[U-Boot] [u-boot][PATCH] ARM: DRA7-evm: prevent DCAN1 _wait_target_disable failure in kernel
If board is booted with transitions happening on DCAN1 pins then the following warning is seen in the kernel at boot when the hwmod layer initializes.
"omap_hwmod: dcan1: _wait_target_disable failed"
This is because DCAN1 module's SWAKEUP mechanism is broken and it fails to correctly turn OFF if it sees a transition on the DCAN1 pins. Suggested workaround is to keep DCAN1 pins in safe mode while enabling/disabling DCAN1 module.
The hwmod layer enables and disables all modules at boot and we have no opportunity to put the DCAN1 pins in safe mode at that point.
DCAN1 is not used by u-boot so it doesn't matter to it if these pins are in safe mode. The kernel driver correctly configures the right mode when DCAN1 is active.
Signed-off-by: Roger Quadros rogerq@ti.com --- board/ti/dra7xx/mux_data.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/board/ti/dra7xx/mux_data.h b/board/ti/dra7xx/mux_data.h index c9301a5..91e00b9 100644 --- a/board/ti/dra7xx/mux_data.h +++ b/board/ti/dra7xx/mux_data.h @@ -358,7 +358,7 @@ const struct pad_conf_entry dra74x_core_padconf_array[] = { {SPI2_D1, (M1 | PIN_INPUT_SLEW)}, /* spi2_d1.uart3_txd */ {SPI2_D0, (M1 | PIN_INPUT_SLEW)}, /* spi2_d0.uart3_ctsn */ {SPI2_CS0, (M1 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* spi2_cs0.uart3_rtsn */ - {DCAN1_TX, (M0 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* dcan1_tx.dcan1_tx */ + {DCAN1_TX, (M15 | PULL_UP)}, /* dcan1_tx.safe for dcan1_tx */ {DCAN1_RX, (M14 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* dcan1_rx.gpio1_15 */ {UART1_RXD, (M0 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* uart1_rxd.uart1_rxd */ {UART1_TXD, (M0 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* uart1_txd.uart1_txd */ @@ -370,7 +370,7 @@ const struct pad_conf_entry dra74x_core_padconf_array[] = { {UART2_RTSN, (M3 | PIN_INPUT_PULLUP)}, /* uart2_rtsn.mmc4_dat3 */ {I2C2_SDA, (M0 | PIN_INPUT_PULLUP)}, /* i2c2_sda.i2c2_sda */ {I2C2_SCL, (M0 | PIN_INPUT_PULLUP)}, /* i2c2_scl.i2c2_scl */ - {WAKEUP0, (M1 | PIN_OUTPUT)}, /* Wakeup0.dcan1_rx */ + {WAKEUP0, (M15 | PULL_UP)}, /* Wakeup0.safe for dcan1_rx */ {WAKEUP2, (M14 | PIN_OUTPUT)}, /* Wakeup2.gpio1_2 */ };
On 06/24/2015 09:00 AM, Roger Quadros wrote:
If board is booted with transitions happening on DCAN1 pins then the following warning is seen in the kernel at boot when the hwmod layer initializes.
"omap_hwmod: dcan1: _wait_target_disable failed"
This is because DCAN1 module's SWAKEUP mechanism is broken and it fails to correctly turn OFF if it sees a transition on the DCAN1 pins. Suggested workaround is to keep DCAN1 pins in safe mode while enabling/disabling DCAN1 module.
The hwmod layer enables and disables all modules at boot and we have no opportunity to put the DCAN1 pins in safe mode at that point.
DCAN1 is not used by u-boot so it doesn't matter to it if these pins are in safe mode. The kernel driver correctly configures the right mode when DCAN1 is active.
Signed-off-by: Roger Quadros rogerq@ti.com
board/ti/dra7xx/mux_data.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/board/ti/dra7xx/mux_data.h b/board/ti/dra7xx/mux_data.h index c9301a5..91e00b9 100644 --- a/board/ti/dra7xx/mux_data.h +++ b/board/ti/dra7xx/mux_data.h @@ -358,7 +358,7 @@ const struct pad_conf_entry dra74x_core_padconf_array[] = { {SPI2_D1, (M1 | PIN_INPUT_SLEW)}, /* spi2_d1.uart3_txd */ {SPI2_D0, (M1 | PIN_INPUT_SLEW)}, /* spi2_d0.uart3_ctsn */ {SPI2_CS0, (M1 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* spi2_cs0.uart3_rtsn */
- {DCAN1_TX, (M0 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* dcan1_tx.dcan1_tx */
- {DCAN1_TX, (M15 | PULL_UP)}, /* dcan1_tx.safe for dcan1_tx */ {DCAN1_RX, (M14 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* dcan1_rx.gpio1_15 */ {UART1_RXD, (M0 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* uart1_rxd.uart1_rxd */ {UART1_TXD, (M0 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* uart1_txd.uart1_txd */
@@ -370,7 +370,7 @@ const struct pad_conf_entry dra74x_core_padconf_array[] = { {UART2_RTSN, (M3 | PIN_INPUT_PULLUP)}, /* uart2_rtsn.mmc4_dat3 */ {I2C2_SDA, (M0 | PIN_INPUT_PULLUP)}, /* i2c2_sda.i2c2_sda */ {I2C2_SCL, (M0 | PIN_INPUT_PULLUP)}, /* i2c2_scl.i2c2_scl */
- {WAKEUP0, (M1 | PIN_OUTPUT)}, /* Wakeup0.dcan1_rx */
- {WAKEUP0, (M15 | PULL_UP)}, /* Wakeup0.safe for dcan1_rx */ {WAKEUP2, (M14 | PIN_OUTPUT)}, /* Wakeup2.gpio1_2 */
};
LGTM, could you also look at x15 platform?
If board is booted with transitions happening on DCAN1 pins then the following warning is seen in the kernel at boot when the hwmod layer initializes.
"omap_hwmod: dcan1: _wait_target_disable failed"
This is because DCAN1 module's SWAKEUP mechanism is broken and it fails to correctly turn OFF if it sees a transition on the DCAN1 pins. Suggested workaround is to keep DCAN1 pins in safe mode while enabling/disabling DCAN1 module.
The hwmod layer enables and disables all modules at boot and we have no opportunity to put the DCAN1 pins in safe mode at that point.
DCAN1 is not used by u-boot so it doesn't matter to it if these pins are in safe mode. The kernel driver correctly configures the right mode when DCAN1 is active.
Signed-off-by: Roger Quadros rogerq@ti.com --- board/ti/beagle_x15/mux_data.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/board/ti/beagle_x15/mux_data.h b/board/ti/beagle_x15/mux_data.h index 09d3650..da2610c 100644 --- a/board/ti/beagle_x15/mux_data.h +++ b/board/ti/beagle_x15/mux_data.h @@ -244,8 +244,8 @@ const struct pad_conf_entry core_padconf_array_essential[] = { {SPI2_D1, (M14 | PIN_INPUT_PULLDOWN)}, /* spi2_d1.gpio7_15 */ {SPI2_D0, (M14 | PIN_INPUT_PULLUP)}, /* spi2_d0.gpio7_16 */ {SPI2_CS0, (M14 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* spi2_cs0.gpio7_17 */ - {DCAN1_TX, (M0 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* dcan1_tx.dcan1_tx */ - {DCAN1_RX, (M0 | PIN_INPUT_PULLUP | SLEWCONTROL)}, /* dcan1_rx.dcan1_rx */ + {DCAN1_TX, (M15 | PULLUP)}, /* dcan1_tx.safe for dcan1_tx */ + {DCAN1_RX, (M15 | PULLUP)}, /* dcan1_rx.safe for dcan1_rx */ {UART1_RXD, (M0 | PIN_INPUT_SLEW)}, /* uart1_rxd.uart1_rxd */ {UART1_TXD, (M0 | PIN_INPUT_SLEW)}, /* uart1_txd.uart1_txd */ {UART1_CTSN, (M15 | PIN_INPUT_PULLDOWN)}, /* uart1_ctsn.Driveroff */
On Thu, Jun 25, 2015 at 10:25:50AM +0300, Roger Quadros wrote:
If board is booted with transitions happening on DCAN1 pins then the following warning is seen in the kernel at boot when the hwmod layer initializes.
"omap_hwmod: dcan1: _wait_target_disable failed"
This is because DCAN1 module's SWAKEUP mechanism is broken and it fails to correctly turn OFF if it sees a transition on the DCAN1 pins. Suggested workaround is to keep DCAN1 pins in safe mode while enabling/disabling DCAN1 module.
The hwmod layer enables and disables all modules at boot and we have no opportunity to put the DCAN1 pins in safe mode at that point.
DCAN1 is not used by u-boot so it doesn't matter to it if these pins are in safe mode. The kernel driver correctly configures the right mode when DCAN1 is active.
Signed-off-by: Roger Quadros rogerq@ti.com
With %s/PULLUP/PULL_UP/ based on the DRA7xx patch, applied to u-boot/master, thanks!
On 10/07/15 15:57, Tom Rini wrote:
On Thu, Jun 25, 2015 at 10:25:50AM +0300, Roger Quadros wrote:
If board is booted with transitions happening on DCAN1 pins then the following warning is seen in the kernel at boot when the hwmod layer initializes.
"omap_hwmod: dcan1: _wait_target_disable failed"
This is because DCAN1 module's SWAKEUP mechanism is broken and it fails to correctly turn OFF if it sees a transition on the DCAN1 pins. Suggested workaround is to keep DCAN1 pins in safe mode while enabling/disabling DCAN1 module.
The hwmod layer enables and disables all modules at boot and we have no opportunity to put the DCAN1 pins in safe mode at that point.
DCAN1 is not used by u-boot so it doesn't matter to it if these pins are in safe mode. The kernel driver correctly configures the right mode when DCAN1 is active.
Signed-off-by: Roger Quadros rogerq@ti.com
With %s/PULLUP/PULL_UP/ based on the DRA7xx patch, applied to u-boot/master, thanks!
Thanks Tom :).
cheers, -roger
On Wed, Jun 24, 2015 at 05:00:11PM +0300, Roger Quadros wrote:
If board is booted with transitions happening on DCAN1 pins then the following warning is seen in the kernel at boot when the hwmod layer initializes.
"omap_hwmod: dcan1: _wait_target_disable failed"
This is because DCAN1 module's SWAKEUP mechanism is broken and it fails to correctly turn OFF if it sees a transition on the DCAN1 pins. Suggested workaround is to keep DCAN1 pins in safe mode while enabling/disabling DCAN1 module.
The hwmod layer enables and disables all modules at boot and we have no opportunity to put the DCAN1 pins in safe mode at that point.
DCAN1 is not used by u-boot so it doesn't matter to it if these pins are in safe mode. The kernel driver correctly configures the right mode when DCAN1 is active.
Signed-off-by: Roger Quadros rogerq@ti.com
Applied to u-boot/master, thanks!
participants (3)
-
Nishanth Menon -
Roger Quadros -
Tom Rini