From: Per Larsen <perlarsen@google.com>
The minimum size and alignment boundary for FFA_RXTX_MAP is returned in
bit[1:0]. Mask off any other bits in w2 when reading the minimum buffer
size in hyp_ffa_post_init.
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Per Larsen <perlarsen@google.com>
---
arch/arm64/kvm/hyp/nvhe/ffa.c | 2 +-
include/linux/arm_ffa.h | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c
index bcb2fab66a61190733682c5bda44e2fa6766177a..22a369f8d1d8edcde45d77377e29dc08256c0bcc 100644
--- a/arch/arm64/kvm/hyp/nvhe/ffa.c
+++ b/arch/arm64/kvm/hyp/nvhe/ffa.c
@@ -734,7 +734,7 @@ static int hyp_ffa_post_init(void)
if (res.a0 != FFA_SUCCESS)
return -EOPNOTSUPP;
- switch (res.a2) {
+ switch (res.a2 & FFA_FEAT_RXTX_MIN_SZ_MASK) {
case FFA_FEAT_RXTX_MIN_SZ_4K:
min_rxtx_sz = SZ_4K;
break;
diff --git a/include/linux/arm_ffa.h b/include/linux/arm_ffa.h
index e1634897e159cdc208931938649eb0fb04d5a070..cd7ee4df9045dceca1c4e0dca2d533b770b1b056 100644
--- a/include/linux/arm_ffa.h
+++ b/include/linux/arm_ffa.h
@@ -128,6 +128,7 @@
#define FFA_FEAT_RXTX_MIN_SZ_4K 0
#define FFA_FEAT_RXTX_MIN_SZ_64K 1
#define FFA_FEAT_RXTX_MIN_SZ_16K 2
+#define FFA_FEAT_RXTX_MIN_SZ_MASK GENMASK(1, 0)
/* FFA Bus/Device/Driver related */
struct ffa_device {
--
2.51.0.rc0.155.g4a0f42376b-goog