[PATCH v2 0/2] net: mvpp2: driver fixes

[PATCH v2 0/2] net: mvpp2: driver fixes

[Thomas Petazzoni]

Hello,

As requested, here is a series of patches containing only bug fixes
for the mvpp2 driver. It is based on the latest "net" branch.

Changes since v1:

 - Fixed a build breakage that occurred when only PATCH 1 was only,
   and not later patches in the series. Was reported by the kbuild
   report on the first submission.

 - Added Tested-by from Marc Zyngier on PATCH 2.

Thanks!

Thomas

Thomas Petazzoni (2):
  net: mvpp2: remove mvpp2_bm_cookie_{build,pool_get}
  net: mvpp2: use {get,put}_cpu() instead of smp_processor_id()

 drivers/net/ethernet/marvell/mvpp2.c | 74 ++++++++++++++++--------------------
 1 file changed, 33 insertions(+), 41 deletions(-)

-- 
2.9.4

[PATCH v2 1/2] net: mvpp2: remove mvpp2_bm_cookie_{build,pool_get}

[Thomas Petazzoni]

This commit removes the useless remove
mvpp2_bm_cookie_{build,pool_get} functions. All what
mvpp2_bm_cookie_build() was doing is compute a 32-bit value by
concatenating the pool number and the CPU number... only to get the pool
number re-extracted by mvpp2_bm_cookie_pool_get() later on.

Instead, just get the pool number directly from RX descriptor status,
and pass it to mvpp2_pool_refill() and mvpp2_rx_refill().

This has the added benefit of dropping a smp_processor_id() call in a
migration-enabled context, which is wrong, and is the original
motivation for making this change.

Fixes: 3f518509dedc9 ("ethernet: Add new driver for Marvell Armada 375 network unit")
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 drivers/net/ethernet/marvell/mvpp2.c | 47 +++++++++++-------------------------
 1 file changed, 14 insertions(+), 33 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c
index 70bca2a..5841e53 100644
--- a/drivers/net/ethernet/marvell/mvpp2.c
+++ b/drivers/net/ethernet/marvell/mvpp2.c
@@ -3920,12 +3920,6 @@ static inline u32 mvpp2_bm_cookie_pool_set(u32 cookie, int pool)
 	return bm;
 }
 
-/* Get pool number from a BM cookie */
-static inline int mvpp2_bm_cookie_pool_get(unsigned long cookie)
-{
-	return (cookie >> MVPP2_BM_COOKIE_POOL_OFFS) & 0xFF;
-}
-
 /* Release buffer to BM */
 static inline void mvpp2_bm_pool_put(struct mvpp2_port *port, int pool,
 				     dma_addr_t buf_dma_addr,
@@ -3961,12 +3955,10 @@ static inline void mvpp2_bm_pool_put(struct mvpp2_port *port, int pool,
 }
 
 /* Refill BM pool */
-static void mvpp2_pool_refill(struct mvpp2_port *port, u32 bm,
+static void mvpp2_pool_refill(struct mvpp2_port *port, int pool,
 			      dma_addr_t dma_addr,
 			      phys_addr_t phys_addr)
 {
-	int pool = mvpp2_bm_cookie_pool_get(bm);
-
 	mvpp2_bm_pool_put(port, pool, dma_addr, phys_addr);
 }
 
@@ -4513,21 +4505,6 @@ static void mvpp2_rxq_offset_set(struct mvpp2_port *port,
 	mvpp2_write(port->priv, MVPP2_RXQ_CONFIG_REG(prxq), val);
 }
 
-/* Obtain BM cookie information from descriptor */
-static u32 mvpp2_bm_cookie_build(struct mvpp2_port *port,
-				 struct mvpp2_rx_desc *rx_desc)
-{
-	int cpu = smp_processor_id();
-	int pool;
-
-	pool = (mvpp2_rxdesc_status_get(port, rx_desc) &
-		MVPP2_RXD_BM_POOL_ID_MASK) >>
-		MVPP2_RXD_BM_POOL_ID_OFFS;
-
-	return ((pool & 0xFF) << MVPP2_BM_COOKIE_POOL_OFFS) |
-	       ((cpu & 0xFF) << MVPP2_BM_COOKIE_CPU_OFFS);
-}
-
 /* Tx descriptors helper methods */
 
 /* Get pointer to next Tx descriptor to be processed (send) by HW */
@@ -4978,9 +4955,13 @@ static void mvpp2_rxq_drop_pkts(struct mvpp2_port *port,
 
 	for (i = 0; i < rx_received; i++) {
 		struct mvpp2_rx_desc *rx_desc = mvpp2_rxq_next_desc_get(rxq);
-		u32 bm = mvpp2_bm_cookie_build(port, rx_desc);
+		u32 status = mvpp2_rxdesc_status_get(port, rx_desc);
+		int pool;
+
+		pool = (status & MVPP2_RXD_BM_POOL_ID_MASK) >>
+			MVPP2_RXD_BM_POOL_ID_OFFS;
 
-		mvpp2_pool_refill(port, bm,
+		mvpp2_pool_refill(port, pool,
 				  mvpp2_rxdesc_dma_addr_get(port, rx_desc),
 				  mvpp2_rxdesc_cookie_get(port, rx_desc));
 	}
@@ -5418,7 +5399,7 @@ static void mvpp2_rx_csum(struct mvpp2_port *port, u32 status,
 
 /* Reuse skb if possible, or allocate a new skb and add it to BM pool */
 static int mvpp2_rx_refill(struct mvpp2_port *port,
-			   struct mvpp2_bm_pool *bm_pool, u32 bm)
+			   struct mvpp2_bm_pool *bm_pool, int pool)
 {
 	dma_addr_t dma_addr;
 	phys_addr_t phys_addr;
@@ -5430,7 +5411,7 @@ static int mvpp2_rx_refill(struct mvpp2_port *port,
 	if (!buf)
 		return -ENOMEM;
 
-	mvpp2_pool_refill(port, bm, dma_addr, phys_addr);
+	mvpp2_pool_refill(port, pool, dma_addr, phys_addr);
 
 	return 0;
 }
@@ -5488,7 +5469,7 @@ static int mvpp2_rx(struct mvpp2_port *port, int rx_todo,
 		unsigned int frag_size;
 		dma_addr_t dma_addr;
 		phys_addr_t phys_addr;
-		u32 bm, rx_status;
+		u32 rx_status;
 		int pool, rx_bytes, err;
 		void *data;
 
@@ -5500,8 +5481,8 @@ static int mvpp2_rx(struct mvpp2_port *port, int rx_todo,
 		phys_addr = mvpp2_rxdesc_cookie_get(port, rx_desc);
 		data = (void *)phys_to_virt(phys_addr);
 
-		bm = mvpp2_bm_cookie_build(port, rx_desc);
-		pool = mvpp2_bm_cookie_pool_get(bm);
+		pool = (rx_status & MVPP2_RXD_BM_POOL_ID_MASK) >>
+			MVPP2_RXD_BM_POOL_ID_OFFS;
 		bm_pool = &port->priv->bm_pools[pool];
 
 		/* In case of an error, release the requested buffer pointer
@@ -5514,7 +5495,7 @@ static int mvpp2_rx(struct mvpp2_port *port, int rx_todo,
 			dev->stats.rx_errors++;
 			mvpp2_rx_error(port, rx_desc);
 			/* Return the buffer to the pool */
-			mvpp2_pool_refill(port, bm, dma_addr, phys_addr);
+			mvpp2_pool_refill(port, pool, dma_addr, phys_addr);
 			continue;
 		}
 
@@ -5529,7 +5510,7 @@ static int mvpp2_rx(struct mvpp2_port *port, int rx_todo,
 			goto err_drop_frame;
 		}
 
-		err = mvpp2_rx_refill(port, bm_pool, bm);
+		err = mvpp2_rx_refill(port, bm_pool, pool);
 		if (err) {
 			netdev_err(port->dev, "failed to refill BM pools\n");
 			goto err_drop_frame;
-- 
2.9.4

[PATCH v2 2/2] net: mvpp2: use {get,put}_cpu() instead of smp_processor_id()

[Thomas Petazzoni]

smp_processor_id() should not be used in migration-enabled contexts. We
originally thought it was OK in the specific situation of this driver,
but it was wrong, and calling smp_processor_id() in a migration-enabled
context prints a big fat warning when CONFIG_DEBUG_PREEMPT=y.

Therefore, this commit replaces the smp_processor_id() in
migration-enabled contexts by the appropriate get_cpu/put_cpu sections.

Reported-by: Marc Zyngier <marc.zyngier@arm.com>
Fixes: a786841df72e ("net: mvpp2: handle register mapping and access for PPv2.2")
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
---
 drivers/net/ethernet/marvell/mvpp2.c | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c
index 5841e53..33c9016 100644
--- a/drivers/net/ethernet/marvell/mvpp2.c
+++ b/drivers/net/ethernet/marvell/mvpp2.c
@@ -3719,7 +3719,7 @@ static void mvpp2_bm_bufs_get_addrs(struct device *dev, struct mvpp2 *priv,
 				    dma_addr_t *dma_addr,
 				    phys_addr_t *phys_addr)
 {
-	int cpu = smp_processor_id();
+	int cpu = get_cpu();
 
 	*dma_addr = mvpp2_percpu_read(priv, cpu,
 				      MVPP2_BM_PHY_ALLOC_REG(bm_pool->id));
@@ -3740,6 +3740,8 @@ static void mvpp2_bm_bufs_get_addrs(struct device *dev, struct mvpp2 *priv,
 		if (sizeof(phys_addr_t) == 8)
 			*phys_addr |= (u64)phys_addr_highbits << 32;
 	}
+
+	put_cpu();
 }
 
 /* Free all buffers from the pool */
@@ -3925,7 +3927,7 @@ static inline void mvpp2_bm_pool_put(struct mvpp2_port *port, int pool,
 				     dma_addr_t buf_dma_addr,
 				     phys_addr_t buf_phys_addr)
 {
-	int cpu = smp_processor_id();
+	int cpu = get_cpu();
 
 	if (port->priv->hw_version == MVPP22) {
 		u32 val = 0;
@@ -3952,6 +3954,8 @@ static inline void mvpp2_bm_pool_put(struct mvpp2_port *port, int pool,
 			   MVPP2_BM_VIRT_RLS_REG, buf_phys_addr);
 	mvpp2_percpu_write(port->priv, cpu,
 			   MVPP2_BM_PHY_RLS_REG(pool), buf_dma_addr);
+
+	put_cpu();
 }
 
 /* Refill BM pool */
@@ -4732,7 +4736,7 @@ static void mvpp2_txp_max_tx_size_set(struct mvpp2_port *port)
 static void mvpp2_rx_pkts_coal_set(struct mvpp2_port *port,
 				   struct mvpp2_rx_queue *rxq)
 {
-	int cpu = smp_processor_id();
+	int cpu = get_cpu();
 
 	if (rxq->pkts_coal > MVPP2_OCCUPIED_THRESH_MASK)
 		rxq->pkts_coal = MVPP2_OCCUPIED_THRESH_MASK;
@@ -4740,6 +4744,8 @@ static void mvpp2_rx_pkts_coal_set(struct mvpp2_port *port,
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_RXQ_NUM_REG, rxq->id);
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_RXQ_THRESH_REG,
 			   rxq->pkts_coal);
+
+	put_cpu();
 }
 
 static u32 mvpp2_usec_to_cycles(u32 usec, unsigned long clk_hz)
@@ -4920,7 +4926,7 @@ static int mvpp2_rxq_init(struct mvpp2_port *port,
 	mvpp2_write(port->priv, MVPP2_RXQ_STATUS_REG(rxq->id), 0);
 
 	/* Set Rx descriptors queue starting address - indirect access */
-	cpu = smp_processor_id();
+	cpu = get_cpu();
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_RXQ_NUM_REG, rxq->id);
 	if (port->priv->hw_version == MVPP21)
 		rxq_dma = rxq->descs_dma;
@@ -4929,6 +4935,7 @@ static int mvpp2_rxq_init(struct mvpp2_port *port,
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_RXQ_DESC_ADDR_REG, rxq_dma);
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_RXQ_DESC_SIZE_REG, rxq->size);
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_RXQ_INDEX_REG, 0);
+	put_cpu();
 
 	/* Set Offset */
 	mvpp2_rxq_offset_set(port, rxq->id, NET_SKB_PAD);
@@ -4991,10 +4998,11 @@ static void mvpp2_rxq_deinit(struct mvpp2_port *port,
 	 * free descriptor number
 	 */
 	mvpp2_write(port->priv, MVPP2_RXQ_STATUS_REG(rxq->id), 0);
-	cpu = smp_processor_id();
+	cpu = get_cpu();
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_RXQ_NUM_REG, rxq->id);
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_RXQ_DESC_ADDR_REG, 0);
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_RXQ_DESC_SIZE_REG, 0);
+	put_cpu();
 }
 
 /* Create and initialize a Tx queue */
@@ -5017,7 +5025,7 @@ static int mvpp2_txq_init(struct mvpp2_port *port,
 	txq->last_desc = txq->size - 1;
 
 	/* Set Tx descriptors queue starting address - indirect access */
-	cpu = smp_processor_id();
+	cpu = get_cpu();
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_TXQ_NUM_REG, txq->id);
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_TXQ_DESC_ADDR_REG,
 			   txq->descs_dma);
@@ -5042,6 +5050,7 @@ static int mvpp2_txq_init(struct mvpp2_port *port,
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_TXQ_PREF_BUF_REG,
 			   MVPP2_PREF_BUF_PTR(desc) | MVPP2_PREF_BUF_SIZE_16 |
 			   MVPP2_PREF_BUF_THRESH(desc_per_txq / 2));
+	put_cpu();
 
 	/* WRR / EJP configuration - indirect access */
 	tx_port_num = mvpp2_egress_port(port);
@@ -5112,10 +5121,11 @@ static void mvpp2_txq_deinit(struct mvpp2_port *port,
 	mvpp2_write(port->priv, MVPP2_TXQ_SCHED_TOKEN_CNTR_REG(txq->id), 0);
 
 	/* Set Tx descriptors queue starting address and size */
-	cpu = smp_processor_id();
+	cpu = get_cpu();
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_TXQ_NUM_REG, txq->id);
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_TXQ_DESC_ADDR_REG, 0);
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_TXQ_DESC_SIZE_REG, 0);
+	put_cpu();
 }
 
 /* Cleanup Tx ports */
@@ -5125,7 +5135,7 @@ static void mvpp2_txq_clean(struct mvpp2_port *port, struct mvpp2_tx_queue *txq)
 	int delay, pending, cpu;
 	u32 val;
 
-	cpu = smp_processor_id();
+	cpu = get_cpu();
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_TXQ_NUM_REG, txq->id);
 	val = mvpp2_percpu_read(port->priv, cpu, MVPP2_TXQ_PREF_BUF_REG);
 	val |= MVPP2_TXQ_DRAIN_EN_MASK;
@@ -5152,6 +5162,7 @@ static void mvpp2_txq_clean(struct mvpp2_port *port, struct mvpp2_tx_queue *txq)
 
 	val &= ~MVPP2_TXQ_DRAIN_EN_MASK;
 	mvpp2_percpu_write(port->priv, cpu, MVPP2_TXQ_PREF_BUF_REG, val);
+	put_cpu();
 
 	for_each_present_cpu(cpu) {
 		txq_pcpu = per_cpu_ptr(txq->pcpu, cpu);
-- 
2.9.4

Re: [PATCH v2 0/2] net: mvpp2: driver fixes

[David Miller]

From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Date: Sat, 10 Jun 2017 23:18:20 +0200

> As requested, here is a series of patches containing only bug fixes
> for the mvpp2 driver. It is based on the latest "net" branch.
> 
> Changes since v1:
> 
>  - Fixed a build breakage that occurred when only PATCH 1 was only,
>    and not later patches in the series. Was reported by the kbuild
>    report on the first submission.
> 
>  - Added Tested-by from Marc Zyngier on PATCH 2.

Series applied, thank you.