All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH net-next v3 0/3]  FEC MDIO speedups
@ 2020-04-19 22:03 Andrew Lunn
  2020-04-19 22:04 ` [PATCH net-next v3 1/3] net: ethernet: fec: Replace interrupt driven MDIO with polled IO Andrew Lunn
                   ` (3 more replies)
  0 siblings, 4 replies; 6+ messages in thread
From: Andrew Lunn @ 2020-04-19 22:03 UTC (permalink / raw)
  To: David Miller
  Cc: netdev, Florian Fainelli, Heiner Kallweit, fugang.duan, Andrew Lunn

This patchset gives a number of speedups for MDIO with the FEC.
Replacing interrupt driven with polled IO brings a big speedup due to
the overheads of interrupts compared to the short time interval.
Clocking the bus faster, when the MDIO targets supports it, can double
the transfer rate. And suppressing the preamble, if devices support
it, makes each transaction faster.

By default the MDIO clock remains 2.5MHz and preables are used. But
these can now be controlled from the device tree. Since these are
generic properties applicable to more than just FEC, these have been
added to the generic MDIO binding documentation.

v2:
readl_poll_timeout()
Add patches to set bus frequency and preamble disable

v3:
Add Reviewed tags
uS->us
readl_poll_timeout_atomic()
Extend DT binding documentation

Andrew Lunn (3):
  net: ethernet: fec: Replace interrupt driven MDIO with polled IO
  net: ethernet: fec: Allow configuration of MDIO bus speed
  net: ethernet: fec: Allow the MDIO preamble to be disabled

 .../devicetree/bindings/net/fsl-fec.txt       |  1 +
 .../devicetree/bindings/net/mdio.yaml         | 12 +++
 drivers/net/ethernet/freescale/fec.h          |  4 +-
 drivers/net/ethernet/freescale/fec_main.c     | 85 +++++++++++--------
 4 files changed, 63 insertions(+), 39 deletions(-)

-- 
2.26.1


^ permalink raw reply	[flat|nested] 6+ messages in thread
* [PATCH net-next v3 1/3] net: ethernet: fec: Replace interrupt driven MDIO with polled IO
  2020-04-19 22:03 [PATCH net-next v3 0/3] FEC MDIO speedups Andrew Lunn
@ 2020-04-19 22:04 ` Andrew Lunn
  2020-04-19 22:04 ` [PATCH net-next v3 2/3] net: ethernet: fec: Allow configuration of MDIO bus speed Andrew Lunn
                   ` (2 subsequent siblings)
  3 siblings, 0 replies; 6+ messages in thread
From: Andrew Lunn @ 2020-04-19 22:04 UTC (permalink / raw)
  To: David Miller
  Cc: netdev, Florian Fainelli, Heiner Kallweit, fugang.duan,
	Andrew Lunn, Chris Heally

Measurements of the MDIO bus have shown that driving the MDIO bus
using interrupts is slow. Back to back MDIO transactions take about
90us, with 25us spent performing the transaction, and the remainder of
the time the bus is idle.

Replacing the completion interrupt with polled IO results in back to
back transactions of 40us. The polling loop waiting for the hardware
to complete the transaction takes around 28us. Which suggests
interrupt handling has an overhead of 50us, and polled IO nearly
halves this overhead, and doubles the MDIO performance.

Suggested-by: Chris Heally <cphealy@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
---
v3:
Use readl_poll_timeout_atomic() which used the accurate udelay()
s/uS/us/g
---
 drivers/net/ethernet/freescale/fec.h      |  4 +-
 drivers/net/ethernet/freescale/fec_main.c | 67 ++++++++++++-----------
 2 files changed, 35 insertions(+), 36 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index e74dd1f86bba..a6cdd5b61921 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -376,8 +376,7 @@ struct bufdesc_ex {
 #define FEC_ENET_TS_AVAIL       ((uint)0x00010000)
 #define FEC_ENET_TS_TIMER       ((uint)0x00008000)
 
-#define FEC_DEFAULT_IMASK (FEC_ENET_TXF | FEC_ENET_RXF | FEC_ENET_MII)
-#define FEC_NAPI_IMASK	FEC_ENET_MII
+#define FEC_DEFAULT_IMASK (FEC_ENET_TXF | FEC_ENET_RXF)
 #define FEC_RX_DISABLED_IMASK (FEC_DEFAULT_IMASK & (~FEC_ENET_RXF))
 
 /* ENET interrupt coalescing macro define */
@@ -543,7 +542,6 @@ struct fec_enet_private {
 	int	link;
 	int	full_duplex;
 	int	speed;
-	struct	completion mdio_done;
 	int	irq[FEC_IRQ_NUM];
 	bool	bufdesc_ex;
 	int	pause_flag;
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index dc6f8763a5d4..2267bf75784e 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -976,8 +976,8 @@ fec_restart(struct net_device *ndev)
 	writel((__force u32)cpu_to_be32(temp_mac[1]),
 	       fep->hwp + FEC_ADDR_HIGH);
 
-	/* Clear any outstanding interrupt. */
-	writel(0xffffffff, fep->hwp + FEC_IEVENT);
+	/* Clear any outstanding interrupt, except MDIO. */
+	writel((0xffffffff & ~FEC_ENET_MII), fep->hwp + FEC_IEVENT);
 
 	fec_enet_bd_init(ndev);
 
@@ -1123,7 +1123,7 @@ fec_restart(struct net_device *ndev)
 	if (fep->link)
 		writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK);
 	else
-		writel(FEC_ENET_MII, fep->hwp + FEC_IMASK);
+		writel(0, fep->hwp + FEC_IMASK);
 
 	/* Init the interrupt coalescing */
 	fec_enet_itr_coal_init(ndev);
@@ -1652,6 +1652,10 @@ fec_enet_interrupt(int irq, void *dev_id)
 	irqreturn_t ret = IRQ_NONE;
 
 	int_events = readl(fep->hwp + FEC_IEVENT);
+
+	/* Don't clear MDIO events, we poll for those */
+	int_events &= ~FEC_ENET_MII;
+
 	writel(int_events, fep->hwp + FEC_IEVENT);
 	fec_enet_collect_events(fep, int_events);
 
@@ -1659,16 +1663,12 @@ fec_enet_interrupt(int irq, void *dev_id)
 		ret = IRQ_HANDLED;
 
 		if (napi_schedule_prep(&fep->napi)) {
-			/* Disable the NAPI interrupts */
-			writel(FEC_NAPI_IMASK, fep->hwp + FEC_IMASK);
+			/* Disable interrupts */
+			writel(0, fep->hwp + FEC_IMASK);
 			__napi_schedule(&fep->napi);
 		}
 	}
 
-	if (int_events & FEC_ENET_MII) {
-		ret = IRQ_HANDLED;
-		complete(&fep->mdio_done);
-	}
 	return ret;
 }
 
@@ -1818,11 +1818,24 @@ static void fec_enet_adjust_link(struct net_device *ndev)
 		phy_print_status(phy_dev);
 }
 
+static int fec_enet_mdio_wait(struct fec_enet_private *fep)
+{
+	uint ievent;
+	int ret;
+
+	ret = readl_poll_timeout_atomic(fep->hwp + FEC_IEVENT, ievent,
+					ievent & FEC_ENET_MII, 2, 30000);
+
+	if (!ret)
+		writel(FEC_ENET_MII, fep->hwp + FEC_IEVENT);
+
+	return ret;
+}
+
 static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
 {
 	struct fec_enet_private *fep = bus->priv;
 	struct device *dev = &fep->pdev->dev;
-	unsigned long time_left;
 	int ret = 0, frame_start, frame_addr, frame_op;
 	bool is_c45 = !!(regnum & MII_ADDR_C45);
 
@@ -1830,8 +1843,6 @@ static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
 	if (ret < 0)
 		return ret;
 
-	reinit_completion(&fep->mdio_done);
-
 	if (is_c45) {
 		frame_start = FEC_MMFR_ST_C45;
 
@@ -1843,11 +1854,9 @@ static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
 		       fep->hwp + FEC_MII_DATA);
 
 		/* wait for end of transfer */
-		time_left = wait_for_completion_timeout(&fep->mdio_done,
-				usecs_to_jiffies(FEC_MII_TIMEOUT));
-		if (time_left == 0) {
+		ret = fec_enet_mdio_wait(fep);
+		if (ret) {
 			netdev_err(fep->netdev, "MDIO address write timeout\n");
-			ret = -ETIMEDOUT;
 			goto out;
 		}
 
@@ -1866,11 +1875,9 @@ static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
 		FEC_MMFR_TA, fep->hwp + FEC_MII_DATA);
 
 	/* wait for end of transfer */
-	time_left = wait_for_completion_timeout(&fep->mdio_done,
-			usecs_to_jiffies(FEC_MII_TIMEOUT));
-	if (time_left == 0) {
+	ret = fec_enet_mdio_wait(fep);
+	if (ret) {
 		netdev_err(fep->netdev, "MDIO read timeout\n");
-		ret = -ETIMEDOUT;
 		goto out;
 	}
 
@@ -1888,7 +1895,6 @@ static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
 {
 	struct fec_enet_private *fep = bus->priv;
 	struct device *dev = &fep->pdev->dev;
-	unsigned long time_left;
 	int ret, frame_start, frame_addr;
 	bool is_c45 = !!(regnum & MII_ADDR_C45);
 
@@ -1898,8 +1904,6 @@ static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
 	else
 		ret = 0;
 
-	reinit_completion(&fep->mdio_done);
-
 	if (is_c45) {
 		frame_start = FEC_MMFR_ST_C45;
 
@@ -1911,11 +1915,9 @@ static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
 		       fep->hwp + FEC_MII_DATA);
 
 		/* wait for end of transfer */
-		time_left = wait_for_completion_timeout(&fep->mdio_done,
-			usecs_to_jiffies(FEC_MII_TIMEOUT));
-		if (time_left == 0) {
+		ret = fec_enet_mdio_wait(fep);
+		if (ret) {
 			netdev_err(fep->netdev, "MDIO address write timeout\n");
-			ret = -ETIMEDOUT;
 			goto out;
 		}
 	} else {
@@ -1931,12 +1933,9 @@ static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
 		fep->hwp + FEC_MII_DATA);
 
 	/* wait for end of transfer */
-	time_left = wait_for_completion_timeout(&fep->mdio_done,
-			usecs_to_jiffies(FEC_MII_TIMEOUT));
-	if (time_left == 0) {
+	ret = fec_enet_mdio_wait(fep);
+	if (ret)
 		netdev_err(fep->netdev, "MDIO write timeout\n");
-		ret  = -ETIMEDOUT;
-	}
 
 out:
 	pm_runtime_mark_last_busy(dev);
@@ -2132,6 +2131,9 @@ static int fec_enet_mii_init(struct platform_device *pdev)
 
 	writel(fep->phy_speed, fep->hwp + FEC_MII_SPEED);
 
+	/* Clear any pending transaction complete indication */
+	writel(FEC_ENET_MII, fep->hwp + FEC_IEVENT);
+
 	fep->mii_bus = mdiobus_alloc();
 	if (fep->mii_bus == NULL) {
 		err = -ENOMEM;
@@ -3674,7 +3676,6 @@ fec_probe(struct platform_device *pdev)
 		fep->irq[i] = irq;
 	}
 
-	init_completion(&fep->mdio_done);
 	ret = fec_enet_mii_init(pdev);
 	if (ret)
 		goto failed_mii_init;
-- 
2.26.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread
* [PATCH net-next v3 2/3] net: ethernet: fec: Allow configuration of MDIO bus speed
  2020-04-19 22:03 [PATCH net-next v3 0/3] FEC MDIO speedups Andrew Lunn
  2020-04-19 22:04 ` [PATCH net-next v3 1/3] net: ethernet: fec: Replace interrupt driven MDIO with polled IO Andrew Lunn
@ 2020-04-19 22:04 ` Andrew Lunn
  2020-04-19 22:04 ` [PATCH net-next v3 3/3] net: ethernet: fec: Allow the MDIO preamble to be disabled Andrew Lunn
  2020-04-20  1:42 ` [EXT] [PATCH net-next v3 0/3] FEC MDIO speedups Andy Duan
  3 siblings, 0 replies; 6+ messages in thread
From: Andrew Lunn @ 2020-04-19 22:04 UTC (permalink / raw)
  To: David Miller
  Cc: netdev, Florian Fainelli, Heiner Kallweit, fugang.duan,
	Andrew Lunn, Chris Healy

MDIO busses typically operate at 2.5MHz. However many devices can
operate at faster speeds. This then allows more MDIO transactions per
second, useful for Ethernet switch statistics, or Ethernet PHY TDR
data. Allow the bus speed to be configured, using the standard
"clock-frequency" property, which i2c busses use to indicate the bus
speed. Before using this property, ensure all devices on the bus do
actually support the requested clock speed.

Suggested-by: Chris Healy <Chris.Healy@zii.aero>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
---
 Documentation/devicetree/bindings/net/fsl-fec.txt |  1 +
 Documentation/devicetree/bindings/net/mdio.yaml   |  6 ++++++
 drivers/net/ethernet/freescale/fec_main.c         | 11 ++++++++---
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/fsl-fec.txt b/Documentation/devicetree/bindings/net/fsl-fec.txt
index ff8b0f211aa1..26c492a2e0e1 100644
--- a/Documentation/devicetree/bindings/net/fsl-fec.txt
+++ b/Documentation/devicetree/bindings/net/fsl-fec.txt
@@ -82,6 +82,7 @@ ethernet@83fec000 {
 	phy-supply = <&reg_fec_supply>;
 	phy-handle = <&ethphy>;
 	mdio {
+	        clock-frequency = <5000000>;
 		ethphy: ethernet-phy@6 {
 			compatible = "ethernet-phy-ieee802.3-c22";
 			reg = <6>;
diff --git a/Documentation/devicetree/bindings/net/mdio.yaml b/Documentation/devicetree/bindings/net/mdio.yaml
index 50c3397a82bc..ab4a9df8b8e2 100644
--- a/Documentation/devicetree/bindings/net/mdio.yaml
+++ b/Documentation/devicetree/bindings/net/mdio.yaml
@@ -39,6 +39,12 @@ properties:
       and must therefore be appropriately determined based on all PHY
       requirements (maximum value of all per-PHY RESET pulse widths).
 
+  clock-frequency:
+    description:
+      Desired MDIO bus clock frequency in Hz. Values greater than IEEE 802.3
+      defined 2.5MHz should only be used when all devices on the bus support
+      the given clock speed.
+
 patternProperties:
   "^ethernet-phy@[0-9a-f]+$":
     type: object
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 2267bf75784e..832a24e2805c 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -2067,6 +2067,7 @@ static int fec_enet_mii_init(struct platform_device *pdev)
 	struct device_node *node;
 	int err = -ENXIO;
 	u32 mii_speed, holdtime;
+	u32 bus_freq;
 
 	/*
 	 * The i.MX28 dual fec interfaces are not equal.
@@ -2094,15 +2095,20 @@ static int fec_enet_mii_init(struct platform_device *pdev)
 		return -ENOENT;
 	}
 
+	bus_freq = 2500000; /* 2.5MHz by default */
+	node = of_get_child_by_name(pdev->dev.of_node, "mdio");
+	if (node)
+		of_property_read_u32(node, "clock-frequency", &bus_freq);
+
 	/*
-	 * Set MII speed to 2.5 MHz (= clk_get_rate() / 2 * phy_speed)
+	 * Set MII speed (= clk_get_rate() / 2 * phy_speed)
 	 *
 	 * The formula for FEC MDC is 'ref_freq / (MII_SPEED x 2)' while
 	 * for ENET-MAC is 'ref_freq / ((MII_SPEED + 1) x 2)'.  The i.MX28
 	 * Reference Manual has an error on this, and gets fixed on i.MX6Q
 	 * document.
 	 */
-	mii_speed = DIV_ROUND_UP(clk_get_rate(fep->clk_ipg), 5000000);
+	mii_speed = DIV_ROUND_UP(clk_get_rate(fep->clk_ipg), bus_freq * 2);
 	if (fep->quirks & FEC_QUIRK_ENET_MAC)
 		mii_speed--;
 	if (mii_speed > 63) {
@@ -2148,7 +2154,6 @@ static int fec_enet_mii_init(struct platform_device *pdev)
 	fep->mii_bus->priv = fep;
 	fep->mii_bus->parent = &pdev->dev;
 
-	node = of_get_child_by_name(pdev->dev.of_node, "mdio");
 	err = of_mdiobus_register(fep->mii_bus, node);
 	of_node_put(node);
 	if (err)
-- 
2.26.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread
* [PATCH net-next v3 3/3] net: ethernet: fec: Allow the MDIO preamble to be disabled
  2020-04-19 22:03 [PATCH net-next v3 0/3] FEC MDIO speedups Andrew Lunn
  2020-04-19 22:04 ` [PATCH net-next v3 1/3] net: ethernet: fec: Replace interrupt driven MDIO with polled IO Andrew Lunn
  2020-04-19 22:04 ` [PATCH net-next v3 2/3] net: ethernet: fec: Allow configuration of MDIO bus speed Andrew Lunn
@ 2020-04-19 22:04 ` Andrew Lunn
  2020-04-20  1:42 ` [EXT] [PATCH net-next v3 0/3] FEC MDIO speedups Andy Duan
  3 siblings, 0 replies; 6+ messages in thread
From: Andrew Lunn @ 2020-04-19 22:04 UTC (permalink / raw)
  To: David Miller
  Cc: netdev, Florian Fainelli, Heiner Kallweit, fugang.duan,
	Andrew Lunn, Chris Healy

An MDIO transaction normally starts with 32 1s as a preamble. However
not all devices requires such a preamble. Add a device tree property
which allows the preamble to be suppressed. This will half the size of
the MDIO transaction, allowing faster transactions. But it should only
be used when all devices on the bus support suppressed preamble.

Suggested-by: Chris Healy <Chris.Healy@zii.aero>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
---
 Documentation/devicetree/bindings/net/mdio.yaml | 6 ++++++
 drivers/net/ethernet/freescale/fec_main.c       | 9 ++++++++-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/net/mdio.yaml b/Documentation/devicetree/bindings/net/mdio.yaml
index ab4a9df8b8e2..cd6c6ae6dabb 100644
--- a/Documentation/devicetree/bindings/net/mdio.yaml
+++ b/Documentation/devicetree/bindings/net/mdio.yaml
@@ -45,6 +45,12 @@ properties:
       defined 2.5MHz should only be used when all devices on the bus support
       the given clock speed.
 
+  suppress-preamble:
+    description:
+      The 32 bit preamble should be suppressed. In order for this to
+      work, all devices on the bus must support suppressed preamble.
+    type: boolean
+
 patternProperties:
   "^ethernet-phy@[0-9a-f]+$":
     type: object
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 832a24e2805c..1ae075a246a3 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -2064,6 +2064,7 @@ static int fec_enet_mii_init(struct platform_device *pdev)
 	static struct mii_bus *fec0_mii_bus;
 	struct net_device *ndev = platform_get_drvdata(pdev);
 	struct fec_enet_private *fep = netdev_priv(ndev);
+	bool suppress_preamble = false;
 	struct device_node *node;
 	int err = -ENXIO;
 	u32 mii_speed, holdtime;
@@ -2097,8 +2098,11 @@ static int fec_enet_mii_init(struct platform_device *pdev)
 
 	bus_freq = 2500000; /* 2.5MHz by default */
 	node = of_get_child_by_name(pdev->dev.of_node, "mdio");
-	if (node)
+	if (node) {
 		of_property_read_u32(node, "clock-frequency", &bus_freq);
+		suppress_preamble = of_property_read_bool(node,
+							  "suppress-preamble");
+	}
 
 	/*
 	 * Set MII speed (= clk_get_rate() / 2 * phy_speed)
@@ -2135,6 +2139,9 @@ static int fec_enet_mii_init(struct platform_device *pdev)
 
 	fep->phy_speed = mii_speed << 1 | holdtime << 8;
 
+	if (suppress_preamble)
+		fep->phy_speed |= BIT(7);
+
 	writel(fep->phy_speed, fep->hwp + FEC_MII_SPEED);
 
 	/* Clear any pending transaction complete indication */
-- 
2.26.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread
* RE: [EXT] [PATCH net-next v3 0/3]  FEC MDIO speedups
  2020-04-19 22:03 [PATCH net-next v3 0/3] FEC MDIO speedups Andrew Lunn
                   ` (2 preceding siblings ...)
  2020-04-19 22:04 ` [PATCH net-next v3 3/3] net: ethernet: fec: Allow the MDIO preamble to be disabled Andrew Lunn
@ 2020-04-20  1:42 ` Andy Duan
  2020-04-20 19:38   ` David Miller
  3 siblings, 1 reply; 6+ messages in thread
From: Andy Duan @ 2020-04-20  1:42 UTC (permalink / raw)
  To: Andrew Lunn, David Miller; +Cc: netdev, Florian Fainelli, Heiner Kallweit

From: Andrew Lunn <andrew@lunn.ch> Sent: Monday, April 20, 2020 6:04 AM
> This patchset gives a number of speedups for MDIO with the FEC.
> Replacing interrupt driven with polled IO brings a big speedup due to the
> overheads of interrupts compared to the short time interval.
> Clocking the bus faster, when the MDIO targets supports it, can double the
> transfer rate. And suppressing the preamble, if devices support it, makes each
> transaction faster.
> 
> By default the MDIO clock remains 2.5MHz and preables are used. But these
> can now be controlled from the device tree. Since these are generic
> properties applicable to more than just FEC, these have been added to the
> generic MDIO binding documentation.
> 
> v2:
> readl_poll_timeout()
> Add patches to set bus frequency and preamble disable
> 
> v3:
> Add Reviewed tags
> uS->us
> readl_poll_timeout_atomic()
> Extend DT binding documentation
> 
> Andrew Lunn (3):
>   net: ethernet: fec: Replace interrupt driven MDIO with polled IO
>   net: ethernet: fec: Allow configuration of MDIO bus speed
>   net: ethernet: fec: Allow the MDIO preamble to be disabled

The v3 version seems good.
Thanks, Andrew.

Acked-by: Fugang Duan <fugang.duan@nxp.com>
> 
>  .../devicetree/bindings/net/fsl-fec.txt       |  1 +
>  .../devicetree/bindings/net/mdio.yaml         | 12 +++
>  drivers/net/ethernet/freescale/fec.h          |  4 +-
>  drivers/net/ethernet/freescale/fec_main.c     | 85 +++++++++++--------
>  4 files changed, 63 insertions(+), 39 deletions(-)
> 
> --
> 2.26.1


^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: [EXT] [PATCH net-next v3 0/3] FEC MDIO speedups
  2020-04-20  1:42 ` [EXT] [PATCH net-next v3 0/3] FEC MDIO speedups Andy Duan
@ 2020-04-20 19:38   ` David Miller
  0 siblings, 0 replies; 6+ messages in thread
From: David Miller @ 2020-04-20 19:38 UTC (permalink / raw)
  To: fugang.duan; +Cc: andrew, netdev, f.fainelli, hkallweit1

From: Andy Duan <fugang.duan@nxp.com>
Date: Mon, 20 Apr 2020 01:42:47 +0000

> From: Andrew Lunn <andrew@lunn.ch> Sent: Monday, April 20, 2020 6:04 AM
>> This patchset gives a number of speedups for MDIO with the FEC.
>> Replacing interrupt driven with polled IO brings a big speedup due to the
>> overheads of interrupts compared to the short time interval.
>> Clocking the bus faster, when the MDIO targets supports it, can double the
>> transfer rate. And suppressing the preamble, if devices support it, makes each
>> transaction faster.
>> 
>> By default the MDIO clock remains 2.5MHz and preables are used. But these
>> can now be controlled from the device tree. Since these are generic
>> properties applicable to more than just FEC, these have been added to the
>> generic MDIO binding documentation.
>> 
>> v2:
>> readl_poll_timeout()
>> Add patches to set bus frequency and preamble disable
>> 
>> v3:
>> Add Reviewed tags
>> uS->us
>> readl_poll_timeout_atomic()
>> Extend DT binding documentation
>> 
>> Andrew Lunn (3):
>>   net: ethernet: fec: Replace interrupt driven MDIO with polled IO
>>   net: ethernet: fec: Allow configuration of MDIO bus speed
>>   net: ethernet: fec: Allow the MDIO preamble to be disabled
> 
> The v3 version seems good.
> Thanks, Andrew.
> 
> Acked-by: Fugang Duan <fugang.duan@nxp.com>

Series applied, thanks everyone.

^ permalink raw reply	[flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-04-20 19:38 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-04-19 22:03 [PATCH net-next v3 0/3] FEC MDIO speedups Andrew Lunn
2020-04-19 22:04 ` [PATCH net-next v3 1/3] net: ethernet: fec: Replace interrupt driven MDIO with polled IO Andrew Lunn
2020-04-19 22:04 ` [PATCH net-next v3 2/3] net: ethernet: fec: Allow configuration of MDIO bus speed Andrew Lunn
2020-04-19 22:04 ` [PATCH net-next v3 3/3] net: ethernet: fec: Allow the MDIO preamble to be disabled Andrew Lunn
2020-04-20  1:42 ` [EXT] [PATCH net-next v3 0/3] FEC MDIO speedups Andy Duan
2020-04-20 19:38   ` David Miller

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.