Re: [PATCH v3 5/6] can: c_can: prepare to up the message objects number

[Marc Kleine-Budde]

On 3/2/21 11:50 AM, Dario Binacchi wrote:
> Hi Marc,
> 
>> Il 01/03/2021 20:45 Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> ha scritto:
>>
>>  
>> On 01.03.2021 18:21:42, Dario Binacchi wrote:
>>>>> @@ -730,7 +728,7 @@ static void c_can_do_tx(struct net_device *dev)
>>>>>  	while ((idx = ffs(pend))) {
>>>>>  		idx--;
>>>>>  		pend &= ~(1 << idx);
>>>>> -		obj = idx + C_CAN_MSG_OBJ_TX_FIRST;
>>>>> +		obj = idx + priv->msg_obj_tx_first;
>>>>>  		c_can_inval_tx_object(dev, IF_TX, obj);
>>>>>  		can_get_echo_skb(dev, idx, NULL);
>>>>>  		bytes += priv->dlc[idx];
>>>>> @@ -740,7 +738,7 @@ static void c_can_do_tx(struct net_device *dev)
>>>>>  	/* Clear the bits in the tx_active mask */
>>>>>  	atomic_sub(clr, &priv->tx_active);
>>>>>  
>>>>> -	if (clr & (1 << (C_CAN_MSG_OBJ_TX_NUM - 1)))
>>>>> +	if (clr & (1 << (priv->msg_obj_tx_num - 1)))
>>>>
>>>> Do we need 1UL here, too?
>>>
>>> Do you agree if I use the BIT macro ?
>>
>> No, please use GENMASK(priv->msg_obj_tx_num, 0) here.
> 
> In case of 64 message objects, msg_obj_tx_num = 32, and 1 << (priv->msg_obj_tx_num - 1) = 0x80000000. 
> GENMASK(priv->msg_obj_tx_num, 0) = 0. 
> BIT(priv->msg_obj_tx_num - 1) = 0x80000000.

Doh! I've misread where the -1 is places.

Marc

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