commit 3d0358d0ba048c5afb1385787aaec8fa5ad78fcc ]

Chris has discovered and reported that v7_dma_inv_range() may corrupt
memory if address range is not aligned to cache line size.

Since the whole cache-v7m.S was lifted form cache-v7.S the same
observation applies to v7m_dma_inv_range(). So the fix just mirrors
what has been done for v7 with a little specific of M-class.

Cc: Chris Cole <chris@xxxxxxxxxxxxxxxx>
Signed-off-by: Vladimir Murzin <vladimir.murzin@xxxxxxx>
Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm/mm/cache-v7m.S | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mm/cache-v7m.S b/arch/arm/mm/cache-v7m.S
index 788486e830d3..32aa2a2aa260 100644
--- a/arch/arm/mm/cache-v7m.S
+++ b/arch/arm/mm/cache-v7m.S
@@ -73,9 +73,11 @@
/*
* dcimvac: Invalidate data cache line by MVA to PoC
*/
-.macro dcimvac, rt, tmp
- v7m_cacheop \rt, \tmp, V7M_SCB_DCIMVAC
+.irp c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo
+.macro dcimvac\c, rt, tmp
+ v7m_cacheop \rt, \tmp, V7M_SCB_DCIMVAC, \c
.endm
+.endr

/*
* dccmvau: Clean data cache line by MVA to PoU
@@ -369,14 +371,16 @@ v7m_dma_inv_range:
tst r0, r3
bic r0, r0, r3
dccimvacne r0, r3
+ addne r0, r0, r2
subne r3, r2, #1 @ restore r3, corrupted by v7m's dccimvac
tst r1, r3
bic r1, r1, r3
dccimvacne r1, r3
-1:
- dcimvac r0, r3
- add r0, r0, r2
cmp r0, r1
+1:
+ dcimvaclo r0, r3
+ addlo r0, r0, r2
+ cmplo r0, r1
blo 1b
dsb st
ret lr
--
2.19.1