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2022-10-26tty: xilinx_uartps: Fix the ignore_statusShubhrajyoti Datta1-0/+2
[ Upstream commit b8a6c3b3d4654fba19881cc77da61eac29f57cae ] Currently the ignore_status is not considered in the isr. Add a check to add the ignore_status. Fixes: 61ec9016988f ("tty/serial: add support for Xilinx PS UART") Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Link: https://lore.kernel.org/r/20220729114748.18332-5-shubhrajyoti.datta@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18serial: xilinx_uartps: Fix race condition causing stuck TXAnssi Hannula1-1/+2
[ Upstream commit 88b20f84f0fe47409342669caf3e58a3fc64c316 ] xilinx_uartps .start_tx() clears TXEMPTY when enabling TXEMPTY to avoid any previous TXEVENT event asserting the UART interrupt. This clear operation is done immediately after filling the TX FIFO. However, if the bytes inserted by cdns_uart_handle_tx() are consumed by the UART before the TXEMPTY is cleared, the clear operation eats the new TXEMPTY event as well, causing cdns_uart_isr() to never receive the TXEMPTY event. If there are bytes still queued in circbuf, TX will get stuck as they will never get transferred to FIFO (unless new bytes are queued to circbuf in which case .start_tx() is called again). While the racy missed TXEMPTY occurs fairly often with short data sequences (e.g. write 1 byte), in those cases circbuf is usually empty so no action on TXEMPTY would have been needed anyway. On the other hand, longer data sequences make the race much more unlikely as UART takes longer to consume the TX FIFO. Therefore it is rare for this race to cause visible issues in general. Fix the race by clearing the TXEMPTY bit in ISR *before* filling the FIFO. The TXEMPTY bit in ISR will only get asserted at the exact moment the TX FIFO *becomes* empty, so clearing the bit before filling FIFO does not cause an extra immediate assertion even if the FIFO is initially empty. This is hard to reproduce directly on a normal system, but inserting e.g. udelay(200) after cdns_uart_handle_tx(port), setting 4000000 baud, and then running "dd if=/dev/zero bs=128 of=/dev/ttyPS0 count=50" reliably reproduces the issue on my ZynqMP test system unless this fix is applied. Fixes: 85baf542d54e ("tty: xuartps: support 64 byte FIFO size") Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi> Link: https://lore.kernel.org/r/20211026102741.2910441-1-anssi.hannula@bitwise.fi Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-24treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva1-1/+1
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-07-21tty: xilinx_uartps: Really fix id assignmentHelmut Grohne1-2/+6
The problems started with the revert (18cc7ac8a28e28). The cdns_uart_console.index is statically assigned -1. When the port is registered, Linux assigns consecutive numbers to it. It turned out that when using ttyPS1 as console, the index is not updated as we are reusing the same cdns_uart_console instance for multiple ports. When registering ttyPS0, it gets updated from -1 to 0, but when registering ttyPS1, it already is 0 and not updated. That led to 2ae11c46d5fdc4. It assigns the index prior to registering the uart_driver once. Unfortunately, that ended up breaking the situation where the probe order does not match the id order. When using the same device tree for both uboot and linux, it is important that the serial0 alias points to the console. So some boards reverse those aliases. This was reported by Jan Kiszka. The proposed fix was reverting the index assignment and going back to the previous iteration. However such a reversed assignement (serial0 -> uart1, serial1 -> uart0) was already partially broken by the revert (18cc7ac8a28e28). While the ttyPS device works, the kmsg connection is already broken and kernel messages go missing. Reverting the id assignment does not fix this. >From the xilinx_uartps driver pov (after reverting the refactoring commits), there can be only one console. This manifests in static variables console_pprt and cdns_uart_console. These variables are not properly linked and can go out of sync. The cdns_uart_console.index is important for uart_add_one_port. We call that function for each port - one of which hopefully is the console. If it isn't, the CON_ENABLED flag is not set and console_port is cleared. The next cdns_uart_probe call then tries to register the next port using that same cdns_uart_console. It is important that console_port and cdns_uart_console (and its index in particular) stay in sync. The index assignment implemented by Shubhrajyoti Datta is correct in principle. It just may have to happen a second time if the first cdns_uart_probe call didn't encounter the console device. And we shouldn't change the index once the console uart is registered. Reported-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Reported-by: Jan Kiszka <jan.kiszka@web.de> Link: https://lore.kernel.org/linux-serial/f4092727-d8f5-5f91-2c9f-76643aace993@siemens.com/ Fixes: 18cc7ac8a28e28 ("Revert "serial: uartps: Register own uart console and driver structures"") Fixes: 2ae11c46d5fdc4 ("tty: xilinx_uartps: Fix missing id assignment to the console") Fixes: 76ed2e10579671 ("Revert "tty: xilinx_uartps: Fix missing id assignment to the console"") Signed-off-by: Helmut Grohne <helmut.grohne@intenta.de> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200713073227.GA3805@laureti-dev Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-27Revert "tty: xilinx_uartps: Fix missing id assignment to the console"Jan Kiszka1-1/+0
This reverts commit 2ae11c46d5fdc46cb396e35911c713d271056d35. It turned out to break the ultra96-rev1, e.g., which uses uart1 as serial0 (and stdout-path = "serial0:115200n8"). Fixes: 2ae11c46d5fd ("tty: xilinx_uartps: Fix missing id assignment to the console") Cc: stable <stable@vger.kernel.org> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Michal Simek <michal.simek@xilinx.com> Tested-by: Michal Simek <michal.simek@xilinx.com> Link: https://lore.kernel.org/r/f4092727-d8f5-5f91-2c9f-76643aace993@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-11Merge 5.7-rc5 into tty-nextGreg Kroah-Hartman1-0/+1
We need the tty fixes in here too. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-04tty: xilinx_uartps: Fix missing id assignment to the consoleShubhrajyoti Datta1-0/+1
When serial console has been assigned to ttyPS1 (which is serial1 alias) console index is not updated property and pointing to index -1 (statically initialized) which ends up in situation where nothing has been printed on the port. The commit 18cc7ac8a28e ("Revert "serial: uartps: Register own uart console and driver structures"") didn't contain this line which was removed by accident. Fixes: 18cc7ac8a28e ("Revert "serial: uartps: Register own uart console and driver structures"") Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Link: https://lore.kernel.org/r/ed3111533ef5bd342ee5ec504812240b870f0853.1588602446.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-27Merge 5.7-rc3 into tty-nextGreg Kroah-Hartman1-162/+49
We need the tty/serial fixes in here too. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16serial: uartps: Use cdns_uart_tx_empty in console_writeRaviteja Narayanam1-3/+1
Instead of accessing the registers and checking for tx_empty, use cdns_uart_tx_empty in cdns_uart_console_write function. Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com> Reviewed-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Link: https://lore.kernel.org/r/1586413563-29125-3-git-send-email-raviteja.narayanam@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16serial: uartps: Wait for tx_empty in console setupRaviteja Narayanam1-0/+8
On some platforms, the log is corrupted while console is being registered. It is observed that when set_termios is called, there are still some bytes in the FIFO to be transmitted. So, wait for tx_empty inside cdns_uart_console_setup before calling set_termios. Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com> Reviewed-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Link: https://lore.kernel.org/r/1586413563-29125-2-git-send-email-raviteja.narayanam@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16Revert "serial: uartps: Register own uart console and driver structures"Michal Simek1-55/+40
This reverts commit 024ca329bfb9a948f76eaff3243e21b7e70182f2. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/1ee35667e36a8efddee381df5fe495ad65f4d15c.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16Revert "serial: uartps: Move Port ID to device data structure"Michal Simek1-11/+9
This reverts commit bed25ac0e2b6ab8f9aed2d20bc9c3a2037311800. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/eb0ec98fecdca9b79c1a3ac0c30c668b6973b193.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16Revert "serial: uartps: Change uart ID port allocation"Michal Simek1-98/+13
This reverts commit ae1cca3fa3478be92948dbbcd722390272032ade. With setting up NR_PORTS to 16 to be able to use serial2 and higher aliases and don't loose functionality which was intended by these changes. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/a94931b65ce0089f76fb1fe6b446a08731bff754.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16Revert "serial: uartps: Do not allow use aliases >= MAX_UART_INSTANCES"Michal Simek1-4/+2
This reverts commit 2088cfd882d0403609bdf426e9b24372fe1b8337. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/dac3898e3e32d963f357fb436ac9a7ac3cbcf933.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16Revert "serial: uartps: Fix error path when alloc failed"Michal Simek1-4/+2
This reverts commit 32cf21ac4edd6c0d5b9614368a83bcdc68acb031. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/46cd7f039db847c08baa6508edd7854f7c8ff80f.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16Revert "serial: uartps: Use the same dynamic major number for all ports"Michal Simek1-3/+2
This reverts commit ab262666018de6f4e206b021386b93ed0c164316. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/14a565fc1e14a5ec6cc6a6710deb878ae8305f22.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16Revert "serial: uartps: Fix uartps_major handling"Michal Simek1-7/+1
This reverts commit 5e9bd2d70ae7c00a95a22994abf1eef728649e64. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/310999ab5342f788a7bc1b0e68294d4f052cad07.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: uartps: Add TACTIVE check in cdns_uart_tx_empty functionRaviteja Narayanam1-2/+2
Make sure that all bytes are transmitted out of Uart by monitoring CDNS_UART_SR_TACTIVE bit as well. Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Acked-by: Maarten Brock <m.brock@vanmierlo.com> Link: https://lore.kernel.org/r/e2514818af5973be291cc117d07739f068b71639.1584610774.git.shubhrajyoti.datta@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24serial: uartps: Remove unconditional wait inside set_termiosRaviteja Narayanam1-14/+2
set_termios function should not wait for the transmit FIFO empty (CDNS_UART_SR_TXEMPTY) unconditionally. The tty layer takes care of it based on the parameter passed (TCSANOW/TCSADRAIN/TCSAFLUSH). Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Link: https://lore.kernel.org/r/536e190dd5bbb474007a67e6323c048288942a28.1584610774.git.shubhrajyoti.datta@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14serial: xilinx_uartps: set_mctrl sets RTS and DTRMaarten Brock1-0/+4
set_mctrl now sets RTS and DTR. Signed-off-by: Maarten Brock <m.brock@vanmierlo.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Link: https://lore.kernel.org/r/1574687731-21563-3-git-send-email-shubhrajyoti.datta@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14serial: xilinx_uartps: set_termios sets flowcontrolMaarten Brock1-5/+9
Let set_termios enable/disable automatic flow control. set_mctrl should not touch automatic flow control. Signed-off-by: Maarten Brock <m.brock@vanmierlo.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Link: https://lore.kernel.org/r/1574687731-21563-2-git-send-email-shubhrajyoti.datta@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14serial: xilinx_uartps: Let get_mctrl return statusMaarten Brock1-3/+25
Some of the applications like microcom do not work if modem is disabled. To fix them we always return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR instead of 0 when using cts_override. Make get_mctrl return actual status when not using cts_override. Signed-off-by: Maarten Brock <m.brock@vanmierlo.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Link: https://lore.kernel.org/r/1574687731-21563-1-git-send-email-shubhrajyoti.datta@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-18tty/serial: Migrate xilinx_uartps to use has_sysrqDmitry Safonov1-4/+1
The SUPPORT_SYSRQ ifdeffery is not nice as: - May create misunderstanding about sizeof(struct uart_port) between different objects - Prevents moving functions from serial_core.h - Reduces readability (well, it's ifdeffery - it's hard to follow) In order to remove SUPPORT_SYSRQ, has_sysrq variable has been added. Initialise it in driver's probe and remove ifdeffery. Cc: Michal Simek <michal.simek@xilinx.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Dmitry Safonov <dima@arista.com> Link: https://lore.kernel.org/r/20191213000657.931618-53-dima@arista.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-04serial: uartps: Fix uartps_major handlingMichal Simek1-1/+7
There are two parts which should be fixed. The first one is to assigned uartps_major at the end of probe() to avoid complicated logic when something fails. The second part is initialized uartps_major number to 0 when last device is removed. This will ensure that on next probe driver will ask for new dynamic major number. Fixes: ab262666018d ("serial: uartps: Use the same dynamic major number for all ports") Reported-by: Paul Thomas <pthomas8589@gmail.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Link: https://lore.kernel.org/r/d2652cda992833315c4f96f06953eb547f928918.1570194248.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-04xilinx_uartps.c: suppress "may be used uninitialised" warningStephen Rothwell1-1/+1
A powerpc allyesconfig build produces this warning: In file included from include/linux/radix-tree.h:16, from include/linux/idr.h:15, from include/linux/kernfs.h:13, from include/linux/sysfs.h:16, from include/linux/kobject.h:20, from include/linux/device.h:16, from include/linux/platform_device.h:13, from drivers/tty/serial/xilinx_uartps.c:16: drivers/tty/serial/xilinx_uartps.c: In function 'cdns_uart_console_write': include/linux/spinlock.h:288:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized] _raw_spin_unlock_irqrestore(lock, flags); \ ^~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/tty/serial/xilinx_uartps.c:1197:16: note: 'flags' was declared here unsigned long flags; ^~~~~ It looks like gcc just can't track the relationship between "locked" and "flags", and it is obvious that "flags" won't be used when "locked" is zero, so the simplest thing is to initialise flags. Cc: Jiri Slaby <jslaby@suse.com> Cc: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lore.kernel.org/r/20190731160557.6a09c3e1@canb.auug.org.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-18serial: uartps: Remove useless return from cdns_uart_poll_put_charNava kishore Manne1-2/+0
There is no reason to call return at the end of function which should return void. The patch is also remove one checkpatch warning: WARNING: void function return statements are not generally useful + return; +} Fixes: 6ee04c6c5488 ("tty: xuartps: Add polled mode support for xuartps") Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-18serial: uartps: Do not add a trailing semicolon to macroNava kishore Manne1-1/+1
This patch fixes this checkpatch warning: WARNING: macros should not use a trailing semicolon +#define to_cdns_uart(_nb) container_of(_nb, struct cdns_uart, \ + clk_rate_change_nb); Fixes: d9bb3fb12685 ("tty: xuartps: Rebrand driver as Cadence UART") Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-18serial: uartps: Fix long line over 80 charsNava kishore Manne1-1/+2
Trivial patch which fixes one checkpatch warning: WARNING: line over 80 characters + !(readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_TXFULL)) { Fixes: c8dbdc842d30 ("serial: xuartps: Rewrite the interrupt handling logic") Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-18serial: uartps: Fix multiple line dereferenceNava kishore Manne1-2/+2
Trivial patch which fixes this checkpatch warning: WARNING: Avoid multiple line dereference - prefer 'port->state->xmit.tail' + port->state->xmit.buf[port->state->xmit. + tail], port->membase + CDNS_UART_FIFO); Fixes: c8dbdc842d30 ("serial: xuartps: Rewrite the interrupt handling logic") Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-18serial: uartps: Use octal permission for module_param()Nava kishore Manne1-2/+2
Octal permission is preffered compare to symbolic one. This patch fixes checkpatch warnings: Symbolic permissions 'S_IRUGO' are not preferred. Consider using octal permissions '0444'. Fixes: 85baf542d54e ("tty: xuartps: support 64 byte FIFO size") Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-18serial: uartps: Use the same dynamic major number for all portsShubhrajyoti Datta1-2/+3
Let kernel to find out major number dynamically for the first device and then reuse it for other instances. This fixes the issue that each uart is registered with a different major number. After the patch: crw------- 1 root root 253, 0 Jun 10 08:31 /dev/ttyPS0 crw--w---- 1 root root 253, 1 Jan 1 1970 /dev/ttyPS1 Fixes: 024ca329bfb9 ("serial: uartps: Register own uart console and driver structures") Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-10serial: uartps: Add a timeout to the tx empty waitShubhrajyoti Datta1-4/+10
In case the cable is not connected then the target gets into an infinite wait for tx empty. Add a timeout to the tx empty wait. Reported-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-10serial: uartps: Move the spinlock after the read of the tx emptyShubhrajyoti Datta1-2/+1
Currently we are doing a read of the status register. Move the spinlock after that as the reads need not be spinlock protected. This patch prevents relaxing the cpu with spinlock held. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-29serial: uartps: Add support for cts-overrideShubhrajyoti Datta1-0/+12
Having flow is configurable. Add support for the same by checking for cts-override. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-01tty: xilinx_uartps: Correct return value in probeRajan Vaja1-13/+19
Existing driver checks for alternate clock if devm_clk_get() fails and returns error code for last clock failure. If xilinx_uartps is called before clock driver, devm_clk_get() returns -EPROBE_DEFER. In this case, probe should not check for alternate clock as main clock is already present in DTS and return -EPROBE_DEFER only. This patch fixes it by not checking for alternate clock when main clock get returns -EPROBE_DEFER. Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-19serial: uartps: Fix stuck ISR if RX disabled with non-empty FIFOAnssi Hannula1-1/+7
If RX is disabled while there are still unprocessed bytes in RX FIFO, cdns_uart_handle_rx() called from interrupt handler will get stuck in the receive loop as read bytes will not get removed from the RX FIFO and CDNS_UART_SR_RXEMPTY bit will never get set. Avoid the stuck handler by checking first if RX is disabled. port->lock protects against race with RX-disabling functions. This HW behavior was mentioned by Nathan Rossi in 43e98facc4a3 ("tty: xuartps: Fix RX hang, and TX corruption in termios call") which fixed a similar issue in cdns_uart_set_termios(). The behavior can also be easily verified by e.g. setting CDNS_UART_CR_RX_DIS at the beginning of cdns_uart_handle_rx() - the following loop will then get stuck. Resetting the FIFO using RXRST would not set RXEMPTY either so simply issuing a reset after RX-disable would not work. I observe this frequently on a ZynqMP board during heavy RX load at 1M baudrate when the reader process exits and thus RX gets disabled. Fixes: 61ec9016988f ("tty/serial: add support for Xilinx PS UART") Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19serial: uartps: Fix interrupt mask issue to handle the RX interrupts properlyNava kishore Manne1-2/+2
This patch Correct the RX interrupt mask value to handle the RX interrupts properly. Fixes: c8dbdc842d30 ("serial: xuartps: Rewrite the interrupt handling logic") Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19serial: uartps: Fix error path when alloc failedMichal Simek1-2/+4
When cdns_uart_console allocation failed there is a need to also clear ID from ID list. Fixes: ae1cca3fa347 ("serial: uartps: Change uart ID port allocation") Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19serial: uartps: Check if the device is a consoleShubhrajyoti Datta1-2/+2
While checking for console_suspend_enabled also check if the device is a console. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19serial: uartps: Add the device_init_wakeupShubhrajyoti Datta1-0/+2
Initialise the device wakeup. The device_init_wakeup is needed for the wakeup to work by default. Uart can be configured as the primary wakeup source so it is good to enable wakeup by default. The same functionality is enabled also by 8250_omap, atmel_serial, omap-serial and stm32-usart. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-06Revert "tty: xilinx_uartps: Correct return value in probe"Greg Kroah-Hartman1-12/+14
This reverts commit eca42d4cf3c591c36312c52707e0a712e0c7256a. During review it was rejected, so drop it from the tree. Cc: Rajan Vaja <RAJANV@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05tty: xilinx_uartps: Correct return value in probeRajan Vaja1-14/+12
Existing driver checks for alternate clock if devm_clk_get() fails and returns error code for last clock failure. If xilinx_uartps is called before clock driver, devm_clk_get() returns -EPROBE_DEFER. In this case, probe should not check for alternate clock as main clock is already present in DTS and return -EPROBE_DEFER only. This patch fixes it by not checking for alternate clock when main clock get returns -EPROBE_DEFER. Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-09serial: set suppress_bind_attrs flag only if builtinAnders Roxell1-0/+1
When the test 'CONFIG_DEBUG_TEST_DRIVER_REMOVE=y' is enabled, arch_initcall(pl011_init) came before subsys_initcall(default_bdi_init). devtmpfs gets killed because we try to remove a file and decrement the wb reference count before the noop_backing_device_info gets initialized. [ 0.332075] Serial: AMBA PL011 UART driver [ 0.485276] 9000000.pl011: ttyAMA0 at MMIO 0x9000000 (irq = 39, base_baud = 0) is a PL011 rev1 [ 0.502382] console [ttyAMA0] enabled [ 0.515710] Unable to handle kernel paging request at virtual address 0000800074c12000 [ 0.516053] Mem abort info: [ 0.516222] ESR = 0x96000004 [ 0.516417] Exception class = DABT (current EL), IL = 32 bits [ 0.516641] SET = 0, FnV = 0 [ 0.516826] EA = 0, S1PTW = 0 [ 0.516984] Data abort info: [ 0.517149] ISV = 0, ISS = 0x00000004 [ 0.517339] CM = 0, WnR = 0 [ 0.517553] [0000800074c12000] user address but active_mm is swapper [ 0.517928] Internal error: Oops: 96000004 [#1] PREEMPT SMP [ 0.518305] Modules linked in: [ 0.518839] CPU: 0 PID: 13 Comm: kdevtmpfs Not tainted 4.19.0-rc5-next-20180928-00002-g2ba39ab0cd01-dirty #82 [ 0.519307] Hardware name: linux,dummy-virt (DT) [ 0.519681] pstate: 80000005 (Nzcv daif -PAN -UAO) [ 0.519959] pc : __destroy_inode+0x94/0x2a8 [ 0.520212] lr : __destroy_inode+0x78/0x2a8 [ 0.520401] sp : ffff0000098c3b20 [ 0.520590] x29: ffff0000098c3b20 x28: 00000000087a3714 [ 0.520904] x27: 0000000000002000 x26: 0000000000002000 [ 0.521179] x25: ffff000009583000 x24: 0000000000000000 [ 0.521467] x23: ffff80007bb52000 x22: ffff80007bbaa7c0 [ 0.521737] x21: ffff0000093f9338 x20: 0000000000000000 [ 0.522033] x19: ffff80007bbb05d8 x18: 0000000000000400 [ 0.522376] x17: 0000000000000000 x16: 0000000000000000 [ 0.522727] x15: 0000000000000400 x14: 0000000000000400 [ 0.523068] x13: 0000000000000001 x12: 0000000000000001 [ 0.523421] x11: 0000000000000000 x10: 0000000000000970 [ 0.523749] x9 : ffff0000098c3a60 x8 : ffff80007bbab190 [ 0.524017] x7 : ffff80007bbaa880 x6 : 0000000000000c88 [ 0.524305] x5 : ffff0000093d96c8 x4 : 61c8864680b583eb [ 0.524567] x3 : ffff0000093d6180 x2 : ffffffffffffffff [ 0.524872] x1 : 0000800074c12000 x0 : 0000800074c12000 [ 0.525207] Process kdevtmpfs (pid: 13, stack limit = 0x(____ptrval____)) [ 0.525529] Call trace: [ 0.525806] __destroy_inode+0x94/0x2a8 [ 0.526108] destroy_inode+0x34/0x88 [ 0.526370] evict+0x144/0x1c8 [ 0.526636] iput+0x184/0x230 [ 0.526871] dentry_unlink_inode+0x118/0x130 [ 0.527152] d_delete+0xd8/0xe0 [ 0.527420] vfs_unlink+0x240/0x270 [ 0.527665] handle_remove+0x1d8/0x330 [ 0.527875] devtmpfsd+0x138/0x1c8 [ 0.528085] kthread+0x14c/0x158 [ 0.528291] ret_from_fork+0x10/0x18 [ 0.528720] Code: 92800002 aa1403e0 d538d081 8b010000 (c85f7c04) [ 0.529367] ---[ end trace 5a3dee47727f877c ]--- Rework to set suppress_bind_attrs flag to avoid removing the device when CONFIG_DEBUG_TEST_DRIVER_REMOVE=y. This applies for pic32_uart and xilinx_uartps as well. Co-developed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-15of: base: Change logic in of_alias_get_alias_list()Michal Simek1-1/+1
Check compatible string first before setting up bit in bitmap to also cover cases that allocated bitfield is not big enough. Show warning about it but let driver to continue to work with allocated bitfield to keep at least some devices (included console which is commonly close to serial0) to work. Fixes: b1078c355d76 ("of: base: Introduce of_alias_get_alias_list() to check alias IDs") Fixes: ae1cca3fa347 ("serial: uartps: Change uart ID port allocation") Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11serial: uartps: Do not allow use aliases >= MAX_UART_INSTANCESMichal Simek1-2/+4
Aliases >= MAX_UART_INSTANCES is no problem to find out and use but in error path is necessary skip clearing bits in bitmap to ensure that only bits in allocated bitmap are handled and nothing beyond that. Without this patch when for example serial90 alias is used then in error patch bit 90 is clear in 32bit wide bitmap. Fixes: ae1cca3fa347 ("serial: uartps: Change uart ID port allocation") Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02serial: uartps: Fix missing unlock on error in cdns_get_id()Wei Yongjun1-1/+3
Add the missing unlock before return from function cdns_get_id() in the error handling case. Fixes: ae1cca3fa347 ("serial: uartps: Change uart ID port allocation") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Reviewed-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20serial: uartps: Change uart ID port allocationMichal Simek1-13/+96
For IPs which have alias algorightm all the time using that alias and minor number. It means serial20 alias ends up as ttyPS20. If alias is not setup for probed IP instance the first unused position is used but that needs to be checked if it is really empty because another instance doesn't need to be probed at that time. of_alias_get_alias_list() fills alias bitmap which exactly shows which ID is free. If alias pointing to different not compatible IP, it is free to use. cdns_get_id() call is placed below structure allocation to simplify error path. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18serial: uartps: Enable automatic flow controlMichal Simek1-5/+4
Enable automatic flow control which should ensure that there is no mainteinance in connection for zcu100 BT case. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Acked-by: Nava kishore Manne <navam@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18serial: uartps: Move Port ID to device data structureMichal Simek1-9/+11
Record port ID in device data structure to be have it connected to certain instance. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18serial: uartps: Register own uart console and driver structuresMichal Simek1-38/+55
Every instance is registering own struct console and struct uart_driver with minor number which corresponds to alias ID (or 0 now) and with 1 uart port. The same alias ID is saved to tty_driver->name_base which is key field for creating ttyPSX name. Because name_base and minor number are setup already there is no need to setup any port->line number because 0 is the right value. Unfortunately this driver is setting up major number to 0 for using dynamic assignment and kernel is allocating different major numbers for every instance instead of using the same major and different minor number. ~# ls -la /dev/ttyPS* crw------- 1 root root 252, 0 Jan 1 03:36 /dev/ttyPS0 crw--w---- 1 root root 253, 1 Jan 1 00:00 /dev/ttyPS1 When major number is not 0. For example 252 then major/minor combinations are in expected form ~# ls -la /dev/ttyPS* crw------- 1 root root 252, 0 Jan 1 04:04 /dev/ttyPS0 crw--w---- 1 root root 252, 1 Jan 1 00:00 /dev/ttyPS1 Driver is not freeing struct cdns_uart_console in case that instance is not used as console. The reason is that console is incorrectly unregistred and "console [0] disabled" message will be shown. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>