From: Randy Dunlap <hidden> Date: 2023-07-24 06:33:54
Reconcile devices.txt with serial/ucc_uart.c regarding device number
assignments. ucc_uart.c supports 4 ports and uses minor devnums
46-49, so update devices.txt with that info.
Then update ucc_uart.c's reference to the location of the devices.txt
list in the kernel source tree.
Fixes: d7584ed2b994 ("[POWERPC] qe-uart: add support for Freescale QUICCEngine UART")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap <redacted>
Cc: Timur Tabi <timur@kernel.org>
Cc: Kumar Gala <redacted>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-serial@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
---
Documentation/admin-guide/devices.txt | 2 +-
drivers/tty/serial/ucc_uart.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff -- a/drivers/tty/serial/ucc_uart.c b/drivers/tty/serial/ucc_uart.c
@@ -59,7 +59,7 @@ static int firmware_loaded;/* #define LOOPBACK *//* The major and minor device numbers are defined in-*http://www.lanana.org/docs/device-list/devices-2.6+.txt. For the QE+*Documentation/admin-guide/devices.txt.FortheQE*UART,wehavemajornumber204andminornumbers46-49,whicharethe*sameasfortheCPM2.ThisdecisionwasmadebecausenoFreescalepart*hasbothaCPMandaQE.
On Sun, Jul 23, 2023 at 11:33:41PM -0700, Randy Dunlap wrote:
Reconcile devices.txt with serial/ucc_uart.c regarding device number
assignments. ucc_uart.c supports 4 ports and uses minor devnums
46-49, so update devices.txt with that info.
Then update ucc_uart.c's reference to the location of the devices.txt
list in the kernel source tree.
Fixes: d7584ed2b994 ("[POWERPC] qe-uart: add support for Freescale QUICCEngine UART")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap <redacted>
Cc: Timur Tabi <timur@kernel.org>
Cc: Kumar Gala <redacted>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-serial@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
---
Documentation/admin-guide/devices.txt | 2 +-
drivers/tty/serial/ucc_uart.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
Very nice, thanks for catching this, I'll go queue it up.
Actually, how did you notice this? I don't think the devices.txt file
is up to date at all anymore, and odds are, other things are wrong in it
too.
thanks,
greg k-h
From: Randy Dunlap <hidden> Date: 2023-07-25 17:32:22
On 7/25/23 10:27, Greg Kroah-Hartman wrote:
On Sun, Jul 23, 2023 at 11:33:41PM -0700, Randy Dunlap wrote:
quoted
Reconcile devices.txt with serial/ucc_uart.c regarding device number
assignments. ucc_uart.c supports 4 ports and uses minor devnums
46-49, so update devices.txt with that info.
Then update ucc_uart.c's reference to the location of the devices.txt
list in the kernel source tree.
Fixes: d7584ed2b994 ("[POWERPC] qe-uart: add support for Freescale QUICCEngine UART")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap <redacted>
Cc: Timur Tabi <timur@kernel.org>
Cc: Kumar Gala <redacted>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-serial@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
---
Documentation/admin-guide/devices.txt | 2 +-
drivers/tty/serial/ucc_uart.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
Very nice, thanks for catching this, I'll go queue it up.
Actually, how did you notice this? I don't think the devices.txt file
is up to date at all anymore, and odds are, other things are wrong in it
too.
I accidentally! saw some reference to lanana.org in the kernel source code
and just grepped for that and saw this...
--
~Randy
From: Timur Tabi <timur@kernel.org> Date: 2023-07-25 20:40:32
On Mon, Jul 24, 2023 at 1:33 AM Randy Dunlap [off-list ref] wrote:
Reconcile devices.txt with serial/ucc_uart.c regarding device number
assignments. ucc_uart.c supports 4 ports and uses minor devnums
46-49, so update devices.txt with that info.
Then update ucc_uart.c's reference to the location of the devices.txt
list in the kernel source tree.
Fixes: d7584ed2b994 ("[POWERPC] qe-uart: add support for Freescale QUICCEngine UART")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap <redacted>
Cc: Timur Tabi <timur@kernel.org>
Cc: Kumar Gala <redacted>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-serial@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Acked-by: Timur Tabi <timur@kernel.org>
One thing does concern me. The UCC UART driver piggy-backs on the CPM
driver's layout (see cpm_uart.h), but apparently CPM UART supports 6
devices, not four:
#define UART_NR fs_uart_nr
where fs_uart_nr is defined in enum fs_uart_id.
Unfortunately, it's been so long since I've touched this code, I'm not
sure whether this means anything.
From: Randy Dunlap <hidden> Date: 2023-07-25 20:51:45
On 7/25/23 13:38, Timur Tabi wrote:
On Mon, Jul 24, 2023 at 1:33 AM Randy Dunlap [off-list ref] wrote:
quoted
Reconcile devices.txt with serial/ucc_uart.c regarding device number
assignments. ucc_uart.c supports 4 ports and uses minor devnums
46-49, so update devices.txt with that info.
Then update ucc_uart.c's reference to the location of the devices.txt
list in the kernel source tree.
Fixes: d7584ed2b994 ("[POWERPC] qe-uart: add support for Freescale QUICCEngine UART")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap <redacted>
Cc: Timur Tabi <timur@kernel.org>
Cc: Kumar Gala <redacted>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-serial@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Acked-by: Timur Tabi <timur@kernel.org>
One thing does concern me. The UCC UART driver piggy-backs on the CPM
driver's layout (see cpm_uart.h), but apparently CPM UART supports 6
devices, not four:
#define UART_NR fs_uart_nr
where fs_uart_nr is defined in enum fs_uart_id.
Unfortunately, it's been so long since I've touched this code, I'm not
sure whether this means anything.
If CPM UART code ever worked with > 4 ports, it probably just used minor devnums
that were not allocated to it.
Also, it looks like the CPU UART part of Documentation/admin-guide/devices.txt
needs to be updated:
46 = /dev/cucpm0 Callout device for ttyCPM0
...
49 = /dev/cucpm5 Callout device for ttyCPM5
The driver must use some tricks to get 6 ports into 4 devnums. :)
--
~Randy
Reconcile devices.txt with serial/ucc_uart.c regarding device number
assignments. ucc_uart.c supports 4 ports and uses minor devnums
46-49, so update devices.txt with that info.
Then update ucc_uart.c's reference to the location of the devices.txt
list in the kernel source tree.
Devices ttyCPM* belong to cpm_uart driver. As explained in the comment
you have modified in UCC uart driver, UCC uart borrows those devices and
shall not be considered as the reference. But the lines you modify in
device.txt doesn't mention QE UCC, it mentions CPM SCC and CPM SMC.
CPM uart driver supports up to 6 ports (4 SCC and 2 SMC).
On one of my boards which has a powerpc mpc866 CPU, I have:
[ 2.393872] ff000a80.serial: ttyCPM0 at MMIO 0xfff00a80 (irq = 19,
base_baud = 8250000) is a CPM UART
[ 2.411899] ff000a90.serial: ttyCPM1 at MMIO 0xfff00a90 (irq = 20,
base_baud = 8250000) is a CPM UART
[ 2.430352] ff000a00.serial: ttyCPM2 at MMIO 0xfff00a00 (irq = 30,
base_baud = 8250000) is a CPM UART
[ 2.448944] ff000a20.serial: ttyCPM3 at MMIO 0xfff00a20 (irq = 29,
base_baud = 8250000) is a CPM UART
[ 2.467435] ff000a40.serial: ttyCPM4 at MMIO 0xfff00a40 (irq = 28,
base_baud = 8250000) is a CPM UART
[ 2.485924] ff000a60.serial: ttyCPM5 at MMIO 0xfff00a60 (irq = 27,
base_baud = 8250000) is a CPM UART
# ll /dev/ttyCPM*
crw------- 1 root root 204, 46 Jan 1 01:01 /dev/ttyCPM0
crw------- 1 root root 204, 47 Jan 1 01:00 /dev/ttyCPM1
crw------- 1 root root 204, 48 Jan 1 01:00 /dev/ttyCPM2
crw------- 1 root root 204, 49 Jan 1 01:00 /dev/ttyCPM3
crw------- 1 root root 204, 50 Jan 1 01:00 /dev/ttyCPM4
crw------- 1 root root 204, 51 Jan 1 01:00 /dev/ttyCPM5
# cat /proc/tty/drivers
/dev/tty /dev/tty 5 0 system:/dev/tty
/dev/console /dev/console 5 1 system:console
/dev/ptmx /dev/ptmx 5 2 system
ttyCPM /dev/ttyCPM 204 46-51 serial
pty_slave /dev/pts 136 0-1048575 pty:slave
pty_master /dev/ptm 128 0-1048575 pty:master
pty_slave /dev/ttyp 3 0-4 pty:slave
pty_master /dev/pty 2 0-4 pty:master
Christophe
quoted hunk
Fixes: d7584ed2b994 ("[POWERPC] qe-uart: add support for Freescale QUICCEngine UART")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap <redacted>
Cc: Timur Tabi <timur@kernel.org>
Cc: Kumar Gala <redacted>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-serial@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
---
Documentation/admin-guide/devices.txt | 2 +-
drivers/tty/serial/ucc_uart.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff -- a/drivers/tty/serial/ucc_uart.c b/drivers/tty/serial/ucc_uart.c
@@ -59,7 +59,7 @@ static int firmware_loaded;/* #define LOOPBACK *//* The major and minor device numbers are defined in-*http://www.lanana.org/docs/device-list/devices-2.6+.txt. For the QE+*Documentation/admin-guide/devices.txt.FortheQE*UART,wehavemajornumber204andminornumbers46-49,whicharethe*sameasfortheCPM2.ThisdecisionwasmadebecausenoFreescalepart*hasbothaCPMandaQE.
From: Randy Dunlap <hidden> Date: 2023-08-01 05:31:59
Hi Christophe,
On 7/31/23 22:21, Christophe Leroy wrote:
Le 24/07/2023 à 08:33, Randy Dunlap a écrit :
quoted
Reconcile devices.txt with serial/ucc_uart.c regarding device number
assignments. ucc_uart.c supports 4 ports and uses minor devnums
46-49, so update devices.txt with that info.
Then update ucc_uart.c's reference to the location of the devices.txt
list in the kernel source tree.
Devices ttyCPM* belong to cpm_uart driver. As explained in the comment
you have modified in UCC uart driver, UCC uart borrows those devices and
shall not be considered as the reference. But the lines you modify in
device.txt doesn't mention QE UCC, it mentions CPM SCC and CPM SMC.
CPM uart driver supports up to 6 ports (4 SCC and 2 SMC).
Thank you for replying.
Does this mean that the patch should be reverted?
On one of my boards which has a powerpc mpc866 CPU, I have:
[ 2.393872] ff000a80.serial: ttyCPM0 at MMIO 0xfff00a80 (irq = 19,
base_baud = 8250000) is a CPM UART
[ 2.411899] ff000a90.serial: ttyCPM1 at MMIO 0xfff00a90 (irq = 20,
base_baud = 8250000) is a CPM UART
[ 2.430352] ff000a00.serial: ttyCPM2 at MMIO 0xfff00a00 (irq = 30,
base_baud = 8250000) is a CPM UART
[ 2.448944] ff000a20.serial: ttyCPM3 at MMIO 0xfff00a20 (irq = 29,
base_baud = 8250000) is a CPM UART
[ 2.467435] ff000a40.serial: ttyCPM4 at MMIO 0xfff00a40 (irq = 28,
base_baud = 8250000) is a CPM UART
[ 2.485924] ff000a60.serial: ttyCPM5 at MMIO 0xfff00a60 (irq = 27,
base_baud = 8250000) is a CPM UART
# ll /dev/ttyCPM*
crw------- 1 root root 204, 46 Jan 1 01:01 /dev/ttyCPM0
crw------- 1 root root 204, 47 Jan 1 01:00 /dev/ttyCPM1
crw------- 1 root root 204, 48 Jan 1 01:00 /dev/ttyCPM2
crw------- 1 root root 204, 49 Jan 1 01:00 /dev/ttyCPM3
crw------- 1 root root 204, 50 Jan 1 01:00 /dev/ttyCPM4
crw------- 1 root root 204, 51 Jan 1 01:00 /dev/ttyCPM5
I don't see minors 50-51 allocated in devices.txt for use by this device/driver.
Am I overlooking that allocation somewhere?
Thanks for your help.
@@ -59,7 +59,7 @@ static int firmware_loaded;/* #define LOOPBACK *//* The major and minor device numbers are defined in-*http://www.lanana.org/docs/device-list/devices-2.6+.txt. For the QE+*Documentation/admin-guide/devices.txt.FortheQE*UART,wehavemajornumber204andminornumbers46-49,whicharethe*sameasfortheCPM2.ThisdecisionwasmadebecausenoFreescalepart*hasbothaCPMandaQE.
Hi Christophe,
On 7/31/23 22:21, Christophe Leroy wrote:
quoted
Le 24/07/2023 à 08:33, Randy Dunlap a écrit :
quoted
Reconcile devices.txt with serial/ucc_uart.c regarding device number
assignments. ucc_uart.c supports 4 ports and uses minor devnums
46-49, so update devices.txt with that info.
Then update ucc_uart.c's reference to the location of the devices.txt
list in the kernel source tree.
Devices ttyCPM* belong to cpm_uart driver. As explained in the comment
you have modified in UCC uart driver, UCC uart borrows those devices and
shall not be considered as the reference. But the lines you modify in
device.txt doesn't mention QE UCC, it mentions CPM SCC and CPM SMC.
CPM uart driver supports up to 6 ports (4 SCC and 2 SMC).
Thank you for replying.
Does this mean that the patch should be reverted?
Not sure it should be reverted, the best would be to fix it up because
anyway what we had was wrong.
See below.
quoted
On one of my boards which has a powerpc mpc866 CPU, I have:
[ 2.393872] ff000a80.serial: ttyCPM0 at MMIO 0xfff00a80 (irq = 19,
base_baud = 8250000) is a CPM UART
[ 2.411899] ff000a90.serial: ttyCPM1 at MMIO 0xfff00a90 (irq = 20,
base_baud = 8250000) is a CPM UART
[ 2.430352] ff000a00.serial: ttyCPM2 at MMIO 0xfff00a00 (irq = 30,
base_baud = 8250000) is a CPM UART
[ 2.448944] ff000a20.serial: ttyCPM3 at MMIO 0xfff00a20 (irq = 29,
base_baud = 8250000) is a CPM UART
[ 2.467435] ff000a40.serial: ttyCPM4 at MMIO 0xfff00a40 (irq = 28,
base_baud = 8250000) is a CPM UART
[ 2.485924] ff000a60.serial: ttyCPM5 at MMIO 0xfff00a60 (irq = 27,
base_baud = 8250000) is a CPM UART
# ll /dev/ttyCPM*
crw------- 1 root root 204, 46 Jan 1 01:01 /dev/ttyCPM0
crw------- 1 root root 204, 47 Jan 1 01:00 /dev/ttyCPM1
crw------- 1 root root 204, 48 Jan 1 01:00 /dev/ttyCPM2
crw------- 1 root root 204, 49 Jan 1 01:00 /dev/ttyCPM3
crw------- 1 root root 204, 50 Jan 1 01:00 /dev/ttyCPM4
crw------- 1 root root 204, 51 Jan 1 01:00 /dev/ttyCPM5
I don't see minors 50-51 allocated in devices.txt for use by this device/driver.
Am I overlooking that allocation somewhere?
I looked into history.
ttyCPM do not appear in devices.txt in v2.6.9.
It was introduced in v2.6.10 as :
46 = /dev/ttyCPM0 PPC CPM (SCC or SMC) - port 0
...
49 = /dev/ttyCPM5 PPC CPM (SCC or SMC) - port 5
Then in v2.6.11 we find:
46 = /dev/ttyCPM0 PPC CPM (SCC or SMC) - port 0
...
47 = /dev/ttyCPM5 PPC CPM (SCC or SMC) - port 5
50 = /dev/ttyIOC40 Altix serial card
...
81 = /dev/ttyIOC431 Altix serial card
So it looks like from the begining the intention was to have 6 ports
(from 0 to 5) and it should have been up to 51. For some reason it was
messed up.
If you look into v2.6.10 drivers/serial/cpm_uart/cpm_uart.h you see
there are 6 ports. Even in v2.6.9 that driver exists and has 6 ports.
Anyway, the ttyIOC* were removed by commit a017ef17cfd8 ("tty/serial:
remove the ioc4_serial driver"), so it should be no problem to fix
devices.txt and set ttyCPM from 46 to 51.
Christophe
@@ -59,7 +59,7 @@ static int firmware_loaded;/* #define LOOPBACK *//* The major and minor device numbers are defined in-*http://www.lanana.org/docs/device-list/devices-2.6+.txt. For the QE+*Documentation/admin-guide/devices.txt.FortheQE*UART,wehavemajornumber204andminornumbers46-49,whicharethe*sameasfortheCPM2.ThisdecisionwasmadebecausenoFreescalepart*hasbothaCPMandaQE.