| Message ID | 1555264206-19673-1-git-send-email-amittomer25@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4] xen/arm: Add Amlogic Meson SoCs earlyprintk support | expand |
Hi, On 14/04/2019 18:50, Amit Singh Tomar wrote: > This patch adds earlyprintk support for Amlogic Meson SoC based > boards. > > ATF[1] and U-boot[2] already initialize the UART for us. So no need to do it again. > > Tested With: > http://wiki.friendlyarm.com/wiki/index.php/NanoPi_K2 > > [1]: https://github.com/ARM-software/arm-trusted-firmware/blob/master/drivers/meson/console/aarch64/meson_console.S#L92 > [2]: https://github.com/u-boot/u-boot/blob/master/drivers/serial/serial_meson.c#L44 > > Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com> Acked-by: Julien Grall <julien.grall@arm.com> I have pushed to my branch next-4.13 for now. It will be merged once the commit moratorium is lifted. Cheers, > --- > Changes since v3: > > * Change the commit message to include firmware names. > > Changes since v2: > > * Added the commit message that talks about > uart initialization. > > * Added dummy early_uart_init function. > > Changes since v1: > > * Fixed coding style issue. > * Undone changes in early-printk.txt. > > Changes since RFC: > > * Replaced LDRH with LDR, with this there > is no scattered output on console now. > * Used tbnz instead of tst and b.ne. > * Used AML_ prefix against register names. > > --- > xen/arch/arm/arm64/debug-meson.inc | 55 ++++++++++++++++++++++++++++++++++++++ > 1 file changed, 55 insertions(+) > create mode 100644 xen/arch/arm/arm64/debug-meson.inc > > diff --git a/xen/arch/arm/arm64/debug-meson.inc b/xen/arch/arm/arm64/debug-meson.inc > new file mode 100644 > index 0000000..e1a8fa8 > --- /dev/null > +++ b/xen/arch/arm/arm64/debug-meson.inc > @@ -0,0 +1,55 @@ > +/* > + * xen/arch/arm/arm64/debug-meson.inc > + * > + * MESON specific debug code. > + * > + * Copyright (c) 2019, Amit Singh Tomar <amittomer25@gmail.com>. > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms and conditions of the GNU General Public > + * License, version 2, as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * General Public License for more details. > + * > + * You should have received a copy of the GNU General Public > + * License along with this program; If not, see <http://www.gnu.org/licenses/>. > + */ > + > +#define AML_UART_WFIFO_REG 0x00 > +#define AML_UART_STATUS_REG 0x0c > + > +#define AML_UART_TX_FIFO_FULL 21 > + > +.macro early_uart_init xb, c > +/* Uart has already been initialized by Firmware, for instance by TF-A */ > +.endm > + > +/* > + * MESON UART wait UART to be ready to transmit > + * xb: register which contains the UART base address > + * c: scratch register > + */ > +.macro early_uart_ready xb c > +1: > + ldr w\c, [\xb, #AML_UART_STATUS_REG] /* status register */ > + tbnz w\c, #AML_UART_TX_FIFO_FULL, 1b /* Check TXFIFO FULL bit */ > +.endm > + > +/* > + * MESON UART transmit character > + * xb: register which contains the UART base address > + * wt: register which contains the character to transmit > + */ > +.macro early_uart_transmit xb wt > + str \wt, [\xb, #AML_UART_WFIFO_REG] > +.endm > + > +/* > + * Local variables: > + * mode: ASM > + * indent-tabs-mode: nil > + * End: > + */ >
diff --git a/xen/arch/arm/arm64/debug-meson.inc b/xen/arch/arm/arm64/debug-meson.inc new file mode 100644 index 0000000..e1a8fa8 --- /dev/null +++ b/xen/arch/arm/arm64/debug-meson.inc @@ -0,0 +1,55 @@ +/* + * xen/arch/arm/arm64/debug-meson.inc + * + * MESON specific debug code. + * + * Copyright (c) 2019, Amit Singh Tomar <amittomer25@gmail.com>. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms and conditions of the GNU General Public + * License, version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; If not, see <http://www.gnu.org/licenses/>. + */ + +#define AML_UART_WFIFO_REG 0x00 +#define AML_UART_STATUS_REG 0x0c + +#define AML_UART_TX_FIFO_FULL 21 + +.macro early_uart_init xb, c +/* Uart has already been initialized by Firmware, for instance by TF-A */ +.endm + +/* + * MESON UART wait UART to be ready to transmit + * xb: register which contains the UART base address + * c: scratch register + */ +.macro early_uart_ready xb c +1: + ldr w\c, [\xb, #AML_UART_STATUS_REG] /* status register */ + tbnz w\c, #AML_UART_TX_FIFO_FULL, 1b /* Check TXFIFO FULL bit */ +.endm + +/* + * MESON UART transmit character + * xb: register which contains the UART base address + * wt: register which contains the character to transmit + */ +.macro early_uart_transmit xb wt + str \wt, [\xb, #AML_UART_WFIFO_REG] +.endm + +/* + * Local variables: + * mode: ASM + * indent-tabs-mode: nil + * End: + */
This patch adds earlyprintk support for Amlogic Meson SoC based boards. ATF[1] and U-boot[2] already initialize the UART for us. So no need to do it again. Tested With: http://wiki.friendlyarm.com/wiki/index.php/NanoPi_K2 [1]: https://github.com/ARM-software/arm-trusted-firmware/blob/master/drivers/meson/console/aarch64/meson_console.S#L92 [2]: https://github.com/u-boot/u-boot/blob/master/drivers/serial/serial_meson.c#L44 Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com> --- Changes since v3: * Change the commit message to include firmware names. Changes since v2: * Added the commit message that talks about uart initialization. * Added dummy early_uart_init function. Changes since v1: * Fixed coding style issue. * Undone changes in early-printk.txt. Changes since RFC: * Replaced LDRH with LDR, with this there is no scattered output on console now. * Used tbnz instead of tst and b.ne. * Used AML_ prefix against register names. --- xen/arch/arm/arm64/debug-meson.inc | 55 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 xen/arch/arm/arm64/debug-meson.inc