Re: [PATCH v3 5/5] can: flexcan: add mcf5441x support

[Angelo Dureghello <angelo@kernel-space.org>]

Hi Marc,

On 21/06/21 9:19 PM, Marc Kleine-Budde wrote:
> On 21.06.2021 20:46:15, Angelo Dureghello wrote:
>> Add flexcan support for NXP ColdFire mcf5441x family.
>>
>> This flexcan module is quite similar to imx6 flexcan module, but
>> with some exceptions:
>>
>> - 3 separate interrupt sources, MB, BOFF and ERR,
>> - implements 16 mb only,
>> - m68k architecture is not supporting devicetrees, so a
>>    platform data check/case has been added,
>> - ColdFire is m68k, so big-endian cpu, with a little-endian flexcan
>>    module.
>>
>> Signed-off-by: Angelo Dureghello <angelo@kernel-space.org>
>> ---
>> Changes for v2:
>> - re-add platform data handling restarting from 2c0ac9208135
>> - re-add flexcan_id_table, as from 2c0ac9208135
>> - usinig irq resources for ERR and BOFF interrupts
>> - add missing free_irq() for interrupts
>> - minor syntax fixes
>> Changes for v3:
>> - change platform data include name
>> - add mcf5441x to hw feature flags
>> - add mb column to hw feature flags
>> - fix irq free order
>> - add proper error handlings
>> - remove unrelated changes
>> - split quirk in mb_n and irq_n quirks
>> ---
>>   drivers/net/can/flexcan.c | 126 ++++++++++++++++++++++++++++++++------
>>   1 file changed, 106 insertions(+), 20 deletions(-)
>>
>> diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
>> index 57f3635ad8d7..123737be2d6b 100644
>> --- a/drivers/net/can/flexcan.c
>> +++ b/drivers/net/can/flexcan.c
>> @@ -28,6 +28,7 @@
>>   #include <linux/of_device.h>
>>   #include <linux/pinctrl/consumer.h>
>>   #include <linux/platform_device.h>
>> +#include <linux/can/platform/flexcan.h>
>>   #include <linux/pm_runtime.h>
>>   #include <linux/regmap.h>
>>   #include <linux/regulator/consumer.h>
>> @@ -208,18 +209,19 @@
>>   /* FLEXCAN hardware feature flags
>>    *
>>    * Below is some version info we got:
>> - *    SOC   Version   IP-Version  Glitch- [TR]WRN_INT IRQ Err Memory err RTR rece-   FD Mode
>> + *    SOC   Version   IP-Version  Glitch- [TR]WRN_INT IRQ Err Memory err RTR rece-   FD Mode     MB
>>    *                                Filter? connected?  Passive detection  ption in MB Supported?
>> - *   MX25  FlexCAN2  03.00.00.00     no        no        no       no        no           no
>> - *   MX28  FlexCAN2  03.00.04.00    yes       yes        no       no        no           no
>> - *   MX35  FlexCAN2  03.00.00.00     no        no        no       no        no           no
>> - *   MX53  FlexCAN2  03.00.00.00    yes        no        no       no        no           no
>> - *   MX6s  FlexCAN3  10.00.12.00    yes       yes        no       no       yes           no
>> - *   MX8QM FlexCAN3  03.00.23.00    yes       yes        no       no       yes          yes
>> - *   MX8MP FlexCAN3  03.00.17.01    yes       yes        no      yes       yes          yes
>> - *   VF610 FlexCAN3  ?               no       yes        no      yes       yes?          no
>> - * LS1021A FlexCAN2  03.00.04.00     no       yes        no       no       yes           no
>> - * LX2160A FlexCAN3  03.00.23.00     no       yes        no      yes       yes          yes
>> + *   MX25   FlexCAN2  03.00.00.00     no        no        no       no        no           no     64
>> + *   MX28   FlexCAN2  03.00.04.00    yes       yes        no       no        no           no     64
>> + *   MX35   FlexCAN2  03.00.00.00     no        no        no       no        no           no     64
>> + *   MX53   FlexCAN2  03.00.00.00    yes        no        no       no        no           no     64
>> + *   MX6s   FlexCAN3  10.00.12.00    yes       yes        no       no       yes           no     64
>> + *   MX8QM  FlexCAN3  03.00.23.00    yes       yes        no       no       yes          yes     64
>> + *   MX8MP  FlexCAN3  03.00.17.01    yes       yes        no      yes       yes          yes     64
>> + *   VF610  FlexCAN3  ?               no       yes        no      yes       yes?          no     64
>> + * LS1021A  FlexCAN2  03.00.04.00     no       yes        no       no       yes           no     64
>> + * LX2160A  FlexCAN3  03.00.23.00     no       yes        no      yes       yes          yes     64
>> + * MCF5441X FlexCAN2  ?               no       yes        no       no       yes           no     16
>>    *
>>    * Some SOCs do not have the RX_WARN & TX_WARN interrupt line connected.
>>    */
>> @@ -246,6 +248,10 @@
>>   #define FLEXCAN_QUIRK_SUPPORT_ECC BIT(10)
>>   /* Setup stop mode with SCU firmware to support wakeup */
>>   #define FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW BIT(11)
>> +/* Setup 3 separate interrupts, main, boff and err */
>> +#define FLEXCAN_QUIRK_NR_IRQ_3 BIT(12)
>> +/* Setup 16 mailboxes */
>> +#define FLEXCAN_QUIRK_NR_MB_16 BIT(13)
>>   
>>   /* Structure of the message buffer */
>>   struct flexcan_mb {
>> @@ -363,6 +369,9 @@ struct flexcan_priv {
>>   	struct regulator *reg_xceiver;
>>   	struct flexcan_stop_mode stm;
>>   
>> +	int irq_boff;
>> +	int irq_err;
>> +
>>   	/* IPC handle when setup stop mode by System Controller firmware(scfw) */
>>   	struct imx_sc_ipc *sc_ipc_handle;
>>   
>> @@ -371,6 +380,11 @@ struct flexcan_priv {
>>   	void (*write)(u32 val, void __iomem *addr);
>>   };
>>   
>> +static const struct flexcan_devtype_data fsl_mcf5441x_devtype_data = {
>> +	.quirks = FLEXCAN_QUIRK_BROKEN_PERR_STATE |
>> +		FLEXCAN_QUIRK_NR_IRQ_3 | FLEXCAN_QUIRK_NR_MB_16,
>> +};
>> +
>>   static const struct flexcan_devtype_data fsl_p1010_devtype_data = {
>>   	.quirks = FLEXCAN_QUIRK_BROKEN_WERR_STATE |
>>   		FLEXCAN_QUIRK_BROKEN_PERR_STATE |
>> @@ -637,13 +651,17 @@ static int flexcan_clks_enable(const struct flexcan_priv *priv)
>>   {
>>   	int err;
>>   
>> -	err = clk_prepare_enable(priv->clk_ipg);
>> -	if (err)
>> -		return err;
>> +	if (priv->clk_ipg) {
>> +		err = clk_prepare_enable(priv->clk_ipg);
>> +		if (err)
>> +			return err;
>> +	}
>>   
>> -	err = clk_prepare_enable(priv->clk_per);
>> -	if (err)
>> -		clk_disable_unprepare(priv->clk_ipg);
>> +	if (priv->clk_per) {
>> +		err = clk_prepare_enable(priv->clk_per);
>> +		if (err)
>> +			clk_disable_unprepare(priv->clk_ipg);
>> +	}
>>   
>>   	return err;
>>   }
>> @@ -1401,8 +1419,12 @@ static int flexcan_rx_offload_setup(struct net_device *dev)
>>   		priv->mb_size = sizeof(struct flexcan_mb) + CANFD_MAX_DLEN;
>>   	else
>>   		priv->mb_size = sizeof(struct flexcan_mb) + CAN_MAX_DLEN;
>> -	priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) +
>> -			 (sizeof(priv->regs->mb[1]) / priv->mb_size);
>> +
>> +	if (priv->devtype_data->quirks & FLEXCAN_QUIRK_NR_MB_16)
>> +		priv->mb_count = FLEXCAN_MCF5411X_MB_CNT_MCF;
>> +	else
>> +		priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) +
>> +				 (sizeof(priv->regs->mb[1]) / priv->mb_size);
>>   
>>   	if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP)
>>   		priv->tx_mb_reserved =
>> @@ -1774,6 +1796,18 @@ static int flexcan_open(struct net_device *dev)
>>   	if (err)
>>   		goto out_can_rx_offload_disable;
>>   
>> +	if (priv->devtype_data->quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
>> +		err = request_irq(priv->irq_boff,
>> +				  flexcan_irq, IRQF_SHARED, dev->name, dev);
>> +		if (err)
>> +			goto out_can_irq_disable;
> 
> out_free_irq
> 
>> +
>> +		err = request_irq(priv->irq_err,
>> +				  flexcan_irq, IRQF_SHARED, dev->name, dev);
>> +		if (err)
>> +			goto out_can_irq_boff_disable;
> 
> out_free_irq_boff
> 
>> +	}
>> +
>>   	flexcan_chip_interrupts_enable(dev);
>>   
>>   	can_led_event(dev, CAN_LED_EVENT_OPEN);
>> @@ -1782,6 +1816,10 @@ static int flexcan_open(struct net_device *dev)
>>   
>>   	return 0;
>>   
>> + out_can_irq_boff_disable:
>> +	free_irq(priv->irq_boff, dev);
>> + out_can_irq_disable:
>> +	free_irq(dev->irq, dev);
>>    out_can_rx_offload_disable:
>>   	can_rx_offload_disable(&priv->offload);
>>   	flexcan_chip_stop(dev);
>> @@ -1803,6 +1841,12 @@ static int flexcan_close(struct net_device *dev)
>>   
>>   	netif_stop_queue(dev);
>>   	flexcan_chip_interrupts_disable(dev);
>> +
>> +	if (priv->devtype_data->quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
>> +		free_irq(priv->irq_err, dev);
>> +		free_irq(priv->irq_boff, dev);
>> +	}
>> +
>>   	free_irq(dev->irq, dev);
>>   	can_rx_offload_disable(&priv->offload);
>>   	flexcan_chip_stop_disable_on_error(dev);
>> @@ -2039,14 +2083,26 @@ static const struct of_device_id flexcan_of_match[] = {
>>   };
>>   MODULE_DEVICE_TABLE(of, flexcan_of_match);
>>   
>> +static const struct platform_device_id flexcan_id_table[] = {
>> +	{
>> +		.name = "flexcan-mcf5441x",
>> +		.driver_data = (kernel_ulong_t)&fsl_mcf5441x_devtype_data,
>> +	}, {
>> +		/* sentinel */
>> +	},
>> +};
>> +MODULE_DEVICE_TABLE(platform, flexcan_id_table);
>> +
>>   static int flexcan_probe(struct platform_device *pdev)
>>   {
>> +	const struct of_device_id *of_id;
>>   	const struct flexcan_devtype_data *devtype_data;
>>   	struct net_device *dev;
>>   	struct flexcan_priv *priv;
>>   	struct regulator *reg_xceiver;
>>   	struct clk *clk_ipg = NULL, *clk_per = NULL;
>>   	struct flexcan_regs __iomem *regs;
>> +	struct mcf_flexcan_platform_data *pdata;
>>   	int err, irq;
>>   	u8 clk_src = 1;
>>   	u32 clock_freq = 0;
>> @@ -2064,6 +2120,12 @@ static int flexcan_probe(struct platform_device *pdev)
>>   				     "clock-frequency", &clock_freq);
>>   		of_property_read_u8(pdev->dev.of_node,
>>   				    "fsl,clk-source", &clk_src);
>> +	} else {
>> +		pdata = dev_get_platdata(&pdev->dev);
>> +		if (pdata) {
>> +			clock_freq = pdata->clock_frequency;
>> +			clk_src = pdata->clk_src;
>> +		}
>>   	}
>>   
>>   	if (!clock_freq) {
>> @@ -2089,7 +2151,14 @@ static int flexcan_probe(struct platform_device *pdev)
>>   	if (IS_ERR(regs))
>>   		return PTR_ERR(regs);
>>   
>> -	devtype_data = of_device_get_match_data(&pdev->dev);
>> +	of_id = of_match_device(flexcan_of_match, &pdev->dev);
>> +	if (of_id)
>> +		devtype_data = of_id->data;
>> +	else if (platform_get_device_id(pdev)->driver_data)
>> +		devtype_data = (struct flexcan_devtype_data *)
>> +			platform_get_device_id(pdev)->driver_data;
>> +	else
>> +		return -ENODEV;
>>   
>>   	if ((devtype_data->quirks & FLEXCAN_QUIRK_SUPPORT_FD) &&
>>   	    !(devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP)) {
>> @@ -2133,6 +2202,19 @@ static int flexcan_probe(struct platform_device *pdev)
>>   	priv->devtype_data = devtype_data;
>>   	priv->reg_xceiver = reg_xceiver;
>>   
>> +	if (devtype_data->quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
>> +		priv->irq_boff = platform_get_irq(pdev, 1);
>> +		if (priv->irq_boff <= 0) {
>> +			err = -ENODEV;
>> +			goto failed_get_irq_boff;
>> +		}
>> +		priv->irq_err = platform_get_irq(pdev, 2);
>> +		if (priv->irq_err <= 0) {
>> +			err = -ENODEV;
>> +			goto failed_get_irq_err;
>> +		}
>> +	}
> 
> I suggest to move this directly after the platform_get_irq(pdev, 0),
> that makes error handling a lot easier.
> 

Moving that above can't be done, devtype_data is still not
assigned and i get seg. fault.

I can eventually move
irq = platform_get_irq(pdev, 0);

just before

if (devtype_data->quirks & FLEXCAN_QUIRK_NR_IRQ_3)


>> +
>>   	if (priv->devtype_data->quirks & FLEXCAN_QUIRK_SUPPORT_FD) {
>>   		priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD |
>>   			CAN_CTRLMODE_FD_NON_ISO;
>> @@ -2170,6 +2252,9 @@ static int flexcan_probe(struct platform_device *pdev)
>>    failed_register:
>>   	pm_runtime_put_noidle(&pdev->dev);
>>   	pm_runtime_disable(&pdev->dev);
>> + failed_get_irq_err:
>> +	free_irq(priv->irq_boff, dev);
> 
> This is wrong - you cannot free an IRQ you have not requested.
> 
>> + failed_get_irq_boff:
>>   	free_candev(dev);
>>   	return err;
>>   }
>> @@ -2322,6 +2407,7 @@ static struct platform_driver flexcan_driver = {
>>   	},
>>   	.probe = flexcan_probe,
>>   	.remove = flexcan_remove,
>> +	.id_table = flexcan_id_table,
>>   };
>>   
>>   module_platform_driver(flexcan_driver);
>> -- 
>> 2.31.1
>>
>>
> 
> Marc
> 

All the rest is fixed,7

Thanks !
Regards,
angelo