linux/drivers/tty/serial/Kconfig

1625 lines
51 KiB

tty: serial: add driver for the SiFive UART Add a serial driver for the SiFive UART, found on SiFive FU540 devices (among others). The underlying serial IP block is relatively basic, and currently does not support serial break detection. Further information on the IP block can be found in the documentation and Chisel sources: https://static.dev.sifive.com/FU540-C000-v1.0.pdf https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart This driver was written in collaboration with Wesley Terpstra <wesley@sifive.com>. Tested on a SiFive HiFive Unleashed A00 board, using BBL and the open- source FSBL (using a DT file based on what's targeted for mainline). This revision incorporates changes based on comments by Julia Lawall <julia.lawall@lip6.fr>, Emil Renner Berthing <kernel@esmil.dk>, and Andreas Schwab <schwab@suse.de>. Thanks also to Andreas for testing the driver with his userspace and reporting a bug with the set_termios implementation. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Wesley Terpstra <wesley@sifive.com> Cc: linux-serial@vger.kernel.org Cc: linux-riscv@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: Julia Lawall <julia.lawall@lip6.fr> Cc: Emil Renner Berthing <kernel@esmil.dk> Cc: Andreas Schwab <schwab@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-12 19:01:13 -07:00
tty: serial: add driver for the SiFive UART Add a serial driver for the SiFive UART, found on SiFive FU540 devices (among others). The underlying serial IP block is relatively basic, and currently does not support serial break detection. Further information on the IP block can be found in the documentation and Chisel sources: https://static.dev.sifive.com/FU540-C000-v1.0.pdf https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart This driver was written in collaboration with Wesley Terpstra <wesley@sifive.com>. Tested on a SiFive HiFive Unleashed A00 board, using BBL and the open- source FSBL (using a DT file based on what's targeted for mainline). This revision incorporates changes based on comments by Julia Lawall <julia.lawall@lip6.fr>, Emil Renner Berthing <kernel@esmil.dk>, and Andreas Schwab <schwab@suse.de>. Thanks also to Andreas for testing the driver with his userspace and reporting a bug with the set_termios implementation. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Wesley Terpstra <wesley@sifive.com> Cc: linux-serial@vger.kernel.org Cc: linux-riscv@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: Julia Lawall <julia.lawall@lip6.fr> Cc: Emil Renner Berthing <kernel@esmil.dk> Cc: Andreas Schwab <schwab@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-12 19:01:13 -07:00
tty: serial: add driver for the SiFive UART Add a serial driver for the SiFive UART, found on SiFive FU540 devices (among others). The underlying serial IP block is relatively basic, and currently does not support serial break detection. Further information on the IP block can be found in the documentation and Chisel sources: https://static.dev.sifive.com/FU540-C000-v1.0.pdf https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart This driver was written in collaboration with Wesley Terpstra <wesley@sifive.com>. Tested on a SiFive HiFive Unleashed A00 board, using BBL and the open- source FSBL (using a DT file based on what's targeted for mainline). This revision incorporates changes based on comments by Julia Lawall <julia.lawall@lip6.fr>, Emil Renner Berthing <kernel@esmil.dk>, and Andreas Schwab <schwab@suse.de>. Thanks also to Andreas for testing the driver with his userspace and reporting a bug with the set_termios implementation. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Wesley Terpstra <wesley@sifive.com> Cc: linux-serial@vger.kernel.org Cc: linux-riscv@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: Julia Lawall <julia.lawall@lip6.fr> Cc: Emil Renner Berthing <kernel@esmil.dk> Cc: Andreas Schwab <schwab@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-12 19:01:13 -07:00
tty: serial: add driver for the SiFive UART Add a serial driver for the SiFive UART, found on SiFive FU540 devices (among others). The underlying serial IP block is relatively basic, and currently does not support serial break detection. Further information on the IP block can be found in the documentation and Chisel sources: https://static.dev.sifive.com/FU540-C000-v1.0.pdf https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart This driver was written in collaboration with Wesley Terpstra <wesley@sifive.com>. Tested on a SiFive HiFive Unleashed A00 board, using BBL and the open- source FSBL (using a DT file based on what's targeted for mainline). This revision incorporates changes based on comments by Julia Lawall <julia.lawall@lip6.fr>, Emil Renner Berthing <kernel@esmil.dk>, and Andreas Schwab <schwab@suse.de>. Thanks also to Andreas for testing the driver with his userspace and reporting a bug with the set_termios implementation. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Wesley Terpstra <wesley@sifive.com> Cc: linux-serial@vger.kernel.org Cc: linux-riscv@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: Julia Lawall <julia.lawall@lip6.fr> Cc: Emil Renner Berthing <kernel@esmil.dk> Cc: Andreas Schwab <schwab@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-12 19:01:13 -07:00
tty: serial: Add linflexuart driver for S32V234 Introduce support for LINFlex driver, based on: - the version of Freescale LPUART driver after commit b3e3bf2ef2c7 ("Merge 4.0-rc7 into tty-next"); - commit abf1e0a98083 ("tty: serial: fsl_lpuart: lock port on console write"). In this basic version, the driver can be tested using initramfs and relies on the clocks and pin muxing set up by U-Boot. Remarks concerning the earlycon support: - LinFlexD does not allow character transmissions in the INIT mode (see section 47.4.2.1 in the reference manual[1]). Therefore, a mutual exclusion between the first linflex_setup_watermark/linflex_set_termios executions and linflex_earlycon_putchar was employed and the characters normally sent to earlycon during initialization are kept in a buffer and sent afterwards. - Empirically, character transmission is also forbidden within the last 1-2 ms before entering the INIT mode, so we use an explicit timeout (PREINIT_DELAY) between linflex_earlycon_putchar and the first call to linflex_setup_watermark. - U-Boot currently uses the UART FIFO mode, while this driver makes the transition to the buffer mode. Therefore, the earlycon putchar function matches the U-Boot behavior before initializations and the Linux behavior after. [1] https://www.nxp.com/webapp/Download?colCode=S32V234RM Signed-off-by: Stoica Cosmin-Stefan <cosmin.stoica@nxp.com> Signed-off-by: Adrian.Nitu <adrian.nitu@freescale.com> Signed-off-by: Larisa Grigore <Larisa.Grigore@nxp.com> Signed-off-by: Ana Nedelcu <B56683@freescale.com> Signed-off-by: Mihaela Martinas <Mihaela.Martinas@freescale.com> Signed-off-by: Matthew Nunez <matthew.nunez@nxp.com> [stefan-gabriel.mirea@nxp.com: Reduced for upstreaming and implemented earlycon support] Signed-off-by: Stefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com> Link: https://lore.kernel.org/r/20190809112853.15846-6-stefan-gabriel.mirea@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-09 11:29:16 +00:00
tty: serial: Add linflexuart driver for S32V234 Introduce support for LINFlex driver, based on: - the version of Freescale LPUART driver after commit b3e3bf2ef2c7 ("Merge 4.0-rc7 into tty-next"); - commit abf1e0a98083 ("tty: serial: fsl_lpuart: lock port on console write"). In this basic version, the driver can be tested using initramfs and relies on the clocks and pin muxing set up by U-Boot. Remarks concerning the earlycon support: - LinFlexD does not allow character transmissions in the INIT mode (see section 47.4.2.1 in the reference manual[1]). Therefore, a mutual exclusion between the first linflex_setup_watermark/linflex_set_termios executions and linflex_earlycon_putchar was employed and the characters normally sent to earlycon during initialization are kept in a buffer and sent afterwards. - Empirically, character transmission is also forbidden within the last 1-2 ms before entering the INIT mode, so we use an explicit timeout (PREINIT_DELAY) between linflex_earlycon_putchar and the first call to linflex_setup_watermark. - U-Boot currently uses the UART FIFO mode, while this driver makes the transition to the buffer mode. Therefore, the earlycon putchar function matches the U-Boot behavior before initializations and the Linux behavior after. [1] https://www.nxp.com/webapp/Download?colCode=S32V234RM Signed-off-by: Stoica Cosmin-Stefan <cosmin.stoica@nxp.com> Signed-off-by: Adrian.Nitu <adrian.nitu@freescale.com> Signed-off-by: Larisa Grigore <Larisa.Grigore@nxp.com> Signed-off-by: Ana Nedelcu <B56683@freescale.com> Signed-off-by: Mihaela Martinas <Mihaela.Martinas@freescale.com> Signed-off-by: Matthew Nunez <matthew.nunez@nxp.com> [stefan-gabriel.mirea@nxp.com: Reduced for upstreaming and implemented earlycon support] Signed-off-by: Stefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com> Link: https://lore.kernel.org/r/20190809112853.15846-6-stefan-gabriel.mirea@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-09 11:29:16 +00:00
tty: serial: Add linflexuart driver for S32V234 Introduce support for LINFlex driver, based on: - the version of Freescale LPUART driver after commit b3e3bf2ef2c7 ("Merge 4.0-rc7 into tty-next"); - commit abf1e0a98083 ("tty: serial: fsl_lpuart: lock port on console write"). In this basic version, the driver can be tested using initramfs and relies on the clocks and pin muxing set up by U-Boot. Remarks concerning the earlycon support: - LinFlexD does not allow character transmissions in the INIT mode (see section 47.4.2.1 in the reference manual[1]). Therefore, a mutual exclusion between the first linflex_setup_watermark/linflex_set_termios executions and linflex_earlycon_putchar was employed and the characters normally sent to earlycon during initialization are kept in a buffer and sent afterwards. - Empirically, character transmission is also forbidden within the last 1-2 ms before entering the INIT mode, so we use an explicit timeout (PREINIT_DELAY) between linflex_earlycon_putchar and the first call to linflex_setup_watermark. - U-Boot currently uses the UART FIFO mode, while this driver makes the transition to the buffer mode. Therefore, the earlycon putchar function matches the U-Boot behavior before initializations and the Linux behavior after. [1] https://www.nxp.com/webapp/Download?colCode=S32V234RM Signed-off-by: Stoica Cosmin-Stefan <cosmin.stoica@nxp.com> Signed-off-by: Adrian.Nitu <adrian.nitu@freescale.com> Signed-off-by: Larisa Grigore <Larisa.Grigore@nxp.com> Signed-off-by: Ana Nedelcu <B56683@freescale.com> Signed-off-by: Mihaela Martinas <Mihaela.Martinas@freescale.com> Signed-off-by: Matthew Nunez <matthew.nunez@nxp.com> [stefan-gabriel.mirea@nxp.com: Reduced for upstreaming and implemented earlycon support] Signed-off-by: Stefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com> Link: https://lore.kernel.org/r/20190809112853.15846-6-stefan-gabriel.mirea@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-09 11:29:16 +00:00
tty: serial: Add linflexuart driver for S32V234 Introduce support for LINFlex driver, based on: - the version of Freescale LPUART driver after commit b3e3bf2ef2c7 ("Merge 4.0-rc7 into tty-next"); - commit abf1e0a98083 ("tty: serial: fsl_lpuart: lock port on console write"). In this basic version, the driver can be tested using initramfs and relies on the clocks and pin muxing set up by U-Boot. Remarks concerning the earlycon support: - LinFlexD does not allow character transmissions in the INIT mode (see section 47.4.2.1 in the reference manual[1]). Therefore, a mutual exclusion between the first linflex_setup_watermark/linflex_set_termios executions and linflex_earlycon_putchar was employed and the characters normally sent to earlycon during initialization are kept in a buffer and sent afterwards. - Empirically, character transmission is also forbidden within the last 1-2 ms before entering the INIT mode, so we use an explicit timeout (PREINIT_DELAY) between linflex_earlycon_putchar and the first call to linflex_setup_watermark. - U-Boot currently uses the UART FIFO mode, while this driver makes the transition to the buffer mode. Therefore, the earlycon putchar function matches the U-Boot behavior before initializations and the Linux behavior after. [1] https://www.nxp.com/webapp/Download?colCode=S32V234RM Signed-off-by: Stoica Cosmin-Stefan <cosmin.stoica@nxp.com> Signed-off-by: Adrian.Nitu <adrian.nitu@freescale.com> Signed-off-by: Larisa Grigore <Larisa.Grigore@nxp.com> Signed-off-by: Ana Nedelcu <B56683@freescale.com> Signed-off-by: Mihaela Martinas <Mihaela.Martinas@freescale.com> Signed-off-by: Matthew Nunez <matthew.nunez@nxp.com> [stefan-gabriel.mirea@nxp.com: Reduced for upstreaming and implemented earlycon support] Signed-off-by: Stefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com> Link: https://lore.kernel.org/r/20190809112853.15846-6-stefan-gabriel.mirea@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-09 11:29:16 +00:00
tty: serial: Add linflexuart driver for S32V234 Introduce support for LINFlex driver, based on: - the version of Freescale LPUART driver after commit b3e3bf2ef2c7 ("Merge 4.0-rc7 into tty-next"); - commit abf1e0a98083 ("tty: serial: fsl_lpuart: lock port on console write"). In this basic version, the driver can be tested using initramfs and relies on the clocks and pin muxing set up by U-Boot. Remarks concerning the earlycon support: - LinFlexD does not allow character transmissions in the INIT mode (see section 47.4.2.1 in the reference manual[1]). Therefore, a mutual exclusion between the first linflex_setup_watermark/linflex_set_termios executions and linflex_earlycon_putchar was employed and the characters normally sent to earlycon during initialization are kept in a buffer and sent afterwards. - Empirically, character transmission is also forbidden within the last 1-2 ms before entering the INIT mode, so we use an explicit timeout (PREINIT_DELAY) between linflex_earlycon_putchar and the first call to linflex_setup_watermark. - U-Boot currently uses the UART FIFO mode, while this driver makes the transition to the buffer mode. Therefore, the earlycon putchar function matches the U-Boot behavior before initializations and the Linux behavior after. [1] https://www.nxp.com/webapp/Download?colCode=S32V234RM Signed-off-by: Stoica Cosmin-Stefan <cosmin.stoica@nxp.com> Signed-off-by: Adrian.Nitu <adrian.nitu@freescale.com> Signed-off-by: Larisa Grigore <Larisa.Grigore@nxp.com> Signed-off-by: Ana Nedelcu <B56683@freescale.com> Signed-off-by: Mihaela Martinas <Mihaela.Martinas@freescale.com> Signed-off-by: Matthew Nunez <matthew.nunez@nxp.com> [stefan-gabriel.mirea@nxp.com: Reduced for upstreaming and implemented earlycon support] Signed-off-by: Stefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com> Link: https://lore.kernel.org/r/20190809112853.15846-6-stefan-gabriel.mirea@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-09 11:29:16 +00:00
serial: mvebu-uart: implement UART clock driver for configuring UART base clock Implement a new device driver for controlling UART clocks on Marvell Armada 3700 SoC. This device driver is loaded for devices which match the compatible string "marvell,armada-3700-uart-clock". There are more pitfalls related to UART clocks: - both UARTs use same parent clock source (which can be xtal or one of the TBG clocks), - if a TBG clock is used as the parent clock, there are two additional divisors that can both be configured to divide the rate by 1, 2, ... 6, but these divisors are again shared between the two UART controllers on the SOC, - the configuration of the parent clock source and divisors is done in the address space of the first UART controller, UART1. Clocks can be gated separately for UART1 and UART2, but this setting also lives in the address space of UART1, - Marvell's Functional Specification for Armada 3720 document has the clock gating bits swapped, so the one described to gate UART1 clock actually gates UART2 and vice versa, - each UART has it's own "special divisor", and this uses the parent clock described above. These divisors are configure in each UART's address space separately. Thus the driver for UART2 controller needs to have access to UART1 address space, since UART1 address space contains some bits exclusive for UART2 and also some bits which are shared between UART1 and UART2. Also, during boot, when early console is active on one of the UARTs, and we want to switch parent clock from xtal (default) to TBG (to be more flexible with baudrates), the driver changing UART clocks also needs to be able to change the "special divisor", so that the baudrate of earlycon is not changed when swtiching to normal console. Thus the clock driver also needs to be able to access UART2 register space, for UART2's "special divisor". For these reasons, this new UART clock driver does not use ioremap_resource(), but only ioremap() to prevent resource conflicts between UART clock driver and UART driver. We need to share only two 32-bit registers between the UART driver and the UART clock driver: - UART Clock Control - UART 2 Baud Rate Divisor Access to these two registers are protected by one spinlock to prevent any conflicts. Access is required only during probing, when changing baudrate or during suspend/resume. Hardware can be configured to use one of following clocks as UART parent clock: TBG-A-P, TBG-B-P, TBG-A-S, TBG-B-S, xtal. Not every clock is usable for higher buadrates. Any subset can be specified in the device-tree and the driver will choose the best one which also still supports the mandatory baudrate of 9600 Bd. For smooth boot log output it is needed to specify clock used by early console, otherwise garbage would be printed on UART during probe of UART clock driver and transitioning from early console to normal console. We are implementing this to be able to configure TBG clock as UART parent clock, which is required to be able to achieve higher baudrates than 230400 Bd. We achieve this by referencing this new UART clock device node in UART's device node. UART clock device driver automatically chooses the best clock source for UART driver. Until now, UART's device-tree node needed to reference one of the static clocks (xtal or one of the TBGs) as parent clock in the `clocks` phandle - the parent clock which was configured before booting the kernel. If bootloader changed UART's parent clock, it needed to change the `clocks` phandle in DTB correspondingly before booting. From now on both the old mechanism (xtal or TBG referenced as parent clock in `clocks` phandle) and the new one (UART clock referenced in the `clocks` phandle) are supported, to provide full backward compatibility with existing DTS files, full backward compatibility with existing boot loaders, and to provide new features (runtime clock configuration to allow higher baudrates than 230400 Bd). New features are available only with new DTS files. There was also a discussion about how the UART node and the clock-controller node could be wrapped together in a new binding [1, 2]. As explained there, this is not possible if we want to keep backwards compatibility with existing bootloaders, and thus we are doing this by putting the UART clock-controller node inside the UART1 node. [1] https://lore.kernel.org/linux-serial/20220120000651.in7s6nazif5qjkme@pali/ [2] https://lore.kernel.org/linux-serial/20220125204006.A6D09C340E0@smtp.kernel.org/ Reviewed-by: Marek Behún <kabel@kernel.org> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Marek Behún <kabel@kernel.org> Link: https://lore.kernel.org/r/20220219152818.4319-4-kabel@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-19 16:28:15 +01:00