From 4f72e5f00dea3eca9139a23cf70fbf18d62fd1db Mon Sep 17 00:00:00 2001 From: Wolfgang Grandegger Date: Fri, 28 Sep 2012 03:17:15 +0000 Subject: flexcan: disable bus error interrupts for the i.MX28 Due to a bug in most Flexcan cores, the bus error interrupt needs to be enabled. Otherwise we don't get any error warning or passive interrupts. This is _not_ necessary for the i.MX28 and this patch disables bus error interrupts if "berr-reporting" is not requested. This avoids bus error flooding, which might harm, especially on low-end systems. To handle such quirks of the Flexcan cores, a hardware feature flag has been introduced, also replacing the "hw_ver" variable. So far nobody could tell what Flexcan core version is available on what Freescale SOC, apart from the i.MX6Q and P1010, and which bugs or features are present on the various "hw_rev". CC: Hui Wang CC: Shawn Guo Signed-off-by: Wolfgang Grandegger Signed-off-by: David S. Miller --- drivers/net/can/flexcan.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) (limited to 'drivers/net/can/flexcan.c') diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index c5f143165f8..c78ecfca1e4 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -144,6 +144,10 @@ #define FLEXCAN_MB_CODE_MASK (0xf0ffffff) +/* FLEXCAN hardware feature flags */ +#define FLEXCAN_HAS_V10_FEATURES BIT(1) /* For core version >= 10 */ +#define FLEXCAN_HAS_BROKEN_ERR_STATE BIT(2) /* Broken error state handling */ + /* Structure of the message buffer */ struct flexcan_mb { u32 can_ctrl; @@ -178,7 +182,7 @@ struct flexcan_regs { }; struct flexcan_devtype_data { - u32 hw_ver; /* hardware controller version */ + u32 features; /* hardware controller features */ }; struct flexcan_priv { @@ -197,11 +201,11 @@ struct flexcan_priv { }; static struct flexcan_devtype_data fsl_p1010_devtype_data = { - .hw_ver = 3, + .features = FLEXCAN_HAS_BROKEN_ERR_STATE, }; - +static struct flexcan_devtype_data fsl_imx28_devtype_data; static struct flexcan_devtype_data fsl_imx6q_devtype_data = { - .hw_ver = 10, + .features = FLEXCAN_HAS_V10_FEATURES | FLEXCAN_HAS_BROKEN_ERR_STATE, }; static const struct can_bittiming_const flexcan_bittiming_const = { @@ -741,15 +745,19 @@ static int flexcan_chip_start(struct net_device *dev) * enable tx and rx warning interrupt * enable bus off interrupt * (== FLEXCAN_CTRL_ERR_STATE) - * - * _note_: we enable the "error interrupt" - * (FLEXCAN_CTRL_ERR_MSK), too. Otherwise we don't get any - * warning or bus passive interrupts. */ reg_ctrl = flexcan_read(®s->ctrl); reg_ctrl &= ~FLEXCAN_CTRL_TSYN; reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF | - FLEXCAN_CTRL_ERR_STATE | FLEXCAN_CTRL_ERR_MSK; + FLEXCAN_CTRL_ERR_STATE; + /* + * enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK), + * on most Flexcan cores, too. Otherwise we don't get + * any error warning or passive interrupts. + */ + if (priv->devtype_data->features & FLEXCAN_HAS_BROKEN_ERR_STATE || + priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) + reg_ctrl |= FLEXCAN_CTRL_ERR_MSK; /* save for later use */ priv->reg_ctrl_default = reg_ctrl; @@ -772,7 +780,7 @@ static int flexcan_chip_start(struct net_device *dev) flexcan_write(0x0, ®s->rx14mask); flexcan_write(0x0, ®s->rx15mask); - if (priv->devtype_data->hw_ver >= 10) + if (priv->devtype_data->features & FLEXCAN_HAS_V10_FEATURES) flexcan_write(0x0, ®s->rxfgmask); flexcan_transceiver_switch(priv, 1); @@ -954,6 +962,7 @@ static void __devexit unregister_flexcandev(struct net_device *dev) static const struct of_device_id flexcan_of_match[] = { { .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, }, + { .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, }, { .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, }, { /* sentinel */ }, }; -- cgit v1.2.3-70-g09d2 From bb698ca41ba574b3066ebbc5766e5980ae0051ca Mon Sep 17 00:00:00 2001 From: Wolfgang Grandegger Date: Wed, 10 Oct 2012 21:10:42 +0200 Subject: can: flexcan: disable bus error interrupts for the i.MX6q This patch adds some Flexcan version info and removes the feature flag FLEXCAN_HAS_BROKEN_ERR_STATE for the i.MX6Q. It also has the line [TR]WRN_INT properly connected. Cc: Hui Wang Cc: Shawn Guo Signed-off-by: Wolfgang Grandegger [mkl: convert to incremental patch] Signed-off-by: Marc Kleine-Budde --- drivers/net/can/flexcan.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'drivers/net/can/flexcan.c') diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index c78ecfca1e4..a412bf6d73e 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -144,9 +144,22 @@ #define FLEXCAN_MB_CODE_MASK (0xf0ffffff) -/* FLEXCAN hardware feature flags */ +/* + * FLEXCAN hardware feature flags + * + * Below is some version info we got: + * SOC Version IP-Version Glitch- [TR]WRN_INT + * Filter? connected? + * MX25 FlexCAN2 03.00.00.00 no no + * MX28 FlexCAN2 03.00.04.00 yes yes + * MX35 FlexCAN2 03.00.00.00 no no + * MX53 FlexCAN2 03.00.00.00 yes no + * MX6s FlexCAN3 10.00.12.00 yes yes + * + * Some SOCs do not have the RX_WARN & TX_WARN interrupt line connected. + */ #define FLEXCAN_HAS_V10_FEATURES BIT(1) /* For core version >= 10 */ -#define FLEXCAN_HAS_BROKEN_ERR_STATE BIT(2) /* Broken error state handling */ +#define FLEXCAN_HAS_BROKEN_ERR_STATE BIT(2) /* [TR]WRN_INT not connected */ /* Structure of the message buffer */ struct flexcan_mb { @@ -205,7 +218,7 @@ static struct flexcan_devtype_data fsl_p1010_devtype_data = { }; static struct flexcan_devtype_data fsl_imx28_devtype_data; static struct flexcan_devtype_data fsl_imx6q_devtype_data = { - .features = FLEXCAN_HAS_V10_FEATURES | FLEXCAN_HAS_BROKEN_ERR_STATE, + .features = FLEXCAN_HAS_V10_FEATURES, }; static const struct can_bittiming_const flexcan_bittiming_const = { -- cgit v1.2.3-70-g09d2