arm64: dts: stratix10: Support Ethernet Jumbo frame

From: Thor Thayer <[email protected]>

Properly specify the RX and TX FIFO size which is important for Jumbo frames.
Update the max-frame-size to support Jumbo frames.

---
v2 Shorten title. No change to DTS.

---
 arch/arm64/boot/dts/altera/socfpga_stratix10.dtsi      | 6 ++++++
 arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dts | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

index d033da401c26..8a2641c742ae 100644
@@ -137,6 +137,8 @@
 			reset-names = "stmmaceth", "stmmaceth-ocp";
 			clocks = <&clkmgr STRATIX10_EMAC0_CLK>;
 			clock-names = "stmmaceth";
+			tx-fifo-depth = <16384>;
+			rx-fifo-depth = <16384>;
 			status = "disabled";
 		};
 

@@ -150,6 +152,8 @@
 			reset-names = "stmmaceth", "stmmaceth-ocp";
 			clocks = <&clkmgr STRATIX10_EMAC1_CLK>;
 			clock-names = "stmmaceth";
+			tx-fifo-depth = <16384>;
+			rx-fifo-depth = <16384>;
 			status = "disabled";
 		};
 

@@ -163,6 +167,8 @@
 			reset-names = "stmmaceth", "stmmaceth-ocp";
 			clocks = <&clkmgr STRATIX10_EMAC2_CLK>;
 			clock-names = "stmmaceth";
+			tx-fifo-depth = <16384>;
+			rx-fifo-depth = <16384>;
 			status = "disabled";
 		};
 

index 6edc4fa9fd42..7c661753bfaf 100644
@@ -76,7 +76,7 @@
 	phy-mode = "rgmii";
 	phy-handle = <&phy0>;
 
-	max-frame-size = <3800>;
+	max-frame-size = <9000>;
 
 	mdio0 {
 		#address-cells = <1>;

2.7.4

From: Thor Thayer <[email protected]>

Ping with Jumbo packet does not reply and get a watchdog timeout

[   46.059616] ------------[ cut here ]------------
[   46.064268] NETDEV WATCHDOG: eth0 (socfpga-dwmac): transmit queue 0 timed out
[   46.071471] WARNING: CPU: 1 PID: 0 at net/sched/sch_generic.c:461 dev_watchdog+0x2cc/0x2d8
[   46.079708] Modules linked in:
[   46.082761] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.18.0-00115-gc262be665854-dirty #264
[   46.091082] Hardware name: SoCFPGA Stratix 10 SoCDK (DT)
[   46.096377] pstate: 20000005 (nzCv daif -PAN -UAO)
[   46.101152] pc : dev_watchdog+0x2cc/0x2d8
[   46.105149] lr : dev_watchdog+0x2cc/0x2d8
[   46.109144] sp : ffff00000800bd80
[   46.112447] x29: ffff00000800bd80 x28: ffff80007a9b4940
[   46.117744] x27: 00000000ffffffff x26: ffff80007aa183b0
[   46.123040] x25: 0000000000000001 x24: 0000000000000140
[   46.128336] x23: ffff80007aa1839c x22: ffff80007aa17fb0
[   46.133632] x21: ffff80007aa18000 x20: ffff0000091a7000
[   46.138927] x19: 0000000000000000 x18: ffffffffffffffff
[   46.144223] x17: 0000000000000000 x16: 0000000000000000
[   46.149519] x15: ffff0000091a96c8 x14: 07740775076f0720
[   46.154814] x13: 07640765076d0769 x12: 0774072007300720
[   46.160110] x11: 0765077507650775 x10: 0771072007740769
[   46.165406] x9 : 076d0773076e0761 x8 : 077207740720073a
[   46.170702] x7 : 072907630761076d x6 : ffff80007ff9a0c0
[   46.175997] x5 : ffff80007ff9a0c0 x4 : 0000000000000002
[   46.181293] x3 : 0000000000000000 x2 : ffff0000091ac180
[   46.186589] x1 : e6a742ebe628e800 x0 : 0000000000000000
[   46.191885] Call trace:
[   46.194326]  dev_watchdog+0x2cc/0x2d8
[   46.197980]  call_timer_fn+0x20/0x78
[   46.201544]  expire_timers+0xa4/0xb0
[   46.205108]  run_timer_softirq+0xe4/0x198
[   46.209107]  __do_softirq+0x114/0x210
[   46.212760]  irq_exit+0xd0/0xd8
[   46.215895]  __handle_domain_irq+0x60/0xb0
[   46.219977]  gic_handle_irq+0x58/0xa8
[   46.223628]  el1_irq+0xb0/0x128
[   46.226761]  arch_cpu_idle+0x10/0x18
[   46.230326]  do_idle+0x1d4/0x288
[   46.233544]  cpu_startup_entry+0x24/0x28
[   46.237457]  secondary_start_kernel+0x17c/0x1c0
[   46.241971] ---[ end trace 57048cd1372cd828 ]---

Inspection of queue showed Jumbo packets were not sent out. The ring Jumbo packet function needs to set the OWN bit so the packet is sent.

---
v2 Add fix for jumbo frames > 8K (same OWN bit)

---
 drivers/net/ethernet/stmicro/stmmac/ring_mode.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

index a7ffc73fffe8..abc3f85270cd 100644
@@ -59,7 +59,7 @@ static int jumbo_frm(void *p, struct sk_buff *skb, int csum)
 
 		desc->des3 = cpu_to_le32(des2 + BUF_SIZE_4KiB);
 		stmmac_prepare_tx_desc(priv, desc, 1, bmax, csum,
-				STMMAC_RING_MODE, 0, false, skb->len);
+				STMMAC_RING_MODE, 1, false, skb->len);
 		tx_q->tx_skbuff[entry] = NULL;
 		entry = STMMAC_GET_ENTRY(entry, DMA_TX_SIZE);
 

@@ -91,7 +91,7 @@ static int jumbo_frm(void *p, struct sk_buff *skb, int csum)
 		tx_q->tx_skbuff_dma[entry].is_jumbo = true;
 		desc->des3 = cpu_to_le32(des2 + BUF_SIZE_4KiB);
 		stmmac_prepare_tx_desc(priv, desc, 1, nopaged_len, csum,
-				STMMAC_RING_MODE, 0, true, skb->len);
+				STMMAC_RING_MODE, 1, true, skb->len);
 	}
 
 	tx_q->cur_tx = entry;

2.7.4

From: [email protected]
Date: Mon, 22 Oct 2018 17:22:26 -0500

...

Applied.

From: [email protected]
Date: Mon, 22 Oct 2018 17:22:25 -0500

Applied.