[PATCH v3 2/3] arm64: tlb: Improve __TLBI_VADDR_RANGE()

From: Gavin Shan
Date: Thu Apr 04 2024 - 23:59:54 EST


The macro returns the operand of TLBI RANGE instruction. A mask needs
to be applied to each individual field upon producing the operand, to
avoid the adjacent fields can interfere with each other when invalid
arguments have been provided. The code looks more tidy at least with
a mask and FIELD_PREP().

Suggested-by: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Gavin Shan <gshan@xxxxxxxxxx>
---
arch/arm64/include/asm/tlbflush.h | 29 ++++++++++++++++++-----------
1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index a75de2665d84..243d71f7bc1f 100644
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -142,17 +142,24 @@ static inline unsigned long get_trans_granule(void)
* EL1, Inner Shareable".
*
*/
-#define __TLBI_VADDR_RANGE(baddr, asid, scale, num, ttl) \
- ({ \
- unsigned long __ta = (baddr); \
- unsigned long __ttl = (ttl >= 1 && ttl <= 3) ? ttl : 0; \
- __ta &= GENMASK_ULL(36, 0); \
- __ta |= __ttl << 37; \
- __ta |= (unsigned long)(num) << 39; \
- __ta |= (unsigned long)(scale) << 44; \
- __ta |= get_trans_granule() << 46; \
- __ta |= (unsigned long)(asid) << 48; \
- __ta; \
+#define TLBIR_ASID_MASK GENMASK_ULL(63, 48)
+#define TLBIR_TG_MASK GENMASK_ULL(47, 46)
+#define TLBIR_SCALE_MASK GENMASK_ULL(45, 44)
+#define TLBIR_NUM_MASK GENMASK_ULL(43, 39)
+#define TLBIR_TTL_MASK GENMASK_ULL(38, 37)
+#define TLBIR_BADDR_MASK GENMASK_ULL(36, 0)
+
+#define __TLBI_VADDR_RANGE(baddr, asid, scale, num, ttl) \
+ ({ \
+ unsigned long __ta = 0; \
+ unsigned long __ttl = (ttl >= 1 && ttl <= 3) ? ttl : 0; \
+ __ta |= FIELD_PREP(TLBIR_BADDR_MASK, baddr); \
+ __ta |= FIELD_PREP(TLBIR_TTL_MASK, __ttl); \
+ __ta |= FIELD_PREP(TLBIR_NUM_MASK, num); \
+ __ta |= FIELD_PREP(TLBIR_SCALE_MASK, scale); \
+ __ta |= FIELD_PREP(TLBIR_TG_MASK, get_trans_granule()); \
+ __ta |= FIELD_PREP(TLBIR_ASID_MASK, asid); \
+ __ta; \
})

/* These macros are used by the TLBI RANGE feature. */
--
2.44.0