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can: c_can: remove obsolete STRICT_FRAME_ORDERING Kconfig option

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In 2b9aecdce2 ("can: c_can: Disable rx split as workaround") a new Kconfig
option was introduced as a workaround. The tests performed by Alexander Stein
confirmed this option to be obsolete with all the other cleanups and fixes
that had been discussed that time:
http://marc.info/?l=linux-can&m=139746476821294&w=2

Both (author and tester) agreed to remove this Kconfig option again:
http://marc.info/?l=linux-can&m=139883820714229&w=2

As some more cleanups took place since then a simple revert is not possible.
This patch removes the entire option as it would behave when disabled.
Further beautification’s can be done later.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Oliver Hartkopp 2014-05-06 19:45:38 +02:00 committed by Marc Kleine-Budde
parent 4f337ed5c0
commit 524369e239
2 changed files with 0 additions and 43 deletions
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7
drivers/net/can/c_can/Kconfig
View file

@ -14,13 +14,6 @@ config CAN_C_CAN_PLATFORM
SPEAr1310 and SPEAr320 evaluation boards & TI (www.ti.com)
boards like am335x, dm814x, dm813x and dm811x.
config CAN_C_CAN_STRICT_FRAME_ORDERING
bool "Force a strict RX CAN frame order (may cause frame loss)"
---help---
The RX split buffer prevents packet reordering but can cause packet
loss. Only enable this option when you accept to lose CAN frames
in favour of getting the received CAN frames in the correct order.
config CAN_C_CAN_PCI
tristate "Generic PCI Bus based C_CAN/D_CAN driver"
depends on PCI

36
drivers/net/can/c_can/c_can.c
View file

@ -732,26 +732,12 @@ static u32 c_can_adjust_pending(u32 pend)
static inline void c_can_rx_object_get(struct net_device *dev,
struct c_can_priv *priv, u32 obj)
{
#ifdef CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING
if (obj < C_CAN_MSG_RX_LOW_LAST)
c_can_object_get(dev, IF_RX, obj, IF_COMM_RCV_LOW);
else
#endif
c_can_object_get(dev, IF_RX, obj, priv->comm_rcv_high);
}
static inline void c_can_rx_finalize(struct net_device *dev,
struct c_can_priv *priv, u32 obj)
{
#ifdef CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING
if (obj < C_CAN_MSG_RX_LOW_LAST)
priv->rxmasked |= BIT(obj - 1);
else if (obj == C_CAN_MSG_RX_LOW_LAST) {
priv->rxmasked = 0;
/* activate all lower message objects */
c_can_activate_all_lower_rx_msg_obj(dev, IF_RX);
}
#endif
if (priv->type != BOSCH_D_CAN)
c_can_object_get(dev, IF_RX, obj, IF_COMM_CLR_NEWDAT);
}
@ -799,9 +785,6 @@ static inline u32 c_can_get_pending(struct c_can_priv *priv)
{
u32 pend = priv->read_reg(priv, C_CAN_NEWDAT1_REG);
#ifdef CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING
pend &= ~priv->rxmasked;
#endif
return pend;
}
@ -814,25 +797,6 @@ static inline u32 c_can_get_pending(struct c_can_priv *priv)
* has arrived. To work-around this issue, we keep two groups of message
* objects whose partitioning is defined by C_CAN_MSG_OBJ_RX_SPLIT.
*
* If CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING = y
*
* To ensure in-order frame reception we use the following
* approach while re-activating a message object to receive further
* frames:
* - if the current message object number is lower than
* C_CAN_MSG_RX_LOW_LAST, do not clear the NEWDAT bit while clearing
* the INTPND bit.
* - if the current message object number is equal to
* C_CAN_MSG_RX_LOW_LAST then clear the NEWDAT bit of all lower
* receive message objects.
* - if the current message object number is greater than
* C_CAN_MSG_RX_LOW_LAST then clear the NEWDAT bit of
* only this message object.
*
* This can cause packet loss!
*
* If CONFIG_CAN_C_CAN_STRICT_FRAME_ORDERING = n
*
* We clear the newdat bit right away.
*
* This can result in packet reordering when the readout is slow.