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* [PATCH 0/2] Enable multiple MCAN on AM62x
@ 2023-07-05 19:53 Judith Mendez
  2023-07-05 19:53 ` [PATCH 1/2] dt-bindings: net: can: Remove interrupt properties for MCAN Judith Mendez
                   ` (2 more replies)
  0 siblings, 3 replies; 9+ messages in thread
From: Judith Mendez @ 2023-07-05 19:53 UTC (permalink / raw)
  To: Chandrasekar Ramakrishnan, Marc Kleine-Budde
  Cc: Wolfgang Grandegger, David S . Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel,
	Schuyler Patton, Tero Kristo, Rob Herring, Krzysztof Kozlowski,
	devicetree, Oliver Hartkopp, Simon Horman

On AM62x there are two MCANs in MCU domain. The MCANs in MCU domain
were not enabled since there is no hardware interrupt routed to A53
GIC interrupt controller. Therefore A53 Linux cannot be interrupted
by MCU MCANs.

This solution instantiates a hrtimer with 1 ms polling interval
for MCAN device when there is no hardware interrupt property in
DTB MCAN node. The hrtimer generates a recurring software interrupt
which allows to call the isr. The isr will check if there is pending
transaction by reading a register and proceed normally if there is.
MCANs with hardware interrupt routed to A53 Linux will continue to
use the hardware interrupt as expected.

Timer polling method was tested on both classic CAN and CAN-FD
at 125 KBPS, 250 KBPS, 1 MBPS and 2.5 MBPS with 4 MBPS bitrate
switching.

Letency and CPU load benchmarks were tested on 3x MCAN on AM62x.
1 MBPS timer polling interval is the better timer polling interval
since it has comparable latency to hardware interrupt with the worse
case being 1ms + CAN frame propagation time and CPU load is not
substantial. Latency can be improved further with less than 1 ms
polling intervals, howerver it is at the cost of CPU usage since CPU
load increases at 0.5 ms.

Note that in terms of power, enabling MCU MCANs with timer-polling
implementation might have negative impact since we will have to wake
up every 1 ms whether there are CAN packets pending in the RX FIFO or
not. This might prevent the CPU from entering into deeper idle states
for extended periods of time.

v8:
Link: https://lore.kernel.org/linux-can/20230530224820.303619-1-jm@ti.com/T/#t

v7:
Link: https://lore.kernel.org/linux-can/20230523023749.4526-1-jm@ti.com/T/#t

v6:
Link: https://lore.kernel.org/linux-can/20230518193613.15185-1-jm@ti.com/T/#t

v5:
Link: https://lore.kernel.org/linux-can/20230510202952.27111-1-jm@ti.com/T/#t

v4:
Link: https://lore.kernel.org/linux-can/c3395692-7dbf-19b2-bd3f-31ba86fa4ac9@linaro.org/T/#t

v2:
Link: https://lore.kernel.org/linux-can/20230424195402.516-1-jm@ti.com/T/#t

V1:
Link: https://lore.kernel.org/linux-can/19d8ae7f-7b74-a869-a818-93b74d106709@ti.com/T/#t

RFC:
Link: https://lore.kernel.org/linux-can/52a37e51-4143-9017-42ee-8d17c67028e3@ti.com/T/#t

v9:
- Change add MS to HRTIMER_POLL_INTERVAL
- Change syntax from "= 0" to "!"

v8:
- Cancel hrtimer after interrupts in m_can_stop
- Move assignment of hrtimer_callback to m_can_class_register()
- Initialize irq = 0 if polling mode is used

v7:
- Clean up m_can_platform.c after removing poll-interval

v6:
- Move hrtimer stop/start function calls to m_can_open and m_can_close to
support power suspend/resume

v5:
- Remove poll-interval in bindings
- Change dev_dbg to dev_info if hardware int exists and polling
is enabled

v4:
- Wrong patches sent

v3:
- Update binding poll-interval description
- Add oneOf to select either
interrupts/798d276b39e984345d52b933a900a71fa0815928

v2:
- Add poll-interval property to bindings and MCAN DTB node
- Add functionality to check for 'poll-interval' property in MCAN node 
- Bindings: add an example using poll-interval
- Add 'polling' flag in driver to check if device is using polling method
- Check for timer polling and hardware interrupt cases, default to
hardware interrupt method
- Change ns_to_ktime() to ms_to_ktime()

Judith Mendez (2):
  dt-bindings: net: can: Remove interrupt properties for MCAN
  can: m_can: Add hrtimer to generate software interrupt

 .../bindings/net/can/bosch,m_can.yaml         | 20 ++++++++++--
 drivers/net/can/m_can/m_can.c                 | 32 ++++++++++++++++++-
 drivers/net/can/m_can/m_can.h                 |  3 ++
 drivers/net/can/m_can/m_can_platform.c        | 23 +++++++++++--
 4 files changed, 72 insertions(+), 6 deletions(-)


base-commit: e1f6a8eaf1c271a0158114a03e3605f4fba059ad
-- 
2.34.1


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH 1/2] dt-bindings: net: can: Remove interrupt properties for MCAN
  2023-07-05 19:53 [PATCH 0/2] Enable multiple MCAN on AM62x Judith Mendez
@ 2023-07-05 19:53 ` Judith Mendez
  2023-07-05 19:53 ` [PATCH 2/2] can: m_can: Add hrtimer to generate software interrupt Judith Mendez
  2023-07-06 20:48 ` [PATCH 0/2] Enable multiple MCAN on AM62x Francesco Dolcini
  2 siblings, 0 replies; 9+ messages in thread
From: Judith Mendez @ 2023-07-05 19:53 UTC (permalink / raw)
  To: Chandrasekar Ramakrishnan, Marc Kleine-Budde
  Cc: Wolfgang Grandegger, David S . Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel,
	Schuyler Patton, Tero Kristo, Rob Herring, Krzysztof Kozlowski,
	devicetree, Oliver Hartkopp, Simon Horman

On AM62x SoC, MCANs on MCU domain do not have hardware interrupt
routed to A53 Linux, instead they will use software interrupt by
timer polling.

To enable timer polling method, interrupts should be
optional so remove interrupts property from required section and
add an example for MCAN node with timer polling enabled.

Reviewed-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Judith Mendez <jm@ti.com>
---
Changelog:
v6-v9:
   1. No changes
v5:
   1. Remove poll-interval
   2. Remove oneOf that selects interrupts/interrupt-names or poll-interval
v3:
   1. Update binding poll-interval description
   2. Add oneOf to select interrupts/interrupt-names or poll-interval
v2:
   1. Add poll-interval property to enable timer polling method
   2. Add example using poll-interval property
---
 .../bindings/net/can/bosch,m_can.yaml         | 20 +++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/can/bosch,m_can.yaml b/Documentation/devicetree/bindings/net/can/bosch,m_can.yaml
index 67879aab623b..bb518c831f7b 100644
--- a/Documentation/devicetree/bindings/net/can/bosch,m_can.yaml
+++ b/Documentation/devicetree/bindings/net/can/bosch,m_can.yaml
@@ -122,8 +122,6 @@ required:
   - compatible
   - reg
   - reg-names
-  - interrupts
-  - interrupt-names
   - clocks
   - clock-names
   - bosch,mram-cfg
@@ -132,6 +130,7 @@ additionalProperties: false
 
 examples:
   - |
+    // Example with interrupts
     #include <dt-bindings/clock/imx6sx-clock.h>
     can@20e8000 {
       compatible = "bosch,m_can";
@@ -149,4 +148,21 @@ examples:
       };
     };
 
+  - |
+    // Example with timer polling
+    #include <dt-bindings/clock/imx6sx-clock.h>
+    can@20e8000 {
+      compatible = "bosch,m_can";
+      reg = <0x020e8000 0x4000>, <0x02298000 0x4000>;
+      reg-names = "m_can", "message_ram";
+      clocks = <&clks IMX6SX_CLK_CANFD>,
+               <&clks IMX6SX_CLK_CANFD>;
+      clock-names = "hclk", "cclk";
+      bosch,mram-cfg = <0x0 0 0 32 0 0 0 1>;
+
+      can-transceiver {
+        max-bitrate = <5000000>;
+      };
+    };
+
 ...
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 2/2] can: m_can: Add hrtimer to generate software interrupt
  2023-07-05 19:53 [PATCH 0/2] Enable multiple MCAN on AM62x Judith Mendez
  2023-07-05 19:53 ` [PATCH 1/2] dt-bindings: net: can: Remove interrupt properties for MCAN Judith Mendez
@ 2023-07-05 19:53 ` Judith Mendez
  2023-07-06  7:25   ` Marc Kleine-Budde
  2023-07-06 20:48 ` [PATCH 0/2] Enable multiple MCAN on AM62x Francesco Dolcini
  2 siblings, 1 reply; 9+ messages in thread
From: Judith Mendez @ 2023-07-05 19:53 UTC (permalink / raw)
  To: Chandrasekar Ramakrishnan, Marc Kleine-Budde
  Cc: Wolfgang Grandegger, David S . Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel,
	Schuyler Patton, Tero Kristo, Rob Herring, Krzysztof Kozlowski,
	devicetree, Oliver Hartkopp, Simon Horman

Introduce timer polling method to MCAN since some SoCs may not
have M_CAN interrupt routed to A53 Linux and do not have
interrupt property in device tree M_CAN node.

On AM62x SoC, MCANs on MCU domain do not have hardware interrupt
routed to A53 Linux, instead they will use timer polling method.

Add an hrtimer to MCAN class device. Each MCAN will have its own
hrtimer instantiated if there is no hardware interrupt found in
device tree M_CAN node. The timer will generate a software
interrupt every 1 ms. In hrtimer callback, we check if there is
a transaction pending by reading a register, then process by
calling the isr if there is.

Tested-by: Hiago De Franco <hiago.franco@toradex.com> # Toradex Verdin AM62
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Judith Mendez <jm@ti.com>
---
Changelog:
v9:
- Change add MS to HRTIMER_POLL_INTERVAL
- Change syntax from "= 0" to "!"
v8:
- Cancel hrtimer after interrupts in m_can_stop
- Move assignment of hrtimer_callback to m_can_class_register()
- Initialize irq = 0 if polling mode is used
- Add reson for polling mode in commit msg
- Remove unrelated change
- Remove polling flag
v7:
- Clean up m_can_platform.c if/else section after removing poll-interval
- Remove poll-interval from patch description
v6:
- Move hrtimer stop/start function calls to m_can_open and m_can_close to
support power suspend/resume
v5:
- Change dev_dbg to dev_info if hardware interrupt exists and polling
is enabled
v4:
- No changes
v3:
- Create a define for 1 ms polling interval
- Change plarform_get_irq to optional to not print error msg
v2:
- Add functionality to check for 'poll-interval' property in MCAN node 
- Add 'polling' flag in driver to check if device is using polling method
- Check for timer polling and hardware interrupt cases, default to
hardware interrupt method
- Change ns_to_ktime() to ms_to_ktime()
---
 drivers/net/can/m_can/m_can.c          | 32 +++++++++++++++++++++++++-
 drivers/net/can/m_can/m_can.h          |  3 +++
 drivers/net/can/m_can/m_can_platform.c | 23 +++++++++++++++---
 3 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index c5af92bcc9c9..13fd84b2e2dd 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -11,6 +11,7 @@
 #include <linux/bitfield.h>
 #include <linux/can/dev.h>
 #include <linux/ethtool.h>
+#include <linux/hrtimer.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
@@ -308,6 +309,9 @@ enum m_can_reg {
 #define TX_EVENT_MM_MASK	GENMASK(31, 24)
 #define TX_EVENT_TXTS_MASK	GENMASK(15, 0)
 
+/* Hrtimer polling interval */
+#define HRTIMER_POLL_INTERVAL_MS		1
+
 /* The ID and DLC registers are adjacent in M_CAN FIFO memory,
  * and we can save a (potentially slow) bus round trip by combining
  * reads and writes to them.
@@ -1414,6 +1418,12 @@ static int m_can_start(struct net_device *dev)
 
 	m_can_enable_all_interrupts(cdev);
 
+	if (!dev->irq) {
+		dev_dbg(cdev->dev, "Start hrtimer\n");
+		hrtimer_start(&cdev->hrtimer, ms_to_ktime(HRTIMER_POLL_INTERVAL_MS),
+			      HRTIMER_MODE_REL_PINNED);
+	}
+
 	return 0;
 }
 
@@ -1568,6 +1578,11 @@ static void m_can_stop(struct net_device *dev)
 {
 	struct m_can_classdev *cdev = netdev_priv(dev);
 
+	if (!dev->irq) {
+		dev_dbg(cdev->dev, "Stop hrtimer\n");
+		hrtimer_cancel(&cdev->hrtimer);
+	}
+
 	/* disable all interrupts */
 	m_can_disable_all_interrupts(cdev);
 
@@ -1793,6 +1808,18 @@ static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
 	return NETDEV_TX_OK;
 }
 
+static enum hrtimer_restart hrtimer_callback(struct hrtimer *timer)
+{
+	struct m_can_classdev *cdev = container_of(timer, struct
+						   m_can_classdev, hrtimer);
+
+	m_can_isr(0, cdev->net);
+
+	hrtimer_forward_now(timer, ms_to_ktime(HRTIMER_POLL_INTERVAL_MS));
+
+	return HRTIMER_RESTART;
+}
+
 static int m_can_open(struct net_device *dev)
 {
 	struct m_can_classdev *cdev = netdev_priv(dev);
@@ -1831,7 +1858,7 @@ static int m_can_open(struct net_device *dev)
 		err = request_threaded_irq(dev->irq, NULL, m_can_isr,
 					   IRQF_ONESHOT,
 					   dev->name, dev);
-	} else {
+	} else if (dev->irq) {
 		err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
 				  dev);
 	}
@@ -2027,6 +2054,9 @@ int m_can_class_register(struct m_can_classdev *cdev)
 			goto clk_disable;
 	}
 
+	if (!cdev->net->irq)
+		cdev->hrtimer.function = &hrtimer_callback;
+
 	ret = m_can_dev_setup(cdev);
 	if (ret)
 		goto rx_offload_del;
diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
index a839dc71dc9b..2ac18ac867a4 100644
--- a/drivers/net/can/m_can/m_can.h
+++ b/drivers/net/can/m_can/m_can.h
@@ -15,6 +15,7 @@
 #include <linux/device.h>
 #include <linux/dma-mapping.h>
 #include <linux/freezer.h>
+#include <linux/hrtimer.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
@@ -93,6 +94,8 @@ struct m_can_classdev {
 	int is_peripheral;
 
 	struct mram_cfg mcfg[MRAM_CFG_NUM];
+
+	struct hrtimer hrtimer;
 };
 
 struct m_can_classdev *m_can_class_allocate_dev(struct device *dev, int sizeof_priv);
diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
index 94dc82644113..76d11ce38220 100644
--- a/drivers/net/can/m_can/m_can_platform.c
+++ b/drivers/net/can/m_can/m_can_platform.c
@@ -5,6 +5,7 @@
 //
 // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/
 
+#include <linux/hrtimer.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
 
@@ -96,12 +97,28 @@ static int m_can_plat_probe(struct platform_device *pdev)
 		goto probe_fail;
 
 	addr = devm_platform_ioremap_resource_byname(pdev, "m_can");
-	irq = platform_get_irq_byname(pdev, "int0");
-	if (IS_ERR(addr) || irq < 0) {
-		ret = -EINVAL;
+	if (IS_ERR(addr)) {
+		ret = PTR_ERR(addr);
 		goto probe_fail;
 	}
 
+	if (device_property_present(mcan_class->dev, "interrupts") ||
+	    device_property_present(mcan_class->dev, "interrupt-names")) {
+		irq = platform_get_irq_byname(pdev, "int0");
+		if (irq == -EPROBE_DEFER) {
+			ret = -EPROBE_DEFER;
+			goto probe_fail;
+		}
+		if (irq < 0) {
+			ret = -EINVAL;
+			goto probe_fail;
+		}
+	} else {
+		dev_dbg(mcan_class->dev, "Polling enabled, initialize hrtimer");
+		hrtimer_init(&mcan_class->hrtimer, CLOCK_MONOTONIC,
+			     HRTIMER_MODE_REL_PINNED);
+	}
+
 	/* message ram could be shared */
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");
 	if (!res) {
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/2] can: m_can: Add hrtimer to generate software interrupt
  2023-07-05 19:53 ` [PATCH 2/2] can: m_can: Add hrtimer to generate software interrupt Judith Mendez
@ 2023-07-06  7:25   ` Marc Kleine-Budde
  2023-07-06 15:20     ` Judith Mendez
  0 siblings, 1 reply; 9+ messages in thread
From: Marc Kleine-Budde @ 2023-07-06  7:25 UTC (permalink / raw)
  To: Judith Mendez
  Cc: Chandrasekar Ramakrishnan, Wolfgang Grandegger, David S . Miller,
	Eric Dumazet, Jakub Kicinski, Paolo Abeni, linux-can, netdev,
	linux-kernel, Schuyler Patton, Tero Kristo, Rob Herring,
	Krzysztof Kozlowski, devicetree, Oliver Hartkopp, Simon Horman

[-- Attachment #1: Type: text/plain, Size: 7602 bytes --]

On 05.07.2023 14:53:56, Judith Mendez wrote:
> Introduce timer polling method to MCAN since some SoCs may not
> have M_CAN interrupt routed to A53 Linux and do not have
> interrupt property in device tree M_CAN node.
> 
> On AM62x SoC, MCANs on MCU domain do not have hardware interrupt
> routed to A53 Linux, instead they will use timer polling method.
> 
> Add an hrtimer to MCAN class device. Each MCAN will have its own
> hrtimer instantiated if there is no hardware interrupt found in
> device tree M_CAN node. The timer will generate a software
> interrupt every 1 ms. In hrtimer callback, we check if there is
> a transaction pending by reading a register, then process by
> calling the isr if there is.
> 
> Tested-by: Hiago De Franco <hiago.franco@toradex.com> # Toradex Verdin AM62
> Reviewed-by: Tony Lindgren <tony@atomide.com>
> Signed-off-by: Judith Mendez <jm@ti.com>
> ---
> Changelog:
> v9:
> - Change add MS to HRTIMER_POLL_INTERVAL
> - Change syntax from "= 0" to "!"
> v8:
> - Cancel hrtimer after interrupts in m_can_stop
> - Move assignment of hrtimer_callback to m_can_class_register()
> - Initialize irq = 0 if polling mode is used

This change has been lost :(

> - Add reson for polling mode in commit msg
> - Remove unrelated change
> - Remove polling flag
> v7:
> - Clean up m_can_platform.c if/else section after removing poll-interval
> - Remove poll-interval from patch description
> v6:
> - Move hrtimer stop/start function calls to m_can_open and m_can_close to
> support power suspend/resume
> v5:
> - Change dev_dbg to dev_info if hardware interrupt exists and polling
> is enabled
> v4:
> - No changes
> v3:
> - Create a define for 1 ms polling interval
> - Change plarform_get_irq to optional to not print error msg
> v2:
> - Add functionality to check for 'poll-interval' property in MCAN node 
> - Add 'polling' flag in driver to check if device is using polling method
> - Check for timer polling and hardware interrupt cases, default to
> hardware interrupt method
> - Change ns_to_ktime() to ms_to_ktime()
> ---
>  drivers/net/can/m_can/m_can.c          | 32 +++++++++++++++++++++++++-
>  drivers/net/can/m_can/m_can.h          |  3 +++
>  drivers/net/can/m_can/m_can_platform.c | 23 +++++++++++++++---
>  3 files changed, 54 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
> index c5af92bcc9c9..13fd84b2e2dd 100644
> --- a/drivers/net/can/m_can/m_can.c
> +++ b/drivers/net/can/m_can/m_can.c
> @@ -11,6 +11,7 @@
>  #include <linux/bitfield.h>
>  #include <linux/can/dev.h>
>  #include <linux/ethtool.h>
> +#include <linux/hrtimer.h>
>  #include <linux/interrupt.h>
>  #include <linux/io.h>
>  #include <linux/iopoll.h>
> @@ -308,6 +309,9 @@ enum m_can_reg {
>  #define TX_EVENT_MM_MASK	GENMASK(31, 24)
>  #define TX_EVENT_TXTS_MASK	GENMASK(15, 0)
>  
> +/* Hrtimer polling interval */
> +#define HRTIMER_POLL_INTERVAL_MS		1
> +
>  /* The ID and DLC registers are adjacent in M_CAN FIFO memory,
>   * and we can save a (potentially slow) bus round trip by combining
>   * reads and writes to them.
> @@ -1414,6 +1418,12 @@ static int m_can_start(struct net_device *dev)
>  
>  	m_can_enable_all_interrupts(cdev);
>  
> +	if (!dev->irq) {
> +		dev_dbg(cdev->dev, "Start hrtimer\n");
> +		hrtimer_start(&cdev->hrtimer, ms_to_ktime(HRTIMER_POLL_INTERVAL_MS),
> +			      HRTIMER_MODE_REL_PINNED);
> +	}
> +
>  	return 0;
>  }
>  
> @@ -1568,6 +1578,11 @@ static void m_can_stop(struct net_device *dev)
>  {
>  	struct m_can_classdev *cdev = netdev_priv(dev);
>  
> +	if (!dev->irq) {
> +		dev_dbg(cdev->dev, "Stop hrtimer\n");
> +		hrtimer_cancel(&cdev->hrtimer);
> +	}
> +
>  	/* disable all interrupts */
>  	m_can_disable_all_interrupts(cdev);
>  
> @@ -1793,6 +1808,18 @@ static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
>  	return NETDEV_TX_OK;
>  }
>  
> +static enum hrtimer_restart hrtimer_callback(struct hrtimer *timer)
> +{
> +	struct m_can_classdev *cdev = container_of(timer, struct
> +						   m_can_classdev, hrtimer);
> +
> +	m_can_isr(0, cdev->net);
> +
> +	hrtimer_forward_now(timer, ms_to_ktime(HRTIMER_POLL_INTERVAL_MS));
> +
> +	return HRTIMER_RESTART;
> +}
> +
>  static int m_can_open(struct net_device *dev)
>  {
>  	struct m_can_classdev *cdev = netdev_priv(dev);
> @@ -1831,7 +1858,7 @@ static int m_can_open(struct net_device *dev)
>  		err = request_threaded_irq(dev->irq, NULL, m_can_isr,
>  					   IRQF_ONESHOT,
>  					   dev->name, dev);
> -	} else {
> +	} else if (dev->irq) {
>  		err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
>  				  dev);
>  	}
> @@ -2027,6 +2054,9 @@ int m_can_class_register(struct m_can_classdev *cdev)
>  			goto clk_disable;
>  	}
>  
> +	if (!cdev->net->irq)
> +		cdev->hrtimer.function = &hrtimer_callback;
> +
>  	ret = m_can_dev_setup(cdev);
>  	if (ret)
>  		goto rx_offload_del;
> diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
> index a839dc71dc9b..2ac18ac867a4 100644
> --- a/drivers/net/can/m_can/m_can.h
> +++ b/drivers/net/can/m_can/m_can.h
> @@ -15,6 +15,7 @@
>  #include <linux/device.h>
>  #include <linux/dma-mapping.h>
>  #include <linux/freezer.h>
> +#include <linux/hrtimer.h>
>  #include <linux/interrupt.h>
>  #include <linux/io.h>
>  #include <linux/iopoll.h>
> @@ -93,6 +94,8 @@ struct m_can_classdev {
>  	int is_peripheral;
>  
>  	struct mram_cfg mcfg[MRAM_CFG_NUM];
> +
> +	struct hrtimer hrtimer;
>  };
>  
>  struct m_can_classdev *m_can_class_allocate_dev(struct device *dev, int sizeof_priv);
> diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
> index 94dc82644113..76d11ce38220 100644
> --- a/drivers/net/can/m_can/m_can_platform.c
> +++ b/drivers/net/can/m_can/m_can_platform.c
> @@ -5,6 +5,7 @@
>  //
>  // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/
>  
> +#include <linux/hrtimer.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
>  
> @@ -96,12 +97,28 @@ static int m_can_plat_probe(struct platform_device *pdev)
>  		goto probe_fail;

Please set "irq" to 0 during declaration.

>  
>  	addr = devm_platform_ioremap_resource_byname(pdev, "m_can");
> -	irq = platform_get_irq_byname(pdev, "int0");
> -	if (IS_ERR(addr) || irq < 0) {
> -		ret = -EINVAL;
> +	if (IS_ERR(addr)) {
> +		ret = PTR_ERR(addr);
>  		goto probe_fail;
>  	}
>  
> +	if (device_property_present(mcan_class->dev, "interrupts") ||
> +	    device_property_present(mcan_class->dev, "interrupt-names")) {
> +		irq = platform_get_irq_byname(pdev, "int0");
> +		if (irq == -EPROBE_DEFER) {
> +			ret = -EPROBE_DEFER;
> +			goto probe_fail;
> +		}
> +		if (irq < 0) {
> +			ret = -EINVAL;

Please return the original error value.

> +			goto probe_fail;
> +		}
> +	} else {
> +		dev_dbg(mcan_class->dev, "Polling enabled, initialize hrtimer");
> +		hrtimer_init(&mcan_class->hrtimer, CLOCK_MONOTONIC,
> +			     HRTIMER_MODE_REL_PINNED);
> +	}
> +
>  	/* message ram could be shared */
>  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");
>  	if (!res) {
> -- 
> 2.34.1
> 
> 

Marc

-- 
Pengutronix e.K.                 | Marc Kleine-Budde          |
Embedded Linux                   | https://www.pengutronix.de |
Vertretung Nürnberg              | Phone: +49-5121-206917-129 |
Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-9   |

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/2] can: m_can: Add hrtimer to generate software interrupt
  2023-07-06  7:25   ` Marc Kleine-Budde
@ 2023-07-06 15:20     ` Judith Mendez
  2023-07-06 20:21       ` Francesco Dolcini
  0 siblings, 1 reply; 9+ messages in thread
From: Judith Mendez @ 2023-07-06 15:20 UTC (permalink / raw)
  To: Marc Kleine-Budde
  Cc: Chandrasekar Ramakrishnan, Wolfgang Grandegger, David S . Miller,
	Eric Dumazet, Jakub Kicinski, Paolo Abeni, linux-can, netdev,
	linux-kernel, Schuyler Patton, Tero Kristo, Rob Herring,
	Krzysztof Kozlowski, devicetree, Oliver Hartkopp, Simon Horman

Hi Marc

On 7/6/23 2:25 AM, Marc Kleine-Budde wrote:
> On 05.07.2023 14:53:56, Judith Mendez wrote:
>> Introduce timer polling method to MCAN since some SoCs may not
>> have M_CAN interrupt routed to A53 Linux and do not have
>> interrupt property in device tree M_CAN node.
>>
>> On AM62x SoC, MCANs on MCU domain do not have hardware interrupt
>> routed to A53 Linux, instead they will use timer polling method.
>>
>> Add an hrtimer to MCAN class device. Each MCAN will have its own
>> hrtimer instantiated if there is no hardware interrupt found in
>> device tree M_CAN node. The timer will generate a software
>> interrupt every 1 ms. In hrtimer callback, we check if there is
>> a transaction pending by reading a register, then process by
>> calling the isr if there is.
>>
>> Tested-by: Hiago De Franco <hiago.franco@toradex.com> # Toradex Verdin AM62
>> Reviewed-by: Tony Lindgren <tony@atomide.com>
>> Signed-off-by: Judith Mendez <jm@ti.com>
>> ---
>> Changelog:
>> v9:
>> - Change add MS to HRTIMER_POLL_INTERVAL
>> - Change syntax from "= 0" to "!"
>> v8:
>> - Cancel hrtimer after interrupts in m_can_stop
>> - Move assignment of hrtimer_callback to m_can_class_register()
>> - Initialize irq = 0 if polling mode is used
> 
> This change has been lost :(

True
> 
>> - Add reson for polling mode in commit msg
>> - Remove unrelated change
>> - Remove polling flag
>> v7:
>> - Clean up m_can_platform.c if/else section after removing poll-interval
>> - Remove poll-interval from patch description
>> v6:
>> - Move hrtimer stop/start function calls to m_can_open and m_can_close to
>> support power suspend/resume
>> v5:
>> - Change dev_dbg to dev_info if hardware interrupt exists and polling
>> is enabled
>> v4:
>> - No changes
>> v3:
>> - Create a define for 1 ms polling interval
>> - Change plarform_get_irq to optional to not print error msg
>> v2:
>> - Add functionality to check for 'poll-interval' property in MCAN node
>> - Add 'polling' flag in driver to check if device is using polling method
>> - Check for timer polling and hardware interrupt cases, default to
>> hardware interrupt method
>> - Change ns_to_ktime() to ms_to_ktime()
>> ---
>>   drivers/net/can/m_can/m_can.c          | 32 +++++++++++++++++++++++++-
>>   drivers/net/can/m_can/m_can.h          |  3 +++
>>   drivers/net/can/m_can/m_can_platform.c | 23 +++++++++++++++---
>>   3 files changed, 54 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
>> index c5af92bcc9c9..13fd84b2e2dd 100644
>> --- a/drivers/net/can/m_can/m_can.c
>> +++ b/drivers/net/can/m_can/m_can.c
>> @@ -11,6 +11,7 @@
>>   #include <linux/bitfield.h>
>>   #include <linux/can/dev.h>
>>   #include <linux/ethtool.h>
>> +#include <linux/hrtimer.h>
>>   #include <linux/interrupt.h>
>>   #include <linux/io.h>
>>   #include <linux/iopoll.h>
>> @@ -308,6 +309,9 @@ enum m_can_reg {
>>   #define TX_EVENT_MM_MASK	GENMASK(31, 24)
>>   #define TX_EVENT_TXTS_MASK	GENMASK(15, 0)
>>   
>> +/* Hrtimer polling interval */
>> +#define HRTIMER_POLL_INTERVAL_MS		1
>> +
>>   /* The ID and DLC registers are adjacent in M_CAN FIFO memory,
>>    * and we can save a (potentially slow) bus round trip by combining
>>    * reads and writes to them.
>> @@ -1414,6 +1418,12 @@ static int m_can_start(struct net_device *dev)
>>   
>>   	m_can_enable_all_interrupts(cdev);
>>   
>> +	if (!dev->irq) {
>> +		dev_dbg(cdev->dev, "Start hrtimer\n");
>> +		hrtimer_start(&cdev->hrtimer, ms_to_ktime(HRTIMER_POLL_INTERVAL_MS),
>> +			      HRTIMER_MODE_REL_PINNED);
>> +	}
>> +
>>   	return 0;
>>   }
>>   
>> @@ -1568,6 +1578,11 @@ static void m_can_stop(struct net_device *dev)
>>   {
>>   	struct m_can_classdev *cdev = netdev_priv(dev);
>>   
>> +	if (!dev->irq) {
>> +		dev_dbg(cdev->dev, "Stop hrtimer\n");
>> +		hrtimer_cancel(&cdev->hrtimer);
>> +	}
>> +
>>   	/* disable all interrupts */
>>   	m_can_disable_all_interrupts(cdev);
>>   
>> @@ -1793,6 +1808,18 @@ static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
>>   	return NETDEV_TX_OK;
>>   }
>>   
>> +static enum hrtimer_restart hrtimer_callback(struct hrtimer *timer)
>> +{
>> +	struct m_can_classdev *cdev = container_of(timer, struct
>> +						   m_can_classdev, hrtimer);
>> +
>> +	m_can_isr(0, cdev->net);
>> +
>> +	hrtimer_forward_now(timer, ms_to_ktime(HRTIMER_POLL_INTERVAL_MS));
>> +
>> +	return HRTIMER_RESTART;
>> +}
>> +
>>   static int m_can_open(struct net_device *dev)
>>   {
>>   	struct m_can_classdev *cdev = netdev_priv(dev);
>> @@ -1831,7 +1858,7 @@ static int m_can_open(struct net_device *dev)
>>   		err = request_threaded_irq(dev->irq, NULL, m_can_isr,
>>   					   IRQF_ONESHOT,
>>   					   dev->name, dev);
>> -	} else {
>> +	} else if (dev->irq) {
>>   		err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
>>   				  dev);
>>   	}
>> @@ -2027,6 +2054,9 @@ int m_can_class_register(struct m_can_classdev *cdev)
>>   			goto clk_disable;
>>   	}
>>   
>> +	if (!cdev->net->irq)
>> +		cdev->hrtimer.function = &hrtimer_callback;
>> +
>>   	ret = m_can_dev_setup(cdev);
>>   	if (ret)
>>   		goto rx_offload_del;
>> diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
>> index a839dc71dc9b..2ac18ac867a4 100644
>> --- a/drivers/net/can/m_can/m_can.h
>> +++ b/drivers/net/can/m_can/m_can.h
>> @@ -15,6 +15,7 @@
>>   #include <linux/device.h>
>>   #include <linux/dma-mapping.h>
>>   #include <linux/freezer.h>
>> +#include <linux/hrtimer.h>
>>   #include <linux/interrupt.h>
>>   #include <linux/io.h>
>>   #include <linux/iopoll.h>
>> @@ -93,6 +94,8 @@ struct m_can_classdev {
>>   	int is_peripheral;
>>   
>>   	struct mram_cfg mcfg[MRAM_CFG_NUM];
>> +
>> +	struct hrtimer hrtimer;
>>   };
>>   
>>   struct m_can_classdev *m_can_class_allocate_dev(struct device *dev, int sizeof_priv);
>> diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
>> index 94dc82644113..76d11ce38220 100644
>> --- a/drivers/net/can/m_can/m_can_platform.c
>> +++ b/drivers/net/can/m_can/m_can_platform.c
>> @@ -5,6 +5,7 @@
>>   //
>>   // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/
>>   
>> +#include <linux/hrtimer.h>
>>   #include <linux/phy/phy.h>
>>   #include <linux/platform_device.h>
>>   
>> @@ -96,12 +97,28 @@ static int m_can_plat_probe(struct platform_device *pdev)
>>   		goto probe_fail;
> 
> Please set "irq" to 0 during declaration.

During declaration of irq, it is already set to 0:

int irq, ret = 0;

> 
>>   
>>   	addr = devm_platform_ioremap_resource_byname(pdev, "m_can");
>> -	irq = platform_get_irq_byname(pdev, "int0");
>> -	if (IS_ERR(addr) || irq < 0) {
>> -		ret = -EINVAL;
>> +	if (IS_ERR(addr)) {
>> +		ret = PTR_ERR(addr);
>>   		goto probe_fail;
>>   	}
>>   
>> +	if (device_property_present(mcan_class->dev, "interrupts") ||
>> +	    device_property_present(mcan_class->dev, "interrupt-names")) {
>> +		irq = platform_get_irq_byname(pdev, "int0");
>> +		if (irq == -EPROBE_DEFER) {
>> +			ret = -EPROBE_DEFER;
>> +			goto probe_fail;
>> +		}
>> +		if (irq < 0) {
>> +			ret = -EINVAL;
> 
> Please return the original error value.

The original value returned is -EINVAL:

-	if (IS_ERR(addr) || irq < 0) {
-		ret = -EINVAL;

Perhaps I am missing something here?

> 
>> +			goto probe_fail;
>> +		}
>> +	} else {
>> +		dev_dbg(mcan_class->dev, "Polling enabled, initialize hrtimer");
>> +		hrtimer_init(&mcan_class->hrtimer, CLOCK_MONOTONIC,
>> +			     HRTIMER_MODE_REL_PINNED);
>> +	}
>> +
>>   	/* message ram could be shared */
>>   	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");
>>   	if (!res) {
>> -- 
>> 2.34.1

Judith

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/2] can: m_can: Add hrtimer to generate software interrupt
  2023-07-06 15:20     ` Judith Mendez
@ 2023-07-06 20:21       ` Francesco Dolcini
  2023-07-06 21:12         ` Judith Mendez
  0 siblings, 1 reply; 9+ messages in thread
From: Francesco Dolcini @ 2023-07-06 20:21 UTC (permalink / raw)
  To: Judith Mendez
  Cc: Marc Kleine-Budde, Chandrasekar Ramakrishnan,
	Wolfgang Grandegger, David S . Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel,
	Schuyler Patton, Tero Kristo, Rob Herring, Krzysztof Kozlowski,
	devicetree, Oliver Hartkopp, Simon Horman

On Thu, Jul 06, 2023 at 10:20:59AM -0500, Judith Mendez wrote:
> Hi Marc
> 
> On 7/6/23 2:25 AM, Marc Kleine-Budde wrote:
> > On 05.07.2023 14:53:56, Judith Mendez wrote:
> > > Introduce timer polling method to MCAN since some SoCs may not
> > > have M_CAN interrupt routed to A53 Linux and do not have
> > > interrupt property in device tree M_CAN node.
> > > 
> > > On AM62x SoC, MCANs on MCU domain do not have hardware interrupt
> > > routed to A53 Linux, instead they will use timer polling method.
> > > 
> > > Add an hrtimer to MCAN class device. Each MCAN will have its own
> > > hrtimer instantiated if there is no hardware interrupt found in
> > > device tree M_CAN node. The timer will generate a software
> > > interrupt every 1 ms. In hrtimer callback, we check if there is
> > > a transaction pending by reading a register, then process by
> > > calling the isr if there is.
> > > 
> > > Tested-by: Hiago De Franco <hiago.franco@toradex.com> # Toradex Verdin AM62
> > > Reviewed-by: Tony Lindgren <tony@atomide.com>
> > > Signed-off-by: Judith Mendez <jm@ti.com>
> > > ---

...

> > > diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
> > > index 94dc82644113..76d11ce38220 100644
> > > --- a/drivers/net/can/m_can/m_can_platform.c
> > > +++ b/drivers/net/can/m_can/m_can_platform.c
> > > @@ -5,6 +5,7 @@
> > >   //
> > >   // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/
> > > +#include <linux/hrtimer.h>
> > >   #include <linux/phy/phy.h>
> > >   #include <linux/platform_device.h>
> > > @@ -96,12 +97,28 @@ static int m_can_plat_probe(struct platform_device *pdev)
> > >   		goto probe_fail;
> > 
> > Please set "irq" to 0 during declaration.
> 
> During declaration of irq, it is already set to 0:
> 
> int irq, ret = 0;

The initialization here applies only to ret.

int irq = 0, ret = 0;

> > >   	addr = devm_platform_ioremap_resource_byname(pdev, "m_can");
> > > -	irq = platform_get_irq_byname(pdev, "int0");
> > > -	if (IS_ERR(addr) || irq < 0) {
> > > -		ret = -EINVAL;
> > > +	if (IS_ERR(addr)) {
> > > +		ret = PTR_ERR(addr);
> > >   		goto probe_fail;
> > >   	}
> > > +	if (device_property_present(mcan_class->dev, "interrupts") ||
> > > +	    device_property_present(mcan_class->dev, "interrupt-names")) {
> > > +		irq = platform_get_irq_byname(pdev, "int0");
> > > +		if (irq == -EPROBE_DEFER) {
> > > +			ret = -EPROBE_DEFER;
> > > +			goto probe_fail;
> > > +		}
> > > +		if (irq < 0) {
> > > +			ret = -EINVAL;
> > 
> > Please return the original error value.
> 
> The original value returned is -EINVAL:
> 
> -	if (IS_ERR(addr) || irq < 0) {
> -		ret = -EINVAL;
> 
> Perhaps I am missing something here?

if (irq < 0) {
	ret = irq;
	...
}

And you can also get rid of the explicit test for -EPROBE_DEFER this
way simplifying the code.

Francesco


^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 0/2] Enable multiple MCAN on AM62x
  2023-07-05 19:53 [PATCH 0/2] Enable multiple MCAN on AM62x Judith Mendez
  2023-07-05 19:53 ` [PATCH 1/2] dt-bindings: net: can: Remove interrupt properties for MCAN Judith Mendez
  2023-07-05 19:53 ` [PATCH 2/2] can: m_can: Add hrtimer to generate software interrupt Judith Mendez
@ 2023-07-06 20:48 ` Francesco Dolcini
  2023-07-06 21:13   ` Judith Mendez
  2 siblings, 1 reply; 9+ messages in thread
From: Francesco Dolcini @ 2023-07-06 20:48 UTC (permalink / raw)
  To: Judith Mendez
  Cc: Chandrasekar Ramakrishnan, Marc Kleine-Budde,
	Wolfgang Grandegger, David S . Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel,
	Schuyler Patton, Tero Kristo, Rob Herring, Krzysztof Kozlowski,
	devicetree, Oliver Hartkopp, Simon Horman

On Wed, Jul 05, 2023 at 02:53:54PM -0500, Judith Mendez wrote:
> v9:
> - Change add MS to HRTIMER_POLL_INTERVAL
> - Change syntax from "= 0" to "!"

Please add the series version to the mail subject, you did it up to v8,
and you forgot now.

Thanks!
Francesco


^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/2] can: m_can: Add hrtimer to generate software interrupt
  2023-07-06 20:21       ` Francesco Dolcini
@ 2023-07-06 21:12         ` Judith Mendez
  0 siblings, 0 replies; 9+ messages in thread
From: Judith Mendez @ 2023-07-06 21:12 UTC (permalink / raw)
  To: Francesco Dolcini
  Cc: Marc Kleine-Budde, Chandrasekar Ramakrishnan,
	Wolfgang Grandegger, David S . Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel,
	Schuyler Patton, Tero Kristo, Rob Herring, Krzysztof Kozlowski,
	devicetree, Oliver Hartkopp, Simon Horman

Hi,

On 7/6/23 3:21 PM, Francesco Dolcini wrote:
> On Thu, Jul 06, 2023 at 10:20:59AM -0500, Judith Mendez wrote:
>> Hi Marc
>>
>> On 7/6/23 2:25 AM, Marc Kleine-Budde wrote:
>>> On 05.07.2023 14:53:56, Judith Mendez wrote:
>>>> Introduce timer polling method to MCAN since some SoCs may not
>>>> have M_CAN interrupt routed to A53 Linux and do not have
>>>> interrupt property in device tree M_CAN node.
>>>>
>>>> On AM62x SoC, MCANs on MCU domain do not have hardware interrupt
>>>> routed to A53 Linux, instead they will use timer polling method.
>>>>
>>>> Add an hrtimer to MCAN class device. Each MCAN will have its own
>>>> hrtimer instantiated if there is no hardware interrupt found in
>>>> device tree M_CAN node. The timer will generate a software
>>>> interrupt every 1 ms. In hrtimer callback, we check if there is
>>>> a transaction pending by reading a register, then process by
>>>> calling the isr if there is.
>>>>
>>>> Tested-by: Hiago De Franco <hiago.franco@toradex.com> # Toradex Verdin AM62
>>>> Reviewed-by: Tony Lindgren <tony@atomide.com>
>>>> Signed-off-by: Judith Mendez <jm@ti.com>
>>>> ---
> 
> ...
> 
>>>> diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
>>>> index 94dc82644113..76d11ce38220 100644
>>>> --- a/drivers/net/can/m_can/m_can_platform.c
>>>> +++ b/drivers/net/can/m_can/m_can_platform.c
>>>> @@ -5,6 +5,7 @@
>>>>    //
>>>>    // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/
>>>> +#include <linux/hrtimer.h>
>>>>    #include <linux/phy/phy.h>
>>>>    #include <linux/platform_device.h>
>>>> @@ -96,12 +97,28 @@ static int m_can_plat_probe(struct platform_device *pdev)
>>>>    		goto probe_fail;
>>>
>>> Please set "irq" to 0 during declaration.
>>
>> During declaration of irq, it is already set to 0:
>>
>> int irq, ret = 0;
> 
> The initialization here applies only to ret.
> 
> int irq = 0, ret = 0;

Understood, thanks!

> 
>>>>    	addr = devm_platform_ioremap_resource_byname(pdev, "m_can");
>>>> -	irq = platform_get_irq_byname(pdev, "int0");
>>>> -	if (IS_ERR(addr) || irq < 0) {
>>>> -		ret = -EINVAL;
>>>> +	if (IS_ERR(addr)) {
>>>> +		ret = PTR_ERR(addr);
>>>>    		goto probe_fail;
>>>>    	}
>>>> +	if (device_property_present(mcan_class->dev, "interrupts") ||
>>>> +	    device_property_present(mcan_class->dev, "interrupt-names")) {
>>>> +		irq = platform_get_irq_byname(pdev, "int0");
>>>> +		if (irq == -EPROBE_DEFER) {
>>>> +			ret = -EPROBE_DEFER;
>>>> +			goto probe_fail;
>>>> +		}
>>>> +		if (irq < 0) {
>>>> +			ret = -EINVAL;
>>>
>>> Please return the original error value.
>>
>> The original value returned is -EINVAL:
>>
>> -	if (IS_ERR(addr) || irq < 0) {
>> -		ret = -EINVAL;
>>
>> Perhaps I am missing something here?
> 
> if (irq < 0) {
> 	ret = irq;
> 	...
> }
> 
> And you can also get rid of the explicit test for -EPROBE_DEFER this
> way simplifying the code.

I misunderstood, thanks!!

~ Judith

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 0/2] Enable multiple MCAN on AM62x
  2023-07-06 20:48 ` [PATCH 0/2] Enable multiple MCAN on AM62x Francesco Dolcini
@ 2023-07-06 21:13   ` Judith Mendez
  0 siblings, 0 replies; 9+ messages in thread
From: Judith Mendez @ 2023-07-06 21:13 UTC (permalink / raw)
  To: Francesco Dolcini
  Cc: Chandrasekar Ramakrishnan, Marc Kleine-Budde,
	Wolfgang Grandegger, David S . Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, linux-can, netdev, linux-kernel,
	Schuyler Patton, Tero Kristo, Rob Herring, Krzysztof Kozlowski,
	devicetree, Oliver Hartkopp, Simon Horman

Hi,

On 7/6/23 3:48 PM, Francesco Dolcini wrote:
> On Wed, Jul 05, 2023 at 02:53:54PM -0500, Judith Mendez wrote:
>> v9:
>> - Change add MS to HRTIMER_POLL_INTERVAL
>> - Change syntax from "= 0" to "!"
> 
> Please add the series version to the mail subject, you did it up to v8,
> and you forgot now.

Thanks Francesco, I will add v10 in next iteration.

~ Judith

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2023-07-06 21:14 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-07-05 19:53 [PATCH 0/2] Enable multiple MCAN on AM62x Judith Mendez
2023-07-05 19:53 ` [PATCH 1/2] dt-bindings: net: can: Remove interrupt properties for MCAN Judith Mendez
2023-07-05 19:53 ` [PATCH 2/2] can: m_can: Add hrtimer to generate software interrupt Judith Mendez
2023-07-06  7:25   ` Marc Kleine-Budde
2023-07-06 15:20     ` Judith Mendez
2023-07-06 20:21       ` Francesco Dolcini
2023-07-06 21:12         ` Judith Mendez
2023-07-06 20:48 ` [PATCH 0/2] Enable multiple MCAN on AM62x Francesco Dolcini
2023-07-06 21:13   ` Judith Mendez

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