[net v2 PATCH] octeontx2-pf: Avoid typecasts by simplifying otx2_atomic64_add macro

[net v2 PATCH] octeontx2-pf: Avoid typecasts by simplifying otx2_atomic64_add macro

[Subbaraya Sundeep]

Just because otx2_atomic64_add is using u64 pointer as argument
all callers has to typecast __iomem void pointers which inturn
causing sparse warnings. Fix those by changing otx2_atomic64_add
argument to void pointer.

Fixes: caa2da34fd25 ("octeontx2-pf: Initialize and config queues")
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
---
v2:
 Fixed x86 build error of void pointer dereference reported by
 kernel test robot

 .../net/ethernet/marvell/octeontx2/nic/otx2_common.c    | 17 +++++++++--------
 .../net/ethernet/marvell/octeontx2/nic/otx2_common.h    |  7 ++++---
 drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c    |  4 ++--
 drivers/net/ethernet/marvell/octeontx2/nic/qos_sq.c     |  5 +++--
 4 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
index 84cd029..e5be021 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
@@ -28,12 +28,12 @@ static void otx2_nix_rq_op_stats(struct queue_stats *stats,
 				 struct otx2_nic *pfvf, int qidx)
 {
 	u64 incr = (u64)qidx << 32;
-	u64 *ptr;
+	void __iomem *ptr;
 
-	ptr = (u64 *)otx2_get_regaddr(pfvf, NIX_LF_RQ_OP_OCTS);
+	ptr = otx2_get_regaddr(pfvf, NIX_LF_RQ_OP_OCTS);
 	stats->bytes = otx2_atomic64_add(incr, ptr);
 
-	ptr = (u64 *)otx2_get_regaddr(pfvf, NIX_LF_RQ_OP_PKTS);
+	ptr = otx2_get_regaddr(pfvf, NIX_LF_RQ_OP_PKTS);
 	stats->pkts = otx2_atomic64_add(incr, ptr);
 }
 
@@ -41,12 +41,12 @@ static void otx2_nix_sq_op_stats(struct queue_stats *stats,
 				 struct otx2_nic *pfvf, int qidx)
 {
 	u64 incr = (u64)qidx << 32;
-	u64 *ptr;
+	void __iomem *ptr;
 
-	ptr = (u64 *)otx2_get_regaddr(pfvf, NIX_LF_SQ_OP_OCTS);
+	ptr = otx2_get_regaddr(pfvf, NIX_LF_SQ_OP_OCTS);
 	stats->bytes = otx2_atomic64_add(incr, ptr);
 
-	ptr = (u64 *)otx2_get_regaddr(pfvf, NIX_LF_SQ_OP_PKTS);
+	ptr = otx2_get_regaddr(pfvf, NIX_LF_SQ_OP_PKTS);
 	stats->pkts = otx2_atomic64_add(incr, ptr);
 }
 
@@ -860,9 +860,10 @@ void otx2_sqb_flush(struct otx2_nic *pfvf)
 {
 	int qidx, sqe_tail, sqe_head;
 	struct otx2_snd_queue *sq;
-	u64 incr, *ptr, val;
+	void __iomem *ptr;
+	u64 incr, val;
 
-	ptr = (u64 *)otx2_get_regaddr(pfvf, NIX_LF_SQ_OP_STATUS);
+	ptr = otx2_get_regaddr(pfvf, NIX_LF_SQ_OP_STATUS);
 	for (qidx = 0; qidx < otx2_get_total_tx_queues(pfvf); qidx++) {
 		sq = &pfvf->qset.sq[qidx];
 		if (!sq->sqb_ptrs)
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
index d6b4b74..7058c8b 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.h
@@ -733,8 +733,9 @@ static inline void otx2_write128(u64 lo, u64 hi, void __iomem *addr)
 			 ::[x0]"r"(lo), [x1]"r"(hi), [p1]"r"(addr));
 }
 
-static inline u64 otx2_atomic64_add(u64 incr, u64 *ptr)
+static inline u64 otx2_atomic64_add(u64 incr, void __iomem *addr)
 {
+	u64 __iomem *ptr = addr;
 	u64 result;
 
 	__asm__ volatile(".cpu   generic+lse\n"
@@ -747,7 +748,7 @@ static inline u64 otx2_atomic64_add(u64 incr, u64 *ptr)
 
 #else
 #define otx2_write128(lo, hi, addr)		writeq((hi) | (lo), addr)
-#define otx2_atomic64_add(incr, ptr)		({ *ptr += incr; })
+#define otx2_atomic64_add(incr, ptr)		({ *((u64 *)ptr) += incr; })
 #endif
 
 static inline void __cn10k_aura_freeptr(struct otx2_nic *pfvf, u64 aura,
@@ -797,7 +798,7 @@ static inline void cn10k_aura_freeptr(void *dev, int aura, u64 buf)
 /* Alloc pointer from pool/aura */
 static inline u64 otx2_aura_allocptr(struct otx2_nic *pfvf, int aura)
 {
-	u64 *ptr = (__force u64 *)otx2_get_regaddr(pfvf, NPA_LF_AURA_OP_ALLOCX(0));
+	void __iomem *ptr = otx2_get_regaddr(pfvf, NPA_LF_AURA_OP_ALLOCX(0));
 	u64 incr = (u64)aura | BIT_ULL(63);
 
 	return otx2_atomic64_add(incr, ptr);
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
index cfed9ec..b303a03 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
@@ -1305,8 +1305,8 @@ static irqreturn_t otx2_q_intr_handler(int irq, void *data)
 {
 	struct otx2_nic *pf = data;
 	struct otx2_snd_queue *sq;
-	u64 val, *ptr;
-	u64 qidx = 0;
+	void __iomem *ptr;
+	u64 val, qidx = 0;
 
 	/* CQ */
 	for (qidx = 0; qidx < pf->qset.cq_cnt; qidx++) {
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/qos_sq.c b/drivers/net/ethernet/marvell/octeontx2/nic/qos_sq.c
index c5dbae0..d3ae390 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/qos_sq.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/qos_sq.c
@@ -151,9 +151,10 @@ static void otx2_qos_sq_free_sqbs(struct otx2_nic *pfvf, int qidx)
 static void otx2_qos_sqb_flush(struct otx2_nic *pfvf, int qidx)
 {
 	int sqe_tail, sqe_head;
-	u64 incr, *ptr, val;
+	void __iomem *ptr;
+	u64 incr, val;
 
-	ptr = (__force u64 *)otx2_get_regaddr(pfvf, NIX_LF_SQ_OP_STATUS);
+	ptr = otx2_get_regaddr(pfvf, NIX_LF_SQ_OP_STATUS);
 	incr = (u64)qidx << 32;
 	val = otx2_atomic64_add(incr, ptr);
 	sqe_head = (val >> 20) & 0x3F;
-- 
2.7.4

Re: [net v2 PATCH] octeontx2-pf: Avoid typecasts by simplifying otx2_atomic64_add macro

[Simon Horman]

On Tue, May 27, 2025 at 03:33:00PM +0530, Subbaraya Sundeep wrote:
> Just because otx2_atomic64_add is using u64 pointer as argument
> all callers has to typecast __iomem void pointers which inturn
> causing sparse warnings. Fix those by changing otx2_atomic64_add
> argument to void pointer.

I'm wondering if you considered changing the type of the 2nd parameter
of otx2_atomic64_add to u64 __iomem * and, correspondingly, the type
of the local variables updated by this patch. Perhaps that isn't so
clean for some reason. But if it can be done cleanly it does seem slightly
nicer to me.

> 
> Fixes: caa2da34fd25 ("octeontx2-pf: Initialize and config queues")

I do appreciate this change. But I wonder if it is more of a
clean-up for net-next (once it re-opens, no Fixes tag) than
a fix.

> Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
> ---
> v2:
>  Fixed x86 build error of void pointer dereference reported by
>  kernel test robot

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